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AUDIOVISUAL  CONSERVATION 
at  The  LIBRARY  cf  CONGRESS 


Packard  Campus 

for  Audio  Visual  Conservation 

www.loc.gov/avconservation 

Motion  Picture  and  Television  Reading  Room 
www.loc.gov/rr/mopic 

Recorded  Sound  Reference  Center 
www.loc.gov/rr/record 


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S     -+A. 


JANUARY 


1949 


VOLUME  24       •       NUMBER   1 


30c  A  COPY    •    S2.50  A  YEAR 


©C1B    172705 


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!    MM! 

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3 


THIS  IS  HARD 


0UT  THIS  IS  EASY 


AND  THIS  IS 
MIGHTY  WONDERFUL 


i&ure,  you  believe  in  saving. 

But  it's  mighty  hard  to  make  yourself  take  cash 
out  of  your  pocket,  and  time  out  of  your  day,  to  do 
it  regularly. 

The  sure  way,  the  easy  way  to  do  your  saving  is 
to  get  started  on  an  automatic  savings  plan  with 
U.  S.  Savings  Bonds.  Like  this  . . . 

1 .  If  you're  on  a  payroll,  sign  up  in  the  Payroll 
Savings  Plan,  then  forget  it.  From  then  on  the 
money  saves  itself — so  much  per  week,  or  so 
much  per  month. 

2.  If  you're  not  on  a  payroll,  sign  up  at  your 
bank  for  the  Bond-A-Month  Plan.  Equally  easy. 
You  decide  how  much  you  want  to  put  into 
bonds  every  month,  your  bank  does  the  rest. 

In  just  ten  years  after  you  start  buying  bonds,  your 
money  starts  coming  back  to  you — well-fattened! 
Every  33  you  invest  today  brings  you  back  $4  to 
make  possible  all  the  wonderful  things  you  dream  of 
doing. 

And  remember — any  time  you  need  your  money  for 
emergencies,  you  can  get  it  back  in  minutes,  without 
losing  interest. 


Automatic  savingls  sure  saving- U.S.  Savings  Bonds 


Contributed  by  this  magazine  in  co-operation  with  the  Magazine  Publishers  of  America  as  a  public  service. 


X 


INTERNATIONAL 

RQJECTIONISI 


With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


JANUARY  1949 


Number  1 


1/ 


Index  and  Monthly  Chat 3 

Sound  System  Components,  III  .        5 
Robert  A.  Mitchell 

The  Concave  Screen 10 

Projected  Light  and  the  Curved 
Screen 10 

Historical  Sketch  of  Tv  Progress     11 
L.  R.  Lankes 

Emphasis  on  the  Port  Side  ...      12 
A.  Buckley 

Sound  Kodascope  FB-40  Projec- 
tor Again  Available 14 

Ultrafax:    New  Communication 
Marvel 15 


Expanding     Use     of    Infra-Red 

Film 16 

Archie  Stout 

Flicker  in  Motion  Pictures  ....      17 

Effective  First-Aid  in  the  Event 
of  Electric  Shock 17 

In  The  Spotlight .      18 

Lumens  and  Electrons 20 

W.  W.  Lozier 
F.  T.  Bowditch 

I.  A.  Elections 24 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING   CO.,   INC. 

19  West  44  Street,  New  York   18,  N.   Y. 

R.   A.   ENTRACHT,   Publisher 

SUBSCRIPTION   REPRESENTATIVES 

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act  of  March  3,.  1879/  Entire  contents  copyrighted  194'8/'by  International  Projectionist 
Publishing  Co.,  Inc.  "Jnternational  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 




MONTHLY   CHAT 


WHILE  there  were  few  outward  signs 
of  any  sharp  advances  technologi- 
cally within  projection  circles  during 
1948,  it  would  be  less  than  wise  to  mark  '4-  II 
that  period  off  as  a  wholly  static  year. 
Plans  formulated  and  research,  develop- 
ment and  testing  effort  expended  during 
1948  will  blossom  into  actuality  during 
the  coming  year  and,  possibly,  through 
several  years  thereafter. 

No  branch  of  the  motion  picture  in- 
dustry— from  managers  and  projection- 
ists in  theatres  on  up  through  the  studio 
artistic  and  technical  forces  to  the  higher 
echelon  of  management  (and  not  forget- 
ting those  hard-headed  fellows  from  Wall 
Street  and  its  counterparts  who  supply 
the  wherewithal)  nobody  is  unaware  of 
the  tremendous  task  that  confronts  the 
industry  in  its  life-or-death  struggle  to 
combat  the  many  forms  of  entertainment 
which  now  compete  with  the  film  box- 
office  dollar.  Rampant  though  it  be  at 
the  moment,  television  is  by  no  means  the 
only  threat  to  the  theatre  box-office;  Tv 
merely  intensifies  the  competition. 

If  the  film  industry  is  to  continue  as 
a  healthy  economic  organism,  it  appears 
certain  that  the  life-sustaining  energy 
must  flow  from  its  technicians.  Films 
must  be  made  very  much  more  appealing 
to  the  increasingly  discerning  eye  of  the 
amusement-seeker,  not  only  in  terms  of 
story  content  and  artistic  execution  but 
also  by  means  of  vastly  improved  tech- 
nique in  production  and  presentation. 

Three-dimensional  pictures,  stereo- 
phonic sound  and  greatly  improved  color 
processes  are  but  three  of  the  advances 
long  promised  by  the  film  industry;  but 
it  begins  to  look  as  though  the  Big  Brass 
executives  have  become  very  coy  about 
putting  money  into  technological  devel- 
opments on  behalf  of  an  industry  which, 
while  the  source  of  their  opulence  and 
personal  power,  might  possibly  be  in  for 
a  bit  of  rough  going.  Difficult  of  accom- 
plishment though  the  aforementioned  de- 
velopments might  be,  complete  candor 
compels  the  observation  that  they  would 
be  duck  soup  for  that  gang  of  technicians 
who  have  brought  Tv  to  its  comparatively 
high  estate. 

There  is  more  than  a  suspicion  that  the 
Big  Brass  is  flirting  with  the  notion  of 
going  over  into  the  Tv  camp  en  masse 
(strictly  as  a  production  enterprise  in 
studios  already  available)  and  let  the 
exhibition  field  make  its  own  way.  This 
suspicion  is  strengthened  by  the  strange 
apathy  displayed  by  film  executives  in 
moving  to  avail  themselves  of  even  a  sin- 
gle Tv  channel  for  theatre  use. 

So,  whatever  the  desires  and  capabih- 
ties  of  its  technical  forces,  the  immediate 
and  long-range  welfare  of  the  motion 
picture  industry  will  be  decided  largely 
by  the  decisions  made  in  executive  eeries 
in  New  York.  We  shall  know  the  answer 
before  1949  is  very  far  advanced. 


INTERNATIONAL  PROJECTIONIST 


January  1949 


Laurence  Olivier's  presentation  of 


comes  to  life  on 

a  WESTERN  ELECTRIC  Sound  Track 


Laurence  Olivier's  magnificent 
version  of  Shakespeare's  tragedy 
was  recorded  on  Western  Electric 
sound  equipment.  The  new  De  Luxe 
"400"  Recording  System   and  the   new 
RA-1251  Re-recorders  have  demonstrated 
once  more  their  reliability  and  outstand- 
ing performance. 

Such  advantages  as  automatic  opera- 
tion, highest  sound  quality  and  versatility 
make  the  "400"  the  outstanding  record- 
ing system  available  to  the  industry. 


ff&Mtec 


Produced  and  Directed  by    .  Laurence  Olivier 

Recorded  at     ....     .     .  .  Deaham  Studios 

Sound  Supervisor     .     .     .     .  ,  Cyril  Crowhurst 

Sound  by     .......  .  Western  Blectric 


INTERNATIONAL  PROJECTIONIST 


January  1949 


VOLUME  XXIV 


JANUARY    1949 


NUMBER  1 


Sound  System  Components 


ONE  of  the  most  conspicuous  fea- 
tures of  an  electric  current  is  the 
phenomenon  of  polarity,  the  dis- 
tinction between  positive  and  negative 
potentiality.  This  characteristic  of  elec- 
tricity may  be  ascribed  to  the  fact  that 
the  flow  of  current  in  a  circuit  is  uni- 
directional at  any  specified  instant.  As 
an  illustration,  consider  the  terminals  of 
a  dry  cell:  when  a  circuit  is  established 
by  connecting  the  two  terminals,  current 
leaves  one  terminal  and  enters  the  other. 

It  is  absurd  to  think  of  electricity  as 
consisting  of  two  separate  kinds,  posi- 
tive and  negative,  which  seek  to  join  or 
"amalgamate,"  as  one  writer  of  projec- 
tion texts  quaintly  expresses  it.  Elec- 
tricity is  a  single  entity.  Polarity  is 
merely  the  result  of  direction  of  flow. 

Until  the  latter  part  of  the  last  cen- 
tury electrical  engineers  had  no  way  of 
knowing  which  way  electricity  moves. 
The  early  supposition  that  current  flows 
from  positive  to  negative  was  incorrect; 
we  now  know  that  the  reverse  is  true. 
The  older  incorrect  theory  nevertheless 
still  survives  in  our  custom  of  tracing 
d-c  circuits  from  positive  to  negative, 
and  also  in  the  practice  of  grounding  the 
negative  side  of  amplifier  circuits. 

A  study  of  the  action  of  electron  tubes 
and  photoelectric  cells  proves  conclu- 
sively that  electric  current  flows  from 
negative  to  positive.  For  the  present, 
however,  let  us  ignore  these  purely  scien- 
tific considerations  and  delve  into  the 
eminently  practical  problem  of  deter- 
mining which  of  two  wires  conducting 
d-c  is  positive  and  which  is  negative. 

Many  electrical  appliances — incan- 
descent lamps,  heaters,  d-c  motors,  bells, 


By  ROBERT  A.  MITCHELL 
III.    Alternating  Currents 

buzzers,  etc. — do  not  require  specified 
polarity  connections.  Their  operation  is 
not  affected  in  the  slightest  degree  when 
their  leads  are  reversed.  But  certain 
other  d-c-operated  devices — arc  lamps, 
.  photocells,  amplifier  tubes,  etc. — must 
be  properly  connected  with  respect  to 
polarity  if  they  are  to  operate. 

Tests  for  Polarity 

There  are  several  good  tests  for  polar- 
ity at  the  disposal  of  projectionists.  A 
d-c  voltmeter,  the  terminals  of  which  are 
correctly  marked  +  and  — ,  provides  the 
simplest  and  most  rapid  test.  When  cor- 
rectly "poled"  (positive  wire  to  +  ter- 
minal; negative  wire  to  —  terminal)  the 
voltage  will  be  indicated  by  the  meter. 
If,  however,  the  wires  be  reversed,  no 
reading  will  be  obtained.  (In  such  a 
case  the  pointer  will  be  impelled  to  swing 
over  to  the  off-scale  side  of  zero.) 

Another  test  requires  the  acquisition 
of  a  fresh  raw  potato.  The  white  part  of 
a  thick  slice  of  the  potato  is  touched  by 
the  two  copper  wires  charged  with  d-c. 
For  best  results  the  two  wires  should  be 
thrust  into  the  slice  about  half  an  inch 
apart.  In  a  minute  or  more,  depending 
on  the  voltage,  the  potato  will  be  stained 
green  around  the  positive  wire. 

In  the  aforementioned  test  the  slice  of 
potato  serves  as  a  crude  sort  of  "test 
strip,"  but  those  who  wish  may  easily 
prepare  professional  polarity  test  paper. 
This  is  accomplished  by  soaking  white 
blotting  paper  in  a  solution  of  salt  water 


to  which  a  small  quantity  of  phenolph- 
thalein  in  alcohol  has  been  added.1  The 
paper  is  allowed  to  dry  and  is  stored  for 
future  use.  To  test  polarity,  a  strip  of 
the  test  paper  is  moistened  with  water 
and  touched  by  the  two  wires  carrying 
d-c.  A  bright  red  stain  will  develop  on 
the  paper  surrounding  the  negative  wire. 
A  fourth  test  for  polarity  involves  the 
electrolysis  of  water.  Introduce  the  two 
uninsulated  wires  into  a  glass  of  water 
containing  a  pinch  of  salt.  The  wires 
should  be  held  about  an  inch  apart.  In 
a  short  time — depending  on  the  strength 
of  the  current — bubbles  of  hydrogen  gas 
will  collect  around  the  negative  wire  and 
tend  to  cling  to  it. 

Alternating  Currents;  Frequency 

If  the  circuit  connections  to  the  ter- 
minals of  a  dry  cell  or  other  source  of 
d-c  be  continually  reversed,  the  e.m.f 
(electromotive  force,  or  voltage)  will  be 
periodically  reversed  in  polarity.  Instead 
of  a  continuous  d-c,  a  reversing  and  pul- 
sating, or  alternating,  current  will  flow 
through  the  circuit. 

The  laws  which  govern  the  flow  of  a-c 
are  much  more  complicated  than  those 
which  obtain  with  continuous  d-c,  but  so 
important  is  a-c  in  sound  amplification 
that  its  study,  though  difficult,  is  well 
worth  our  time  and  effort. 

The  rate  of  periodic  reversal  of  a-c 
is  called  the  frequency  of  the  current. 
It  is  usually  measured  in  cycles  per 
second.  For  60-cycle  a-c,  the  current 
flows   in    one    direction   for    1/120   of   a 

1  Dissolve  15  grains  of  colorless  phenolphthalein  in 
a  small  quantity  of  alcohol.  Add  the  alcoholic  solu- 
tion of  phenolphthalein  to  4  fluid  ounces  of  water  in 
which  75  grains  of  salt  (sodium  chloride)  have  been 
dissolved. 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


second;  during  the  next  1/120  second  it 
flows  in  the  other  direction.  The  complete 
cycle  therefore  takes  2/120,  or  1/60,  sec- 
ond; hence  we  say  that  the  frequency 
of  the  current  is  60  cycles  per  second. 

Because  the  direction  of  current-flow 
does  not  affect  the  operation  of  incan- 
descent lamps,  a  lamp  burning  on  60- 
cycle  current  brightens  and  dims  120 
times  every  second.  It  follows  from  this 
-hat  soundhead  exciting  lamps  powered 
by  60-cycle  current  produce  a  120-cycle 
hum  in  the  sound,  but  this  is  so  faint 
that  it  is  not  heard  during  the  presenta- 
tion of  the  picture. 

The  alternating  audio  (sound)  cur- 
rents fed  into  the  voice  coils  of  theatre 
speakers  have  frequencies  ranging  from 
30  to  9,000  c.p.s.  This  range  includes 
the  principal  frequencies  of  sound  which 
can  be  appreciated  by  the  human  ear. 

The  Generation  of  A-C 

A-C  intended  for  power  purposes  is 
produced  by  electromagnetic  induction 
in  a-c  generators,  but  in  special  cases 
a-c  is  made  by  rapidly  interrupting  the 
flow  of  d-c,  the  periodic  reversal  of  po- 
larity being  produced  by  the  "reactance" 
of  inductive  coils  or  condensers. 

The  simplest  way  to  generate  a-c  is 
to  move  a  bar  magnet  rapidly  in  and  out 
of  a  coil  of  wire.  As  the  magnet  moves 
in,  the  magnetic  field  "cuts"  the  coil  and 
drags  electrons  along,  thus  producing  a 
single  pulsation  of  electric  current  in  one 
direction;  but  when  the  magnet  is  with- 
drawn, another  pulsation  is  produced, 
but  it  flows  in  the  opposite  direction.  The 
two  pulsations  constitute  one  cycle  of 
a-c.  Additional  pulsations  merely  repeat 
the  first  two. 

Such  a  method  of  making  a-c  is  clearly 
impractical.  We  may  improve  on  the 
simple  apparatus  by  rotating  the  coil  of 
wire  between  the  poles  of  a  powerful 
horseshoe  magnet,  and  to  increase  the 
magnetic  effectiveness  of  the  coil  we  pro- 
vide it  with  a  laminated  core  of  soft  iron. 
The  problem  of  taking  the  current  from 
the  whirling  coil  is  solved  by  the  use  of 
collector  rings  and  brushes.2 

One  complete  revolution  of  the  coil  of 
our  simple  bipolar  alternator  results  in 
one  complete  cycle  of  a-c.  During  this 
cycle  the  current  gradually  rises  from 
zero,  builds  up  to  a  maximum  value,  and 
falls  to  zero  again;  whereupon  the  pro- 
cess repeats,  but  with  reversed  polarity. 
The  wire  which  is  positively  charged 
during  the  first  pulsation,  or  half-cycle, 
will  be  negatively  charged  during  the 
second  half-cycle. 

The  Sine  Wave 

The  fluctuations  of  current  (or  volt- 
age)  and  polarity  may  be  shown  graph- 


ically. If  there  are  no  magnetic  disturb- 
ances or  irregularities  in  the  action  of 
the  generator,  the  current  will  follow  a 
smooth  curve,  as  in  Figs.  1  and  2.  This 
type  of  curve,  the  simplest  possible,  is 
called  a  sine  wave. 

Figure  1  shows  what  is  meant  by  the 
term  "sine"  as  applied  to  this  wave.  A 
sine  is  one  of  the  trigonometric  func- 
tions, with  the  sines  of  angles  varying 
from  0  to  1,  positive  or  negative.  Fig.  1 
was  drawn  by  plotting  angles  against 
their  sines.  Since  one  cycle  of  a-c  cor- 
responds to  a  complete  angular  revolu- 
tion of  360  degrees,  one  set  of  ordinates 
(lines  on  the  graph)  was  assigned  angu- 
lar values  up  to  360  degrees;  while  the 
other  set  of  ordinates  was  given  the  val- 
ues of  the  sines  on  both  sides  of  0  (0  to 
+  1,  and  0  to  — 1). 

Now  the  sines  of  0°,  30°,  60°,  etc., 
may  be  tabulated  as  follows: 


sin  0°     =  0 

sin  30°   =  0.5 

sin  60°   =  0.866 

sin  90°   =  1.0 

sin  120°=  0.866 

sin  150°=  0.5 


sin  180°=  0 

sin  210°=  —0.5 

sin  240°=  —0.866 

sin  270°=  —1.0 

sin  300°=  —0.866 

sin  330°=  —0.5 


sin  360°=  0 

When  these  data  are  accurately  plotted 
on  the  coordinates  of  the  graph,  and  the 
points  connected  by  a  smooth  curve,  the 
sine  wave  seen  in  Fig.  1  results. 

Peak  and  Effective  Values 

Since  in  a-c  both  voltage  and  current 
swing  continuously  between  their  posi- 
tive and  negative  maximum  (peak)  val- 
ues,  it  may    be   wondered  how  we   can 


+1.0 
+  0.8 


91  +  0.6 


+  0.4 
+  0.2 


CO 


-0.2 
-0.4 
-0.6 
-0.8 
-1.0 


■*— 

—  One  cycle  - 

— >i 
i 

/ 

/ 

/ 

©S©2oooo© 
co    <o   a    «m    iaoo*-)    ^ 

H       H      «      «       N 


Angh 


o     o     o    o 
r»     O     CO     *o 

oJ    to    «    eo 


2  The  necessity  of  drawing  heavy  currents  through 
slip-rings  and  brushes  is  eliminated  in  commercial 
alternators  of  large  size  by  rotating  the  magnetic 
6eld  inside  a  stationary  ring  of  coils.  The  armature 
therefore  becomes  the  "stator,"  and  the  field  the 
"rotor."  * 


FIG.  1.    A  sine  wave. 

speak  of  "so  many  volts,"  or  "so  many 
amperes"  of  a-c.  The  difficulty  is  cleared 
up  by  using  effective  values  of  e.m.f. 
and  current  which  have  the  same  effect 
in  producing  heat  in  resistances  as  cor- 
responding d-c  values. 

A-c  voltmeters  and  ammeters  indicate 
effective  volts  and  effective  amperes. 

When  the  simple  sine  wave  is  con- 
sidered, a  direct  relation  is  discernible 
between  the  instantaneous  peak  values 
of  volts  (or  amperes)  and  the  effective 
values.  The  minimum  and  maximum 
values  of  e.m.f.    (or  current)    are  sepa- 


rated by  an  angular  difference  of  90 
degrees,  as  shown  by  Fig.  1.  The  mean 
of  0  degrees  and  90  degrees  is  45  de- 
grees, and  sin  45°  is  0.707.  So  if  the 
instantaneous  peak  value  of  voltage  or 
current  be  represented  by  1  (sin  90°), 
the  effective  value3  will  be  represented  by 
0.707   (sin  45°).    Hence: 

Effective  value  =  0.707  X  Peak  value 
Peak  value  =  1.414  X   Effective  value 

These  formulas  may  be  used  for  solving 
certain  types  of  problems.  As  an  exam- 
ple, suppose  an  A.C.  generator  develops 
+  and  —  peaks  of  12  volts.  What  is  the 
effective  voltage? 

Eeff.  =  0.707  X  12  =  8.484  volts 

As  another  illustration  consider  a  ca- 
pacitor connected  across  a  110-volt,  60- 
cycle  line.  Assuming  that  the  a-c  fluctua- 
tions follow  a  sine  wave,  what  peak  volt- 
age must  this  capacitor  withstand? 

Emax.  =  1.414  X  110  =  155.54  volts 

A.  C.  Characteristics 

The  simple  relationship  between  e.m.f., 
current,  and  resistance  in  a  d-c  circuit  is 
expressed  by  Ohm's  law.  It  is  only  when 
the  flow  of  current  is  started  or  stopped 
in  a  d-c  circuit  containing  inductive  or 
capacitative  devices  that  we  observe  oc- 
currences that  utterly  defy  Ohm's  law. 

Now,  these  "anomalous"  occurrences 
become  very  prominent  in  an  a-c  circuit 
because  a-c  is  a  current  which  starts  and 
stops  many  times  each  second.  We  are 
accordingly  forced  to  supplement  our 
knowledge  of  Ohm's  law  by  an  acquaint- 
ance with  inductance  and  capacitance  if 
we  are  to  deal  intelligently  with  alter- 
nating currents. 

Electromagnetic  Induction 

The  principle  of  electromagnetic  in- 
duction is  easy  to  understand.  When  a 
current  passes  through  a  conductor,  a 
magnetic  field  is  established  around  that 
conductor.  (This  is  the  result  of  elec- 
trons in  motion.)  Further,  when  a  mag- 
netic field  "cuts"  through  a  conductor, 
an  electromotive  force  is  generated  in 
that  conductor. 

But  remember :  no  e.m.f.  is  generated 
if  the  conductor  is  merely  in  the  magnetic 
field.  In  order  for  an  electric  potential 
to  be  set  up,  the  conductor  must  be 
moving  through  the  magnetic  field  (or 
the  magnetic  field  must  be  moving 
through  the  conductor,  which  is  the  same 
thing) . 

Summed  up,  we  may  say  that  a  mov- 
ing electric  field  produces  a  magnetic 
field,  and  that  a  moving  magnetic  field 
produces  an  electric  field. 

A  magnetic  field  which  varies  in 
strength  is  considered  to  be  in  motion 
(expanding       and      collapsing),       even 

3  The  author  holds  that  this  trigonometric  derivation 
of  the  effective  values  is  considerably  simpler  than 
the  "root-mean-square"  derivation  preferred  by  most 
electrical   writers. 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


"National"  high  intensity 
carbons  change  dim  screen 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


though  the  source  of  magnetic  flux  re- 
mains fixed  in  one  place. 

The  electromagnetic  induction  of  elec- 
tric current  is  the  underlying  principle 
of  generators  and  transformers:  the  for- 
mer utilizing  mechanically-rotated  mag- 
nets of  constant  strength,  and  the  latter 
fixed  magnets  of  fluctuating  strength.  It 
is  obvious  that  the  net  result  is  the  same 
in  both  cases:  currents  are  induced  by 
magnetic  fields  cutting  through  conduc- 
tors. 

Because  the  magnetic  fields  produced 
by  a  steady  d-c  are  non-varying  in  inten- 
sity, no  electromagnetic  induction  occurs 
in  a  d-c  circuit  unless  means  are  provided 
for  rapidly  varying  the  strength  of  the 
current.  When  a-c  is  considered,  how- 
ever, we  encounter  pronounced  self-in- 
duction, or  inductance,  effects. 

Effects  of  Inductance 

Assume  that  a  choke  is  connected  to  a 
suitable  source  of  d-c.  (A  choke  is  a 
coil  of  wire  wound  around  a  core  of  soft 
iron.)  The  coil  impedes  the  flow  of  d-c 
by  virtue  of  its  resistance — the  resistance 
of  the  wire.  The  value  of  the  resistance 
is  easily  calculated  by  Ohm's  law  when 
we  know  the  voltage-drop  and  the  cur- 
rent passed: 


R 


and  the  power  formula  gives  the  number 
of  watts  dissipated  in  the  resistance  as 
heat: 

P  =  EI 
When  the  same  choke  is  connected  to 
a  source  of  a-c  neither  the  Ohm's  law 
formula  nor  the  power  formula  hold 
good.  The  mathematical  product  of  volt- 
meter and  ammeter  readings  will  not  be 
the  true  power  consumed  by  the  choke. 


Indeed,  the  true  watts  (measured  by  a 
wattmeter)  will  be  vastly  less  than  the 
apparent  watts  obtained  by  multiplying 
volts  by  amperes. 

This  strange  state  of  affairs  is  due  to 
the  induction  of  an  opposing  e.m.f.  in  the 
choke.  Why  opposing?  An  important 
principle  known  as  Lenz's  law  tells  us 
that  an  induced  current  always  flows  in 
such  a  direction  that  it  opposes  (coun- 
teracts) the  magnetic  field  of  the  origi- 
nal current.  The  net  result  of  the  two 
currents  (the  applied  and  the  induced) 
flowing  in  the  same  circuit  is  a  time-dis- 
placement between  volts  and  amperes. 

In  other  words,  the  volt-peaks  and  the 
ampere-peaks  no  longer  coincide.  All 
inductive  devices  (chokes,  electromag- 
nets, transformers,  motors,  etc.)  cause 
the  current  changes  to  lag  behind  the 
voltage  changes.  Curve  B  in  Fig.  2 
shows  a  90-degree  current  lag. 

An  inductance  shifts  the  phase  in  this 
manner  because  the  induction  of  current 
is  greatest  when  the  applied  current  is 
changing  most  rapidly,  that  is,  when  it 
passes  through  the  zero  point.  We  thus 
find  that  the  induced  voltage  flows  in  a 
direction  opposite  to  the  supplied  cur- 
rent during  the  intervals  of  falling  cur- 
rent: hence  the  current  changes  are  said 
to  lag  behind  the  voltage  changes  by  90 
degrees  in  a  purely  inductive  circuit. 

Since  in  practice  there  is  always  some 
resistance  in  a  circuit,  the  current  lag 
due  to  inductance  may  approach,  but 
never  reach,  a  full  90  degrees. 

Wattless  Current 

Current  having  an  "angle  of  phase 
difference"  approaching  90  degrees  (cur- 
rent lagging  or  leading  by  nearly  90  de- 
grees) is  called  "wattless"  current.  Such 
a  current  is  obtained  when  we  feed  a-c 


CINEMA  NORMANDIE,  PARIS 

One  of  the  best  European  installations,  this  room  is  30  by  15  feet  and  utilizes  a  140-foot  throw. 

Equipment  includes  a  Western  Electric  M-2  sound  system  (3  machines);  Simplex  projectors,  Peerless 

lamps,  Hertner  Transverter,  and  a   Brenkert  effect  projector.    Installation   by  Westrex. 


(A) 


(B) 


,*- Volts 

Amperes 

180° 


>-Volts  Amperes 
^270° 


180° 


Volts 


O"  90 

-I   Amperes-* 


360° 


FIG.  2.  Alternating  current  curves:  (A)  e.m.f. 
and  current  in  phase;  (6)  current  lagging  by  90 
degrees;    (C)   current   leading   by   90    degrees. 

to  the  primary  of  a  transformer  whose 
secondary  circuit  is   open. 

Voltmeter  and  ammeter  readings  taken 
on  the  "live"  primary  circuit  will  indi- 
cate a  heavy  consumption  of  electric 
power,  but  the  watts  found  by  multiply- 
ing volts  by  amperes  are  largely  appa- 
rent watts.  (The  word  apparent  as  ap- 
plied to  watts  means  "seeming.")  The 
out-of-phase  components  of  the  wattless 
current  merely  surge  in  and  out  of  the 
transformer  without  the  expenditure  of 
power. 

It  is  for  this  reason  that  the  primary 
of  a  doorbell  transformer  may  be  per- 
manently connected  to  the  110-voIt  a-c 
line.  Except  when  the  volt  and  ampere 
components  are  brought  into  phase  by 
taking  power  from  the  secondary,  as  by 
ringing  a  doorbell,  the  power  consump- 
tion of  the  transformer  is  negligible. 
Because  inductance  does  not  figure  in  a 
d-c  circuit,  the  transformer  would  quick- 
ly burn  up  if  connected  to  a  source  of 
110  volts  of  d-c! 

Power  Factor 

In  order  to  calculate  the  power  dissi- 
pated in  an  a-c  circuit  (true  watts),  we 
must  multiply  the  product  of  volts  times 
amperes  by  a  factor  called  the  power 
factor  of  the  circuit.  The  power  factor  is 
the  cosine  of  the  angle  of  phase  differ- 
ence between  current  and  e.m.f.,  which 
angle  is  represented  by  the  Greek  letter 
phi,  </>. 

Vtrue  =  EI  cos  d> 

The  cosine  of  90°  of  current  lag  or 
lead  is  0,  hence  in  wattless  current  the 
value  of  the  true  watts  is  obviously  0. 
When  current  and  e.m.f.  are  in  phase 
(that  is,  when  volt-  and  ampere-peaks 
coincide),  the  phase  angle  is  0°;  and 
since  cos  0°  is  1,  the  value  of  the  true 
watts  is  the  full  product  of  volts  multi- 
plied by  amperes,  just  as  with  d-c. 

The  quotient  obtained  by  dividing  true 
watts  (determined  with  a  wattmeter)   by 
the  product  of  volts  times  amperes   (sep- 
(Continued  on  page  29) 


8 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


He  interprets  with  light 


•  This  scene,  from  the  moment  of  its  con- 
ception, had  dramatic  possibilities.  But  it 
was  the  director  of  photography  who  made 
them  more  than  possibilities. 

His  was  the  creative  skill,  the  spectacu- 
lar, interpretive  use  of  light  that  produced 
actual  drama,  vivid,  gripping  .  .  .  his  the 
perceptive  use  of  photography  that  made 
the  scene  an  intense  moment  of  visual 
reality. 


To  get  the  utmost  from  his  special  skill, 
his  creative  ability,  the  director  of  photog- 
raphy naturally  wants  a  superior  film,  one 
on  which  he  can  depend,  one  perfectly 
suited  to  the  conditions  and  circumstances 
under  which  he's  working.  That's  why  he 
so  often  prefers  Eastman  Plus-X  for  gen- 
eral studio  and  outdoor  use  .  .  .  and  why 
he  turns  to  Eastman  Super-XX  for  use 
under  adverse  lighting  conditions. 


EASTMAN    KODAK    COMPANY 


ROCHESTER    4,    N.    Y. 


J.   E.   BRULATOUR,   INC.,    DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •     HOLLYWOOD 


The  Concave  Screen 


DECENT  interment  rites  having  been 
observed  several  years  ago,  it  oc- 
casions no  little  surprise  that  some 
segments  of  the  projection  field  have 
again  interested  themselves  in  the  possi- 
bility of  correcting  certain  deficiencies 
in  the  projection  process  by  utilizing  a 
curved  screen.  So  alarming  is  this  re- 
newed interest  in  a  technological  corpse, 
that  we  hasten  to  deliver  another — and, 
we  hope,  final — graveside  sermon  over 
that  which,  it  was  thought,  had  long 
since  departed  this  world. 

The  curved  screen  was  sired  by  a  com- 
bination of  muddled  technical  thinking, 
smart  promotional  minds,  and  theatre 
owners  who  don't  know>  the  difference 
between  a  photocell  and  a  projection  lens. 
The  curved  screen  was  touted  as  ca- 
pable of  accomplishing  the  following 
chores:      (1)     correction    of    distortion; 

(2)  elimination  of  "hot  spot"  and  glare; 

(3)  creation  of  an  "illusion"  of  depth; 

(4)  improvement  of  sound  transmission; 

(5)  elimination  of  the  keystone  effect, 
and  (6)  the  screen  "could  be  washed  like 
glass". 

The  most  recent  curved  screen  is  com- 
posed of  two  surfaces  of  Fiberglas  (made 
by  Corning  Glass  Works)  :  the  first  sheet 
is  loosely  woven,  while  the  second  sur- 
face, two  inches  behind  the  first,  is  very 
tightly  woven.  Both  sheets  are  laced  to 
the  frame. 

The  passage  of  light  through  these  dis- 
similarly-woven surfaces  of  Fiberglas 
is  asserted  to  enhance  the  illusion  of 
depth  and  eliminate  screen  lines  and 
glare  by  diffusing  and  polarizing  the 
light.  Let's  see  about  this  and  other  as- 
sertions made  in  behalf  of  such  a  screen. 

1.    Screen  Image  Distortion 

Far  from  eliminating  distortion,  the 
curved  screen  creates  it!  To  patrons  sit- 
ting at  the  extreme  right  and  left  front 
seats  such  a  screen  does  appear  to  lessen 
distortion — but  this  is  only  because  parts 
of  the  screen  are  hidden  from  view  by 
the  curvature.  In  all  other  seats  through- 
out the  theatre  the  screen  creates  distor- 
tion. 

Because  the  screen  is  curved,  not  flat, 
horizontal  straight  lines  appear  bowed, 
while  vertical  straight  lines  are  variously 
curved,  depending  upon  the  camera  angle 
and  the  seat  from  which  the  screen  is 
viewed. 

Titles  shown  on  such  a  screen  come  up 
curved  instead  of  in  a  straight  line.  In 
the  case  of  vertical  straight  lines — for 
example,  a  microphone  stand  in  a  scene 
where  the  camera  is  "panned" — the  stand 
bends  like  a  bow,  alternately  bending 
and  bowing.  Projection  images  on  a 
curved  screen  distorts  the  focus,  because 


one  cannot  focus  on  a  single  plane. 

The  distortion  occasioned  by  the  loca- 
tion of  seats  too  far  over  at  either  side 
of  the  theatre  is  not,  optically  speaking, 
true  distortion  but  merely  the  familiar 
law  of  perspective.  Such  screens  as  have 
been  devised  in  an  attempt  to  compen- 
sate for  this  deficiency,  while  they  may 
add  to  the  illusion  of  naturalness,  can 
never  circumvent  the  laws  of  perspective. 

The  important  thing  to  remember  is 
that  this  type  of  "distortion"  is  not  true 
distortion  but  the  natural  perspective 
seen  when  viewing  anything  obliquely. 

2.    'Hot  Spot'  and  Glare 

In  front  projection  the  correction  of  a 
"hot  spot"  (so-called  because  of  a  con- 
centration of  light  within  a  spot  at  the 
center  of  the  screen  and  a  deficiency  of 
light  elsewhere  within  the  screen  area) 
is  definitely  not  a  function  of  any  screen, 
but  rather  is  it  solely  a  question  of  the 
optics  of  the  projector. 

As  to  glare,  a  curved  screen  produces 
more,  not  less,  glare. 


3.  Illusion  of  Depth 

No  data  advanced  by  the  proponents 
of  curved  screens — nor,  for  that  matter, 
nothing  in  the  literature  of  the  art  prior 
or  present — lends  any  credence  to  the 
assertion  that  a  curved  screen  contributes 
in  even  the  slightest  degree  to  an  en- 
hanced illusion  of  depth. 

4.  Sound  Transmission 

The  assertion  that  this  Fiberglas  screen 
improves  sound  transmission  is  just  not 
true,  and,  in  fact,  this  is  not  a  function 
of  any  type  screen.  All  screens  impair 
sound  transmission  to  a  certain  meas- 
urable extent,  and  the  Fiberglas  curved 
screen  is  neither  better  nor  worse  in  this 
respect. 

5.  The  Keystone  Effect 

Elongation  of  the  projected  image  is 
caused  by  steep  projection  angles.  The 
same  is  true  of  keystoning,  which  is  the 
widening  of  the  image  at  the  bottom  of 
the  screen,  with  its  characteristic  con- 
vergence of  vertical  lines  toward  the  top. 

These  deficiencies  could  be  corrected 


Projected  Light  and  the  Curved  Screen 

A  Lens  Manufacturer  Assays  the  Concave  Screen 

A  GOOD  projection  lens  is  designed  to  form  an  image  on  a  plane 
surface.  The  light  rays  contributing  to  the  formation  of  each  point 
on  such  image  (italics  ours — Ed.)  emerge  from  the  aperture  of  the 
projection  lens,  2  inches  or  so  in  diameter,  and  100  feet  or  more  away. 
The  cone  of  light  thus  formed  has  a  very  small  included  angle  and,  in 
consequence,  a  displacement  of  the  screen  a  few  inches  from  its  theo- 
retical plane  surface  would  have  little  or  no  visible  effect  upon  the  image 
quality. 

A  sufficiently  concave  screen  would  have  some  effect  upon  the  dis- 
tortion of  the  screen  image  when  viewed  from  a  position  to  the  extreme 
right  or  left  of  the  theatre.  Figures  on  the  far  side  of  the  screen  from 
the  observer  would  appear  somewhat  less  distorted,  since  the  viewing 
angle  would  be  less  acute;  those  on  the  near  side  would  appear  more 
distorted  (italics  ours)  ;  and  those  in  the  center  would  remain  unchanged. 
Whether  these  results  would  be  of  advantage  to  the  audience  we  cannot 
say. 

Very  much  open  to  question  in  our  mind,  however,  is  the  statement 
that  a  screen  composed  of  two  layers  would  add  anything  to  the  illusion 
of  depth  in  the  projected  image,  or  that  this  arrangement  would  polarize 
the  image  or  eliminate  glare;  but  we  are  willing  to  be  shown. 

This  matter  of  curved  screen  surfaces  would  need,  and  seems  worthy 
of,  much  more  thorough  investigation  and  some  tangible  information  if 
one  is  to  properly  evaluate  its  worth  or  lack  of  it.  Thus  far  the  pro- 
ponents of  such  screens  have  offered  nothing  that  would  provide  the  basis 
for  such  scientific  appraisal. 

It  appears  that  the  manufacturers  of  such  screens  consider  each 
installation  as  an  individual  problem  and  that  each  screen  must  be 
specially  designed  on  the  basis  of  width  of  theatre,  screen  size  and  length 
of  throw.  An  analysis  of  a  typical  situation  of  this  sort  and  of  the 
method  whereby  the  curvature  of  the  screen  is  computed  would  be  of 
considerable  interest  and  a  most  worthy  contribution  to  the  literature 
of  the  art. 


10 


INTERNATIONAL  PROJECTIONIST     •     January  194* 


somewhat  by  tilting  a  flat  screen  to  a 
suitable,  but  impractical,  angle,  but  the 
effect  anywhere  but  in  the  center  of  the 
theatre  is  usually  so  grotesque  as  to 
render  futile  any  such  course  of  action. 
A  curved  screen  cannot  eliminate  key- 
stoning  except  at  certain  places  where 
the  curvature  assumes  the  same  imprac- 
tical angle. 

6,    'Can  Be  Washed  Like  Glass' 

This  is  a  false  and  wholly  misleading 
statement.  With  ordinary  glass,  dirt 
which  gathers  on  the  surface  may  be 
rubbed  off.  The  curved  screen  under 
discussion  consists  of  a  grouping  of  glass 
threads  between  the  fibers  of  which  dirt 
collects.  As  with  any  fabric,  the  dirt  must 
be  washed  out  by  laundering. 

Because  this  Fiberglas  screen  depends 


for  sound  transmission  upon  small  pores 
in  its  weave — as  contrasted  with  the  large 
perforations  in  conventional  screens — 
it  is  definitely  a  dust  trap.  In  this  re- 
spect it  is  similar  to  the  earliest  sound 
screens,  which  were  woven  and  not  per- 
forated and  which  soiled  with  amazing 
speed. 

The  Fiberglas  screen  necessarily  would 
have  to  be  taken  down  frequently  and 
laundered ;  and  if  the  show  is  to  continue 
uninterruptedly,  the  theatre  would  have 
to  have  a  replacement  screen  available  or 
pay  overnight  laundering  charges.  This 
is  a  major  maintenance  problem. 

Thus  the  story  anent  the  curved  screen. 
IP  would  welcome  comment  from  any- 
body having  anything  interesting  to  say 
on  this  topic,  and  particularly  from  pro- 
jectionists who  have  used  or,  possibly, 
are  even  now  using  a  curved  screen. 


Historical  Sketch  of  Tv  Progress1 

By    L.    R.    LANKES 

Eastman   Kodak  Company 

This  is  a  brief  review  of  published  material  and,  in  its  original  form,  was  an  introductory 
part  of  a  symposium  on  the  various  aspects  of  Tv  which  will  affect  the  photographic  indus- 
try.   It  should  be  construed  as  an  attempt  to  convey  a  general  understanding  of  the  sub- 
ject by  considering  how  the  art  was  pieced  together. 


OF  ALL  the  pursuits  to  which  one 
can  turn  his  attention,  perhaps 
none  has  aroused  a  higher  degree  of 
curiosity,  enthusiasm,  and  hope  than  the 
development  of  television.  It  has  been 
said  that  television  holds  the  promise  of 
being  the  medium  that  can  bring  the 
peoples  of  far  places  emotionally  face 
to  face  with  one  another's  manners,  cus- 
toms, and  problems,  and  thereby  make 
them  understand  that  they  are  all  es- 
sentially human. 

It  could  be  said  that  the  motion  pic- 
ture also  holds  this  promise  since  Tv  is 
essentially  motion  pictures  with  radio 
as  the  means  of  conveyance.  However, 
there  may  be  advantages  in  Tv's  claim 
to  immediacy:  namely,  that  what  is  be- 
ing viewed  at  the  receiver  is  occurring 
now  at  the  transmitter. 

Tv  Concept  Not  Modern 

Contrary  to  general  opinion,  the  con- 
cept of  Tv  is  not  a  20-century  product. 
Even  in  Biblical  times  abstract  thinkers 
predicted  that  it  would  be  possible  to 
develop  the  ability  to  see  events  occur- 
ring beyond  the  horizon.  However,  the 
crystallization  of  specific  inventions 
which  led  to  Tv  as  we  know  it  today, 
began  with  the  transition  of  the  18th  to 
the  19th  century. 

The  first  items  are  Alexander  Volta's 
electric  battery,  the  voltaic  pile;  Profes- 
sor  Berzelius'   isolation    of   the    element 


t  J.  Soc.  Mot.  Pict.  Eng.,  September,  1948,  p.  223. 


selenium;  Oersted's  discovery  of  the 
principle  of  electromagnetic  induction; 
and  the  efforts  of  Ampere,  Ohm,  and 
Faraday. 

The  middle  of  the  19th  century  might 
be  said  to  have  borne  the  infant,  Tv, 
for  in  1842  Alexander  Bain,  an  English 
physicist,  first  proposed  a  device  to  send 
pictures  from  one  place  to  another  by 
electric  wires.  Bain's  plan  was  so  cor- 
rect basically  that  it  embraced  the  fun- 
damentals of  all  picture  transmission, 
having  recognized  the  particular  prob- 
lems posed  by  the  need  for  synchroniza- 
tion between  transmitter  and  receiver. 

The  'Copying  Telegraph'  of   1847 

In  1847,  Bakewell  devised  a  "copying 
telegraph"  employing  an  elementary 
scanning  device.  Specifically,  this  was 
an  instrument  for  transmitting  writing 
or  drawings  in  the  form  of  non-conduct- 
ing shellac  ink  on  tin  foil.  The  foil  was 
then  wrapped  around  a  cylinder  which 
rose  as  it  rotated,  thereby  tracing  out  a 
spiral  with  a  fixed  metal  needle  press- 
ing against  the  foil.  At  the  receiver,  a 
similar  cylinder  was  covered  with  chemi- 
cally treated  paper.  In  1862,  Abbe 
Caselli  transmitted  the  first  electric  pic- 
ture from  Amiens  to  Paris. 

The  latter  part  of  the  19th  century 
saw  the  groundwork  for  the  construction 
of  the  present  video  industry.  The  light- 
sensitive  properties  of  selenium  were  dis- 
covered in  1873  by  a  telegraph  operator 
named  May.    In   a  terminal   station  for 


the  Atlantic  cable  on  the  coast  of  Ire- 
land, May  observed  the  effect  of  sun- 
light falling  on  selenium  resistors  in 
some  of  his  circuits.  This  indicated  that 
light  values  can  be  converted  into 
equivalent  electrical  values. 

In  1875,  G.  R.  Carey,  in  Boston,  and 
Ayrton  and  Perry,  in  England,  proposed 
to  build  a  large  mechanical  eye  using  a 
plate  of  tiny  selenium  cells  as  the  retina. 
Each  cell  would  be  connected  by  wire 
to  a  corresponding  spot  on  the  receiver. 
Electromagnets  connected  to  each  of  the 
small  sections  of  the  receiver  plate  were 
to  regulate  the  amount  of  light  on  each 
section. 

Cathode  Rays,  Photoelectric  Effect 

Many  other  suggestions,  all  very  simi- 
lar in  principle,  were  advanced  through 
this  period.  These  were  followed  by  Sir 
William  Crookes'  discovery  of  cathode 
rays  in  his  famous  vacuum  tube.  In 
1880,  Leblanc  developed  the  complete 
principle  of  scanning  wherein  a  picture 
is  divided  into  lines  and  each  line  into 
tiny  segments.  Hertz,  in  1886,  confirmed 
Maxwell's  theories  of  electricity  and 
discovered  the  photoelectric  effect  in 
1887,  when  he  noticed  that  a  spark  could 
be  made  to  jump  over  a  gap  more  readily 
if  one  of  the  electrodes  were  illuminated 
than  if  the  event  occurred  in  darkness. 
The  German  Hallwachs  later  studied 
the  photoelectric  effect  systematically 
and  concluded  that  light  set  free  elec- 
trical particles  from  the  electrode  sur- 
face. Sir  J.  J.  Thompson  identified  them 
as  electrons,  and  Einstein  announced  the 
theory  of  the  photoelectric  effect. 

The  practical  side  was  advanced  by 
Elster  and  Geitel  who,  as  early  as  1890, 
built  practical  photoelectric  cells.  Thus 
the  method  was  defined  by  which  a  Tv 
camera  would  turn  a  picture  into  elec- 
tricity. 

As  a  noteworthy  aside,  Thomas  Edison 
filmed  his  first  motion  picture  in  1889; 
and  Marconi,  in  1895,  sent  and  received 
his  first  wireless  signals  across  his 
father's  estate. 

The  Nipkow  Scanning  Disk 

Coincidental  with  these  latter  develop- 
ments came  the  invention,  in  1884,  by 
the  German  Nipkow  of  the  rotating 
scanning  disk.  This  disk  made  use  of 
the  very  significant  technique,  previously 
suggested,  of  dissecting  the  scene  to  be 
transmitted  into  points  of  light  which 
would  then  be  measured  on  a  time  scale 
in  orderly  fashion.  Nipkow's  work  ranks 
high  in  the  history  of  the  medium  be- 
cause he  realized  so  early  a  system 
which  was  not  improved  upon,  basically, 
for  nearly  50  years. 

In  1890,  the  Englishman  Sutton  pro- 
posed a  system  for  a  Tv  receiver  which 
ranks  in  importance  with  Nipkow's  sys- 
(Continued  on  page  26  I 


INTERNATIONAL  PROJECTIONIST 


January  1949 


II 


Emphasis  on  the  Port  Side  bv  a  buckley 


SINCE  light  is  the  essence  of  motion 
picture  projection,  the  various  factors 
in  its  production  and  transmission  are 
of  great  importance.  To  deal  with  one 
or  two  links  in  the  transmission  of  light 
from  its  source  to  the  eyes  of  the  audience 
and  ignore  other  factors  is  the  height  of 
futility.  Apart  from  the  questions  of 
correct  carbons,  arc  wattage  and  mechan- 
ical efficiency,  the  salient  points  in  the 
optical  train  are: 

1.  Light  source. 

2.  Reflector  or  condenser  system. 

3.  Projection  lens. 

4.  Port  medium. 

5.  Theatre  atmosphere. 

6.  Screen  efficiency. 

With  the  exception  of  item  4,  these 
links  in  the  projection  chain  have  been 
discussed  repeatedly  by  specialists  in 
each  sphere.  It  is  to  be  regretted  that 
the  port  medium  has  not  always  been 
recognized  as  a  vital  link  in  the  efficient 
transmission  of  optical  images  from  the 
film  gate  to  the  screen  and  thus  has 
seldom  received  close  attention.  Let  us, 
therefore,  discuss  a  few  details  relative 
to  this  important  element  in  projection. 

Essential  Requirements  for  Ports 

The  simple  but  essential  requirements 
for  projection  ports  are: 

a.  It  shall  be  of  the  correct  size  and 
thickness. 

b.  Its  surface  shall  be  perfectly  plane, 
highly  polished,  and  free  from 
scratches  or  other  marks. 

c.  No  distortion  or  color  shall  be  pres- 
ent in  the  medium. 

d.  The  surface  of  the  medium  shall  be 
at  exact  right  angles  to  the  optical 
axis. 

e.  The  medium  shall  be  scrupulously 
clean. 

The  requirements  for  an  observation 
port,  while  not  so  critical,  still  are  of 
great  importance.     Here  they  are: 

a.  It  shall  be  of  sufficient  size  to  permit 
an  unobstructed  view  of  the  screen 
from  a  position  midway  between  the 
rear  of  the  arc  lamp  and  the  front 
of  the  projector. 

b.  No  reflection  from  the  rear  wall 
shall  be  visible  in  the  port  medium, 
and 

c.  No  color  content  or  distortion  shall 
be  present  in  the  medium. 

Standardization  of  Sizes 

These  requirements,  reasonable  though 
they  be,  are  not  commonly  met.  Not 
only  are  ports  of  the  wrong  sizes  and 
spaeings,  but  any  kind  of  glass,  irrespec- 
tive of  quality,  very  often  finds  its  way 
into  the   port  apertures. 

Since  a  projector  is  a  fixed  object, 
there  is  little  point  in  having  an  extremely 


large  projection  port  except  where  a  slide 
lantern  snares  the  same  aperture.  While 
the  medium  must  be  larger  than  the 
projected  image,  there  seems  to  be  little 
reason,  except  in  extreme  cases,  for  using 
a  port  12  x  12  inches  for  the  transmission 
of  an  image  4x3  inches. 

For  various  reasons,  particularly  clean- 
ing purposes,  the  projection  port  medium 
should  be  fitted  on  the  inside  of  the 
dividing  wall,  and  the  size  (actual  glass 
area)  should  rarely  exceed  6  x  4%  inches 
for  one  projector.  Where  the  medium 
is  fitted  to  the  auditorium  side  of  the 
dividing  wall  it  must,  of  course,  be  a 
little  larger,  but  in  any  event  very  little 
larger  than  the  picture  image. 

Observation  ports,  on  the  other  hand, 
are  rarely  large  enough  for  convenience 
and  ease  of  screen  viewing.  Projection- 
ists are  not  fixed  objects;  they  must  move 
about  a  little  and  be  able  to  see  the 
complete  screen  from  more  than  one  posi- 
tion. It  should  not  be  necessary  to  hold 
one's  face  close  to  the  glass  in  order  to 
see  the  full  width  and  height  of  the 
screen. 

The  solid  angle  existing  between  the 
lens  and  the  screen  determines  the  mini- 
mum size  to  permit  adequate  observation, 
and  it  is  suggested  that  no  observation 
port  (again,  actual  glass  area)  be  less 
than  10  x  7V2  inches,  nor  larger  than 
12  x  9  inches. 


Projectionists  agree  almost  unanimous- 
ly that  a  spacing  of  five  feet  between  the 
optical  axes  of  two  regular  projectors  is 
a  reasonable  one:  this  allows  ample 
working  space  for  operation,  cleaning, 
lubrication  and  service.  For  a  level,  or 
nearly  so,  projection  angle,  the  optical 
axis  should  be  at  a  height  of  approxi- 
mately 4%  feet  from  the  floor  level,  de- 
pending upon  the  degree  of  projector 
angle  (Table  1). 

With  more  acute  angles  of  positive  and 
negative  angle,  the  height  of  the  port 
will  vary  somewhat.  As  the  average  eye 
level  is  slightly  more  than  five  feet  from 
the  floor,  the  center  of  the  observation 
port  should  be  about  five  feet  high,  cir- 
cumstances permitting.  The  displacement 
between  the  centers  of  the  projection  and 
companion  observation  ports  should  be 
about  18  inches. 

Suitable  Medium  for  Ports 

From  the  early  days  of  motion  pictures, 
glass,  in  some  form  or  other,  has  been 
the  universal  medium  for  projection  and 
observation  ports.  More  recently,  plastic 
sheet  has  been  tried,  but  since  its  surface 
is  so  easily  scratched  or  damaged,  it  does 
not  compare  favorably  with  glass. 

One  notable  point  about  plastic,  how- 
ever, is  that  dust  appears  to  be  repelled 
by  electrostatic  charges  in  the  material. 
Glass,  on  the  other  hand,  seems  to  attract 


TABLE  1.   Approved  Method  for  Locating  Projector  Port 
h  =  H  +  rA  -  DB 


Projec- 

tion 

Angle0 

A 

B 

0 

1.00 

0.00 

2 

1.00 

0.04 

4 

1.00 

0.07 

6 

1.01 

0.11 

8 

1.01 

0.14 

10 

1.02 

0.18 

12 

1.02 

0.21 

14 

1.03 

0.25 

16 

1.04 

0.29 

18 

1.05 

0.33 

20 

1.06 

0.36 

22 

1.08 

0.40 

24 

1.09 

0.45 

26 

1.11 

0.49 

28 

1.13 

0.53 

30 

1.16 

0.58 

H  is  the  height  of  the  center  of  the  projector  pivot  from  the  floor;  r  is  the 
radial  distance  of  the  optical  centerline  above  the  center  of  the  pivot;  D  is  the 
distance  of  the  center  of  the  pivot  from  the  front  wall  of  the  projection  room; 
(f>  is  the  angle  of  projection ;  and  h  is  the  required  height  of  the  center  of  the  port 
from  the  floor  of  the  projection  room.  Select  the  values  of  A  and  B  corresponding 
to  the  angle  of  projection,  and  substitute  in  the  formula. 


12 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


IIIIIIIU- 

When  We  Say 

MAXIMUM 
We  Mean 

MAXIMUM! 


STRONG  MOGUL 

PROJECTION  ARC  LAMP 

projects  15,000  lumens— the  MAXIMUM  light  that  film  will 
accept  without  damage! 

BRIGHTEST  POSSIBLE  PICTURE 
ON  THE  BIGGEST  SCREENS 

CUk&K-t/ie  famfia  <m  STRONG  -tAepic&te  u  tuffa/    J 


FOR  TWICE  THE   LIGHT  ON  SCREENS  UP  TO   18   FEET 

THE  STRONG  UTILITY   1    KW.   HIGH   INTENSITY 

PROJECTION    ARC    LAMP 

There  are  more  Strong-made  D.C.  1  KW.  lamps  used  today  than  all 
other  makes  of  1    KW.  lamps  combined. 

THE  WORLD'S  LARGEST  MANUFACTURER  OF  PROJECTION  ARC 
LAMPS.  Strong  Lamps  are  the  ONLY  Projection  Lamps  Produced 
Complete  Within  One   Factory. 


Use   this    Coupon   Today   for    DEMONSTRATION    or    LITERATURE 

THE  STRONG  ELECTRIC  CORPORATION 

87  CITY  PARK  AVENUE  TOLEDO  2,  OHIO 

□  I    would    like    a    demonstration    of    Strong    lamps    in    my    theatre, 
without  cost  or  obligation. 

□  Please   send   free    literature    on  the: 

□  Mogul  Lamp  □   Utility  Lamp 

□  Strong  Rectifiers  □  Strong   Reflectors 

□  Strong   Arc   Spotlamps 

NAME      


THEATRE      

STREET    

CITY   and   STATE 


INTERNATIONAL  PROJECTIONIST 


January  1949 


lii 


every  airborne  particle  of  dust  and  flufi. 
We  shall  therefore  confine  our  observa- 
tions to  glass,  good  or  bad. 

Apart  from  meeting  statutory  require- 
ments relative  to  smoke  and  fire,  the  port 
glass  serves  to  prevent  mechanical  noise 
from  the  projection  room  reaching  the 
auditorium.  Its  most  important  role, 
however,  is  to  transmit  an  undistorted 
image  from  the  lens  to  the  screen. 

In  this  process  (a)  the  light  loss  should 
be  slight;  (b)  there  should  be  no  trace 
of  distortion  in  the  glass;  (c)  the  faces 
of  the  glass  should  be  perfectly  parallel 
and  plane,  and  (d)  the  reflection  on  the 
projection  room  side  of  the  glass  should 
be  as  low  as  possible. 

Window  glass,  sometimes  used,  is  en- 
tirely unsuitable  for  this  purpose.  It  is 
too  thin,  possesses  color  content,  and  is 
responsible  for  image  distortion.  Plate 
glass,  while  usually  of  good  quality  and 
free  from  distortion,  has  a  fairly  large 
transmission  loss.  Its  reflectivity,  how- 
ever, is  understood  to  be  lower  than  true 
optical  glass. 

Type  of  Glass;  Light  Transmission 

When  using  plate  glass,  quite  a  large 
percentage  of  light  loss  can  be  expected, 
even  when  the  glass  is  clean.  The  addi- 
tional losses  when  dust,  and  maybe 
grease,  are  present  cannot  be  accurately 
estimated. 

Optical  glass  does  not  distort:  it  trans- 
mits a  perfect  image,  but  its  surface  is 
so  highly  polished  that  increased  reflec- 
tion takes  place.  It  is  suggested  that  this 
reflection  could  be  minimized  by  surface 
treating,  but  here  difficulties  might  arise 
regarding  the  satisfactory  cleaning  of  its 
surface. 

From  elementary  observations  of  re- 
fraction through  glass  it  is  known  that 
when  light  rays  meet  the  glass  at  exact 
right  angles  they  pass  straight  through 
the  glass,  i.e.,  there  is  no  displacement. 

When,  however,  light  rays  meet  the 
glass  surface  at  any  other  angle,  the  rays 
are  bent  towards  the  normal  as  they  pass 
through  the  glass;  while  on  emergence 
they  then  take  up  a  similar,  but  displaced, 
course.  Now,  since  the  modern  projec- 
tion lens  is  indeed  a  precision  instrument 
— exact  glass  combinations,  finite  spac- 
ings  and  extreme  accuracy  throughout — 
clearly  many  of  these  desirable  points  are 
neutralized  to  some  extent  by  incorrectly- 
angled  port  glasses. 

The  foregoing  observations  indicate 
that  to  obtain  maximum  efficiency  the 
plane  surface  of  the  glass  should  be  at 
exact  right  angles  to  the  optical  axis  of 
the  projector. 

When  using  certain  types  of  arc  lamps 
much  stray  light  occurs  on  the  rear  wall 
of  the  projection  room.  Very  often  this 
defect  has  been  minimized  by  tilting  the 
observation  port  up  or  down.  It  is  sug- 
gested, however,  that  the  real  cure  is  for 


an  asbestos  curtain  or  specially  designed 
metal  sheet  to  be  placed  at  the  rear  of 
such  a  lamp;  the  port  glass  can  then  be 
fitted  so  that  a  better  screen  image  may 
be  seen. 

Proper  Maintenance  of  Ports 

The  necessity  for  cleaning  projection 
and  observation  ports  is  a  point  very 
often  overlooked  by  architects  and  others. 
To  anyone  not  well  versed  in  the  art,  the 
port  glass  is  often  a  minor  point  in  the 
general  projection  scheme.  That  is  why, 
not  infrequently,  any  old  piece  of  window 
glass,  or  even  worse,  is  immovably  fixed 
on  the  auditorium  side  of  the  dividing 
wall. 

In  many  cases  steps  or  ladders  must  be 
used  to  make  some  pretense  of  cleaning 
them.  Any  projectionist  would  tear  his 
hair  at  the  thought  of  such  an  idea;  but 


often  he  has  no  control  over  the  matter 
and  he  must  make  his  daily  journey  up 
the  ladder  and  attempt  to  clean  them. 
Often  he  may  even  forget  to  do  so. 

The  projection  engineer  will  rightly 
insist  that  projection  and  observation 
ports  be  fitted  in  metal  frames,  so  that 
they  can  instantly  be  detached  for  clean- 
ing. He  will  also  specify  true  optical 
glass  of  the  regulation  thickness.  The 
intelligent  projectionist  will  devote  ex- 
actly the  same  attention  to  his  port  glass 
that  he  gives  to  his  lens — correct  and 
frequent  cleaning  treatment. 

If  these  notes  serve  to  awaken  an  in- 
terest in  the  real  importance  of  the  port 
glass  and  its  function — perhaps  to  many 
who  have  long  regarded  this  unit  as  a 
necessary  evil — it  will  have  served  its 
purpose.  Any  port  might  do  in  a  storm, 
but  certainly  not  in  a  projection  room. 


Sound  Kodascope  FB-40  Projector  Again  Available 


THE  most  powerful  of  Kodak's  line  of 
16-mm  sound  projectors — the  Sound  Ko- 
dascope FB-40 — is  again  available  after  an 
absence  of  several  years.  Extremely  simple 
to  operate  and  control,  it  produces  large, 
clear,  smooth-running  movies,  accompanied 
by  undistorted  sound  from  the  film  track, 
from  records,  or  from  a  microphone. 

The  amplifying  system  has  a  full  40-watt 
capacity,  which  reserve  power  adds  to  the 
effectiveness  of  undistorted  sound  in  pro- 
jection. True  pitch,  especially  important 
in  the  reproduction  of  music,  is  maintained 
by  the  use  of  an  oil-coupled  flywheel  on 
the  sound  drum  shaft.  Also  utilized  is 
Kodak's  exclusive  built-in  fidelity  control 
which  permits  accurate  focus  of  the  scan- 
ning beam  on  either  surface  of  the  film,  thus 
assuring  equally  excellent  sound  with  either 
original  or  duplicate  films. 

The  projector  is  supplied  with  a  twin  12- 
inch  speaker  unit,  more  than  adequate  to 
handle    the    40-watt    output    provided.     The 

The     Kodascope     FB-40    sound-film     projector 
again  made  available  by  Eastman   Kodak. 


unit,  when  closed,  forms  a  compact,  easily 
portable  case  and,  when  opened,  the  speak- 
ers may  be  operated  together  at  an  angle 
or  separated  by  several  yards  for  best  au- 
dience coverage.  Twenty-five-  and  50-foot 
lengths  of  2-wire  speaker-to-speaker  exten- 
sion cord  are  available  as  accessories. 

Many   Unusual  Operational  Features 

An  unusual  feature  is  twin  jacks,  with 
separate  controls,  on  the  amplifier  so  that  a 
microphone  and/or  a  phonograph  recording 
may  be  plugged  in  to  provide  sound  in  con- 
junction with  silent  films.  The  microphone 
and/or  phonograph  may  also  be  used  with 
the  sound  track  of  sound  films  if  it  is  de- 
sired to  add  a  running  commentary  or  spe- 
cial music.  The  system  may  also  be  used 
for   public    address   purposes. 

The  projector  operates  from  within  its 
own  carrying  case,  and  the  detachable  upper 
section  of  the  case  provides  a  projection 
stand  supported  on  four  sturdy,  rubber- 
tipped  feet,  which  can  be  placed  on  any 
table.  With  the  operating  side  of  the  case 
open,  everything  required  for  normal  sound- 
film  operation  is  within  easy  reach. 

A  lumenized  Kodak  projection  Ektanon 
2-inch,  f/1.6  Lens  is  standard  equipment 
with  the  projector.  However,  five  inter- 
changeable accessory  lenses,  ranging  from 
a  I-inch,  f/2.5  wide  angle  to  a  4-inch,  f/2.5 
lens  for  maximum  distance  throws,  may  be 
obtained  separately.  A  1600-foot  reel  is 
provided,  although  the  reel  arm  will  accom- 
modate reels  holding  up  to  2000  feet. 

The  projector  is  designed  for  110-125-volt, 
60-cycle  a-c  operation.  A  100-foot  long  cable 
for  connecting  speaker  and  projector  is  also 
provided.   Additional  cable  may  be  obtained. 


Filter  Changes  Color,  Not  Intensity 

A  new  filter  which  is  fitted  over  photo- 
flood  lamp  reflectors  has  been  developed  by 
Acme-Lite  Mfg.  Co.,  Chicago.  Trade-named 
"Litefilter,"  the  device  is  said  to  filter  out 
destructive  yellow  and  red  light  rays.  By  its 
use  the  color  and  character  of  the  light  is 
changed  without  reducing  light  intensity. 


14 


INTERNATIONAL  PROJECTIONIST 


January  1949 


Ultrafax:  New  Communications  Marvel 


j  I LTRAFAX,  a  newly  developed  system 
Uof  television  communications  capable 
of  transmitting  and  receiving  written  or 
printed  messages  and  documents  at  the 
rate  of  a  million  words  a  minute,  was 
demonstrated  publicly  for  the  first  time 
by  RCA  at  the  Library  of  CongTess, 
Washington,  D.  C,  on  October  21. 

The  development,  which  splits  the  sec- 
onds and  utilizes  each  fraction  for  high- 
speed transmission  of  intelligence,  is 
held  to  be  as  significant  a  milestone  in 
communications  as  was  the  splitting  of 
the  atom  in  the  world  of  energy. 

Among  the  possible  developments  of 
this  new  system  are  the  following: 

Possible  Uses  of  the  System 

1.  The  exchange  of  international  tele- 
vision programs  achieved  on  a  trans- 
oceanic basis. 

2.  A  service  of  television  and  Ultrafax 
by  which  the  same  receiving  set  would 
bring  various  types  of  publications  into 
the  home,  or  a  newspaper  for  that  matter, 
without  interrupting  the  program  being 
viewed. 

3.  A  system  of  world-wide  military 
communications,  scrambled  to  the  needs 
of  secrecy,  which  with  ten  transmitters 
could  carry  in  60  seconds  the  peak  load 
of  message  traffic  cleared  from  the  Penta- 
gon Building  in  24  hours  during  World 
War  II. 

4.  The  establishment  of  great  news- 
papers as  national  institutions  by  in- 
stantaneous transmission  and  reception 
of  complete  editions  into  every  home 
equipped  with  a  television  set. 

5.  The  transmission  of  a  full-length 
motion  picture  from  a  single  negative  in 
the  production  studio  simultaneously  to 
the  screens  of  thousands  of  motion  pic- 
ture theatres  throughout  the  country. 

6.  The  possibility  of  a  new  radio-mail 
system  with  the  vast  pickup  and  delivery 

Lorraine  Carbon  Designation 

The  designation  of  Lorraine  carbons 
as  "French  carbons"  is  misleading  and 
has  given  rise  to  numerous  misconcep- 
tions regarding  the  physical  character 
and  performance  of  the  Lorraine  product, 
according  to  Edward  Lachman,  president 
of  Carbons,  Inc.,  distributors  for  the 
U.  S.  A.  Especially  prevalent  is  the 
identification  of  the  Lorraine  with  the 
old  Sun-Arc  carbons  which  were  sold  in 
the  U.  S.  in  pre-war  years,  said  Lachman, 
who  asserts  that  Sun-Arc  carbons  are  no 
longer  being  manufactured. 

Regarding  inquiries  as  to  the  available 
supply  of  Lorraine  carbons  in  this  coun- 
try, Lachman  emphasized  that  an  ample 
supply  of  all  trims  is  warehoused  at 
Boonton,  N.  J.,  and  that  all  orders,  irre- 
spective of  quantity  or  type  of  carbon, 
are  accorded  immediate  delivery. 


services  of  the  Post  Office  Department. 

The  demonstration  proved  the  ability 
of  Ultrafax  to  transmit  at  the  speed  of 
light — 186,000  miles  a  second — a  wide 
variety  of  graphic  material  including 
charts,  fingerprints,  news  and  advertising 
layouts  and  items  ranging  from  historical 
documents  to  complex  atomic  formulae 
and  battle  maps. 

A  striking  feature  of  the  demonstration 
came  when  the  1047-page  novel  "Gone 
With  the  Wind"  was  transmitted  word 
for  word  in  its  entirety  in  about  two  min- 
utes from  the  transmitter  to  the  receiver 
in  the  Library  of  Congress. 

During  the  demonstration,  messages, 
technical  drawings  and  other  material  in 
foreign  languages  were  among  the  nu- 
merous items  transmitted  by  Ultrafax 
directly  from  the  tower  of  the  NBC's 
television  station  WNBW  at  the  Ward- 
man  Park  Hotel  through  the  air  to  a 
receiving  terminal  on  the  stage  of  the 
Library  of  Congress,  a  distance  of  three 
miles.  In  a  regular  service  the  transmis- 
sions could  be  radio-relayed  any  distance 
across  the  country,  using  the  commercial 
radio-relay  system  towers  which  now  are 
being  erected  to  establish  national  tele- 
vision networks. 

Motion  Picture  Distribution 

Said  David  Sarnoff,  RCA  board  chair- 
man: "It  is  now  within  the  compass  of 
one's  imagination  to  foresee  the  day, 
when  through  television  and  Ultrafax,  a 
radio     newspaper     may     be     delivered 


through  the  air  into  every  home  equipped 
with  a  television  set.  It  would  be  possible 
to  have  the  same  transmitter  that  broad- 
casts the  television  program  simultane- 
ously broadcast  the  radio  newspaper.  In 
fact,  the  same  home-receiver,  with  proper 
attachments,  could  print  the  newspaper 
even  without  interrupting  the  program 
being  viewed." 

Further,  he  said  it  seems  only  reason- 
able to  expect,  as  the  present  system  of 
Ultrafax  progresses,  that  it  may  be  pos- 
sible to  transmit  full-length  motion  pic- 
tures from  a  single  negative  in  the 
production  studio  simultaneously  to  the 
screens  of  thousands  of  theatres  through- 
out the  country.  This,  he  added,  would 
provide  a  new  system  of  motion  picture 
distribution. 

Principal  Transmitting  Steps 

"We  can  foresee  the  day,"  he  contin- 
ued, "when  Ultrafax,  which  includes  tele- 
vision and  radio  relays,  can  provide  us 
with  a  new  service  of  international  tele- 
vision. But  first,  an  'airlift'  must  be  pro- 
vided across  the  Atlantic.  Even  now  by 
the  use  of  12  to  14  suitably  equipped 
communication  planes  flying  over  the 
ocean  and  properly  spaced,  an  overseas 
airborne  radio-relay  system  could  be  es- 
tablished between  the  U.  S.  A.  and  Eu- 
rope that  would  provide  not  only  an  ex- 
change of  television  programs,  but  also 
handle  the  equivalent  of  tons  of  mail, 
news  and  other  services  which  Ultrafax 
makes  possible." 

Ultrafax's  remarkable  speed,  the  engi- 
neers explained,  is  possible  because  full 
pages  of  information  are  transmitted  as 


-MICROWAVE  BEAM 


Simplified   diagram   of   a   complete    Ultrafax   system,   showing   the   principal    elements 
which   make    possible    the   million-words-a-minute    transmission    speed    of    this    newly- 
developed  means  of  communication.  The  transmission  of  motion  pictures  by  this  method 
is  a  definite  possibility,  according  to  the  RCA  development  engineers. 


INTERNATIONAL  PROJECTIONIST 


January  1949 


15 


television  pictures  at  the  rate  of  fifteen 
to  thirty  a  second.  The  principal  steps 
in  the  Ultrafax  process  are: 

1.  Preparation  of  data  to  be  trans- 
mitted, to  assure  a  continuous  flow  at 
high  speed. 

2.  Scanning  of  this  data  by  what  is 
known  as  a  flying-spot  television  scanner, 
at  the  sending  terminal. 

3.  Transmission  of  the  television 
image  as  ultra-high  radio-frequency  sig- 
nals over  a  microwave  relay  system. 

4.  Reception  on  projection-type  tele- 
vision kinescope,  or  "picture  tube,"  from 
which  incoming  messages  are  recorded  on 
motion  picture  film,  or  ultimately  directly 
onto  photographic  paper. 

At  the  end  of  a  transmission,  the  ex- 


posed film  can  be  transferred  quickly  to 
a  special  processing  unit  developed  by 
Kodak.  The  film  is  passed  through  a 
miniature  developing  tank,  rinsed  and 
fixed  in  less  than  15  seconds  and  dried  in 
25  seconds  more.  This  unit,  regarded  as 
an  important  advance  in  photographic 
art,  resulted  from  advance  equipment 
built  for  the  armed  services  during  the 
war. 

The  Ultrafax  film  may  be  enlarged  to 
full-sized  copy  by  means  of  a  high-speed 
continuous  processing  machine.  The 
equipment  is  similar  to  that  used  during 
the  war  for  V-mail  enlarging.  There  is 
no  limit  to  the  number  of  Ultrafax  mess- 
ages which  may  be  printed  from  a  single 
film. 


From  the  Production  Front 


Expanding  Use  of  Infra-Red   Film 

By  ARCHIE  STOUT,  ASC 


THE  NATION'S  movie  critics  who  have 
been  so  generous  with  praise  for  the 
photography  in  "Fort  Apache,"  and  the 
millions  of  moviegoers  who  have  seen 
the  film  to  date,  probably  do  not  know 
that  a  total  of  10,000  feet  of  infra-red 
film  went  into  making  the  dramatic  out- 
door sequences  that  mark  the  picture.  In 
all  probability  there  is  more  actual  infra- 
red footage  in  "Fort  Apache"  (2,800 
feet  in  the  final  cutting),  than  in  any 
other  theatrical  production  released  to 
date. 

The  uses  for  infra-red  film  are  as  varied 
as  the  types  of  present-day  pictures.  It 
affords  the  progressive  cinematographer 
many  opportunities  to  achieve  striking 
dramatic  and  pictorial  effect  shots  that 
can  be  made  in  no  other  way.  At  the 
same  time,  it  permits  carrying  on  smooth 
continuity  of  photography  by  using  the 
same  film  in  medium  and  closeup  shots. 

John  Ford's  "Fort  Apache,"  with  so 
much  of  its  action  laid  in  the  pictorially 
beautiful  region  of  the  great  Southwest, 
was  particularly  suited  to  the  use  of  infra- 
red film.  The  vast  expanse  of  blue,  cloud- 
flecked  sky,  when  emphasized  by  use  of 
this  film  and  filters,  provides  a  dramatic 
backdrop  for  the  story's  teeming  action. 

Most  Advantageous  Lighting 

Normally,  I  found  that  the  most  advan- 
tageous light  conditions  for  shooting 
infra-red  is  a  cross  or  slightly-front  cross 
light,  using  a  stop  of  f/5.6  to  f/8  and  a 
25A  filter.  Of  course,  this  is  not  a  definite 
rule,  but  will  give  a  working  start  that 
your  test  box  can  prove  or  disprove  in  ten 
minutes,  and  result  in  making  correc- 
tions to  suit  one's  needs. 

It  may  be  interesting  to  note  that  the 


dawn  sequence  in  "Fort  Apache"  in  which 
the  troops  are  seen  moving  across  the 
desert  was  shot  while  a  light  rain  was  in 
progress,  using  a  29F  filter  and  a  stop  of 
f/3,  indicating  that  the  film  is  not  re- 
stricted to  use  only  in  brilliant  sunshine. 

Probably  the  reason  more  directors  of 
photography  have  not  used  infra-red  film 
more  often  is  the  fact  that  much  of  the 
first  infra-red  was  marked  by  unstable 
balance.  For  example,  two  rolls  of  early- 
day  infra-red  film  shot  at  the  same  f/  stop 
and  under  the  same  conditions — and 
witliin  an  hour — would  have  a  very  wide 
difference  in  density,  so  much  so,  that 
they  would  be  practically  unusable.  Such 
hazards  do  not  prevail  with  present  day 
infra-red  film.  The  density  of  the  10,000 
feet  used  in  "Fort  Apache"  remained 
quite  constant  throughout. 

Other  cinematographers  may  be  inter- 
ested in  pertinent  facts  concerning  this 
far  too  little  used  film  stock,  some  of 
which  were  obtained  only  after  consider- 
able trial  and  error. 

Makeup  Changes  Indicated 

In  shooting  closeups  in  which  players 
appear,  a  very  light  brown  makeup  should 
be  used  in  combination  with  dark  brown 
rouge  for  the  lips,  instead  of  the  cus- 
tomary red.  The  brown  makeup  prevents 
"chalking"  of  the  features.  In  "Fort 
Apache,"  no  makeup  of  any  kind  was 
used  except  in  the  infra-red  shots. 

The  shades  of  brown  makeup  will  vary 
with  the  filter  used,  which  should  be  a 
23A,  25A,  and,  rarely,  a  29F.  Choice  of 
filter  will  depend  entirely  on  the  back- 
ground, sky  and  clouds.  In  several  in- 
stances I  used  a  23A  filter  and  then  shot 
the  scene  to  follow  using  a  29F  filter, 


and  succeeded  in  maintaining  a  balanced 
density  in  both  long  shot  and  closeup. 

In  using  only  the  red  filters  it  is  well 
to  remember  that  all  reds  in  the  scene 
are  consequently  highlighted  in  color  and 
with  a  corresponding  degree  according  to 
the  filter  used.  All  props  normally  con- 
taining red,  such  as  flags,  insignia,  etc., 
should  be  replaced  with  duplicates  in 
which  the  red  colors  have  been  replaced 
by  light  or  medium  brown,  and  the  filters 
for  the  shot  carefully  selected. 

In  balancing  connecting  shots,  the  sky 
should  also  come  in  for  careful  evalua- 
tion in  the  selection  of  filter  to  be  used 
for  long  and  close  shots.  A  ground  haze 
can  cause  serious  trouble  if  shot  in  a 
backlight  or  back  cross-light.  Where 
haze  prevails,  a  few  test  shots  developed 
on  the  spot  will  indicate  the  best  filter 
to  use,  and  at  the  same  time  convince 
you  of  the  value  of  infra-red  film  for  get- 
ting dramatic  pictorial  effects  that  would 
not  be  possible  under  the  same  condi- 
tions with  any  other  emulsion. 

Application  to  16-mm  Field 

For  the  16-mm  moviemaker,  amateur  or 
professional,  infra-red  film  offers  many 
possibilities,  both  pictorial  and  time-sav- 
ing. Where  the  filmer  has  not  the  lighting 
facilities  to  photograph  actual  night 
shots,  infra-red  and  filters  will  enable  him 
to  photograph  such  shots  in  daylight.  The 
16-mm  professional  will  find  many  uses 
for  the  film  to  enhance  production  val- 
ues— something  he  can  easily  prove  by 
making  a  few  test  shots. 

There  is  no  definite  emulsion  speed 
indicated  for  infra-red  film  for  use  in 
daylight.  Recently  I  contacted  Eastman's 
representative,  who  was  visiting  in  Hol- 
lywood, but  could  get  no  definite  infor- 
mation regarding  this. 

Corning    Photo-Sensitive   Glass 

An  article  descriptive  of  the  development, 
characteristics  and  applications  of  photo- 
sensitive glass  appears  in  the  July  1948  issue 
of  the  Journal  of  the  Physical  Society  of 
America.  The  author  is  Dr.  S.  D.  Stookey, 
research  chemist  for  Corning  Glass. 

Photo-sensitive  glass  is  described  as  an 
optically  homogeneous  medium  having  the 
properties  of  typical  clear  glass,  yet  capable 
of  incorporating  a  photographic  image  after 
exposure  to  ultraviolet  light  and  to  heat. 
Controlled  colors  of  images  include  red, 
yellow,  blue,  purple  and  amber. 

Applications  are  found  in  the  fields  of 
portrait  and  scenic  photography,  jewelry, 
murals,  windows,  optical  instruments,  instru- 
ment dials,  lantern  slides,  sound  tracks,  and 
lighting  devices. 


Why  Silver  is  'Metallic  Nobility' 

Silver  is  called  a  "noble"  metal  because 
it  is  "incorruptible",  meaning  that  it  resists 
acids,  chemicals  and  corrosion.  That  is  the 
chief  reason  why  silver  has  so  many  and  such 
varied  industrial  uses. 


16 


INTERNATIONAL  PROJECTIONIST 


January  1949 


Flicker  in  Motion  Pictures 

CONTINUING  his  extensive  investigation  into  the  causes  and  correction  of 
flicker  in  motion  picture  projection,  Loren  D.  Grignon  (20th  Century-Fox 
Studios)  makes  a  further  contribution  to  the  literature  on  the  topic  in  a  paper 
in  the  current  SMPE  Journal.*  Exhaustive  tests  carried  out  are  described — 
including  data  as  to  their  nature,  the  equipment  used,  and  the  conditions  under 
which  they  were  made — and  the  Grignon  paper  contains  observations  and  con- 
clusions, excerpts  from  which  are  appended  hereto: 
Before  proceeding  with  a  program  of      trains  with    a  minimum  of  backlash  or 


tests,  a  flicker-free  projector  was  needed 
to  evaluate  the  flicker  samples  visually. 
Flicker  in  projectors  is  caused  by  (a) 
shutter  rate,  (b)  nonuniform  shutter 
velocity,  (c)  arc-supply  ripple,  and  (d) 
arc-burning  characteristics. 

The  effects  of  (a)  are  generally 
known.  Most  projectors  are  supplied 
with  two-bladed  shutters  producing  a 
48-cycle  shutter  rate  which  is  sufficiently 
high,  at  present  illumination  levels,  to 
be  of  secondary  importance. 

Multi-Blade  Shutter  Requisites 

In  studio  review  rooms  a  three-bladed 
shutter  frequently  is  used.  No  studies 
were  made  of  two-  versus  three-bladed 
shutters.  One  point  concerning  shutters 
should,  however,  be  made.  Any  multi- 
bladed  shutter  must  be  symmetrical, 
otherwise  the  24-cycle  frame  rate  is 
reintroduced  and  frame  flicker  becomes 
apparent. 

The  shutter  used  for  all  visual  work 
consisted  of  three  93-degree  blades  and 
three  27-degree  openings.  It  is  currently 
used  in  all  studio  review  rooms  at  20th 
Century-Fox. 

Nonuniform  shutter  velocity  can  re- 
sult from  poor  driving  motor  operation 
or  excessive  mechanical  backlash  be- 
tween driving  point  and  shutter  shaft. 
Analogously,  backlash  can  be  considered 
as  a  complex  nonlinear  compbance 
which  in  concert  with  the  masses  in- 
volved can  be  resonant.  Many  cases  of 
long  gear  trains  with  large  backlash  on 
currently  used  equipment  have  been 
noted  with  attendant  flicker  observable  in 
the  projected  picture. 

In  order  to  evaluate  the  seriousness 
of  the  shutter  nonuniformity,  a  tempor- 
ary filtered  shutter  was  devised  and  ap- 
plied. The  design  was  not  wholly  satis- 
factory because  of  an  insufficiently  low 
cutoff  frequency,  but  it  served  to  demon- 
strate that  the  higher-frequency  flicker 
components  could  be  noticeably  attenu- 
ated. 

Arc-Supply  Ripple  Worst  Offender 

This  part  of  the  work  has  not  pro- 
gressed beyond  this  point.  It  is,  how- 
ever, clear  that  projector  improvements 
either    should    include    shortened    gear 


some  type  of  damped  or  filtered  shutter. 

Arc-supply  ripple  is  the  worst  source 
of  flicker.  Any  60-cycle  component 
greater  than  0.15%  will  cause  a  12-cycle 
flicker  resulting  from  beats  between  the 
60  and  the  48  cycles  of  a  two-bladed  or 
the  72  cycles  of  a  three-bladed  shutter. 
Supplies  operating  from  50-cycle  sources 
do  not  produce  the  same  result  since  the 
beat  frequencies  are  2  and  22  cycles, 
respectively. 

Unfortunately,  it  has  generally  been 
considered  that  three-phase  rectifiers  and 
motor-generator  sets  require  filtering 
only  for  the  theoretical  higher  frequen- 
cies prevalent  and  that  any  60-cycle  com- 


ponents are  low  enough  to  be  neglected. 
This  is  not  true. 

Consider  the  three-phase  rectifier. 
Either  unbalanced  line  voltages  or  dif- 
ferences in  rectifier  element  voltage 
drops  will  introduce  bne-frequency  com- 
ponents and  these  must  be  safeguarded 
against  by  some  filtering  which  is  effec- 
tive at  such  frequencies.  Motor-gener- 
ator sets  can  also  contain  line-frequency 
components  resulting  from  armature 
slots  or  rotational  effects.  Six-phase 
rectifiers  are  superior  in  this  regard  be- 
cause they  tend  to  contain  less  60-cycle  ■ 
components. 

„In  view  of  the  foregoing  remarks,  the 
cure  is  obvious,  but  it  is  surprising  to 
learn  that  single-phase  rectifiers  having 
insufficient  filtering  are  used  for  arc 
supplies. 

Additional  Series  Inductions 

To  eliminate  the  difficulties  from  60- 
cycle   ripple,    all    studio    projectors    em- 
ploying   three-phase    rectifiers    for    arc 
supply    are    being   equipped   with   addi- 
(Continued  on  page  25) 


Effective  First-Aid  in  the  Event  of  Electric  Shock 

THE  fact  that  voltages  employed  in  television  equipment  are  sufficiently  high 
'  to  endanger  human  life  is  stressed  in  a  recent  bulletin  issued  by  RCA  on  its 
new  TP-16A  Tv  film  projection  equipment.  Pointing  out  that  every  reasonable 
precaution  has  been  observed  in  design  to  safeguard  operating  personnel,  RCA 
advises  that  power  be  removed  completely  before  changing  tubes  or  making 
any  internal  adjustments. 

Supplementing  this  warning  are  instructions  anent  first-aid  treatment  in  case 
of  electric  shock.  IP  believes  that  these  instructions  merit  the  widest  possible 
dissemination.   Here  they  are: 


Step-by-Step  Procedure 

1.  Protect  yourself  with  dry  insulat- 
ing material. 

2.  Break  the  circuit  by  opening  the 
power  switch  or  by  pulling  the  victim 
free  of  the  live  conductor.  Don't  touch 
victim  with  your  bare  hands  until  the 
circuit  is  broken. 

3.  Lay  patient  on  stomach,  one 
arm  extended,  the  other  arm  bent  at 
elbow.  Turn  face  outward  resting  on 
hand  or  forearm. 

4.  Remove  false  teeth,  tobacco  or 
gum  from  patient's  mouth. 

5.  Kneel,  straddling  patient's 
thighs  (see  A). 

6.  Place  palms  of  your  hands  on 
patient's  back  with  little  fingers  just 
touching  the  lowest  ribs. 


7.  With  arms  straight,  swing  for- 
ward gradually  bringing  the  weight  of 
your  body  to  bear  upon  the  patient 
(see  B). 

8.  Swing  backward  immediately  to 
relieve  the  pressure  (see  C). 

9.  After  two  seconds,  swing  for- 
ward again.  Repeat  12  to  15  times 
per  minute. 

10.  While  artificial  respiration  is 
continued,  have  someone  else: 

(a)  Loosen  patient's  clothing. 

(b)  Send  for  Doctor. 

(c)  Keep  patient  warm. 

11.  If  patient  stops  breathing,  con- 
tinue artificial  respiration.  Four  hours 
or  more  may  be  required. 

12.  Do  not  give  liquids  until  pa- 
tient is  conscious. 


t  "Further    Flicker    Studies,"    J.    Soc.    of    Mot. 
Eng.  for  December,   1948,   No.  555. 


Pict. 


INTERNATIONAL  PROJECTIONIST 


January  1949 


17 


IN  THE 

SPOTLIGHT 


By 

HARRY 

SHERMAN 


r\  ESPITE  the  moaning  and  groaning 
L^by  certain  segments  of  the  motion 
picture  industry,  it  is  worthy  of  note  that 
several  distributors  have  discontinued  co- 
operative exhibitor  advertising  because 
"intensive  and  extensive  research  has  re- 
vealed that  the  country's  theatres  are 
earning  a  heavy  profit"  and  thus  are  able 
to  assume  the  entire  burden  of  local  ad- 
vertising. While  box-office  income  unde- 
niably is  below  the  lush  take  of,  say, 
1946-47,  overall  attendance  and  income 
figures  still  are  able  to  support  Messrs. 
Distributor  and  Exhibitor  in  the  plush 
style  to  which  they  are  accustomed. 

Inter-industry  moaning  is  regarded  in 
certain  quarters  as  inspired  by  the  desire 
to  effect  slashes  in  employment  rosters 
and  wages;  while  the  quips  by  those 
oracles  outside  the  industry  add  up  to 
typical  know-nothing  comments  by  irre- 
sponsible columnists. 

The  well-informed  know  that  two  major 
factors  are  contributing  to  the  slackened 
production  pace  in  Hollywood:  (1)  the 
heavy  backlog  of  pictures  made  but  not 
yet  released  which  the  producers  wish  to 
amortize  before  embarking  on  new  ven- 
tures, and  (2)  the  growing  number  of 
reissues,  the  character  of  which  the  pa- 
tron frequently  does  not  discover  until 
he  has  gained  admittance  to  the  theatre 
at  regular  box-office  prices. 

Add  to  the  foregoing  the  fact  that  no 
less  than  65  features  will  be  made  abroad 
by  American  interests  within  the  next 
year,  and  we  have  a  prime  cause  for  un- 
employment by  Hollywood  acting  talent 
and  technicians. 

•  IA  President  Walsh  has  been  named 
to  a  five-man  committee  which  will  super- 
vise changes  in  the  by-laws  of  Labor's 
League  for  Political  Education.  Pro- 
posed changes  in  the  by-laws  will  permit 
the  League  to  accept  10-cent  contribu- 
tions from  all  AF  of  L  members  to  fi- 
nance a  14-month  political  education 
drive. 

•  Lester  B.  Isaac,  projection  supervisor 
for  Loew's,  Inc.,  was  appointed  technical 
director  for  the  "gala"  and  ball  that  will 
mark  President  Truman's  inauguration 
January  19-20.  Lester,  one  of  the  ablest 
technicians   in    the   industry,   will   direct 


the  installation  of  lighting  and  sound 
effects. 

•  Local  380,  Oklahoma  City,  Okla.,  will 
celebrate  its  34th  anniversary  the  latter 
part  of  next  month. 

•  The  regular  December  meeting  of  Lo- 
cal 164,  Milwaukee,  Wis.,  was  devoted 
almost  exclusively  to  the  showing  of  two 
very  interesting  and  instructive  motion 
pictures — "The  History  of  the  IA"  and 
National  Carhon  Company's  Technicolor 
feature  "Carbon  Arc  Projection."  Both 
films  were  enthusiastically  received  by 
the  members. 

A  talk  by  C.  E.  Heppberger,  technical 
specialist  for  National  Carbon,  preceded 
the  showing  of  the  carbon  picture;  John 
Lysaght  and  G.  W.  Overall,  field  repre- 
sentatives for  the  company,  were  also 
present.  Ampro  equipment,  furnished  by 
Wisconsin  Sound  Equipment  Co.,  was 
used  for  both  films. 

•  Floyd  Blackman,  president  of  Local 
399,  Bartlesville,  Okla.,  and  1st  vice- 
president  of  the  Oklahoma  Federation  of 
Labor,  attended  the  Federation's  recent 
executive  board  meeting  held  in  Okla- 
homa City. 

e  Recent  out-of-town  visitors  to  the  offi- 
ces of  IP:  Dick  K.  Chastain,  member  of 
Local  322,  Charlotte,  N.  C,  who  spent 
the  holidays  visiting  his  daughter  in  New 
Haven,  Conn.;  Ralph  Grimes,  secretary 
of  Local  224,  Washington,  D.  C;  Walter 
Roberts,  Local  178,  Salisbury,  N.  C,  and 
John  Romansky,  Local  645,  Rockland 
County,  N.  Y.  From  Local  223,  Provi- 
dence, R.  I.,  came  the  Slaters — Harvey, 
Lester,  Herbert  F.,  Jr. — and  Arthur  Jack- 
son. The  Providence  delegation  came  to 
this  city  for  the  express  purpose  of  get- 
ting a  line  on  behind-the-scenes  activi- 
ties at  television  stations.  Arrangements 
were  made  for  them  to  visit  the  Daily 
News  tele  station  WPIX,  and  with  the 
able  assistance  of  the  projectionist  on 
duty,  L.  Menasche,  member  of  Local  306, 
we  think  these  men  gleaned  enough  in- 
formation to  render  a  comprehensive  re- 
port to  their  membership. 

•  We  were  stunned  to  learn  of  the  un- 
timely death  of  our  very  good  friend, 
Harry  F.  Petty,  52,  member  of  Local  163, 
Louisville,  Ky.    He  died  early  last  month 


of  a  heart  attack  while  working  in  the 
projection  room  of  Loew's  Theatre,  where 
he  had  been  employed  for  the  past  20 
years. 

Harry  Petty  had  a  long  and  colorful 
career  as  a  labor  leader  and  was  a  popu- 
lar figure  at  trade  union  meetings  and 
conventions.  At  the  time  of  his  death  he 
was  president  of  the  Kentucky  State 
Federation  of  Labor  and  was  editor  of 
the  Kentucky  Labor  News.  He  was  also 
vice-president  of  the  Louisville  Central 
Labor  Union.  Harry  served  for  many 
years  as  an  officer  of  his  Local,  and  was 
a  delegate  to  a  number  of  IA  conven- 
tions. He  is  survived  by  his  wife  and  a 
brother,  Samuel  Petty. 

•  Ben  Hull,  Local  186,  Springfield, 
Mass.,  associate  director  of  the  State  De- 
partment of  Labor  and  Industries,  and 
vice-president  of  the1  Massachusetts  State 
Federation  of  Labor,  delivered  a  forceful 
and  educational  talk  on  the  results  of  the 
recent  national  election  to  the  delegates 
attending  a  Central  Labor  Union  meet- 
ing early  last  month.  He  characterized 
the  results  as  the  greatest  victory  ever 
won  in  the  history  of  organized  labor, 
and  warned  his  listeners  to  be  on  their 
guard  against  the  enemies  of  labor  who 
would  rob  them  of  their  hard-earned 
benefits  gained  during  the  last  25  years. 

•  T.  Robertson,  vice-president  of  Local 
105,  London,  Canada,  and  projectionist 
at  the  Granada  Theatre  in  St.  Thomas, 
received  high  Masonic  honors  last  month 
when  he  was  elevated  to  the  coveted  office 
of  Worshipful  Master  of  St.  Thomas 
Lodge  No.  44,  AF  &  AM. 

•  Protracted  negotiations  between  Pitts- 
burgh Local  171  and  the  chain  theatres 
in  its  jurisdiction — Warners,  Loew's, 
Harris  and  Shea  Theatres — were  ended 
recently  with  the  signing  of  new  three- 
year  contracts  providing  for  wage  in- 
creases from  7V2  to  12%,  retroactive  to 
September  1,  1948.  IA  representative 
Fitzgerald  assisted  the  Local  in  the  ne- 
gotiations. 

•  One  of  the  highlights  at  the  45th  an- 
niversary party  recently  given  by  Local 
105,  London,  Canada,  was  the  awarding 
of  gold  life  membership  cards  to  charter 
members     Joseph     Moran     and     George 


78 


INTERNATIONAL  PROJECTIONIST 


January  1949 


Cowie.  William  Neuman,  member  of  the 
Local  for  45  years,  was  presented  with 
a  gold  IA  ring. 

•  The  IA  General  Executive  Board  will 
hold  its  mid-winter  meeting  at  the  Roose- 
velt Hotel,  New  Orleans,  La.,  the  week 
beginning   January   31. 

•  J.  Pries,  business  agent  for  Local  225, 
Atlanta,  Ga.,  was  unanimously  re-elected 
to  office  for  his  third  consecutive  term. 
His  popularity  with  the  membership  has 
grown  steadily  the  last  few  years  and  it 
was  further  enhanced  when,  despite  ex- 
isting contracts  which  do  not  expire  until 
1951,  he  was  instrumental  in  gaining  for 
his  membership  cost-of-living  increases 
each  year  for  the  past  three  years.  Jake 
has  long  been  a  strong  advocate  of  keep- 
ing management-labor  relations  on  a 
friendly  and  cooperative  basis,  and  he 
believes  that  all  differences  between  these 
two  groups  can  be  settled  amicably  if 
both  sides  adopt  a  give-and-take  attitude. 

•  Wm.  Reed,  charter  member  of  Local 
310,  Atlantic  City,  N.  J.,  was  recently 
presented  with  a  gold  life-membership 
card  in  the  Local.  Reed  is  now  in  his 
late  80's  and  claims  to  be  the  oldest  pro- 
jectionist in   the  business. 

•  News  of  the  sudden  death  early  this 
month  of  Eugene  Granada,  40,  shocked 
his  many  friends  in  the  Alliance.  He  was 
a  member  of  Local  366,  Westchester  Co., 
N.  Y.,  and  had  been  employed  as  an 
electrician  with  the  Broadway  hit  play 
"A  Street  Car  Named  Desire."  Gene 
was  a  son-in-law  of  Joe  Monaco,  business 
agent  of  Local  366,  and  served  with  the 
Army  Air  Corps  in  the  recent  World 
War.  We  extend  our  deepest  sympathy 
to  his  widow,  Dorothy,  and  to  his  other 
survivors. 

•  George  Tradd,  member  of  Boston  Lo- 
cal 182,  has  opened  his  own  projection 
equipment  repair  shop  at  11  Winchester 
Street,  Boston.  Tradd,  a  skilled  techni- 
cian, was  chief  mechanic  for  many  years 
with  the  Theatre  Service  and  Supply  Co. 
We  join  a  host  of  others  in  wishing  him 
luck  in  his  new  venture. 

•  Local  380,  Oklahoma  City,  Okla., 
placed  one  of  its  members  with  the  Okla- 
homa Theatre  Supply  Co.  under  the 
terms  of  a  new  contract  which  calls  for 
a  five-day,  40-hour  week  at  $2.25  per 
hour,  plus  vacations  with  pay. 

•  We  were  happy  to  learn  that  A.  S. 
Johnstone,  New  Orleans  Local  293  and 
an  IA  representative,  has  completely 
recovered  from  a  threatened  attack  of 
pneumonia.  Al  was  stricken  while  at- 
tending a  business  conference  in  Char- 
lotte, N.  C,  and  was  confined  to  his  hotel 
room  for  several  days  until  Mrs.  John- 
stone came  up  from  New  Orleans  to  take 
him  home. 


Spotlighting   1948 

•  Floyd  Billingsley  and  Tony  Noriega, 
San  Francisco  Local  162,  appointed  to 
important  State  posts  by  Governor  War- 
ren of  California  .  .  .  Ralph  Grimes, 
Local  224,  Washington,  D..  C,  named  a 
member  of  the  District's  Motion  Picture 
Operators'  Examining  Board  .  .  .  Los 
Angeles  Local  150  settled  long-standing 
wage  negotiations  with  major  theatre 
circuits.  Agreement  provided  for  20c 
per  hour  increase,  retroactive  to  July  1, 
1947  .  .  .  Allen  G.  Smith  succeeded  James 
Frank,  Jr.  as  New  York  City  branch  man- 
ager for  National  Theatre  Supply  Co. 
.  .  .  Charlie  Dentelbeck,  projection  chief 
for  Canadian  Famous  Players,  played 
the  good  samaritan  to  ailing  projection- 
ists .  .  .  San  Antonio  Local  407  pre- 
sented Fred  Raoul,  IA  general  secretary- 
treasurer  with  gold  membership  card  .  .  . 
Abe  Zumar  and  Bill  Hartnett,  secretary 
and  business  manager,  respectively,  of 
Local  257,  Ottawa,  Canada,  reelected  to 
office  for  their  23rd  consecutive  term  .  .  . 
E.  P.  Lehnhoff,  Local  548,  Paris,  Texas, 
formulated  a  plan  to  keep  his  members 
abreast  of  technical  developments  in  the 
industry  .  .  .  Economy  drive  instituted 
by  Hollywood  producers.  Salaries  of  top 
executives  in  several  of  the  major  com- 
panies were  substantially  increased, 
while  employes  in  low-income  brackets 
were  hard  hit  by  wholesale  layoffs. 

Hotly  contested  election  in  New  York 
City  Local  306.  Ernie  Lang  nosed  out 
Frank  Inciardi  for  the  post  of  recording- 
secretary  by  only  one  vote  .  .  .  Chicago 
Local  110  signed  contract  with  tele  sta- 
tion WGN.  The  only  other  tele  station 
in  Chicago,  WBKB,  also  under  contract 
to  the  Local,  thus  making  that  city  100% 
IA  .  .  .  Bert  Sanford,  theatrical  sales  man- 
ager for  Altec,  appointed  to  motion  pic- 

EAGLE-EYED   NIMRODS  OF   LOCAL   143 


The  1948  safari  of  an  annual  Missouri  River 
shoot  again  found  together  Wm.  Briley,  Wm. 
Routszong  and  Adolph  Harbstreet,  all  members 
of  Local  143.  The  boys  got  in  18  days  shooting 
during  the  recent  27-day  season. 


ture  committee  for  1948  Appeal  of  the 
New  York  Catholic  Charities  .  .  .  Inter- 
national Projector  Corp.  played  host  to 
25-30  Club  members  at  its  new  plant  in 
Bloomfield,  N.  J.  .  .  .  Boston  Local  182 
purchased  three-story  building  to  house 
union  headquarters  .  .  .  Members  of 
Pittsburgh  Local  171  agreed  to  donate 
services  to  bed-ridden  veterans  at  Aspin- 
wall  Hospital,  in  the  showing  of  motion 
pictures  twice  weekly  .  .  .  Brooklyn  Local 
4  celebrated  its  60th  anniversary  .  .  . 
The  death  of  Thad  Barrows,  Boston  Lo- 
cal 182,  shocked  his  many  friends 
throughout  the  Alliance  .  .  .  Dallas  Local 
249  presented  gold  membership  cards  to 
C.  E.  (Red)  Rupard,  Henry  Sorenson, 
and  Johnny  Hardin  .  .  .  Tom  Loy,  pub- 
lic relations  counsel  for  the  IA,  became 
the  father  of  a  seven-pound  boy  .  .  . 
George  Thrift,  Vancouver  Local  348,  took 
his  family  to  visit  his  birthplace  in 
England — his  first  trip  back  in  25  years 
.  .  .  Mike  Berkowitz  and  Cecil  Wood,  Sr., 
New  York  Local  306,  celebrated  their 
75th  birthdays  .  .  .  Earl  Tuttle,  Local 
396,  Binghamton,  N.  Y.,  elected  vice- 
president  of  AF  of  L's  Union  Label 
Dept.  .  .  .  Sam  Kaplan,  New  York  Local 
306,  died. 

Gene  Atkinson,  Chicago  Local  110, 
obtained  sweeping  welfare  benefits  for 
his  members  in  unprecedented  5-year 
security  and  pension  pact  with  exhibitors 
.  .  .  Local  414,  Wichita,  Kans.,  signed  up 
the  Fox  Theatres  at  a  15%  wage  in- 
crease, plus  timeand-a-half  for  overtime 
and  two  weeks  vacation  with  pay  .  .  . 
Dick  Walsh  and  the  entire  official  family 
unanimously  reelected  to  office  at  the 
39th  biennial  IA  convention  .  .  .  Tom 
O'Brien,  general  secretary  '  of  NATKE, 
guest  at  the  Cleveland  convention  .  .  . 
Documentary  film,  "The  History  of  the 
IA"  shown  to  the  delegates  at  Cleveland 
.  .  .  Bill  Canavan,  former  International 
president,  observed  his  60th  birthday  .  .  . 
National  Carbon  Co.  took  the  wraps  off 
its  Technicolor  film,  "Carbon  Arc  Pro- 
jection" at  a  special  showing  in  New 
York  .  .  .  Walter  J.  Kunz,  Local  279, 
Houston,  Texas,  died  shortly  after  his 
return  from  Cleveland  .  .  .  Los  Angeles 
Local  150  scored  a  victory  over  the  Board 
of  Building  and  Safety  in  its  fight  to 
have  three  of  its  members  reinstated  as 
examiners  for  the  city  of  L.  A.  .  .  . 
Eastman  Kodak  Co.  splicing  chart  dis- 
tributed free  of  charge  to  IP  readers 
.  .  .  Dick  Walsh  presented  with  gold 
card  at  35th  anniversary  party  of  New 
York  Local  306. 

Joe  Cifre,  Boston  Local  182  and  Chief 
Barker  for  Variety  Club  Tent  No.  23, 
was  cited  for  his  splendid  efforts  in  help- 
ing to  raise  more  than  a  quarter  of  a 
million  dollars  for  the  Children's  Cancer 
Research  Foundation  .  .  .  IATSE  and 
IBEW   reached    an    agreement    on    tele- 

(Continued  on  page  23  I 


INTERNATIONAL  PROJECTIONIST 


January  1949 


19 


Lumens  and  Electrons 

By  W.  W.  LOZIER  and  F.  T.  BOWDITCH 
National  Carbon  Company  Laboratories 


r\EFINITIONS  in  the  field  of  light  (the  foot-candle, 
■^  lumen,  candlepower,  etc.)  are  based  upon  a  rate  of 
flow  of  luminous  energy,  the  lumen  being  analogous  to 
the  ampere  in  this  respect.  Just  as  the  ampere  specifies 
a  rate  of  flow  of  current  in  an  electrical  circuit,  so  does 
the  lumen  specify  a  rate  of  flow  of  luminous  energy 
through  space. 

Both  of  these  units  are  fundamentally  concerned  with 
reactions  involving  single  electrons,  and,  except  for  the 
astronomic  size  of  the  number  required  to  specify  quanti- 
ties of  practical  interest,  each  phenomenon  might  be  ex- 
pressed in  terms  of  the  appropriate  single  electron  be- 
havior. A  current  of  one  ampere  would  thus  correspond 
to  a  flow  of  electrons  in  an  electrical  circuit  at  the  rate 
of  6.28  x  1018,  or 

6,280,000,000,000,000,000  electrons  per  second. 
The   cumbersome   nature   of   such   a   specification   is    ap- 
parent, but  the  picture  thus  created  is  nevertheless  of  value 
in  visualizing  what  is  really  going  on  when  current  flows. 

Similarly,  light  is  generated  one  photon  (one  quantum) 
at  a  time,  as  a  portion  of  the  energy  possessed  by  an 
electron  is  converted  to  radiant  energy  of  a  particular 
wave-length.  The  number  of  these  light  pulses  per  second 
associated  with  a  light  source  familiar  to  a  projectionist 
— say,  a  70-ampere  arc  with  Suprex*  carbons — is  a  figure 
which,  like  that  associated  with  the  ampere,  might  give 
an  interesting  picture  of  the  atomic  reaction  rates  re- 
sponsible. The  derivation  of  such  a  figure,  however,  is 
quite  complicated  and  requires  consideration  of  the  atomic 
processes  from  which  the  light  arises. 

The  electrons,  whose  energy  changes  give  rise  to  pho- 
tons, revolve  in  orbits  around  the  nuclei  of  the  atoms  of 
which  they  are  a  part.  There  are  many  orbits  associated 
with  a  particular  nucleus,  each  characterized  by  its  own 
energy   value.    When   the   atom   is   in   a   stable   state,   its 


*  The  term  "Suprex"  is  a  trade-mark  of  National   Carbon  Company,  Inc. 


3xl0° 

k 
k 

| 

\ 
\ 

hlom 

VIOLET  1    BLUE 

VELLOIV-s 

1  *•  1  < 
GREEK              \ 

f  ORANGE 
'  1 

RED 

4000  SOOO  6000  7000 

Wavelength  —  angst/so/vs 

FIG.  2.    Graphical  exposition  of  the  number  of  photons  per  second  to 
produce   one   watt   of   radiation   of  various  wave-lengths. 


FIG.  1.  Showing 
electron  orbits 
and  energy  levels 
around  positively- 
charged  nucleus. 
Electron  transi- 
tions from  outer 
to  inner  orbits 
cause  difference 
in  energy  to  be 
emitted  as  radia- 
tion. 


electrons  are  all  revolving  in  orbits  of  relatively  low  energy. 

When  the  atom  becomes  "excited,"  as  by  heating  or 
as  the  result  of  bombardment,  one  (or  more)  of  its  elec- 
trons may  be  given  extra  energy  so  that  it  now  revolves 
in  an  orbit  of  higher  energy,  in  which  situation  it  is  un- 
stable and  will  often  revert  to  a  lower  energy  level. 

As  long  as  an  electron  remains  in  one  orbit  (or  at  one 
energy  level)  no  light  is  radiated;  but  when  an  electron 
falls  into  a  lower,  more  stable  energy  level,  closer  to  the 
nucleus,  the  difference  in  energy  between  the  two  orbits 
is  emitted  as  a  photon  of  radiation.  This  is  diagrammed 
in  Fig.  1  for  the  simplest  atom — namely,  the  one-electron 
hydrogen  atom.  Here  the  orbits  have  been  shown  as  cir- 
cular. Actually,  they  are  often  of  more  complex  form, 
but  they  are  still  characterized  by  the  fact  that  there  is  a 
single  energy  value  associated  with  each  orbit. 

The  amount  of  energy  possessed  by  a  photon  determines 
the  frequency  of  the  radiation,  according  to  the  following 
well-known  quantum  relation  so  basic  to  all  modern 
physics : 

Energy  of  Photon  =  Planck's  Constant  X  Frequency 
of  Radiation 

The  frequency  determines  the  wave-length  of  the  radia- 
tion. If  the  wave-length  falls  in  the  range  4000  to  7000 
Angstroms,  then  the  radiation  is  visible.  Otherwise,  it  is 
either  in  the  infra-red  region  (if  of  longer  wave-length) 
or  in  the  ultra-violet  (if  of  shorter  wave-length) . 

A  complex  atom  with  more  than  one  electron  will  be 
characterized  by  a  multiplicity  of  possible  energy  levels 
and  transitions  between  them,  so  that  the  generation  of 
photons  of  many  different  energies  (and  wave-lengths) 
becomes  possible. 

Determination  of  Color  Characteristics 

For  example,  the  cerium  atoms  in  the  rare  earths  em- 
ployed in  projector  carbons  contain  no  less  than  58  elec- 
trons. Under  the  tremendous  electron  bombardment 
present  in  the  high-intensity  carbon  arc,  there  results  such 
a  large  number  of  "excitations"  to  the  many  higher  levels, 
followed  by  the  emission  of  these  added  energies  as  pulses 
of  radiation,  that  practically  all  wave-lengths  throughout 
the  visible  region  of  the  spectrum  are  present  in  the  light 
which  is  generated.  This  results  in  the  snow-white  color 
so.  characteristic  of  this  arc. 

The  quantitative  expression  derived  from  the  above 
quantum  equation  and  shown  in  Fig.  2  will  enable  us  to 
proceed  with  the  task  of  computing  the  number  of  photons 


20 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


hs.o 

k  o 

Iq  k 
£   0 

*  o  z.o 
0  iv 

I* 

SOOO  6000 

WAVELENGTH    —    ANGSTROMS 


FIG.  3.    Spectral  energy  distribution  of  radiation  through  aperture  from 
70-amp  arc  with  8-  7  mm  Suprex  carbons — no  shutter  or   filters. 

per  second  associated  with  the  70-ampere  arc  with  Suprex 
carbons.  This  graph  shows  the  number  of  photons  per 
second  required  to  produce  a  radiant  intensity  of  1  watt 
at  each  wave-length  over  the  visible  spectrum.  This  ranges 
from  approximately  2  billion  billion  photons  per  second 
at  the  blue  end  to  approximately  3.5  billion  billion  at  the 
red  end  of  the  band  of  visible  radiation. 

The  straight-line  relation  shown  in  Fig.  2  can  be  ex- 
tended at  both  ends  to .  apply  to  radiation  in  both  the 
ultra-violet  and  infra-red  regions  of  the  spectrum. 

It  is  apparent,  therefore,  that  the  number  of  photons 
per  second  radiated  from  any  particular  light  source  de- 
pends upon  how  the  intensity  of  that  source  varies  with 
wave-length,  that  is,  the  watts  associated  with  each  wave- 
length radiated.  Such  information  is  given  by  a  spectral 
energy  distribution  curve  and  can  be  combined  with 
Fig.  2  to  determine  the  number  of  photons  per  second  in 
the  visible  range  for  the  source  specified.  Such  a  calcula- 
tion for  the  familiar  70-ampere  projection  arc  with 
Suprex  carbons,  based  on  the  spectral  energy  distribu- 
tion curve  shown  in  Fig.  3,  results  in  a  figure  of  approxi- 
mately 

200,000,000,000,000,000,000  or 
200  billion  billion  photons  per  second 
passing  through  the  film  aperture,  with  no  shutter  or  filters 
in  the  light  beam.  When  a  count  is  made  of  the  radia- 
tion of  all  wave-lengths,  whether  visible  or  not,  it  is 
found  that  approximately  900  billion  billion  individual 
corpuscles  of  radiation  pass  through  the  aperture  each 
second. 

Light  of  Varying  Wave-Lengths 

In  order  to  correlate  the  rate  of  emission  of  photons 
with  more  familiar  photometric  quantities  such  as  lumens 
and  foot-candles,  it  is  necessary  to  consider  the  properties 

TABLE  A.  Number  of  Photons  per  Second  per  Lumen.t 


70-Ampere  Suprex  Carbons 
30-Ampere  Low-Intensity  Carbons 


50  Million  Billion 
150  Million  Billion 


J     soo 

H.       *CO 


VI OLE!  BLUE 

GHEEN    1  f  |  +  1         RED 

YELLOW  J     ^ORANGE 

4000                   SOOO  6000  70OO 

WAVE  — LENGTH />NGSTR OMS 

FIG.   4.    Visibility  curve:  showing   the   number  of   lumens   per   watt  of 
radiation  of  various  wavelengths. 

of  the  human  eye,  since  this  reacts  differently  to  photons 
of  each  wave-length.  This  relationship  is  described  by 
the  familiar  visibility  curve  shown  in  Fig.  4.  According 
to  this  relation,  one  watt  of  green  light  of  wave-length 
5550  A  produces  an  illumination  of  650  lumens,  while 
both  shorter  and  longer  wave-lengths  are  much  less 
effective,  producing  zero  illumination  at  the  limits  of  the 
visible  region. 

The  lumen  unit  is  a  measure  of  the  visibility  sensation 
associated  with  a  light  source,  so  that  sources  of  equal 
lumen  output  produce  equal  visual  sensation,  regardless 
of  color  differences.  The  watt  unit  as  applied  to  radia- 
tion is  a  measure  of  its  energy  content,  and  sources  of 
radiation  possessing  the  same  wattage  content  will,  when 
absorbed,  produce  the  same  heating  effect  regardless  of 
color. 

The  visibility  curve,  when  combined  with  the  spectral 
energy  distribution  curve  for  any  light  source,  permits 
the  determination  of  the  lumens  associated  with  the  radia- 
tion. When  this  calculation  is  carried  through  for  the 
70-ampere  arc  with  Suprex  carbons,  it  is  found  that  the 
total  illumination  falling  on  the  aperture  without  shutter 
or  filters  is  approximately  17,000  lumens.** 

Combination  of  this  illumination  with  the  previously 
determined  photon  frequency  results  in  a  value  for  the 
70-ampere  Suprex  radiation  of  approximately 

50  million  billion  photons  per  second  per  lumen 

for  all  wave-lengths  falling  on  the  film  aperture.  The 
result  of  a  similar  calculation  for  the  30-ampere,  low- 
intensity  carbon  arc  is  also  given  in  Table  A. 

Difference  Between  H-l  and  L-l  Arcs 

Since  one  electron  transition  in  the  arc  is  associated 
with  each  photon  emitted,  these  figures  picture  the  terrific 
electron  activity  that  the  projectionist  has  under  his  con- 
trol and  brings  into  action  when  he  "strikes  the  arc"  and 
opens  the  dowser.  The  threefold  greater  number  of 
photons,  and  hence  more  intense  electron  activity,  requried. 
per  lumen  of  illumination  produced  by  the  low-intensity 
carbon  arc  results  from  the  fact  that  more  of  its  energy 


f  Radiation  through  film  aperture. 
INTERNATIONAL  PROJECTIONIST     •     January  1949 


**  Corresponding  values  of  screen  lumens  are  shown  under  the  heading  of 
"Maximum  Light"  in  the  last  column  of  Table  VIII,  page  63,  of  the  National  Carbon 
Co.  Handbook  on  Projector  Carbons,  4th  Edition. 


21 


is  in  the  infra-red  region  than  is  the  case  with  the  high- 
intensity  carbon  arc.  This  infra-red  radiation  represents 
photons  and  electron  transitions  which  produce  no  visible 
radiation. 

These  huge  figures  and  the  methods  by  which  they  were 
derived  are  obviously  too  awkward  for  everyday  use. 
Having  thus  served  their  purpose,  they,  along  with  the 
electron  rate  corresponding  to   one  ampere,   can  best  be 


laid  aside.  For  engineering  use,  the  lumen  and  the  ampere 
continue  to  be  preferred,  because  they  are  numerically 
less  cumbersome,  and  meters  are  available  which  permit 
their  determination  directly. 

A  visualization  of  fundamental  processes  and  involved 
calculations  is  not  essential  to  the  effective  engineering 
use  of  such  data.  A  glance  at  the  basic  picture  once  in  a 
while  is  sufficient. 


New  RCA  Seat-Phone  System 

A  new  line  of  theatre  seat-phone  equip- 
ment for  the  hard-of-hearing  is  now  available 
from  RCA.  The  equipment  (PG-130C)  fea- 
tures a  tamper-proof  single  jack  box  having 
no  exposed  screws  or  nuts  for  mounting  on 
the  rear  section  of  a  chair  arm  or  on  the 
metal  partition  just  under  the  arm. 

To  simplify  installation,  a  six-foot  length 


of  armored  cable  is  clamped  into  each  jack 
box,  which  consists  of  two  cast  aluminum 
sections  joined  by  an  Allen  set  screw  inside 
the  housing.  An  Allen  wrench,  supplied,  is 
inserted  through  the  jack  for  removing  the 
cover  or  for  locking  it.  Both  wood  screws 
and  self-tapping  screws  are  included  in  the 
kit  for  each  box  so  that  the  base  may  be 
mounted  on  any  type  chair.  A  protective 
resistor  within  the  box  circuit  prevents  inter- 


FOR  BEAUTIFUL 
ROCK  STEADY  PROJECTION 


FOR  LIFELIKE  SOUND 

GET 

MOTIOGRAPH 

and  have   the  finest 
FOR   DRIVE-INS 

a  complete  line  of  proven  central  loudspeaker,  post- 
type  and  in-car  speaker  equipment. 

FOR  LONG,  TROUBLE-FREE  SERVICE 


Motiograph      has     equipment     especially 
designed   for   theatres   of   all   sizes. 


Write  for  literature   today   or  see 
your  Motiograph  dealer. 


4431   W.  LAKE  ST.,      CHICAGO    24,    ILL. 


ference  with  other  units  in  case  of  a  "short" 
in  any  phone  in  use. 

Protective  Features,  Simple  Installation  Setup 

The  equipment  includes  a  high-quality 
bridging  amplifier  mounted  in  the  projection 
room  and  connected  into  the  theatre  sound 
system.  Direct  operation  from  an  a-c  line 
and  a  separate  volume  control  isolate  the 
equipment  so  that  its  use  has  no  effect  upon 
the  theatre  sound  system. 

Installation  is  simple:  conduit  is  run  from 
the  projection  room  into  the  auditorium  floor 
to  the  selected  seats.  Condulets  connect  the 
armored  cable  from  the  jack  box  to  the  audio 
lines  from  the  bridging  amplifier  in  the  pro- 
jection room.  The  equipment  is  available  in 
types  for  either  air  or  bone  conduction,  with 
headband  or  lorgnette  handle. 


2  New  18-Inch  Film  Magazines 
by  Wenzel  Augment  Line 

Two  new  18-inch  projector  magazines — 
the  De  Luxe  and  the  Standard — have  been 
announced  by  Wenzel  Projector  Co.,  Chicago. 
These  new  magazines  are  %  inch  deeper  on 
the  rear  wall  and  provide  practically  9/16 
inch  clearance  between  the  reel  and  the  wall. 
The  shafts  on  both  upper  and  lower  maga- 
zines are  %  inch  diameter  through  the 
length  of  the  bearing  surface. 

On  the  upper  magazine,  the  part  of  the 
shaft  which  carries  the  tension  adjustments 
will  retain  the  present  %  inch  diameter, 
since  there  are  some  reel-end  alarms  made 
to  attach  to  this  diameter  shaft. 

Oilite  Bearings  Reduce  Maintenance 

The  upper  magazine  shaft  runs  in  two 
flanged  oilite  bearings  pressed  in  from  each 
side  of  the  magazine  bracket,  leaving  a  slight 
gap  between  the  two  inner  ends  of  the  bear- 
ings to  serve  as  an  oil  reservoir.  A  dash  of 
oil  every  few  weeks  is  all  the  lubrication 
necessary. 

Both  ends  of  the  bracket  are  recessed  so 

Wenzel   de-luxe   18-inch   magazine. 


22 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


the  flange  faces  of  the  bearings,  the  steel 
collar  on  the  reel  shaft  inside  the  magazine 
and  the  steel  collar  used  in  the  tension 
spring  are  steel  against  oilite,  thus  barring 
any  chance  of  uneven  wear  or  freezing  at 
these  two  points.  The  lower  magazine  shaft 
runs  in  a  hardened  and  ground  steel  bear- 
ing. The  bearing  surface  of  the  upper  maga- 
zine is  2  7/16  inches  long,  that  of  the  lower 
magazine  4  1/16  inches. 

New  aluminum  brackets  have  been  de- 
signed for  these  magazines,  the  extruded 
edges  being  highlighted.  A  new  design  door- 
opener  has  also  been  adopted,  and  the  sash 
of  the  film  window  glass  is  nickel-polished. 
A    new    type    positive-acting    spring    tension 

Record  Kodak  Wage  Dividend 

A  record-breaking  wage  dividend  of  an 
estimated  $13  million  for  about  51,500  em- 
ployees in  the  western  hemisphere  has  been 
voted  by  Eastman  Kodak  Co.  The  wage  divi- 
dend, largest  total  amount  in  the  37-year 
history  of  the  plan  at  Kodak,  will  be  paid 
next  March.  Eligible  employees  will  receive 
$22.50  for  each  $1,€00  earned  during  1944 
through  1948. 

Last  year  the  wage  dividend  totaled  ap- 
proximately $11,600,000  for  49,300  employees. 


A.  J.  SEXTON,  JR.— General  Man- 
ager, Sexton  Theatre  Company, 
Ashland,  Kentucky — says: 

"An  RCA  Service  contract 
has  proved  to  me  the  best  in- 
vestment any  theatre  owner 
could  make  for  the  finest  en- 
gineering and  mechanical 
upkeep  of  booth  equipment. 
It  is  essential  in  any  theatre." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


brake  drag  has  been  designed  for  both  upper 
and  lower  magazines. 

The  present  less  expensive  18-inch  upper 
and  lower  magazines  still  will  be  available. 
The  present  18-inch  magazines  will  be  known 
as  Pro-21  and  Pro-22;  the  new  magazines 
will  be  known  as  Pro-31  and  Pro-32.  Com- 
plete details  are  available  from  Wenzel  Pro- 
jector Co.,  2505  S.  State  St.,  Chicago  16. 


IN  THE  SPOTLIGHT 

(Continued  from  page  19) 
vision  jurisdiction  in  New  York  City  .  .  . 
Roy  Brewer,  International  representa- 
tive, reelected  president  of  the  Holly- 
wood Film  Council  .  .  .  IA  documentary 
film  warmly  received  at  Local  Union 
showings  throughout  the  Alliance  .  .  . 
Bert  Ryde,  Buffalo  Local  233,  unanim- 
ously reelected  business  agent  of  the 
Local  for  an  additional  five-year  term 
.  .  .  Detroit  Local  199  negotiated  new 
two-year  contracts  calling  for  wage  in- 
creases .  .  .  Roy  W.  Wier,  Minneapolis 
Local  13,  elected  to  Congress  on  the 
Farmer-Labor  ticket  .  .  .  Two-year  con-, 
tracts  concluded  between  the  IA  and  the 
Altec  and  RCA  service  companies  give 
sound  service  engineers  a  weekly  pay 
raise  of  $10.40,  plus  increased  automo- 
bile allowance  .  .  .  The  death  of  Harry 
Petty,  Louisville  Local  163,  stunned  his 
many  friends  .  .  .  Local  489,  Kansas 
City,  Kans.,  won  court  case  instituted  by 
apprentice  member  .  .  .  Bill  Covert, 
business  representative  for  Toronto  Lo- 
cal 173,  reelected  for  another  five  years 
.  .  .  Local  22,  Washington,  D.  C.  defeated 
charge  of  feather-bedding  .  .  .  New  York 
Local  306  organized  a  16-mm  department 
under  the  direction  of  Charlie  Kielhurn, 
executive  board  member  ...  St.  Louis 
Local  143  celebrated  its  40th  anniver- 
sary .  .  .  New  TMA  (Theatrical  Mutual 
Association)  lodges  formed  throughout 
country;  plans  made  for  1949  national 
convention  in  N.  Y.  City. 

One  of  the  most  encouraging  aspects 
of  the  past  year's  happenings  was  the 
resumption  of  the  close  relationship 
which  existed  between  equipment  manu- 
facturers and  projectionists  in  pre-war 
years.  The  numerous  lectures  and  dem- 
onstrations sponsored  by  manufacturers 


Manufactured  by 

HEYER-SHULTZ,  Inc. 

MONTCLAIR,  N.  J. 


ALL   METAL 

GUARANTEED  5  YEARS 


Distributed  Exclusively  by 


AMERIPOL 

GASKETS 

unaffected  by 

heat  or  oil 


INTEGRA! 
ANODIZED 

FINISH 

can't  flake  or 

peel  oil 

ONE-PIECE 

MOUNT 

no  joint  to  leak 

DURABLE 
ANTI- 
REFLECTION 

COATINGS 
need  no  extra 


,  Each  Snaplite  lens  is  distinguished  by  its 
sleek  black  aluminum  mounting.  The  black 
anodized  finish  is  an  integral  part  of  the 
aluminum— can't-  chip,    flake,    or    peel    off. 


^ROUBLE-FREE  performance  is  as- 
sured  by  the  hermetically  sealed  con- 
struction of  Snaplite  and  Super-Snaplite 
lenses.  They  never  need  to  be  taken 
apart  for  cleaning — no  dust  or  oil  can 
enter!  And  their  anodized  finishes  can't 
flake  off! 

For  brighter  .  .  .  sharper  .  .  .  clearer 
pictures,  use  f/2.0  Snaplites  or  f/1.9 
Super-Snaplites  in  your  projectors!  Full 
details  of  all  Snaplite  lenses  are  given 
in  Bulletin  204,  available  from  your 
local  supply  dealer. 


The  fastest  lens  made 
— the  f/1.9  six-element 
anastigmat  Super- 
Snaplite. 


KOLLA\0 

»  Franklin  Avtmn 
treoUyn  11,  N«w  Ye* 


• 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


COKPOKATIOI 


23 


CHAS.  GREIME  — General  Man- 
ager of  six  Greime  and  Fasken 
Theatres  in  Wenatchee,  Omak  and 
Holden,  Washington — says : 

"We  have  used  RCA  Service 
in  our  various  theatres  for 
the  past  18  years  and  con- 
sider this  service  one  of  our 
greatest  assets." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


Your  Best  Buy  .  .  . 

U.  S.  SAVINGS  BONDS 


for  projectionist  groups,  involving  no 
little  effort  and  expense,  points  to  an 
abandonment  of  the  aloof  attitude  dis- 
played by  manufacturers  during  the  war 
years.  It  is  all  to  the  good  and  will  help 
both  manufacturers  and  the  craft  by  im- 
proving equipment  and  technique. 

IA     ELECTIONS 

LOCAL  105,  LONDON,  CANADA 

J.  E.  Saunders,  pres.;  T.  Robertson,  vice- 
pres.;  C.  Mills,  sec.-treas.;  W.  Hewitt,  Tec- 
sec;  F.  Hewitt,  bus.  agent,  stagehands; 
S.  Bradford,  bus.  agent,  projectionists;  H. 
Allaster,  R.  Courtney,  W.  Hewitt,  trustees; 
F.  Cripps,  W.  Shaw,  auditors;  C.  Mills, 
W.  Hewitt,  exec,  board;  S.  Bradford,  C. 
Mills,  S.  Shaw,  exam,  board;  W.  O'Rourke, 
sgt.-at-arms. 

LOCAL  150,  LOS  ANGELES,  CALIF. 

Earl  Hamilton,  pres.;  Mort  Sands,  vice- 
pres.;  Charles  Vencill,  sec.-treas.;  Magnus 
Nielsen,  bus.  rep.;  Clay  Blanchett,  Frank 
McBryde,  C.  C.  Piper,  Hugh  Smith,  Ken- 
neth Thompson,  Sr.,  exec,  board;  Dale  Gil- 
lum,  H.  J.  Kearney,  and  Clem  Marchand, 
trustees. 

LOCAL  159,  PORTLAND,  ORE. 

L.  R.  Smith,  pres.;  G.  G.  Speck,  vice- 
pres.;  E.  M.  Hazelwood,  rec-sec;  L.  M. 
Davis,  fin.-sec;  Z.  A.  Sax,  bus.  rep.;  L.  R. 


Smith,  E.  M.  Hazelwood,  A.  S.  Phillips, 
C.  W.  Christenson,  Z.  A.  Sax,  exec,  board; 
C.  W.  Christenson,  sgt.-at-arms. 

LOCAL  162,  SAN  FRANCISCO,  CALIF. 

Anthony  L.  Noriega,  pres.;  0.  G.  Roush, 
vice-pres.;  Thomas  J.  Kearney,  sec.-treas.; 
F.  M.  Billingsley,  bus.  rep.;  R.  M.  Wilson, 
H.  Erickson,  R.  M.  Combs,  Jack  Forde,  Jr., 
exec,  board;  Antone  J.  Salemi,  sgt.-at-arms. 

LOCAL  173,  TORONTO,  CANADA 

James  Sturgess,  pres.;  Harry  Jarmain, 
vice-pres.;  Geo.  H.  Jones,  sec.-treas.;  Pat 
Travers,  rec-sec;  Wm.  P.  Covert,  bus.  mgr.; 
Gus  Demery,  Reg.  Jenkins,  Andy  Pura,  W.  E. 
Shields,  exec,  board;  D.  Cameron,  J.  Stringer, 
E.  Whyatt,  trustees;  G.  Robinson,  tyler; 
E.  Nemers,  sgt.-at-arms. 

LOCAL  175,  TACOMA,  WASH. 

0.  J.  Carlson,  pres.;  J.  Shepherd,  sec," 
C.  J.  Kaleel,  treas.;  Howard  Nix,  bus.  rep.; 
A.  E.  Bradshaw,  James  Burke,  Frank  Carlson, 
Ben  Yost,  and  Orin  M.  Jacobson,  exec,  board. 

LOCAL   181,   BALTIMORE,  MD. 

Sam  Isaacson,  pres.;  Wm.  Lang,  1st  vice- 
pres.;  Geo.  Matthews,  2nd  vice-pres.;  Otto 
Niquet,  3rd  vice-pres.;  Wilbur  George,  rec- 
sec;  T.  P.  Finn,  Sr.,  fin.-sec;  Carroll  Bayne, 
bus.  rep.;  Chas.  Grauling,  Walter  Fringer, 
and  Louis  Sieber,  trustees. 

LOCAL  224,  WASHINGTON,  D.  C. 

Wm.  M.  Sheehan,  pres.;  Tom  Reed,  1st 
vice-pres.;  C.  Franks,  2nd  vice-pres.;  T.  D. 
Bittenbender,  3rd  vice-pres.;  M.  D.  Bitten- 
bender,  4-th  vice-pres.;  R.  L.  Grimes,  rec- 
sec;  T.  L.  Hopkins,  fin.-sec;  C.  C.  Fisher, 
bus.  rep.;  DeForest  L.  Ormes,  treas.;  H.  C. 
Connelly,  trustee;  R.  M.  Wise,  guide;  John 
R.  Levy,  guardian. 

LOCAL  225,  ATLANTA,  GA. 

Al  Kemp,  pres.;  W.  P.  Foster,  vice-pres.; 
Bruce  Self,  rec-sec;  M.  Morris,  fin.-sec; 
Jacob  Pries,  bus.  rep. 

LOCAL  233,  BUFFALO,  N.  Y. 

John  J.  Walsh,  Sr.,  pres.;  Michael  Os- 
trowsky,  vice-pres.;  Owen  J.  Kavanagh,  rec 
corr.-sec;  Albert  F.  Ryde,  bus.  rep.  &  fin. 
sec;  Elmer  C.  Winegar,  treas.;  Arthur  G 
Ehrlich,  Kenneth  J.  Kavanagh,  Edwin  J 
Weikert,    trustees;    Walter    Schwend,    Ber 

Novel  'Wiring'  With  Silver  Ink 

Engineers  have  solved  the  problem  of 
making  a  new-type  hearing  aid  as  compact 
as  a  lady's  cigarette  case  by  "wiring  it  with 
silver  ink."  Silver  is  the  best  metallic  con- 
ductor of  electricity,  however  minute  the  por- 
tions. Hence  it  has  been  found  possible  to 
"draw"  the  intricate  and  minute  wiring  sys- 
tem of  the  hearing  device  on  a  thin  "instru- 
ment board"  of  ceramic  material  about  as 
big  as  the  top  of  a  box  of  safety  matches. 

Application  of  heat  to  the  silver  ink  bonds 
it  to  the  board,  and  at  just-right  spots  re- 
sistors, condensers  and  tubes  fit  into  place. 
Midget  batteries  and  microphone  complete 
the  compact  assembly.  "Silver  ink"  is  said 
to  replace  173  tiny  items  that  are  necessary 
in  the  standard  wiring  system  of  a  hearing 
aid  device. 


24 


INTERNATIONAL  PROJECTIONIST 


January  1949 


nard  N.  Pinzel,  exec,  board  at  large;  George 
Austin,  sgt.-at-arms;  Albert  F.  Ryde,  George 
O'Brien,  Hector  Stewart,  and  David  M. 
Hunter,  del.  Buffalo  Fed.  oj  Labor. 

LOCAL  310,  ATLANTIC  CITY,  N.  J. 

Wm,  Clendening,  pres.;  Richard  Mc- 
Sweeny,  vice-pres. ;  Vincent  J.  Sheeran,  rec- 
sec;  Wm.  Monroe,  fin.-sec;  Augustus  Hil- 
ton, bus.  rep.;  Wm.  Oliver,  sgt.-at-arms. 

LOCAL  348,  VANCOUVER,  CANADA 

Douglas  Calladine,  pres.;  Martin  Goble, 
vice-pres.;  J.  H.  (Hank)  Leslie,  sec;  Lloyd 
Pantages,  treas.;  R.  J.  (Bob)  Foster,  bus. 
rep.;  Ted  Foley,  recorder;  Fred  Wilson, 
member  at  large. 

LOCAL  376,  SYRACUSE,  N.  Y. 

Louis  R.  Boyd,  pres.;  Melvin  A.  Denny, 
vice-pres.;  George  F.  Raaflaub,  sec;  Lionel 
B.  Wilcox,  fin.  sec-treas.;  Harry  C.  Burley, 
bus.  rep.;  Lawrence  F.  Sherman,  John  H. 
Eccles,  Warren  Williams,  trustees;  Walter 
Scarge,  Philip  Rossomondo,  exec,  board; 
Wm.  H.  Maxon,  del.  Central  Labor  Union. 

LOCAL  521,  LONG  BEACH,  CALIF. 

Max  G.  Miller,  pres.;  Paul  King,  vice- 
pres.  ;  Alonzo  S.  Bennett,  sec-treas. ;  G.  A. 
Lahlum,  bus.  rep.;  Max  G.  Miller,  Paul 
King,  Alonzo  Bennett,  Frank  Knollmiller, 
L.  A.  Ward,  S.  B.  Wedell,  V.  G.  Martz,  exec, 
board;  D.  R.  Long,  Elmer  Hoik,  C.  E.  Ley- 
man,  Jr.,  trustees;  N.  D.  Owens,  R.  E.  Addy, 
Alonzo  Bennett,  exam,  board;  Peter  Heller, 
sgt.-at-arms. 

LOCAL  578,  MORGANTOWN,  W.  VA. 

A.  De  Fere,  pres.;  R.  D.  Herstine,  vice- 
pres.  ;  H.  D.  Kelly,  sec-treas. ;  C.  P.  De  Fere, 
bus.  rep.;  A.  Christy,  Ham.  Zehrbach,  0. 
Weaver,  trustees. 

LOCAL  644,  N.  Y.  C.  (Cameramen) 

Roy  Edwards,  pres.;  Fred  Fordham,  vice- 
pres.;  John  Visconti,  sec;  Jay  Rescher, 
treas.;  Walter  A.  Lang,  bus.  rep.;  Ed.  Hat- 
rick,  trustee;  Frank  Landi,  sgt.-at-arms. 

LOCAL  664,  VANDERGRIFT,  PENNA. 

Arthur  Cribbs,  pres.;  Frank  Dettore,  vice- 
pres.;  Albert  Sack,  bus.  agent;  Frank 
Kelley,  sec;  John  Protos,  treas.;  Herman 
Wegscheider,  Claude  Kepple,  Seward  Stiffler, 
trustees ;  Wm.  Rupert,  sgt.-at-arms. 


FLICKER  IN  MOTION  PICTURES 

(Continued  from  page  17) 

tional  series  inductance.  The  increased 
series  impedance  offers  a  further  ad- 
vantage in  that  the  arc  stability  is  im- 
proved. 

Independently,  engineers  involved  in 
the  frequency  conversion  to  60  cycles  in 
the  Southern  California  area  discovered 
the  same  trouble  when  flicker  appeared 
in  theatres  after  the  50-  to  60-cycle 
change.  The  inductance  design  has  been 
supplied  them  and,  to  date,  five  theatres 
have  been  equipped.  Reported  results 
state  that  the  improvement  amounts  to 
75  to  90%  elimination  of  visible  flicker 
due  to  this  source. 

To  forestall  serious  arc  flicker,  main- 


tenance men  have  been  supplied  with  a 
ripple  meter  which  is  arranged  prin- 
cipally to  measure  60-cycle  components. 

Conclusions  and  Recommendations 

After  discussing  flicker  sources  in 
production,  the  Grignon  paper  offers 
the  following  conclusions  and  recom- 
mendations: 

(1)  Steady  technical  improvement  in 
illumination  level  and  theatre  presenta- 
tion has  reached  the  point  where  future 
attention  must  be  directed  toward  im- 
proving mechanical  motions  and  provid- 


ing better  auxiliary  apparatus  and  ma- 
terials to  minimize  flicker  and/or  allow 
greater  latitude  in  usage  before  flicker 
becomes  apparent.  Nearly  all  elements 
in  the  basic  technical  motion  picture 
production  and  exhibition  system  have  in- 
sufficient margin  for  flicker-free  films. 

Over-all  Permissable  Variation 

(2)  The  sum  total  of  ail  variations  in 
the  system  which  produce  flicker  should 
not  exceed  2%.  However,  3%  variations 
may  be  temporarily  acceptable. 

(3)  Analytic  examination  of  film  proc- 
essing   and    incident    or    reflected    light 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


25 


(with  projector  running)  of  a  theatre 
screen  is  involved  and  difficult.  Me- 
chanical motions  can  be  best  studied  by 
measurement  of  instantaneous  velocity. 

(4)  Symmetrical  two-bladed  projec- 
tion shutters  producing  a  48-cycle  rate 
are  presently  acceptable  but  may  re- 
quire revision  if  illumination  is  in- 
creased appreciably. 

(5)  Arc-supply  apparatus  should  not 
contain  more  than  0.15%  of  60-cycle 
components  for  usual  line-supply  condi- 
tions and  practical  limits  of  equipment 
aging.  Series  inductance  is  desirable  for 
filtering  to  meet  these  requirements  and 
further  stabibzes  arc  burning.  Arc-sup- 
ply ripple  should  be  measured  periodic- 
ally to  indicate  proper  operation  and 
forestall  serious  nicker  from  this  source. 

(6)  Film  stock  has  introduced  flicker 
but  such  cases  are  apparently  random 
in  nature. 

Damping,  Filtering  Shutters 

(7 )  Nonuniform  shutter  velocities, 
either  camera  or  projector,  cause  flicker. 
Variations  up  to  7%,  peak  to  peak,  have 
been  measured  and  reproduced  for  an- 
alysis. Shutters  should  be  damped  or 
filtered.  Consequently,  future  work 
should  be  directed  along  this  line. 

(8)  Conventionally  controlled  camera 
motors  should  be  supplied  for  the  great- 


est practical  pull-out  power.  This  in- 
cludes synchronous  motors  controlled  by 
line  frequency. 

(9 )  In  so  far  as  possible,  flexible 
couplings  having  torsional  compliance 
should  be  avoided  but  if  this  is  imprac- 
tical or  impossible,  suitable  damping 
must  be  provided.  Flexible  couplings 
used  for  angled  drives  introduce  non- 
uniform motion  in  the  driven  member. 
Therefore,  this  type  of  mechanism  must 
be  avoided. 

(10)  All  film  propelling  or  handling 
mechanisms  must  be  kept  free  of  small 
periodic  bindings,  tight  spots,  or  other 
irregularities.-  This  rigid  requirement 
can  be  lessened  if  filtered  shutters  are 
provided. 

(11)  Work  should  be  initiated  to  in- 
vestigate the  effects  of  periodic  supply 
variation  on  photographic  illuminants 
and  the  flicker  resulting  therefrom. 

Periodic  Brightness  Differences 

(12)  A  study  should  be  made  to  pro- 
vide accurate  data  on  periodic  percepti- 
ble brightness  differences  as  a  function 
of  brightness,  frequency,  and  surround- 
ings. This  could  be  done  by  a  univer- 
sity or  medical  school,  but  since  the  in- 
formation is  peculiarly  applicable  to 
motion  pictures,  it  may  be  that  the 
SMPE  should  undertake  such  a  program. 

Undoubtedly,  in  the  foregoing  material 


it  has  been  noticed  that  many  branches 
of  this  subject  have  not  been  explored 
and  others  only  superficially  examined. 
This  is  an  indication  of  the  amount  of 
work  still  to  be  done  and  emphasizes 
the  need  for  broadened  and  accelerated 
activity  in  this  problem  of  motion  pic- 
ture production  and  presentation. 

HISTORICAL  SKETCH  OF  TV 

(Continued  from  page  11) 
tern  for  the  transmitter.  Sutton's  ap- 
paratus used  a  scanning  disk  and  a  light 
source  controlled  by  a  Kerr  cell.  This 
method  of  reassembling  the  image  was 
likewise  remarkable  in  that  it  was  used 
widely  in  practical  Tv  systems  for  nearly 
40  years. 

At  the  turn  of  the  century,  Sir  J.  J. 
Thompson,  in  his  work  to  determine  the 
charge-to-mass  ratio  of  the  electron, 
showed  that  the  cathode  ray  was  in 
reality  a  beam  of  high-speed  electrons. 
His  methods  involved  the  application  of 
both  electric,  and  magnetic  deflecting 
forces.  At  about  the  same  time,  Pro- 
fessor Braun  built  a  cold-cathode-ray 
tube.  With  it  he  could  show  the  effect 
of  magnetism  on  electron  beams  in  trac- 
ing their  paths  on  a  fluorescent  screen. 
From  the  viewpoint  of  Tv,  this  was  to 


Perfection  in  Projection 

is  Standard 
with  Super  Cinephor  Lenses 


Successful  theatre  operators  constantly  seek  perfection  in  projection. 
They  know  that  profits  are  dependent  on  projecting  sharp,  uniformly 
brilliant  screen  images.  That  is  why  the  overwhelming  majority  of 
new  theatres  shown  in  the  current  Theatre  Catalog  were  equipped 
with  Bausch  &  Lomb  projection  lenses.  Perfection  in  projection 
will  be  the  standard  in  your  theatres,  too,  if  you  use  Bausch  & 
Lomb  lenses.  Bausch  &  Lomb  Optical  Co.,  616-A  St.  Paul  St., 
Rochester  2,  N.  Y. 


BAUSCH  &  LOMB 


OPTICAL  COMPANY 


ROCHESTER  2,  N.  Y.. 


26 


INTERNATIONAL  PROJECTIONIST     •     January  1949 


be  the  means  of  scanning  control  for 
Crookes'  cathode  rays.  Amplitude  con- 
trol, on  the  other  hand,  was  to  come 
later. 

Sainton's  Basic  Conception 

By  the  end  of  the  first  decade  of  the 
20th  century,  Professor  Boris  Rosing 
had  patented  a  Tv  system,  using  a  re- 
ceiver resembling  the  modern  set,  based 
on  the  Braun  cathode-ray  tube.  In  1911, 
A.  A.  Campbell  Swinton,  a  man  of  great 
imagination  and  foresight,  saw  the  possi- 
bility of  Tv  communication  with  varia- 
tions of  Rosing's  cathode-ray  tubes  at 
both  transmitter  and  receiver.  Recent 
years  have  shown  that  Swinton  actually 
predicted  Tv  apparatus  as  used  today, 
having  developed  the  theory  of  a  cathode- 
ray-tube  camera.  Meanwhile,  Knudson 
had  sent  the  first  drawing  by  radio. 

Only  a  few  of  the  early  discoveries 
and  inventions  are  directly  employed  in 
modern  Tv.  However,  the  original  work 
and  inventions  gave  impetus  to  experi- 
ments in.  demonstrating  that  light  could 
be  converted  into  electrical  impulses 
which,  in  turn,  could  be  transmitted  and 
later  reconverted.  Fortunately  for  Tv, 
the  development  of  the  radio  and  elec- 
trical arts  coincided  with  the  advanced 
phases  of  research  in  the  fields  of  optics 
and  vision. 

Zworykin,  Baird  Contributions 

World  War  I  delayed  progress  uni- 
versally, for  the  next  important  date  is 
1923  when  Zworykin  filed  patent  appli- 
cation on  the  first  electronic  Tv  camera 
tube,  the  Iconoscope,  wherein  the  means 
for  scanning  control,  as  well  as  for  pic- 


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embracing  all  the  advantages  of  a  delightful 
boardwalk   hotel. 

Spacious  Colorful  Lounges — Sun  Tan  Decks 
atop — Open  and  inclosed  Solaria — Salt  Water 
Baths  in  rooms — Garage  on  premises.  Courteous 
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Exclusive   Penna.  Ave.  and   Boardwalk 


ture  signal-amplitude  control,  were  all 
self-contained  on  a  completely  electronic 
basis.  While  the  idea  had  been  proposed 
early  in  the  art,  this  was  the  first  prac- 
tical means  of  achieving  it. 

At  this  time  J.  L.  Baird  in  England, 
and  C.  Francis  Jenkins  in  the  United 
States,  working  independently,  produced 
and  demonstrated  Tv  systems  based  on 
mechanical  scanning  through  the  use  of 
the  Nipkow  disk  or  something  similar  to 
it.  The  disk  carried  holes  along  a  spiral 
in  such  a  way  that  a  scene,  when  viewed 
through  a  portion  of  it,  would  be  broken 
into  parallel  lines  or  arcs,  thereby  pro- 
viding the  means  of  measuring  light 
values  along  the  short  time-base  which 
represented  the  frame  interval.*  The 
pictures  were  mere  shadowgraphs  at  first, 
but  Baird  soon  demonstrated  Tv  trans- 
mission of  half-tone  pictures  as  well  as 
infrared  Tv. 

This  method  of  scanning,  having  seri- 
ous limitations  in  definition,  is  not  in 
use  today,  nor  is  the  receiving  system 
that  reconstructed  the  picture  by  revers- 
ing the  process.  While  the  low-definition 
(less  than  60-line)  images  of  those  days 
may  seem  to  have  little  bearing  on  tech- 
niques which  produce  present-day,  con- 
tinuous-tone pictures  in  a  525-line  sys- 
tem, much  of  the  theory  which  makes 
present  equipment  possible  was  proved 
during  this  mechanical  era. 

Wire,  Radio  Links  in  1927 

In  1927  the  Bell  System  demonstrated 
the  transmission  of  Tv  over  substantial 
distances;  between  Washington  and 
New  York  over  wire  line,  and  between 
Whippany,  N.  J.,  and  New  York  over 
radio  link.  With  this  was  published  an 
analysis,  thorough  for  the   time,  of  the 


transmission    problems    facing    Tv,    par- 
ticularly   the    frequency    bandwidth    re- 
quirements which  have  become  so  char- 
acteristic of  the  art. 
The    decade    1925   to    1935    produced 


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(SUCCESSOR  TO  FILM   CEMENT) 

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actually  welded  together. 
Applied  freely  to  film 
ends.  FILM-WELD  dis- 
solves film — fuses  it  into 
one  lasting  piece.  Easy  to 
use  for  hand  or  machine  splicing.  Re- 
tains its  strength! 

Use  FILM-WELD  to  patch  ALL 
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16  oz.  cans.  Follow  the  lead  of  pro- 
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are  already  PERMANENTLY  patch- 
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ZIPPER  CHANGEOVERS  to  guaran- 
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INTERNATIONAL  PROJECTIONIST     •     January  1949 


27 


many  developments  in  steady  succession. 
These  began  with  the  National  Broad- 
casting Co.'s  first  radio  network  and 
Warner  Brothers'  "Vitaphone"  sound-on- 
disk  system  synchronized  with  motion 
pictures.  Concurrently,  Congress  estab- 
lished the  Federal  Radio  Commission; 
progress  continued  with  Bairds'  first 
trans-Atlantic  Tv  picture  and  his  first 
crude  systems  of  color  and  stereoscopic 
Tv;  Farnsworth's  system  and  Zworykin's 
system   of   all-electronic    television   were 


E.  J.  HALEY— President,  Booker 
T  Theatres,  Raleigh,  North  Carolina 
— writes: 

"Sound  service  is  one  of  the 
vital  functions  of  successful 
theatre  operation.  We  have 
found  RCA  Service  to  be 
competent  and  responsible 
in  supplying  this  need." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


introduced  employing  special  cathode-ray 
receiver  tubes  called  kinescopes ;  Bell 
Laboratories  demonstrated  Tv  in  color, 
delivering  a  picture  of  postage-stamp 
size;  theater  Tv  was  shown  on  screens 
as  wide  as  10  feet;  two-way- wire  Tv- 
telephone  demonstrations  were  made  by 
Bell;  improved  photoelectric  cells  and 
electronic  tubes  were  introduced;  an  ex- 
tensive program  of  field  tests  by  RCA 
was  initiated  starting  with  240-line  all- 
electronic  television  employing  radio  re- 
lay, to  continue  right  through  the  period 
of  commercial  operation:  and,  finally, 
the  1935  announcement  of  the  principle 
of  frequency  modulation  by  Edwin  Arm- 
strong. 

Through  the  efforts  of  men  like 
Zworykin,  Engstrom,  and  Goldsmith  of 
RCA;  Farnsworth;  Ives  and  others  at 
American  Telephone  and  Telegraph  Co.; 
Alexanderson  of  General  Electric;  Du- 
mont;  and  Goldmark  of  Columbia  Broad- 
casting, well-planned  and  well-executed 
programs  made  public  participation  in 
the  U.  S.  A.  possible  in  1934. 

Coaxial  Cable  Introduced,  1936 

The  Philips  Co.  of  Holland  built  the 
first  iconoscope  in  Europe  in  1935.  Tv 
transmitters  appeared  in  places  such  as 
the  Eiffel  Tower  and  Stockholm.  As  the 
advance  continued,  A.  T.  and  T.  suc- 
cessfully demonstrated  the  capabilities  of 
coaxial  cables  in  1936.  Such  cables  were 
laid  from  New  York  to  Philadelphia, 
from  Paris  to  Bordeaux,  and  from  Berlin 
to  Nuremberg.  The  first  patent  on 
coaxial  cable  was  granted  in  England 
at  this  time,  and  cables  were  laid  from 
the    British    Broadcasting    Corp.    trans- 


U.  L.  approved  .  .  .  elimi- 
nates fire  hazard.  Micro- 
Switch  safety  cut-off — when 
door  opens,  motor  stops! 
Motor  does  not  transmit 
torque  to  operating  parts. 
Reel-drive  Dog... prevents 
broken  keys. 


Available  through  Theatre 
Supply  Dealers. 

GoldE  Manufacturing  Co. 

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^  Depl.  R,  Chicago  7 


Low  Maintenance  Cost 

• 

Positive  Friction  .  . . 
Will  Not  Clinch  Film 


Modern,  Compact  Design 

"Tilt-back"  Case  . .  . 
Reels  Can't  Fly  Off 


,y 


mitter  to  Buckingham  Palace  and  Vic- 
toria Station  for  the  first  direct  televis- 
ing of  coronation-procession  street 
scenes. 

In  1938  Tv  signals  from  London,  on 
ultra-short  waves,  were  picked  up  on 
Long   Island,   although   badly    distorted. 

The  point  was  reached  wherein  one 
saw  the  telecasting  of  plays  from  theater 
stages,  the  New  York  World's  Fair, 
major-league  baseball,  and  professional 
football.  Meanwhile  RCA  introduced  an 
improved  Tv  camera  tube,  the  Orthicon. 
It  is  beyond  the  scope  of  this  paper  to 
enumerate  the  many  developments  from 
that  point  to  date. 

The  lack  of  uniformity  in  choice  of 
number  of  lines  for  the  picture  struc- 
ture was  never  satisfactory  to  the  non- 
technical observer  who  was  quick  to 
compare  Tv  with  motion  pictures.  Be- 
cause of  this,  and  in  keeping  with  the 
steady  advances,  "definition"  was  stand- 
ardized at  343  lines  in  1935.  Later  this 
was  raised  to  441.  In  1940  it  was  in- 
creased to  525,  where  it  remains  as  to- 
day's standard. 

Although  World  War  II  brought  an 
apparent  period  of  inactivity,  an  abun- 
dance of  knowledge  and  technical  per- 
sonnel grew  out  of  government-sponsored 
radar  and  guided-missile  programs.  Ac- 
celerated research  and  development  pro- 
duced items  such  as  the  high-sensitivity 
image-orthicon  and  phosphors  to  with- 
stand the  bombardment  of  highly  accel- 
erated electron  beams,  for  brighter 
pictures. 

Color  vs.  Monochrome  Controversy 

The  highly  controversial  issue  of  color 
versus  black-and-white  Tv  brought  the 
industry  to  a  virtual  standstill.  After  this 
was  settled  early  in  1947  in  favor  of 
black-and-white,  the  prospective  broad- 
caster, the  equipment  manufacturer,  and 
the  receiving-set  purchaser  appeared 
ready  to  invest  in  the  fast-growing  busi- 
ness. 

By  December  31,  1947,  the  score 
totaled  12  cities  with  Tv  service;  18 
stations  operating  and  55  licensees ;  287 
sponsors;  142,400  receivers  in  private 
homes;  27,600  receivers  in  public  places; 
195,000  total  receiver  production;  and 
an  estimated  audience  of  1,200,000,  with 
assurance  of  nation-wide  networks  in  the 
reasonably  near  future. 

[Note:  Today  there  are  50  Tv  sta- 
tions on  the  air  spotted  in  32  cities 
through  25  states,  with  an  audience  of 
about  40  million  viewers  within  range 
of  more  than  a  million  receivers. 

It  is  estimated  that  during  1949  an- 
other 1,600,000  Tv  receivers  will  be  in 
use,  while  123  stations  will  be  broad- 
casting in  70  cities  through  35  states.  In 
1953,  Tv  people  assert,  there  will  be  17 
million  receiving  sets  for  an  audience  of 
60  million  people.— Ed.] 


28 


INTERNATIONAL  PROJECTIONIST 


January  1949 


SOUND  SYSTEM  ELEMENTS 

(Continued  from  page  8) 

arate  voltmeter  and  ammeter  readings) 
gives  the  power  factor: 

True  watts 


COS  (f)   =   

Volts  X  Amperes 
In    actual   practice  the    optimum   power 
factor  of  1  is  seldom  attained.  The  power 
factor   of   city   feeder   circuits   normally 
ranges  from  0.8  to  0.9. 

Effects  of  Capacitance 

Capacitance  also  throws  current  and 
e.m.f  out  of  phase,  reducing  the  power 
factor  and  tending  toward  wattless  cur- 
rent. When  a  condenser  is  supplied  with 
a-c,  the  current-peaks  lead  the  voltage 
peaks.  Curve  C  in  Fig  2  shows  a  90- 
degree  current  lead.  Although  this  con- 
dition is  never  attained  in  practice,  it 
may  be  approached  very  closely  in  a 
circuit  containing  a  large  capacitance. 

A  condenser  acquires  a  charge  while 
the  supplied  voltage  is  rising,  and  loses 
its  charge  while  the  supplied  voltage  is 
falling.  During  the  charge  period  the 
current-flow  is  in  the  same  direction  as 
the  voltage,  but  during  the  discharge 
period — which  begins  at  a  voltage-peak 
— the  current-flow  from  the  condenser  is 
opposite  in  direction  to  the  supplied 
e.m.f.  Hence,  the  current  changes  are 
said  to  lead  the  voltage  changes  in  a 
purely  capacitative  circuit  by  90  de- 
grees. 

It  is  easy  to  see  that,  even  though  cur- 
rent does  not  actually  flow  through  a 
condenser,  the  surge  of  electrons  in  and 
out  of  the  plates  results  in  an  alternating 
flow  in  the  circuit.  But  because  a  con- 
denser returns  very  nearly  as  much 
power  to  the  circuit  as  it  takes,  the  net 
power  consumption  is  0. 

Inductances  and  capacitances  may  be 
thought  of  as  devices  which  oppose 
changes  of  current.  Both  may  be  used 
to  absorb  surges  of  current  and  to  "fill 
in"  sudden  drops.  An  inductance  is  the 
electrical  equivalent  of  a  flywheel,  and 
a  capacitance  is  the  electrical  analog  of 
a  spring. 

Reactance 

The  effect  of  inductance  and  capaci- 
tance in  a-c  circuits  goes  by  the  name 
reactance.  There  are,  accordingly,  two 
kinds  of  reactance;  inductive  reactance 
and  capacitative  reactance.  Because  re- 
actance presents  an  opposition  to  cur- 
rent-flow it  may,  like  resistance,  be  meas- 


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ured  in  ohms.  But  whereas  the  flow- 
opposition  of  pure  resistance  consumes 
power  (watts),  reactances  return  power 
to  the  circuit,  and  therefore  use  up  no 
power — theoretically,  at  least. 

Pure  resistance  functions  in  a-c  cir- 
cuits in  the  same  way  as  in  d-c  circuits; 
hence  we  use  Ohm's  law  formulas  for 
calculating  it: 

E 

R  = 

I 

Curve  A  of  Fig.  2  shows  voltage  and 
current  in  the  co-phasal  relation,  a  con- 
dition which  obtains  perfectly  in  a  pure- 
ly resistive  circuit. 

The  reactance  of  an  inductor  or  capa- 
citor, unlike  the  resistance  of  a  resistor, 
varies  wtih  the  frequency  of  the  current, 
making  the  calculations  more  complex. 
Inductive  reactance  in  ohms,  XI,  is 
given  by  the  following  formula  in  which 
/  is  the  frequency  of  the  current  and  L 


is  the  inductance  in  henries: 

XI  -  2  7T  f  L 
while  the  ohmic  value  of  capacitative  re- 
actance, Xc,  is  given  by : 
1 

Xc  = 

2,rfC 
in  which  C  is  the  capacity  in  farads. 
When  using  these  formulas,  millihenries, 
microhenries,  etc.,  should  be  converted 
to  henries,  and  microfarads,  micromicro- 
farads,  etc.,  to  farads. 

When  several  inductors  or  capacitors 
occur  in  a  circuit  in  series  or  parallel,  it 
is  advisable  to  calculate  the  resultant  in- 
ductance or  capacitance  before  comput- 
ing the  inductive  or  capacitative  react- 
ance. Herewith  are  the  formulas  for 
these  calculations. 

Inductors  in  series: 

L  =  lt  +  1,  +  ls  +  •  •  • 
Inductors  in  parallel: 


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1         1 

1 

—  +  —  + 

-+  .  . 

ll      1, 

1. 

Capacitors  in  series: 

1 

c  — 

1              1 

1 

+ +  - 

+  .  .  . 

Cl  C2  C3 

Capacitors  in  parallel: 

C  =  c±  +  c2  +  c3  +  .  .  . 

Net  Reactance 

Net  reactance,  X,  signifies  the  result- 
ant reactance  of  two  or  more  reactances 
■ — inductive,  capacitative,  or  both.  In 
all  cases  where  several  reactances  of  the 
same  kind  (either  inductive  or  capacita- 
tive, not  both)  are  connected  in  series, 
the  total  reactance  is: 

X  =  xx  +  x2  +  x3  +  .  .  . 

but  if  the  "like"  reactances  are  connected 
in  parallel,  the  net  is  given  by  the  fol- 
lowing: 

1 
X  = 


+ 


+ 


+ 


Al  x2  X3 

You  will  recall  similar  formulas  for  re- 
sistances in  series  and  parallel. 

Now  if  two  groups  of  reactances,  one 
inductive  and  the  other  capacitative,  be 
connected  in  series,  the  net  reactance  is 
obtained  by  subtracting  the  lesser  react- 
ance from  the  greater.  (In  the  following 
formula  it  is  assumed  that  the  inductive 
reactance  is  numerically  the  greater)  : 

X  =  XI  —  Xc 

When  a  circuit  consists  of  pure  re- 
actance (reactance  wtihout  resistance), 
we  may  find  the  ohmic  value  of  the  re- 
actance by  substituting  X  for  R  in  the 
familiar  Ohm's  law  formula: 

E 

X  = 


I 

Consequently,  voltage  and  current  in   a 
reactive  circuit  are  given  by: 


E 


E  =  IX    and    I  =  — 
X 

Total  Impedance 

Because  of  the  fact  that  pure  resist- 
ance is  ordinarily  found  in  a-c  circuits 
in  conjunction  with  reactance,  formulas 
for  total  impedance  are  especially  useful 
in  sound-system  work.  Impedance,  Z, 
signifies  the  combined  current-impeding 
effects  of  resistance  and  both  kinds  of 
reactance,  and  is  also  measured  in  ohms. 

If  the  effective  voltage  and  amperage 
in  a  series  circuit  are  known,  impedance 


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and  the  ohms  of  net  reactance  in  a  series 
circuit,  impedance  may  be  calculated  by: 


is  given  by  substituting  Z  for  R  in  Ohm's 
formula : 

E 
Z  =  — 
I 

It  follows  that  voltage  and  current  in  an 
alternating-current  circuit  may  be  found 
by  transforming  this  equation  into  the 
following  two  forms. 

E 
E  =  IZ  I  =  — 

Z 

When  we  know  the  ohms  of  resistance 


Z  =  V  R2  +  X2, 
in  which  X2  equals  (XI  —  Xc) 2. 

Calculating  the  total  impedance  of  re- 
sistances and  reactances  in  parallel  ar- 
rangements poses  a  slightly  more  diffi- 
cult problem.  Here  is  the  easiest  way 
to  do  it. 

We  shall  assume  that  the  resistive  and 
reactive  branch  circuits  each  receive  the 
same  voltage,  so  we  first  calculate  the 
amperes  flowing  in  each  branch: 

Resistive:  Inductive:  Capacitative: 

E  E                     E 

iR  =  —  *X1  =  —  !Xc  =  — 

R  XI                    Xc 

We  next  combine  the  reactive  currents, 
subtracting  the  smaller  from  the  greater: 

IX  =  1X1  —  iXc 

and  the  values  of  7i?  and  lX  are  then1 
used  in  the  following  final  formula  which 
gives  the  total  impedance  in  ohms: 


E 


Z  = 


V  *R2  +  XX2 

An  appreciation  of  these  formulas  and 
of  the  electrical  quantities  involved 
therein  will  provide  a  sufficiently  good 
understanding  of  alternating  currents  to 
enable  us  to  proceed  directly  to  an  ex- 
amination of  amplifier  circuit-coupling 
methods. 

[To  be  Continued] 


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Every  projectionist  should  know  the  whys  and  where- 
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show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


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illustrated  with  schematic  diagrams. 


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of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
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Sometimes 
women  have  to 
cany  the  banners 


PERHAPS  you'll  see  the  story  of  Joan  of 
Arc,  as  portrayed  on  the  screen  by  Miss 
Ingrid  Bergman. 

It's  a  thrilling  episode  in  the  world's  history, 
proving  that  sometimes  a  woman  must  take  the 
lead  in  the  fight  she  believes  in. 

Modern  women,  too,  must  often  pick  up  the 
banners  ...  in  their  struggle  for  the  security  and 
well-being  of  their  family. 

Though  earning  the  necessities  of  life  is  pri- 
marily a  man's  job,  sometimes  it  takes  a  woman 
to  insure  her  family's  future  by  setting  them  on 
the  only  sure  road  to  security  . . .  through  ade- 
quate, regular  savings. 

For  the  modern  woman,  there  is  one  fool- 
proof method  of  winning  her  fight  for  savings. 
It's  United  States  Savings  Bonds— an  invest- 
ment with  the  soundest  backing  in  the  world 
...  an  investment  that  pays  back  four  dollars 
for  every  three. 

And  there  are  two  foolproof  savings  plans, 
too.  One  is  the  Payroll  Savings  Plan,  for  those 
on  a  company  payroll.  The  other  is  the  Bond- 
A-Month  Plan,  for  those  not  on  a  payroll, 
whereby  bonds  are  purchased  through  the 
checking  account. 

If  your  home  is  your  career,  urge  your  husband, 
and  all  other  working  members  of  your  family, 
to  start  now— today— on  the  bond-saving  plan 
for  which  they  are  eligible. 

If  you  are  working,  sign  up  yourself  at  your 
firm  or  bank,  and  influence  the  other  working 
members  of  your  family  to  do  the  same. 

Soon  the  bonds  will  start  piling  up. 

Soon  you'll  know  that  confidence  in  the  fu- 
ture which  only  comes  through  saving. 

It's  a  wonderful  feeling  for  anyone.  And  for 
a  woman — how  doubly  wonderful! 

AUTOMATIC  SAVING 

IS  SURE  SAVING 
U.S.  SAVINGS  BONDS 


Contributed  by  this  magazine  in  co-operation  with  the 
Magazine  Publishers  of  America  as  a  public  service. 


(SJCIB    177278 


RCA  Mepe^ 
At  Yoor  Rt*  Ver 

TheoHeSuppW" 


B-*-^  "  i.  Carpets  s 

?SsSr^Sd^u»p» 

X?estiogbousefluoresce0tLamP 

KCr%^ePUcementPa- 
Service  a«"  ^^^^^^ 


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For  the  pleasing  and  realistic  tone  balance  that  pays  off  at  the 
box  office  — choose  an  RCA  Stage  Loudspeaker  System. 

It  reproduces  voices,  music  and  sound  effects  so  clear  and 
lifelike  .  .  .  distributes  the  sound  so  uniformly  throughout  the 
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though  they  were  listening  to  an  original  studio  performance. 

HIGH-FREQUENCY   LOUDSPEAKER 

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18-cell  construction  enables  you  to  select  the  horn  best  fitted  to 
minimize  acoustical  troubles  due  to  shape  of  your  auditorium. 
High-frequency  mechanisms  reproduce  faithfully  the  very  highest 
notes  to  achieve  lifelike  realism. 

LOW-FREQUENCY   LOUDSPEAKER 

A  massive  horn  provides  well-rounded  bass  reproduction.  Highly 
efficient  oversize  mechanisms  reproduce  the  lowest  tones  that 
delight  theatre  patrons.  A  minimum  of  depth  behind  the  screen 
is  required  for  installation. 

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respect  and  praise  of  theatre  owners  and  operators  all  over  the 
world.  There  is  an  RCA  Stage  Loudspeaker  System  that  will  bring 
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See  your  RCA  INDEPENDENT  THEATRE 
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mm 

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HERE'S  THE  INCREASED  LIGHT 

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DRIVE-IN  &  LARGE 
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THE 

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REFLECTOR 

TYPE  ARC 

LAMP 


Operating  at  85  amperes,  the  Motiograph-Hall  produces  19,000  lumens — 
more  light  than  condenser-type  high  intensity  lamps  operating  at  more 
than  twice  this  amperage. 

Precise  positioning  of  the  carbons  with  respect  to  each  other  holds 
the  gases  within  the  crater  where  they  become  superheated  to  extreme 
brilliancy.  A  rotating  positive  carbon  (the  only  reflector-type  lamp  with 
this  feature)  permits  even  burning  of  the  carbons  and  a  proper  crater 
form,  at  75  to  115  amperes. 

The  efficiency  of  the  reflector-system  in  collecting  and  focusing  the 
light  on  the  picture  aperture  is  admittedly  superior  to  that  of  the 
condenser-type  lamps.  Employs  a  16"  mirror,  the  largest  of  any  reflector- 
type  lamp.  The  reflector  holder  is  permanently  mounted  so  as  to  form 
the  rear  door  of  the  lamphouse,  rendering  perfect  optical  alignment 
of  the  reflector,  aperture  and  lens  at  all  times. 

Some  lamps  require  a  glass  heat  filter  between  the  lamp  and  the 
projector  to  prevent  film  buckling.    These  filters,  however,  also  reduce 


the  amount  of  visible  light  passed  so  that  little,  if  any,  more  reaches 
the  screen  than  is  obtained  from  a  lesser  light  source. 

Due  to  the  extremely  high  intrinsic  brilliancy  of  the  Motiograph-Hall 
arc,  the  total  light  output  contains  a  much  larger  percentage  of  visible 
light,  making  the  use  of  a  filter  unnecessary. 

The  automatic  focus  control,  an  exclusive  feature,  constantly  holds 
the  crater  of  the  positive  carbon  at  the  exact  focal  point  of  the  mirror 
preventing  variations  in  the  character  of  the  light  at  the  screen. 

When  the  current  approaches  2%  above  normal  or  falls  to  1  %  below 
normal,  a  pilot  light  flashes  and  the  arc  control  automatically  corrects 
the  gap  length.   Constant  adjustment  of  manual  controls  is  unnecessary. 

The  Motiograph-Hall  lamp  is  designed  to  use  9  mm.  or  11  mm.  high 
intensity  positive  carbons  and  5/16"  negative  carbons,  the  cost  of 
which  is  about  one-third  that  of  the  cost  of  the  larger  carbons  used  in 
condenser-type  lamps  operating  in  the  140-180  ampere  range. 


Other  Motiograph  products  include  Motiograph  1  K.W.  and  46-ampere  high 
intensity  arc  lamps,  Motiograph  projectors,  indoor  and  outdoor  sound 
systems,  generators  and  rectifiers,  in-car  speaker  equipment  and  junction 
boxes,  ramp  switching  panels  for  drive-ins,  turntables,  etc. 


Literature  and  complete  information  may  be  obtained  from 


mouoGRAPH,  inc., 


4431     W.     LAKE     ST.,     CHICAGO     24,     ILL 


INTERNATIONAL  PROJECTIONIST 


February  1949 


INTERNATIONAL 


ROJECTION! 


With  Which  Is  Combined  Projection  Engineering 


. 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


FEBRUARY  1949 


Number  2 


Index  and  Monthly  Chat   5 

Coated  Lenses:  Nature  and  Care     7 
A.  E.  Murray 

The  Mechanism  of  Hearing   ...      10 

Sound  System  Components,  IV       12 
Robert  A.  Mitchell 

The  New  M-G-M  Steropticon   .16 
Merle  Chamberlin 

Addendum:  SMPE  Papers 

Abstracts  16 

Color:  Its  Complex  Structure    ...    17 
Dr.  Herbert  Meyer 

Stability  vs.  Chaos  in  Tv 18 

Dr.  Alfred  N.  Goldsmith 

Strobo  Discs  for  Both  60-  and 

50-Cycle  Power  Supply 18 


New  Motiograph-Hall  H-I  Lamp.    19 

In  the  Spotlight 20 

Harry  Sherman 

P.  A.  McGuire  Feted  by  25-30     .    22 

Condensers  in  Combination  with 

Coils       23 

A.  Buckley 

Nine  New  American  Standards 

Announced  by  SMPE   24 

Telecasts    25 

IA  Elections   32 

Personnel    33 

Presenting:  David  E.  Day, 

Local  110   34 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
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INTERNATIONAL  PROJECTIONIST     •     February  1949 


MONTHLY   CHAT 

IP  HAS  always  approved  and  even  en- 
couraged the  most  extensive  field-testing 
of  equipment  intended  for  general  use  in 
theatre  projection  rooms,  experience  hav- 
ing demonstrated  that  even  the  most  in- 
tensive laboratory  or  in-factory  testing 
not  infrequently  fails  to  disclose  operat- 
ing deficiencies  which  manifest  them- 
selves when  once  the  unit  is  operated  in 
the  field. 

IP  is  almost  invariably  privy  to  such 
testing  operations,  whether  in  the  fac- 
tory or  out  in  the  field,  and  it  has  never 
knowingly  abused  the  confidence  of  any 
manufacturer  with  respect  to  these  pro- 
ceedings. Of  late,  however,  there  has 
developed  a  tendency  on  the  part  of 
certain  manufacturers  to  effect  the  transi- 
tion of  a  given  unit  from  the  "experi- 
/  mental"  to  the  commercial  stages  under 
a  blanket  of  secrecy  which  is  hardly 
flattering  to  the  unit  involved.  The  first 
intimation  that  IP  has  that  such  units 
are  available  is  when  its  readers  write  in 
to  inquire  about  certain  characteristics 
of  the  equipment. 

Now,  IP's  function  is  obviously  that 
of  disseminating  information  as  speedily 
and  in  such  detail  as  will  gain  and  hold 
the  interest  of  its  readers.  It  is  cer- 
tainly not  to  IP's  benefit  —  nor  to  the 
benefit  of  the  craft  in  the  long  run — for 
various  units  to  be  slipped  into  circula- 
tion in  a  manner  that  approaches  the 
surreptitious.  All  too  often  has  IP  first 
learned  of  the  commercial  status  of  a 
hitherto  "experimental"  carbon  trim,  or 
a  lamp,  or  other  projection  unit  via  a 
series  of  letters  from  projectionists  in 
the  area  selected  by  the  manufacturer 
as  a  point  of  penetration. 

Then  unfolds  the  all  too  familiar  pat- 
tern: some  months  later  there  descends 
upon  IP  a  packet  containing  reams  of 
copy  and  a  sheath  of  glossy  prints  the 
"generous"  use  of  which  is  requested  by 
the  manufacturer  of  this  "new"  equip- 
ment. This  after  IP's  people  have  been 
using  the  equipment  for  many  weeks 
and,  likely  as  not,  a  detailed  exposition 
of  the  unit  has  been  made  before  an  "en- 
gineering" society  among  the  members 
of  which  there  are  few,  if  any,  "live"  cus- 
tomers. 

Such  a  procedure  adds  up  in  IP's 
offices  to  a  lot  of  malarkey,  a  sort  of  edi- 
torial stew  that  IP  cannot  and  will  not 
longer  digest.  IP  considers  it  necessary 
to  offer  its  own  definition  of  the  word 
"experimental,"  as  follows: 

That  unit  may  be  considered  to  be  in 
the  "experimental"  stage  which  has  not 
yet  been  offered  for  sale.  The  moment  a  ' 
given  unit  is  offered  for  sale  it  becomes 
a  "commercial"  item  and  as  such  will  be 
subjected  to  appraisal  by  IP,  with  or 
without  the  manufacturer's  assent.  This 
definition  presages  a  bit  of  rough  going 
for  some  of  the  "cute"  manufacturers, 
but  their  discomfiture  will  not  alter  one 
whit  IP's  determination  to  serve  its  own 
best  interests  by  serving  its  readers  best. 


"National"  high  intensity 
carbons  change  dim  screen 


0CLOl**T 


to  bright  screen 


ihd  make  box  office 


"NATIONAL"  H.I.  ARC- 

"BRIGHTEST  SPOT  IN  THE  WORLD' 


The  term  "National" 
is  a  registered  trade -mark  of 

NATIONAL  CARBON  COMPANY,  INC. 

Unit  of 
Union  Carbide  and  Carbon  Corporation 

30  East  42nd  Street,  New  York  17,  N.  Y. 

Division  Sales  Offices: 
Atlanta,  Chicago,  Dallas,  Kansas  City, 
New  York,  Pittsburgh,  San  Francisco 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


INTERNATIONAL    PROJECTIONIST 


VOLUME  XXIV 


FEBRUARY  1949 


NUMBER  2 


Coated  Lenses:  Nature  and  Care 


THERE  seems  to  be  an  elfish,  mis- 
chievous, almost  malicious  spirit 
about  modern  technology:  we  no 
sooner  adapt  ourselves  to  an  innovation, 
learning  its  idiosyncracies,  its  own  pe- 
culiar little  laws  the  better  to  pay  it  its 
due  respect  and  to  gather  from  it  all  it 
can  give,  than  another  comes  along  with 
its  own  set  of  eccentricities  which  on  the 
basis  of  chance  cannot  be  identical  with 
those  already  painfully  learned,  and  the 
whole  wasteful  process  of  learning  by 
error  must  be  started  afresh. 

Just  such  a  development  apparently 
has  been  witnessed  in  the  field  of  optics 
within  the  past  ten  years  with  the  intro- 
duction of  coated  lenses.  The  care  of 
high-grade  lenses,  learned  through  count- 
less mistakes,  was  fairly  well  understood, 
to  judge  from  the  reports  received  by  the 
manufacturers,  until  the  whole  field  was 
turned  topsy-turvy  by  the  development 
on  a  commercial  scale  of  the  techniques 
of  applying  anti-reflection  films. 

Lens  Mistreatment  Widespread 

The  manufacturer  now  receives  lenses 
showing  indisputable  evidence  of  mis- 
treatment, the  result  of  either  ignorance 
or  sheer  carelessness  which,  for  the 
most  part,  seems  inexcusable.  He  is 
somewhat  more  than  a  bit  perturbed  to 
see  these  lenses  in  such  a  condition,  for 
aside  from  a  natural  pride  in  a  well-made 
product,  repairs  cannot  in  the  lo»g  run 
be  profitable,  for  they  are  at  best  stop- 
gap and  the  manufacturer's  reputation 
inevitably  suffers. 

It  is  to  alleviate  some  of  these  troubles 
that  this  article  was  prepared,  and  it  is 


By  A.  E.  MURRAY 

Scientific  Bureau 
Bausch  &  Lomb  Optical  Company 

hoped  that  those  who  handle  the  really 
excellent  lenses  of  today  will  gather 
from  it  a  better  understanding  of  the 
physical  nature  of  that  extremely  thin 
boundary  between  air  and  glass  which  has 
such  a  profound  effect  on  the  optical 
properties  of  the  objective  elements. 

The  extent  to  which  most  optical  glass 
is  delicate — and  therefore  subject  to 
scratching  by  an  astonishing  array  of 
things  we  have  learned  to  think  of  as' 
truly  soft — -is  not  realized  except  by  those 
who  have  seen  the  effect  of  common  dust 
rubbed  over  a  polished  optical  glass  sur- 


Coarse   emery  particles   at   12x  magnification. 
These  sharp  particles  are  used  in  grinding  lenses. 


face.    Once  seen,  such  a  demonstration 
cannot  be  forgotten. 

The  accompanying  illustrations  are 
photomicrographs  of  emery  grains  and 
common  dust — not,  however,  to  the  same 
scale.  The  first-named  substance  is  used 
to  grind  curves  on  lenses;  its  abrasive 
qualities  are  commonly  known.  The  sec- 
ond produces  scratches  in  fine  optics,  its 
multitude  of  sharp  edges  being  hint 
enough  of  the  hazard  in  indiscriminate 
rubbing  over  a  dust-laden  polished  sur- 
face. 

Even  Bland  Substances  Unsatisfactory 

Even  such  a  bland  substance  as  face 
power  is  capable  of  producing  scratches 
sufficient  to  destroy  the  fine  polish  labori- 
ously applied  at  the  factory.  Individu- 
ally, such  scratches  exert  a  negligible 
effect,  but  multiplied  many  times  over 
so  as  to  cover  the  entire  lens  surface,  they 
can  be  disastrous  to  good  imagery  and 
contrast  on  the  screen. 

All  cleaning  powders  contain  such 
abrasive  matter,  despite  assertions  that 
they  never  scratch,  and  are  thus  never 
to  be  used  to  clean  a  lens,  coated  or  un- 
coated.  This  homely  little  principle 
seems  to  be  well  enough  understood  by 
the  majority  of  projectionists  and  pho- 
tographers. 

The  introduction  of  filmed  optics  has 
not  changed  substantially  the  recom- 
mended cleaning  practices,  but  it  has 
brought  with  it  a  new  factor  in  the  in- 
creased sensibility  of  the  filmed  surface 
to  contamination  of  any  kind. 

The  surface  reflectances  of  most  sub- 
stances likely  to  be  found  spread  on  a 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


lens  approach  that  of  the  glass  itself 
and  thus  would  not  be  easy  to  see  against 
the  surfaces.  A  thin  uniform  layer  of 
water  is  totally "  unrecognizable  against 
.glass  until  it  loses  its  uniformity,  i.e., 
begins  to  evaporate  or  to  flow  off,  when 
the  varying  thickness  betrays  it. 

Coated  Surfaces  More  Demanding 

The  story  is  totally  different  with 
coated  surfaces.  The  reflectance  here  is 
so  low  that  a  drop  of  liquid  of  any  kind, 
oil  or  water,  is  instantly  manifest  as  a 
grossly  different  area,  a  horrid  spot  quite 
out  of  keeping  with  the  rest  of  the  sur- 
face, a  disfiguring  area  that  demands  re- 
moval because  of  its  heretical  reflectance. 

Coated  surfaces  are  no  more  difficult 
to  clean  than  the  unfilmed  ones:  the 
penalty  of  incomplete  or  careless  clean- 
ing is  simply  more  evident.  Exactly  the 
same  amount  of  elbow  grease,  properly 
applied,  is  required  to  make  an  unfilmed 
surface  clean  as  to  perform  the  same  duty 
for  a  coated  one — the  only  difference 
being  that  with  the  latter  the  residue 
likely  to  be  overlooked  in  the  uncoated 
lenses  just  cannot  be  tolerated,  since  it 
will  obtrude  itself  painfully. 

Moreover,  the  filmed  surface,  or  the 
substance  applied  to  produce  the  anti- 
reflection  properties,  demands  the  same 
careful  treatment  as  does  the  original 
glass  surface.  In  fact,  the  magnesium 
fluoride  commonly  applied  has  a  chemi- 
cal inertness  exceeding  that  of  many  of 
the  optical  glasses.  It  thus  can  stand 
attack  by  stronger  chemical  cleaning 
agents  than,  in  many  cases,  the  glass 
itself. 

But  this  circumstance  is  slight  con- 
solation indeed,  for  no  strong  agents  can 
be  used  in  the  cleaning  process  because 
of  the  other  substances  used  in  making 
lenses — the  metal  mounts,  the  optical 
cements,  and  even  the  lacquer  used  to 
cut  down  reflections. 

Coatings  Hard  But  Thin 

Similarly,  the  hard  coatings  in  their 
mechanical  properties  are  as  scratch- 
resistant  as  most  optical  glasses.  This 
statement,  while  true  in  itself,  is  woefully 
misleading.  The  coating  may  be  as  hard 
but  it  cannot  be  as  thick ;  and  as  we  have 
already  seen  that  glass  itself  is  soft,  the 
coating  may  be  destroyed  surprisingly 
easily  by  abrasion,  which,  of  course, 
means  the  loss  of  anti-reflecting  prop- 
erties. 

The  net  consequence  of  all  this  is  that 
coated  surfaces  should  be  treated  with 
the  same  degree  of  gentleness  as  is  glass. 
Under  no  circumstances  are  abrasives  to 
come  into  contact  with  lenses,  coated  or 
uncoated:  their  effect  is  no  greater  on 
the  one  than  on  the  other,  but  is  simply 
more  readily  recognized  in  the  filmed 
surfaces. 

Investigation   at  Bausch  &  Lomb  has 


Dust  of  unknown  origin  at  lOOx  magnification. 
The  hazard  involved  in  rubbing  this  air-borne 
dust  over   highly  polished   surfaces   is   obvious. 

shown  that  the  best  cleaning  agents  for 
lens  surfaces,  both  filmed  and  unfilmed. 
are:  (1)  a  gentle  blast  of  air;  (2)  a 
camel's  hair  brush;  (3)  a  soft  cloth 
properly  used;  (4)  the  film  of  moisture 
from  the  breath  together  with  a  soft 
cloth;  (5)  warm,  not  hot,  pure  or  dis- 
tilled water;  (6)  most  of  the  common 
detergents  (the  commercial  "soapless 
soaps"  such  as  women  use  for  sheer  lin- 
gerie), and  (7)  warm  water  suds  of  the 
mildest  soaps  such  as  are  suitable  for 
babies. 

The  use  of  any  of  these  agents  should 
be  followed  by  rinsing  in  pure  warm 
water. 

Solvents  Strictly  a  Last  Resort 

When  all  else  fails,  and  strictly  as  a 
last  resort,  one  is  confronted  with  the 
use  of  solvents  such  as  alcohol — and 
even  at  this  point  solvents  should  be  used 
very  sparingly. 

The  use  of  alcohol  is  the  most  drastic 
treatment  to  which  lenses  can  be  sub- 
jected and  is  always  attended  by  consid- 
erable danger.  A  manufacturer  just 
cannot  recommend  solvents  for  the  clean- 
ing of  his  lenses,  even  in  the  most  skillful 
hands,  and  he  is  fully  justified  in  refus- 


LENS  CLEANING  RULES 

1.  Remove  dust.  (Blow,  brush 
or  wipe  off) 

2.  Clean  with  water,  detergent 
solution,  or  mild  soap.  Rinse 
scum-free. 

3.  Always  use  dust-free  cloths, 
cotton,  or  lens  tissues. 

4.  Never  use  cleaning  powders. 
Post  These  Rules  for  Ready  Reference 


ing  responsibility  for  any  damage  result- 
ing therefrom. 

The  techniques  discussed  in  the  re- 
mainder of  this  article,  familiar  in  their 
broad  outlines  to  the  reader,  will  have 
their  emphasis  on  the  reason  why  rather 
than  the  what. 

The  very  important  first  step,  without 
which  all  that  follows  is  unavailing,  is 
the  removal  of  every  particle  of  dust  from 
the  lens  surfaces.  If  this  is  not  done, 
serious  consequences  are  likely  to  ensue; 
moreover,  in  a  majority  of  cases  this  is 
all  the  treatment  necessary  to  restore  a 
dirty  lens  to  its  original  efficiency.  But 
the  removal  process  requires  extreme 
care  if  it  in  itself  is  not  to  produce  marks. 

Efficient  Cleaning  Procedure 

The  most  efficient  manner  of  cleaning 
a  lens  is  to  blow  the  dust  off,  using  a 
syringe,  or  even  the  breath.  If  dust  par- 
ticles still  linger,  as  is  likely,  particu- 
larly if  one  attempts  to  blow  it  away,  a 
soft  camel's  hair  brush  will  pick  up  what 
remains.  The  brush  should  be  tapped  on 
the  edge  of  the  table  after  each  pass  in 
order  to  shake  out  the  grit  and  dust 
particles  picked  up  from  the  lens  surface. 

It  is  also  possible  to  remove  this  dust 
by  the  use  of  a  cloth  wrapped  about  the 
finger.  The  cloth  must  be  very  soft,  re- 
cently laundered  and  scrupulously  clean, 
if  it  is  not  to  introduce  its  own  dust  and, 
what  is  more  annoying,  lint.  An  alterna- 
tive choice  is  lens  tissue,  available  at 
camera  stores. 

The  trick  is  to  wipe  across  the  surface 
gently  by  rotating  the  finger  and  the 
cloth  so  as  to  pick  up  the  dust  and  re- 
move it  from  the  contact  point.  If  the 
motion  is  across  the  glass  surface  from 
right-to-left,  the  cloth-wrapped  finger 
should  be  rotated  clockwise;  for  left- 
handed  people,  counter-clockwise  rota- 
tion is  indicated. 

Once  the  dust  is  removed,  the  proce- 
dure is  straightforward.  It  will  be  found 
that  usually  the  film  of  moisture  depos- 
ited by  breathing  gently  on  the  lens, 
when  removed  by  careful  rubbing,  will 
take  with  it  the  remainder  of  the  scum 
and  dirt. 

If  this  does  not  suffice,  it  may  be  nec- 
essary to  try  heavier  doses  of  water  ap- 
plied to  the  affected  areas  by  a  cloth 
wrung  nearly  dry,  or  by  small  pieces  of 
surgical  cotton  wrapped  on  a  toothpick 
or  suitable  stick,  followed  by  a  piece  of 
dry  cotton  or  cloth  to  remove  the  excess 
water  and  to  dry  the  surface. 

The  Use  of  Detergents 

If  water  itself  does  not  do  the  trick, 
resort  to  stronger  agents  is  indicated. 
The  very  best  of  these  is  some  common 
detergent  dissolved  in  clean  warm  water 
in  the  proportions  of  one  tablespoonful 
to  the  gallon.  If  this  fails,  the  next 
strongest  agent,  and  the  last  that  can  be 


8 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


THE  STRONG  UTILITY 

1    KW.  HIGH  INTENSITY 

PROJECTION  ARC  LAMP* 


FOR    TWICE    THE    LIGHT    ON 
SCREENS     UP     TO     18     FEET 

* 
There  are   more   Strong-made 
D.C.  1  KW.  lamps  used  today 
than  all  other  makes  of  1  KW. 
lamps  combined. 


The  only  projection  lamps  produced  complete  within  one  factory. 


USE  THIS  COUPON  TODAY  FOR  DEMONSTRATION  OR  LITERATURE 


<   THE  STRONG  ELECTRIC  CORPORATION 

|   87  City  Park  Avenue  Toledo  2,  Ohio 

I  |^}  I  would  like  a  demonstration  of  Strong  lamps  in   my  theatre,  without  cost  or 

obligation. 

'J  Please  send  free  literature  on  the: 

I    |  Mogul  Lamp  ]   Utility  Lamp  Q  Strong  Arc  Spotlamps 

I         fj]  Strong  Rectifiers  Q  Strong  Reflectors 


NAME 


1   THEATRE- 
>   STREET — 


CITY   AND   STATE 


ItikeH-tAe iatHf*  <m  STRONG  -Me/otrfate  it  kjfa. 


/ 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


recommended,  is  copious  suds  of  a  gentle 
soap.  The  use  of  these  agents  should 
always  be  followed  by  a  thorough  rinse 
with  clean  water,  preferably  lukewarm, 
and  drying  as  aforementioned.  By 
"rinse"  is  understood  the  application  of 
clean  water  on  a  nearly  dry  cloth  or 
cotton-wrapped  stick  or  toothpick;  it 
does  not  mean  to  flush  with  water. 

No  commercial  cleaning  fluid  is  rec- 
ommended by  Bausch  &  Lomb  for  the 
cleaning  of  high-grade  lenses  because 
they  all  are  in  essence  the  same  solution, 
as  described  in  the  preceding  paragraph. 
There  is  no  point  in  paying  for  a  product 
which  is  99%  water.  One  can  make  his 
own  lens  cleaning  solution  which,  while 
it  may  not  bear  a  fancy  label  and  a  spe- 
cious guarantee,  will  be  no  less  effective 
in  removing  dirt. 

Emergency  Cleaning  Methods 

There  may  be  especially  obstinate 
cases  when  more  vigorous  methods  are 
required,  as  when  a  lens  has  fallen  into 
a  barrel  of  oil,  been  splashed  with  paint, 
or  been  smeared  with  tar  or  some  other 
equally  stubborn  substance.  When  these 
rare  cases  arise,  such  solvents  as  alcohol, 
carbon  tetrachloride,  lighter  fluid,  or  the 
finest  laboratory  petroleum  distillates 
may  be  used  with  the  understanding  that 
they  entail  considerable  potentiality  of 
damage  to  both  the  lens  and  its  mount. 

These  solvents  must  be  used  extremely 
sparingly,  never  with  enough  to  wet  the 
cotton  or  cloth  applicator,  for  the  excess 
is  likely  to  find  its  way  into  the  interior 
of  the  lens,  there  to  attack  the  cement 
and  induce  rapid  deterioration.  Another 
danger  in  the  excessive  use  of  solvents 
is  the  immanent  possibility  of  irrepar- 
able damage  to  the  seal.  Of  course,  such 
liouids  cannot  be  kept  from  the  mount, 
where  they  attack  the  lacquer  and  reveal 
the  bare  metal,  thus  increasing  the  con- 
trast-robbing light  scatter. 

Always  after  using  these  solvents  the 
lens  should  be  carefully  cleaned  with 
mild  soap  and  water  to  remove  the  last 
trace  of  scum  which  remains  after  dry- 
ing and  which  is  particularly  obnoxious 
on  coated  surfaces.  It  must  be  said  again 
that  these  heroic  measures  cannot  have 
the  sanction  of  the  manufacturer  and  he 
will  assume  no  responsibility  therefor. 

Approved  Methods  Apply  Generally 

The  cleaning  methods  described  herein 
are  based  on  long  experience  and  consti- 
tute the  best  techniques  for  the  care  of 
lenses.  No  distinction  need  be  made  be- 
tween the  present-day  coated  lenses  and 
those  few  without  anti-reflection  films 
still  in  service. 

Some  of  the  very  early  lenses  had  an 
extremely  soft  coating  which  would  bear 
no  cleaning,  rubbing  off  easily  with  a 
handkerchief:  these  were  coated  princi- 
pally on  the  interior  surfaces  which  were 
safe  from  damage.  The  coatings  now  ap- 


The  Mechanism  of  Hearing 

OST  people  are  perfectly  content 
1  with  the  knowledge  that  they  can 
hear  the  myriad  and  diverse  sounds  which 
go  to  make  up  a  sound  pattern  which 
impinges  upon  their  consciousness,  but 
very  few  know  or  seem  to  care  much 
about  the  manner  in  which  this  process 
is  accomplished  nor  about  the  remark- 
able human  mechanism  which  permits 
auditory  perception — the  ear. 

A  schematic  cross-section  of  the  human 
ear — and,  as  is  customary,  a  distinction 
is  made  between  the  external,  middle  and 
internal  ear — is  shown  in  Fig.  1.  The 
auditory  organ  proper  is  the  inner  ear, 
more  specifically  the  cochlea,  a  canal  of 
helical  form  embedded  in  the  petrous 
part  of  the  temporal  bone. 

Midway  across  this  canal  is  a  thin 
membrane,  the  so-called  basilar  mem- 
brane, along  which  the  end  organs  of  the 
auditory  nerve  terminate.  The  two  canal 
halves  thus  formed  are  filled  with  liquid. 
They  are  interconnected  at  the  far  end 
of  the  cochlea  by  a  small  aperture,  the 
helicotrema. 

In  Fig.  1  the  cochlea  is  shown  unfurled 
for  clarity,  and  for  simplicity  no  refer- 
ence is  made  to  the  cochlear  duct  and 
associated  organs. 

Transmission,  Pressure  Equalization 

At  the  other  end  of  the  cochlea  there 
are  two  apertures,  one  on ,  each  side  of 
the  basilar  membrane.  The  lowermost, 
the  round  window,  is  closed  by  a  mem- 
brane, whereas  the  other,  the  oval  win- 
dow, accommodates  the  footplate  of  the 
stirrup,  the  final  link  in  the  ossicular 
chain. 

This  chain,  consisting  of  hammer, 
anvil  and  stirrup,  transmits  vibrations  ol 
the  tympanic  membrane  to  the  liquid 
filling  the  cochlea.  The  Eustachian  tube 
provides  equalization  of  steady  pressure 
between  the  two  sides  of  the  ear  drum. 
The    vestibular    apparatus,    also    shown 


schematically  in  Fig.  1,  acts  as  the  organ 
of  equilibrium  by  utilizing  the  three  semi- 
circular canals  which  are  oriented  in 
three  approximately  orthogonal  planes. 
When  the  ear  is  exposed  to  sound  of  a 
given  frequency,  the  sound  pressure  in 
the  auditory  canal  activates  the  eardrum 
whose  vibrations  are  transmitted  through 
the  ossicles  to  the  cochlea.  Wave  mo- 
tion is  set  up  in  the  liquid  of  the  coch- 
lea in  such  a  way  that  the  deflections  on 
the  basilar  membrane  are  localized  in  a 
certain  area. 

Effect  of  Increased  Stimulus 

For  higher  frequency  sound  the  area 
of  maximum  deflection  on  the  basilar 
membrane  is  shifted  towards  the  oval 
window  and  different  end  organs  of  the 
auditory  nerve  are  stimulated.  As  the 
magnitude  of  the  stimulus  is  increased, 
the  deflections  of  the  basilar  membrane 
increase  in  magnitude  and  the  stimula- 
tion of  the  nerve  endings  is  increased 
correspondingly. 

The  functions  of  the  outer  ear,  consist- 
ing of  the  pinna  and  the  auditory  canal 
and  terminated  by  the  eardrum,  is  to 
serve  as  a  transducer  and  pressure  am- 
plifier interposed  between  an  external 
sound  field  and  the  delicate  and  small 
structures  of  the  middle  and  inner  ear. 
The  magnitude  of  the  stimulus  acting  on 
the  auditory  apparatus  can  be  quantita- 
tively evaluated  by  a  measurement  of 
the  sound  pressure  at  some  convenient 
point  in  the  auditory  canal. 

The  combination  of  precise  physiologi- 
cal knowledge  and  expert. application  of 
modern  test  instruments  enables  com- 
munications experts  such  as  those  in 
Bell  Telephone  Laboratories  to  accu- 
rately appraise  every  speech  level  from 
that  of  a  whisper  to  ear-shattering  tonal 
sonorities.  Thus  is  the  communications 
art  advanced. 


FIG.    1. 


Schemctic    cross-section    through    the 
human    ear. 


Silver  Ink  Electronics 

How  would  you  solve  the  very  dainty  task 
of  providing  an  intricate  wiring  system  for 
a  novelty  radio  set  the  size  of  a  match  box? 

It  looks  like  a  problem  which  would  defy 
a  Swiss  watchmaker.  The  solution  is 
simple:  "draw"  the  "wires"  on  a  piece  of 
paper  or  thin  cardboard.  This,  literally,  is 
done,  using  a  silver  solution  as  ink.  Of  all 
metals,  silver  is  the  best  conductor  of  elec- 
tricity and  offers  the  least  resistance  to  its 
passage. 

Silvered  lines  on  paper  carry  the  intricate 
electric  impulses  which  tiny  tubes  "trans- 
late" for  your  ear  into  a  report  on  a  cham- 
pionship fight  or  a  Carnegie  Hall  concert. 


plied  are  made  of  sturdier  stuff  and,  ex- 
cept for  their  thinness,  can  be  handled 
in  much  the  same  manner  as  the  under- 
lying glass  surface.  Both  require  finesse 
in  handling  for  maximum  performance. 
It  is  hoped  that  these  few  notes  will 


aid  in  keeping  »your  lenses  brilliant  for 
the  life  of  the  equipment  on  which  they 
are  used,  a  goal  toward  which  the  manu- 
facturer has  struggled  long  and  hard. 
Potentially  they  can;  treated  properly 
they  will. 


10 


INTERNATIONAL  PROJECTIONIST 


February  1949 


Maker  of  dreams 


•  To  make  dreams  like  this  con- 
vincing ...  to  show  them  with  the 
smoothness  that  brings  life  and 
reality  .  .  .  that  is  the  job  of  the 
optical- effects  man. 

Yet  it  is  only  one  of  his  many 
contributions  to  modern  pictures. 
By  his  skill  with  the  optical  printer 
.  .  .  his  production  of  fades  and 
wipes,  of  dissolves  and  laps  ...  he 


plays  an  important  part  in  giving 
American  movies  their  high  stand- 
ard of  technical  excellence. 

If  the  optical-effects  man  is  to 
play  this  part  to  the  full,  he  must 
use  dependable  film  of  superior 
quality.  That's  why  he  usually  pre- 
fers to  work  with  the  large  and 
well-known  family  of  Eastman 
motion  picture  films. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,     N.    Y. 

J.    E.    BRULATOUR,    INC.,    DISTRIBUTORS 
FORT    LEE    •    CHICAGO    •    HOLLYWOOD 


INTERNATIONAL  PROJECTIONIST 


February  1949 


11 


Photoelectric 
Cell 


Speak 


eaker 


Circuit  1      Circuit  2     Circuit  3    Circuit  4 


j      Circuit  5 


1st  sta£e    2fi<l  stag'e    3rd  staije    Power 
voltage       voltaee         voltaije    amplification 
amplification     ampl.  ampl.  stage 


Voltage  Amplifier 
FIG.  1.    Representation  of  an  amplifier  cascade 


.Power 
Amplifier 


+  ^ 


Inductor 


\ 

Fluctuating  D.C.  — r- 

(D.C.  +  A.C.)  I 


-'TOTOR^ 


Capacitor 


J\ 


-o  + 


D.C. 


A.C. 


FIG.  2.    Filter  circuit  for  separating  the  two  components  of  fluctuat- 
ing direct  current. 


A  COMPLETE  amplifier  consists  of 
several  circuits  coupled  in  such  a 
way  that  power  may  be  transferred  from 
one  circuit  to  another  without  permitting 
the  electrons  flowing  in  one  circuit  to 
pass  into  another  circuit.  Omitting  all 
power-supplying  units  for  the  sake  of 
simplicity,  a  sound  motion  picture  ampli- 
fier is  arranged  in  cascade  as  in  Fig.  1. 

It  will  be  seen  that  there  are  five 
separate,  yet  interdependent,  circuits 
involved  in  this  particular  hook-up.  It 
will  also  be  seen  that  there  are  four 
stages  of  amplification,  the  first  three 
being  voltage,  or  "gain,"  stages,  and  the 
fourth  being  the  power,  or  output,  stage. 
There  is  no  fixed  number  of  stages  in  an 
amplifier,  however;  but  the  greater  their 
number,  as  a  general  rule,  the  greater 
the  overall  amplification. 

Voltage  and  Power  Amplifiers 

The  distinction  between  voltage  ampli- 
fiers and  power  amplifiers  is  clear.  Con- 
sider the  power  amplifier  first.  The 
output  of  this  amplifier  is  connected  to 
the  speakers,  and  speakers  are  power- 
operated  devices.  Power  is  measured  in 
watts,  and  watts  represent  the  mathe- 
matical product  of  volts,  amperes,  and 
power  factor.  Accordingly,  the  tubes  of 
the  power  stage  must  handle  high  values 
of  current  (amperes) .  But  in  order  to 
perform  this  function  the  signal  (sound 
current)  must  be  applied  to  their  grids 
at  a  wide  voltage  "swing,"  or  amplitude. 
It  is  the  purpose  of  the  voltage  amplifier 
to  increase  the  voltage  variations  to  a 
degree  sufficient  to  work  the  power 
amplifier. 

Not  considering  the  widely  different 
"amplification  factors"  of  the  different 
types  of  tubes,  we  see  that  several  stages 
of  voltage  amplification  will  permit  us 
to  use  more  powerful  tubes  in  the  power 
amplifier  than  would  be  the  case  if  we 
had  only  one  voltage  stage.  Indeed, 
sufficient  voltage  amplification  makes  it 
possible  to  connect  two  large  power 
stages  in  parallel  or  in  push-pull  and 
thus  obtain  sufficient  volume  to  fill  the 
biggest  auditorium. 

To  sum  up:  the  power  amplifier  pro- 
vides the  sound  power  that  drives  the 
speakers,  and  the  voltage  amplifier  pro- 


vides the  signal  voltage  to  operate  the 
power   amplifier. 

Current  Components 

In  order  to  comprehend  fully  the  action 
of  amplifier  stages  we  must  investigate 
the  operation  of  electron  tubes,  for  the 
process  of  amplification  takes  place  in- 
side them.  An  exhaustive  discussion  of 
tubes  must  be  deferred;  so  for  the  present 


Sound 

System 

Components 


IV.     Power   Transfer   in    Circuits 

By  ROBERTA.  MITCHELL 


we  shall  view  the  amplifier  tube  more 
broadly  as  a  valve  in  which  a  strong  d-c 
is  controlled  by  a  weaker  d-c,  the  fluc- 
tuations of  the  latter  being  reproduced 
on  a  greatly  enlarged  scale  in  the  stronger 
current. 

The  important  point  to  grasp  is  this: 
it  is  the  fluctuations,  not  the  d-c  itself, 
which  constitute  the  signal — the  electrical 
equivalent  of  sound.  The  d-c  is  necessary 
for  the  operation  of  the  tube,  but  only 
its  "waverings"  are  passed  along  from 
stage  to  stage  and  built  up  to  a  strength 
sufficient  to  drive  the  speakers. 

We  may  take  the  expression  "fluctu- 
ating d-c"  at  its  face  value,  but  a  little 
thought  will  bring  us  to  another  way  of 
looking  at  it:  namely,  that  such  a  "direct" 
current  possesses  to  some  degree  the 
properties  of  a-c.  The  "fluctuating"  part 
of  it  (a-c  component)  is  able  to  pass 
through  condensers  and  induce  currents 
in  chokes  and  transformers.     The  non- 


varying  part  (d-c  component)  is  exactly 
the  same  as  any  well-behaved  d-c :  it  will 
not  pass  through  condensers  or  induce 
secondary  currents  in  inductances. 

The  differences  of  the  two  components 
of  a  pulsating  d-c  provide  methods  of 
separating  them  and  making  them  flow 
in  different  circuits.  Fig.  2  shows  an 
elementary  filter  circuit  designed  to  do 
this  job. 

In  Fig.  2  the  fluctuating  d-c  input  is 
at  the  left.  The  polarity  of  the  input 
connections  is  not  important,  but  in 
deference  to  long-established  convention 
the  negative  lead  is  connected  to  the 
ground  wire  that  runs  clear  through  the 
apparatus.  This  wire  is  drawn  blacker 
than  the  others  in  the  diagram.  In  an 
actual  apparatus  this  "floating  ground" 
should  be  connected  to  the  metal  case 
by  means  of  a  short  length  of  heavy 
wire. 

Tracing  through  the  circuit  we  find 
an  inductance  (choke  coil  having  an 
iron  core)  in  series  with  the  input.  An 
inductance  opposes  a-c  by  its  reactance, 
but,  if  of  the  correct  type,  it  offers  rela- 
tively little  resistance  to  the  flow  of 
direct  current.  But  the  a-c  component 
finds  an  easy  path  through  the  capacitor, 
which  completely  blocks  the  d-c  com- 
ponent. In  this  way  the  two  components 
are  separated  and  diverted  into  different 
channels. 

In  Fig.  3  the  pulsating  d-c  is  fed  into 
the  primary  of  a  transformer.  The  a-c 
component  induces  a-c  in  the  secondary 
winding,  while  the  d-c  component  only 
flows  through  the  primary  without  trans- 
ferring any  power  to  the  secondary. 

This  is  a  very  practical  set-up  for 
obtaining  the  a-c  component  free  from 
d-c,  but  when  the  a-c  component  is  small 
in  comparison  with  the  d-c  component, 
the  primary  of  the  transformer  may  be 


Transfo: 


Fluctuating  D.C. 
(d.c.+  A.C.) 


\ 
A.C. 


FIG.    3.     Circuit    for   separating    an    a-c   com- 
ponent. 


12 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


>ass  condenser 


Type  45 
Power  tube 

=  1,700  a) 


Output 
Transformer 


Resistor 


FIG.   4.    Separating   a-c   when   the   d-c   component   is   too   large   to   be 
safely  carried   by  the  transformer  primary. 


■12  ft 


Speaker 

/ 


12  n, 


FIG.  6.    Impedance  match  in  power  amplifier  plate  circuit  and  in  speaker 

circuit. 


burned  up   by  the  heavy  direct  current. 

There  are  two  ways  of  circumventing 
this  difficulty.  We  may  substitute  a  trans- 
former of  very  great  current-carrying 
capacity;  but  large  transformers  are  ex- 
pensive. As  an  alternative  we  may  inter- 
pose a  capacitor  in  the  primary  circuit. 
The  capacitor  will  by-pass  the  a-c  and 
keep  the  harmful  d-c  out  of  the  trans- 
former. But  here  again  we  find  our- 
selves in  difficulties,  for  amplifier  plate 
circuits  must  carry  rather  high  d-c  volt- 
ages, and  the  capacitor  prevents  the  d-c 
from  flowing. 

This  problem  is  solved  by  using  a 
resistor  shunt  (Fig.  4)  the  purpose  of 
which  is  to  pass  d-c  while  the  condenser 
passes  the  a-c.  The  efficiency  of  this 
hook-up  is  certainly  not  of  the  highest 
order — a-c  is  drained  off  through  the 
resistor  and  wasted — but  this  method 
has  been  used  in  cheaply  built  amplifiers 
with   fairly   good   results. , 

The  actual  design  of  filter  and  a-c 
transfer  circuits  such  as  these  calls  for. 
consideration  of  the  strength  of  the  d-c 
component,  the  maximum  amplitude  of 
the  a-c  component,  the  frequency  or  fre- 
quencies of  the  modulating  a-c  (30  cycles 
to  9,000  cycles  in  sound  current),  and 
the  impedance  of  the  source.  We  shall 
see  shortly  that  the  impedance  of  both 
"source"  and  "load"  is  un  extremely 
important  factor  in  amplifier  circuits. 

So  far  we  have  considered  only  meth- 
ods of  separating  the  two  components  of 
pulsating  d-c.  One  of  these  methods — 
that  of  using  a  transformer  to  obtain  the 
a-c  component  free  from  d-c — serves  as 
a  very  simple  means  of  transferring 
sound  current  (the  a-c  component)  from 
one  amplifier  stage  to  another.  There 
are  two  other  widely  used  methods  of 
circuit  coupling,  but  the  purpose  of  each 
is  to  transfer  pulsating  d-c  to  a  load 
resistance  or  impedance,  and  to  apply 
the  separated  a-c  component  to  the  grid 
of  an  amplifying  tube  or  to  the  voice 
coil  of  a  speaker. 

Action  of  the  Tube 

Figure  5  represents  the  plate  circuit 
of  a  rudimentary  amplifier  stage.  This 
may  be  either  a  voltage  stage  or  a  power 
stage;  we  cannot  tell  by  looking  at  the 
picture.     The  tube  is  represented  by  a 


circle  (the  glass  envelope)  in  which  are 
located  the  plate,  the  electron-emitting 
cathode,  and,  interposed  between  them, 
the  grid. 

When  the  cathode  is  heated,  as  by  a 
hot  filament,  current  from  the  "B"  bat- 
tery will  flow  through  the  vacuum  from 
the  cathode  to  the  plate,  thence  around 
the  circuit  through  the  load  and  back 
to  the  battery.  Note  that  the  negative 
terminal  of  the  battery  is  connected  to 


Plat 


Catkode 


Load 
mpeaai 


"JB"  Battery 

FIG.  5.    Plate  resistance  and   load   impedance. 

the  cathode.  If  the  connections  are  re- 
versed, the  tube   will   not  work. 

Now,  the  electrons  emitted  by  the  hot 
cathode  and  drawn  across  the  vacuum 
to  the  positively-charged  plate  are  re- 
quired to  pass  through  the  mesh  of  the 
grid,  which  is  usually  made  of  wire  gauze. 
The  varying  negative  charge  placed  on 
the  grid  by  the  source  of  sound  current 
or  a  previous  amplifier  stage  regulates 
the  current-flow  from  the  cathode  to  the 
plate. 

When  the  grid  becomes  strongly  nega- 
tive, the  negatively-charged  electrons  are 
repelled  and  only  a  few  of  them  manage 
to  pass  through  to  the  plate.  When  the 
grid  becomes  less  negative,  more  elec- 
trons are  allowed  to  get  by  and  a  heavier 
plate  current  results.    The  plate  current 


therefore  varies  according  to  the  fluctu- 
ating charge  of  the  grid. 

The  grid  is  very  much  like  a  traffic 
light  controlling  a  stream  of  cars  (elec- 
trons). A  low  negative  charge  is  the 
green  light,  and  a  high  negative  charge 
is  the  red  light.  When  the  red  light  is 
on,  only  a  few  very  daring  individuals 
dash  through.  It  might  seem  as  though 
a  positive  charge  on  the  grid  would  be 
the  best  sort  of  "green  light"  for  the 
electrons.  Actually,  a  positive  swing  in- 
troduces serious  distortion  into  the  sound. 

In  Class  A  amplifiers  the  grid  does 
not  even  swing  to  neutral  (no  charge), 
for  that  would  also  distort  the  sound. 
Class  B  and  C  amplifiers  have  important 
applications  in  radio  work;  but  in  motion 
picture  projection  we  are  interested  only 
in  high-fidelity  Class  A  amplifiers,  those 
in  which  the  tube  grids  are  always  more 
or  less  negatively  charged. 

Source  and  Load  Impedance 

The  purpose  of  the  plate  circuit  (Fig. 
5)  is  to  transfer  power  to  the  load  im- 
pedance. The  load  impedance  may  be  a 
plate  resistor,  or  it  may  be  a  load  in- 
ductance or  the  primary  of  a  transformer, 
depending  on  the  method  of  coupling. 
Just  for  a  moment  let  us  consider  it  to 
be  a  pure  resistance. 

Suppose  the  resistance  which  the  cur- 
rent encounters  in  passing  through  the 
tube  from  cathode  to  plate  (plate  resist- 
ance, represented  by  rp)  is  10,000  ohms. 
If  we  assume  a  value  of  1000  ohms  for 
the  load  resistance  (R)  the  total  resist- 
ance of  the  circuit  is  11,000  ohms.  If 
the  plate  supply  is  250  volts,  the  current 


+ 

^-1 

I 

PLATE 
VOLTAGE 

PLATE  RESISTANCE 
Ohms 

T 

LOAD   IUPEDAWCE 
Ohms 

PLATE  CTJRRElfT 
llilliamperes 

T 

LOAD  DROP 
Volts 

T 

LOAD  P0TOH 
Watts 

250 

10,000 

1 

25.00 

0.02500 

0.0006250 

250 

10,000 

10 

24.98 

0.2498 

0.006240 

250 

10,000 

100 

24.75 

2.475 

0.06126 

250 

10,000 

1,000 

22.73 

22.73 

0.5167 

250 

10,000 

10,000 

22.50 

225.0 

5.063      ^ 

250 

10,000 

100,000 

2.273 

227.3 

0.5167 

250 

10,000 

1,000,000 

0.2475 

247.5 

0.06126 

TABLE  A.    Voltage  and  power  transfer  with  different  values  of  load  impedance. 


INTERNATIONAL  PROJECTIONIST 


February  1949 


13 


Audio    transformer 
(Voltage  step-up  3:1) 


0.01  p.f 


Output 


y  y   t  t 

B-  B+  C-  C  + 

FIG.  7.    Transformer  coupling. 


100,000  si 


"Open"  primary  ...  and  -with  circuit    change  f 

FIG.  8.    Emergency  hook-up  for  burned-out  transformer  primary. 


flowing  through  the  circuit    (plate  cur- 
rent) is: 


250 


1  = 


=  0.02273  amp. 


rp  +  R        11,000 

The  voltage-drop  across  the  plate  resistor 
in  this  case  is: 

Er  =  IR  =  0.02273  X  1000 

=  22.73  volts. 

Now  this  corresponds  to  a  power  of: 

PE  =  PR  =  (0.02273) 2  X  1000 

=  0.5167  watt. 

Let  us  now  try  other  values  for  the 
plate  resistor  to  find  out  if  some  other 
value  will  give  us  more  power.  The 
results  may  be  tabulated  as  in  Table  A. 

Impedance  Rules 

The  accompanying  table  reveals  that 
(1)  for  a  maximum  transfer  of  power 
the  load  impedance  should  be  equal  to 
the  "source"  impedance  (here  the  plate 
resistance)  ;  and  (2)  for  a  maximum 
drop  of  voltage,  the  load  impedance 
should  be  as  high  as  possible. 

The  second  of  the  two  aforementioned 
"rules"  interests  us  when  we  have  voltage 
amplifiers  under  consideration.  In  actual 
practice  we  must  choose  the  highest  value 
for  the  load  impedance  which  permits  the 
proper  voltage  to  be  applied  to  the  plate 
of  the  tube  from  the  B  battery.  In  a 
power  amplifier  the  load  impedance  is 
ordinarily  the  primary  of  the  output 
transformer.  The  d-c  resistance  of  the 
primary  should  be  low  enough  to  permit 
a  reasonably  large  current  to  flow 
through  the  plate  circuit. 

Strange  as  it  may  seem,  the  first  of  the 
two  aforesaid  impedance  rules  is  usually 


disregarded  in  interstage  coupling.  This 
does  not  mean  that  the  rule  is  not  true. 
If  we  wish  a  maximum  transfer  of  power, 
we  absolutely  must  make  the  load  im- 
pedance equal  to  the  plate  resistance. 
But  it  is  found  that  when  a  tube  is 
operated  with  so  low  a  value  of  load, 
considerable  harmonic  distortion  is  pro- 
duced in  the  sound.  Distortion  must  be 
avoided  at  all  costs ! 

So  we  compromise  a  little  and  make 
the  load  impedance  twice  the  plate  re- 
sistance of  the  tube.  We  lose  a  little 
power  by  so  doing,  but  that  is  a  small 
price  to  pay  for  freedom  from  distorted 
sound.  Further,  if  we  make  the  load 
impedances  about  five  times  the  plate 
resistances  in  the  voltage-amplification 
stages,  we  will  stand  a  better  chance  of 
keeping  second-harmonic  distortion  under 
the  5%  limit.o  Carefully  conducted  tests 
have  proved  that  the  human  ear  cannot 
detect  second-harmonic  distortion  of  5%. 
or  less. 

Second-Harmonic  Distortion 

The  first  harmonic  of  a  tone  is  twice 
the  fundamental  frequency  of  the  tone. 
The  second  harmonic  is  twice  the  fre- 
quency of  the  first  harmonic.  Thus  the 
second  harmonic  of  a  300-cycle  note  is 
1200  cycles.  Practically  all  natural 
sounds  are  rich  in  harmonics — they  pro- 
vide the  distinguishing  tonal  character- 
istics called  quality,  or  timbre — but  we 
must  not  tolerate  an  amplifier  that  intro- 
duces harmonics  not  present  in  the 
original  sound! 

When  an  amplifier  produces  second 
harmonics,  not  only  the  fundamental 
frequency  of  the  original  sound  but  all 
its  natural  harmonics  are  supplied  with 


spurious  second-harmonic  components. 
The  result  is  a  very  harsh  metallic 
quality. 

As  a  general  rule,  then,  we  make  the 
load  impedance  at  least  twice  the  value 
of  the  plate  resistance  of  the  tube.  But 
when  we  come  to  speaker  circuits  we 
adhere  to  the  rule  of  maximum  power 
transfer  and  obey  it  to  the  letter. 

If,  for  example,  the  voice-coil  im- 
pedance of  a  speaker  is  12  ohms,  the 
secondary  winding  of  the  output  trans- 
former should  have  an  impedance  of  12 
ohms.  If  we  replace  the  speaker  with 
another  having  a  very  different  imped- 
ance, we  must  perforce  also  replace  the 
output  transformer  with  one  that  pro- 
vides matched  impedance  to  the  new 
speaker. 

Transformer  Coupling 

Several  examples  of  transformer  coupl- 
ing have  already  been  given.  (See  Figs. 
3.  4,  and  6.)  When  this  type  of  coupling 
occurs  in  a  voltage  stage,  the  output  of 
the  transformer  is  added  to  the  grid-bias 
voltage  of  the  next  tube  for  further  ampli- 
fication. The  details  of  the  grid  circuit 
are  left  for  future  consideration,  hence 
are  omitted  from  Fig.  7. 

Transformers  intended  for  interstage 
coupling  are  called  audio  transformers. 
These  transformers  usually  have  turn- 
ratios  of  3  to  1,  the  primary  being  the 
coil  with  the  fewer  turns.  An  audio 
transformer  is  therefore  a  step-up  trans- 
former, increasing  the  voltage  almost 
three  times.  Due  to  factors  of  winding 
capacitance,  a  higher  turn-ratio  is  con- 
sidered incompatible  with  high  standards 
of  sound  reproduction. 

Transformer  coupling  is  so  simple  and 


>"S* 


S 


500,000^ 


Pri. 


'Open "  secondary  . . .  and  altered  circuit 

FIG.  9.    Emergency  hook-up  for  burned-out  transformer  secondary. 


■mary    anc 
■secondary 
"open  " 


improvised  circuit 


.and--        <mf' 

FIG.    10.     Emergency    hook-up   when    both    primary    and    secondary   of 
transformer   are   open. 


14 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


Load 
inductance 


Output 


Output 


Y  Y  Y  Y 

B-  B+  C-  C+ 

FIG.   11.     Representation    of   impedance   coupling. 


ft  T  Y 

B-  B+  C-  C  + 

FIG.    12.     Representation    of    resistance    coupling. 


efficient  that  it  would  appear  to  commend 
itself  at  once  to  all  builders  of  amplifiers. 
Such,  however,  is  not  the  case. 

First  of  all,  transformers  are  rather 
expensive,  but  what  is  more  impor- 
tant, transformers  introduce  undesirable 
"peaks"  (frequency  distortion)  and  spuri- 
ous frequencies  (harmonic  distortion) 
into  the  sound.  So  in  order  to  keep  the 
distortion  factor  below  5%  we  must  look 
to  other  methods  of  coupling. 

A  few  of  the  first  amplifiers  built  for 
sound  pictures  employed  interstage  trans- 
former coupling  much  too  often.  It  is 
consequently  impossible  to  obtain  sound 
of  acceptable  quality  from  these  old- 
fashioned  equipments.  A  new  speaker 
assembly  accomplishes  little  when  the 
need  is  a  new  amplifier.  Modern  manu- 
facturers avoid  the  use  of  transformers 
as  much  as  possible.  But  some  of  the 
earlier  amplifiers  are  still  in  use,  hence  a 
few  "kinks"  that  will  enable  a  projec- 
tionist to  keep  the  show  running  in  the 
event  of  a  burned-out  audio  transformer. 

Assume  that  tests  indicate  an  open 
.primary.  A  100,000-ohm  resistor  is  con- 
nected across  the  open  primary,  and  the 
terminals  marked  P  and  G  are  connected 
through  a  0.01-microfarad  condenser,  as 
in  Fig.  8.  This  value  of  capacitance  is 
not  "cut  and  dried,"  but  may  be  varied 
within  wide  limits.  In  certain  cases  a 
G.005-microfarad  capacitor  gives  better 
results.  If  possible,  select  a  mica  con- 
denser for  the  "coupling  capacitor." 

When  the  secondary  is  open,  a  500,000- 
ohm  resistor  is  connected  across  the 
secondary  terminals,  and  a  0.01-micro- 
farad capacitor  is  thrown  across  the  P 
and  G  terminals,  as  before  (see  Fig.  9). 
Both  these  emergency  hook-ups  change 
the  transformer  coupling  to  impedance 
coupling.  These  hook-ups  will  work  ex- 
cellently, but  some  volume  will  probably 
be  lost,  necessitating  a  volume  setting 
several  steps  higher  than  normal. 

In  case  both  primary  and  secondary 
of  an  audio  transformer  have  gone  bad, 
we  have  simply  to  combine  the  foregoing 
two  emergency  hook-ups.  Fig.  10  shows 
the  altered  circuit.  These  changes  con- 
vert the  transformer  coupling  to  resist- 


ance coupling,  the  best  type  of  all  when 
high-fidelity  reproduction  is  considered. 
However,  the  volume  will  be  cut  down 
rather  sharply. 

WARNING:  These  emergency  meas- 
ures are  intended  to  correct  defective 
audio  transformers,  and  are  not  suitable 
for  application  to  output  or  speaker- 
matching  transformers. 

Impedance  Coupling 

Impedance  coupling  represents  an  at- 
tempt to  do  away  with  much  of  the  dis- 
tortion inherent  in  transformer  coupling 
and  yet  permit  sources  of  "B"  current 
of  lower  voltage  than  is  possible  with 
risistance  coupling,  soon  to  be  described. 
A  choke  called  a  "load  inductance"  takes 
the  place  of  the  transformer  primary. 
The  a-c  voltage  developed  across  this 
choke  is  transferred  to  the  grid  of  the 
subsequent  tube  through  a  coupling  con- 
denser. This  condenser  (about  0.01  pi) 
keeps  the  large  positive  charge  from  the 
B  battery  off  the  grid  of  the  tube.  The 
voltage-drop  developed  across  the  grid- 
leak  resistor  combines  with  the  negative 
charge  of  the  C  battery  to  give  a  varying 
negative  charge  on  the  grid. 

Resistance  Coupling 

When  the  maximum  degree  of  fidelity 
is  desired  in  the  output  of  an  amplifier, 
resistance  coupling  is  used  throughout 
the  voltage  stages  and  between  the  last 
voltage  stage  and  the  power  stage.  Be- 
cause a  fixed  value  of  resistance  offers 
practically  the  same  impedance  to  all 
frequencies  of  a-c,  the  "response"  of 
resistance-coupled  amplifiers  is  substan- 
tially "flat"  and  free  from  second-har- 
monic distortion.  This  does  not  mean 
that  an  amplifier  employing  this  method 
of  coupling  is  a  priori  perfect,  for  distor- 
tion may  be  caused  by  a  number  of 
factors;  but  a  resistance-coupled  ampli- 
fier of  balanced  design  and  utilizing  de- 
generative feedback  may  reasonably  be 
expected  to  give  top-notch  results  when 
connected  to  a  high-quality  speaker  com- 
bination. 

Figure  12  illustrates  resistance  coup- 
ling. The  close  similarity  of  this  method 
to  impedance  coupling  is  apparent  at  a 


glance.  The  only  difference  is  the  sub- 
stitution of  a  plate  resistor  for  the  load 
inductance. 

The  plate  resistor  is  the  load  to  which 
the  tube  transfers  its  power.  The  value 
of  this  resistor  should  be  two  or  more 
times  the  plate  resistance  of  the  tube. 
If  there  is  any  uncertainty,  the  mistake 
should  be  made  on  the  "large"  side — 
that  is,  the  resistor  should  have  a  higher 
resistance  than  is  absolutely  necessary. 

The  grid-leak  resistor  may  have  a 
resistance  value  of  about  500,000  ohms 
(0.5  megohm).  The  coupling  capacitor 
is  best  about  0.01  pf,  and  it  should  be  a 
mica  condenser  to  avoid  the  danger  of 
slight  "leaks"  which  would  alter  the 
"grid  bias,"  the  delicately  adjusted  nega- 
tive charge  placed  on  the  grid  of  the 
following  tube. 

[The  End] 
'Journal  of  Commerce'  Views  '49  Biz 

Motion  picture  business  will  be  merely 
"terrific"  instead  of  "sensational"  as  in  the 
immediate  postwar  period,  according  to  an 
article  appearing  in  the  Journal  of  Com- 
merce (New  York).  Earnings  during  1949 
are  expected  to  match  those  for  1948,  states 
the  story,  because  of  the  economy  programs 
instituted  of  late  and  through  the  amortiza- 
tion of  expensive  features  made  at  compara- 
tively high  cost. 

The  story  points  out  that  theatre  attend- 
ance has  "apparently  stabilized"  at  from 
12  to  15%  below  the  1947  level,  with  the 
last  months  of  1948  and  the  first  month  of 
this  year  holding  much  promise  for  sus- 
tained patronage. 


Writing  Your  Signature  in  Silver 

How  would  you  sign  your  name  on  glass? 
That's  a  problem  makers  of  radio  and  tele- 
vision tubes  faced.  They  wanted  their  prod- 
ucts "branded"  with  their  trademarks. 

They  found  the  answer:  they  sign  with 
silver — and  it's  as  simple  as  rubber-stamping. 
The  "ink"  is  silver  oxide  mixed  with  bis- 
muth and  ' glycerine.  After  stamping,  the 
tube  is  heated.  The  silver  oxide  becomes 
pure  silver — and  the  maker's  signature  is 
there  to  stay.  Thus  there  was  chalked  up 
another  score  for  silver,  the  most  versatile 
industrial  metal. 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


15 


The   New  M-G-M  Stereopticon 

By  MERLE  CHAMBERLIN 

Chief  Projectionist,  Metro-Goldwyn-Mayer  Studios 


BEFORE  we  proceed  with  a  description 
of  the  new  M-G-M  stereopticon,  it 
might  be  well  to  explain  why  we  need 
and  how  we  use  this  unit  of  projection 
equipment.  As  pointed  out  previously  in 
IP,  background  projection  is  a  vitally  im- 
portant function  of  the  projection  depart- 
ment in  a  motion  picture  studio.  This 
specialized  work  involves  the  projection 
of  both  motion  pictures  and  slides,  the 
latter  being  used  on  sets  where  the  back- 
ground requires  no  animation  or  move- 
ment. Due  to  variations  in  set  dimen- 
sions, the  projected  width  will  range  from 
2  to  40  feet. 

Up  to  the  present  time  we  did  this 
work  with  an  assembled  machine.  This 
equipment  being  strictly  an  assembly 
job,  numerous  additions  and  deletions 
were  made  as  the  occasion  arose.  This 
unit  was  never  too  successful,  but  it  did 
get  us  by. 

Experience  having  taught  us  what  was 
required,  we  proceeded  to  design  a  ma- 
chine that  would  successfully  meet  the 
manifold  requirements  as  a  stereopticon. 
This  equipment  would  be  required  to 
project  any  stationary  glass  or  film  pic- 
ture from  2x2  transparencies  to  full 
size  slides.  The  amperage  range  should 
be  from  90  to  250  to  compensate  for 
varying  densities  in  original  material. 
Slides  must  be  left  on  for  periods  up  to 
an  hour  without  endangering  either  glass 
or  emulsions.  The  machine  also  had  to 
be  flexible  from  the  standpoint  of  a  maxi- 
mum panning  and  tilting  range. 

Stereo  Requirements  Satisfied 

We  now  have  a  unit  that  meets  all  the 
aforementioned  requirements.  Fig.  1 
shows  the  complete  machine;  Fig.  2 
shows  the  inside   of  the  working  head. 


This  machine  has  been  put  through  every 
kind  of  test  we  could  devise  and  it  has 
responded  efficiently.    Consider  Fig.  2. 

Any  size  slide  may  be  mounted  in  the 
holder,  A.  The  slide  is  suspended  instead 
of  being  clamped,  to  allow  for  heat  ex- 
pansion and  contraction  of  the  basic  slide 
material.  Amperage  range  is  taken  care 
of  by  an  adjustable  grid  carried  with  the 
machine.  Slides  can  be  left  on  for  any 
period  of  time,  due  to  the  cooling  system 
used. 

First,  a  large  amount  of  the  heat  is 
dissipated  by  passing  the  light  through 
a  water  cell,  B.  The  slide-holding  area  is 
cooled  by  two  air  ducts,  C,  which  are 
fed  by  the  blower  D.  The  speed  of  this 
blower  is  governed  by  an  adjustable 
rheostat. 

In  cases  of  extreme  amperage  and/or 
slide  density,  the  shutter  E  is  used.  This 
projector  shutter  is  synchronized  with 
the  camera  shutter  by  means  of  interlock- 
ing motors  F  controlled  by  a  distributor 
operated  by  the  projectionist.  Manual 
control  of  this  shutter  is  by  means  of 
the  knob  G  on  the  front  of  the  head. 

Dual  Lens  Mount  Control 

The  lens  mount  H  is  flexible  so  as  to 
permit  the  use  of  any  diameter  lens. 
Movement  of  this  lens  mount  is  by  a 
motor  /  which  is  controlled  by  the  pro- 
jectionist, but  control  can  be  switched  to 
the  cameraman,  thereby  permitting  focus 


FIG.   1.    Complete  assembly  of   M-G-M  stere- 
opticon  mounted   on   a   Simplex  LLI   base. 

of  the  picture  by  the  viewer.  This  con- 
trol is  by  switches  /  mounted  on  the  head. 

The  panel  K  includes  necessary  d-c 
and  3-phase  a-c  remote  switches.  The 
base  is  the  standard  Simplex  LLI  heavy 
duty  type,  with  the  mounting  plate  modi- 
fied for  this  specific  piece  of  equipment. 
The  lamp  is  the  standard  Peerless  Hi- 
Candescent. 

This  machine  was  designed  and  fab- 
ricated by  projectionist  members  of  Local 
165  and  Cine  Technician  members  of 
Local  789,  I  A,  working  at  the  M-G-M 
studio.  We  admit  that  our  stereo  is  a 
far  cry  from  those  magic  lantern  jobs  of 
days  gone  by,  but  we  feel  that  this  ma- 
chine is  one  of  the  most  advanced  and 
practical  pieces  of  equipment  of  this 
type  in  the  industry. 


Addendum:   SMPE   64th    Convention   Papers   Abstracts 


FIG.  2.    Interior  of  M-G-M  stereopticon. 


NOW  available  are  the  balance  of  the 
abstracts  of  papers  presented  before 
the  last,  64th,  Convention  of  the  Society 
of  Motion  Picture  Engineers.  Abstracts 
of  those  papers  of  especial  interest  to  pro- 
jectionists are  appended  hereto: 

WHAT    IS    HIGH-SPEED    PHOTOGRAPHY? 

Maynard    L.    Sandell 

Eastman  Kodak  Company 

High-speed  photographs  are  defined  as 
those  (a)  in  still  photography,  having  ex- 
posures in  excess  of  1/1000  second  and  (b) 
in  motion  picture  photography,  having  ex- 
posures in  excess  of  1/250  of  a  second.  The 
history  of  photography  of  this  type  is  briefly 
discussed. 

ELECTRICAL    FLASH    PHOTOGRAPHY 

Harold    E.    Edgerron 
Massachusetts   Institute  of   Technology 

The  circuits  and  components  now  in  use 
in  the  production  of  electronically-controlled 
flashes  for  photography  are  described,  to- 
gether   with    a    method    of    measuring    the 


integrated  incident  light  from  flash  sources 
and  a  meter  for  making  the  measurement. 
The  theory  and  design  of  light  production 
and  methods  of  calculating  exposure,  es- 
pecially for  color  materials,  is  discussed. 

NEW  HIGH-SPEED  STROBOSCOPE  FOR  HIGH- 
SPEED   MOTION    PICTURES 
K.    J.   Germeshausen 
Massachusetts  Institute  of   Technology 

A  high-speed  stroboscopic  source  of  light 
has  been  developed  which  will  minimize  the 
lack  of  definition  cited  as  a  major  disad- 
vantage of  optical  type  high-speed  cameras. 
The  advantages  of  this  type  of  light  source 
over  others  are  discussed  and  examples 
given  of  the  benefits  accruing  from  an 
intermittent  source  of  light. 

LAMPS   FOR   HIGH-SPEED   PHOTOGRAPHY 

R.   E.    Fornham 

General  Electric  Company 

This  paper  discusses  the  general  require- 
ments of  light  sources  for  high-speed  motion 

(Continued  on  page  27) 


16 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


IT  APPEARS  that  to  reproduce  color 
one  would  have  first  of  all  to  know  all 

about  color.  However,  just  as  in  black- 
and-white  photography,  the  applied  art 
seems  to  have  flourished  remarkably 
and  developed  its  practical  methods  to- 
ward more  perfect  results  without  too 
much  worry  about  the  many  question 
marks,  which  still  make  those  concerned 
with  photo-reproductive  theory  wonder 
about  the  true  nature  of  its  fundamentals. 

The  fact  that  we  resort  to  at  least 
three  different  theories  explaining  the 
phenomena  of  light — the  electro-mag- 
netic, the  corpuscular  and  the  quantum 
theories,  instead  of  a  single  one — is  suffi- 
cient proof  that  we  are  still  groping  for 
basic  truths. 

The  science  of  color  presents  not  only 
an  alarming  number  of  difficult  ques- 
tions relating  to  pure  physics.  A  large 
part  of  what  we  know  of  color  reactions 
defies  explanation  through  an  approach 
by  physics.  It  can  only  be  properly 
understood,  described  and  classified  as 
psycho-physical  and  as  psychological 
phenomena,  or  as  color  sensations. 

Color  Photography  Basis 

The  recognition  of  the  fact  that  by  mix- 
ing three  primary  colors — red,  green  and 
blue-violet — in  different  proportions  any 
other  color  can  be  obtained  or  matched 
had  slowly  grown  out  of  the  practical 
experience  and  observations  of  early 
painters.  It  became  the  lasting  contri- 
bution of  Thomas  Young  to  furnish  ac- 
curate experimental  proof  and  formulate 
it  into  a  basic  law,  which  in  consequence 
seemed  to  require  the  assumption  that 
the  human  eye  must  be  equipped  with 
three  receptors,  each  sensitive  to  only 
one  of  the  primary  colors.  This  theory, 
although  physiologically  not  at  all 
proven,  has  furnished  the  foundation 
upon  which  color  photography  has  been 
begun  and  developed. 

The  additive  primaries,  of  which  little 
can  be  said  as  to  their  physical  properties 
since  color  itself  is  not  a  substance  but 
a  sensation,  have  certain  characteristics 
which  distinguish  them  from  other  colors. 
One  is  that  none  of  them  can  be  matched 
by  any  two  other  colors.  A  further  ob- 
servation is  that  all  three  primaries,  when 
mixed  additively,  result  in  the  sensation 
of  white. 

Three  Complementary  Primaries 

From  this  follows  that  the  additive 
mixture  of  two  of  the  primaries  is,  in 
each  instance,  complementary  to  the 
third  primary,  since  we  also  know  that 
complementary  colors  are  colors  which 
when  additively  mixed  will  result  in 
white. 

The  colors  of  the  three  complementary 
or  secondary  primaries  which  we  use  in 

t  American   Cinematographer  for  Jan.  1948. 


synthesizing  the  color  print  when  prac- 
ticing the  subtractive  process  are:  cyan, 
complementary  to  primary  red ;  magenta, 
complementary  to  primary  green;  and 
yellow,  complementary  to  primary  blue- 
violet. 

It  follows,  therefore,  that  cyan  must 
be  the  same  as  the  additive  mixture  of 
primary  green  and  blue-violet,  which,  as 
was  stated,  is  also  complementary  to  red. 
This  explains  the  often  used  other  name 
for  cyan,  which  is  minus  red.  Similarly, 
it  follows  that  magenta  must  be  the 
same  as  the  additive  mixture  of  primary 
blue-violet  and  red  and  is,  therefore, 
called  minus  green.  Last,  yellow  must 
be  equal  to  the  additive  mixture  of  red 


In  the  additive  process  of  color  re- 
production the  individual  print  from 
each  of  the  color  separation  negatives 
is  illuminated  in  projection  by  light 
identical  in  color  composition  to  that 
transmitted  by  the  corresponding  pri- 
mary exposing  filter.  The  print  itself  is 
black-and-white,  and  the  different  dens- 
ities merely  modulate  the  amount  of 
colored  light  passing  through  the  silver 
image.  This  modulated  light  from  each 
print  is  superimposed  and  additively 
mixed  on  the  screen.  Black  is,  therefore, 
obtained  where  all  three  colored  light 
sources  are  prevented  from  reaching  the 
screen  by  heavy,  opaque  silver  deposits. 
White    is    obtained    when    all    all   three 


Color:  Its  Complex  Structure 


By  DR.  HERBERT  MEYER 

Motion   Picture  Research  Council 


and    green    and    is    accordingly    named 
minus  blue   (blue-violet) . 

The  two  fundamental  processes  used 
for  photographic  color  reproduction  are 
known  as  additive  and  subtractive  meth- 
ods. In  making  the  negative  exposure,  in 
order  to  obtain  color  separation  nega- 
tives, identical  primary  color  filters  can 
be  used  for  either  method.  These  filters 
are  practically  standardized  as  red  filter 
A  (dominant  wave-length  610  millimi- 
crons) ;  green  filter  B  (dominant  wave- 
length 546  millimicrons)  ;  and  blue  filter 
C-5  (dominant  wave-length  649  milli- 
microns) . 

The  eye  can  not  distinguish  the  indi- 
vidual components  in  a  color  mixture, 
which  is  rather  advantageous  in  color 
reproduction  since  it  makes  it  permissible 
to  use  filters  or  dyes  which  transmit  rela- 
tively wide  or  widely  separated  bands, 
instead  of  one  narrow-banded,  mono- 
chromatic hue.  The  dominant  wave- 
length of  a  filter,  therefore,  represents 
the  mean  hue  transmitted  by  the  filter. 

The  length  of  a  single  wave  of  vis- 
ible radiation  is  exceedingly  small,  so 
that  to  avoid  the  difficulty  or  awkward- 
ness of  thinking  and  speaking  in  such 
small  figures,  wave-length  is  customarily 
expressed  in  millimicrons  or  in  Ang- 
strom units. 

1  millimicron  =  .000001  mm 
1  Angstrom  unit  =  .0000001  mm 

The  visible  range  of  the  spectrum 
reaches  accordingly  from: 

400  to  700  millimicrons 
4,000  to  7,000  Angstrom  units 


colored  light  bundles  reach  the  screen 
in  equal  intensities. 

In  the  subtractive  process  of  color  re- 
production the  individual  prints  (or 
print  layers)  of  each  of  the  color  sepa- 
ration negatives  are  dyed  in  their  respec- 
tive complementary  colors  and  superim- 
posed upon  each  other  prior  to  projec- 
tion. This  combined,  multiple-dyed  print 
is  then  projected  on  the  screen  with 
white  light. 

Since,  in  this  instance,  each  dyed  com- 
ponent absorbs  its  complementary  part 
of  the  all-color  mixture  of  the  white 
light,  it  follows  that  this  type  of  projec- 
tion is  subtractive,  which  means  that 
where  no  dye  interferes  with  the  pro- 
jected white  light,  the  screen  reflects 
white;  where  all  three  dyes  interfere  in 
equivalent  densities,  the  screen  will  be 
black,  since  all  components  of  the  white 
light  are  absorbed  and  prevented  from 
being  transmitted  through  the  film  on 
to  the  screen. 

Measurable,  Reproducible  Factors 

The  field  of  measuring  colors  is  called 
"colorimetry".  One  of  its  more  recent 
endeavors  concerns  the  systematic  de- 
termination and  classification  of  colors 
on  the  basis  of  measurable  and  repro- 
ducible units  or  factors.  It  establishes 
for  this  purpose  numerical  values  for 
three  specific  attributes  of  colors  which 
determine  qualitatively  and  quantita- 
tively their  relations  and  differences. 
These  attributes  are,  in  the  order  of  their 

(Continued  on  page  26) 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


17 


Stability  vs.  Chaos  in  Tv. 

A  summary  of  what's  right  and  what's  wrong  about  the  video  art  by  an 
acknowledged  expert.  No  stranger  herein,  the  author  is  an  honorary 
member  of  I A  Local  306  and  also  of  the  25-30  Club  of  New  York  City. 

By  DR.  ALFRED  N.  GOLDSMITH 


"HERE  are  numerous  occasions,  these 
days,  when  any  impartial  observer  of 
television  events  has  the  impression  that 
all  is  hurry  and  scurry  with  but  little 
definite  direction.  One  is  reminded  of 
Stephen  Leacock's  description  of  the 
knight  in  the  Middle  Ages  who  jumped 
on  his  horse  and  galloped  off  wildly  in  all 
directions.  It  is  always  difficult — and 
sometimes  impossible — to  reach  any  de- 
sired destination  in  that  inappropriate 
fashion. 

Television  is  an  inspiring  field,  and 
many  people,  naturally  enthusiastic,  get 
more  or  less  novel  ideas  concerning  tech- 
niques, programming,  regulatory,  engi- 
neering or  other  matters.  Some  of  these 
ideas  are  actually  new;  others  are  merely 
rehashed  versions  of  unsuccessful  and 
discarded  thoughts  of  the  past. 

Open  Sesame  for  Ideas 

It  would  be  reasonable  to  expect  that 
all  proposed  ideas  receive  some  attention 
and  analysis.  Growing  fields  like  tele- 
vision should  never  close  their  doors  to 
the  pioneer  and  innovator.  On  the  other 
hand,  this  does  not  in  the  least  imply 
that  every  new  idea  must  be  instantly 
adopted  or  caused  to  block  current  prog- 
ress. It  is  possible  to  be  so  open-minded 
that  one  merely  becomes  empty-minded. 

Many  individuals  who  have  little  be- 
yond enthusiasm  receive  public  notice  of 
their  ideas  in  high  places.  Even  the  Fed- 
eral Communications  Commission  seems 
unusually  responsive  and  sympathetic 
toward  proposals  some  of  which  are 
radical  and  of  an  untried  nature.  Ap- 
parently, too,  it  is  easier  to  "break  the 
headlines"  with  a  new  television  idea 
than  in  almost  any  other  field. 

Television's  Essential  Vitality 

Whenever  any  difficulties  arise  in  the 
daily  practice  of  television  broadcasting 
(and  they  do  occur,  as  in  almost  any 
other  field),  the  tendency  is  to  shout: 
"Hold  everything!"  This  is  usually  fol- 
lowed by  a  period  of  study,  standstill, 
and  inquiry  which  also  becomes  a  period 
of  uncertainty  and  partial  stagnation.  It 
is,  in  fact,  a  tribute  to  the  vitality  of  tele- 
vision that  it  has  survived  the  disorder, 
injury,  delays,  and  confusion  which  re- 
sult from  serious  proposals  to  accept  un- 
tried new  ideas,  usually  without  adequate 
field  tests  or  manufacturing  experiences. 

These  comments  should  not  be  misin- 
terpreted as  indicating  opposition  to  all 


changes  in  television.  Tested  and  advan- 
tageous changes  should  always  be  ac- 
cepted, on  reasonable  notice  and  at  an 
appropriate  time.  Let  us  admit,  for  ex- 
ample, that  television  could  use  a  num- 
ber of  additional  channels  below  300 
mc,  or  even  below  200  mc.  The  stations 
that  would  be  established  might  not  be 


able  to  operate  economically,  but  at  least 
the  addition  of  numerous  stations  would 
satisfy  applicants,  simplify  the  task  of 
the  regulatory  authorities,  and  lead  to 
increasingly   vigorous    competition. 

Whether  such  competition  would  im- 
prove the  service  of  any  stations  and 
whether  it  might  not  lead  to  the  untimely 
demise  of  some  stations  is  another  matter. 

Encourage  Experimental  Research 

But  let  us  admit  also  that  it  is  possible 
that  some  day  television  broadcasting 
above  500  mc,  or  even  above  5000  mc, 
will  be  found  useful.  To  be  sure,  opera- 
tion at  these  higher  frequencies  will  re- 
quire high  power,  possibly  new  tech- 
(Continued  on  page  30) 


Strobo  Discs  for  Both  60-  and  50-Cycle  Power  Supply 

From  the  hinterlands  of  the  U.  S.  as  well  as  from  foreign  fields  come  questions  anent  to  a 
practical  service  item  bearing  upon  a  method  for  checking  projector  running  speed 
which  appeared  in  IP  several  months  ago  and  which  was  applicable  only  in  those  situa- 
tions where  60-cycle  current  was  available.  In  the  interest  of  clarity,  and  for  the  pur-  ' 
pose  of  comparison,  we  present  here  the  original  item  and  an  addendum  which  describes 
the  use  of  this   device  with   50-cycle  current. 

CUT  out  one  of  the  Strobo  discs  shown 
here  and  paste  it  to  the  end  of  a 
sprocket,  using  household  cement  or 
shellac.  After  the  cement  has  thoroughly 
dried,  hold  a  lamp  in  front  of  the  disc 
and  observe  its  motion.  The  lamp,  of 
course,  must  be  plugged  to  a  60-cycle 
current  source.  For  better  results,  use  a 
small  neon  light  available  at  any  radio 
store. 

If  the  Strobo  disc  appears  to  rotate 
in  the  same  direction  as  the  sprocket,  the 
projector  is  running  above  normal  speed. 
If  it  appears  to  rotate  in  the  opposite 
direction,  it  is  running  below  normal 
speed.  If  it  appears  to  stand  still,  it  is 
running  at  the  normal  speed  of  360  r.p.m. 

If  the  projector  is  running  above  or 
below  normal  speed,  the  exact  speed 
may  be  determined  by  counting  the  num- 
ber of  times  the  disc  appears  to  rotate  in 
one  minute.  For  example,  suppose  that 
the  disc  appears  to  rotate  six  times  per 
minute  in  the  same  direction  as  the 
sprocket  is  turning:  then  the  actual 
speed  of  the  sprocket  is  360  plus  6,  or 
366  r.p.m.  If  the  disc  is  turning  in  the 
opposite  direction,  then  the  speed  is  360 
minus  6,  or  354  r.p.m. 

Expressed  in  terms  of  film  in  feet  per 
minute,  the  speed  for  both  these  condi- 
tions will  be    (for  above  normal)  : 

360  +  6 


360 

A    JU     

or  for  a 

speed  below  normal: 

360  —  6 

-X90  = 

88.5  feet  per 

min 

360 

Now, 

the    disc 

shown    here 

was 

de- 

signed  for  60-cycle  current.  Placed  on  a 
shaft  which  rotates  at  360  r.  p.  m.,  or 
6  r.p.s.,  the  disc  contains  20  segments  of 
each  color  (black  and  white),  thus  120 
segments  pass  a  given  point  each  second. 
An  incandescent  light  operating  on  60- 
cycle  power  radiates  120  pulses  of  maxi- 
mum radiant  intensity  per  second,  thus 
one  segment  of  the  disc  passes  a  given 
point  per  each  light  flash,  and,  if  the 
shaft  speed  be  correct,  the  pattern  ap- 
pears to  stand  still. 

50-Cycle  Current  Requisites 

The  use  of  this  disc  with  50-cycle  cur- 
rent is,  however,  quite  a  different  proposi- 
tion. The  50-cycle  current  flashes  only 
100  times  per  second,  thus  the  pattern 
shown  here  would  move  rapidly  when 
the  shaft  speed  is  correct. 

However,  if  the  number  of  segments 
on  the  disc  be  increased  to  50,  there 
would  be  300  segments  passing  a  given 
point  per  second,  which  figure  is  exactly 
three  times  the  rate  at  which  light  flashes 
with  50-cycle  current.  Under  this  setup 
the  pattern  will  again  appear  to  stand 
still  at  the  correct  sprocket  speed. 

No  lesser  number  of  segments  than 
300  will  satisfy  the  requisites  of  50-cycle 
current  that  there  be  an  integral  number 
of  segments  and  that  the  number  of 
segments  passing  a  given  point  per  light 
flash  must  likewise  be  an  integer. 


18 


INTERNATIONAL  PROJECTIONIST 


February  1949 


New  Motiograph-Hall  H-l  Arc  Lamp 

Rotating  Arc,  Reflector-Type  Unit  Rated  at  75-115  Amps. 


WB 


Detailed  view  of  the  Motiograph-Hall  75-115  ampere  H.I.  lamp,  showing 
carbon   positioning,   rotating   positive,   and    16-inch    reflector. 


MOTIOGRAPH  has  rounded  out  its 
line  of  projection  and  sound  equip- 
ment and  has  made  a  noteworthy  con- 
tribution to  the  ever-increasing  demand 
for  more  screen  light  with  the  introduc- 
tion of  its  new  Motiograph-Hall  high- 
tensity  carbon  arc  lamp,  now  ready  for 
general  distribution.  Originally  designed 
for  drive-in  theatres  with  their  tremen- 
dous picture  sizes  and  extremely  long 
viewing  distances,  this  new  lamp  is 
equally  adaptable  for  large  enclosed 
theatre  operation. 

Especially  interesting  in  connection 
with  this  development  is  the  reappear- 
ance in  a  major  projection  enterprise  of 
the  name  of  Hall,  which  will  be  readily 
identified  by  veteran  projectionists  with 
Theodore  0.  Hall,  inventor  of  the  old- 
time  Sunlight  Arc  and  founder  of  Hall  & 
Connolly,  for  many  years  practically  the 
sole  manufacturers  of  rotating  high-inten- 
sity arc  lamp.  Hall  is  now  associated 
with  Motiograph,  and  having  designed 
this  new  lamp,  he  will  supervise  its  manu- 
facture. 

Rotating  Arc,  16-Inch  Mirror 

It  was  perhaps  inevitable,  therefore, 
that  this  new  lamp  should  utilize  a 
rotating  arc,  although  its  combination 
with  a  reflector  mirror  instead  of  the 
conventional  condenser  optical  system 
which  invariably  has  been  used  with  this 
type  of  arc  constitutes  a  sharp  departure 
from  conventional  procedure. 

The  Motiograph-Hall  lamp  utilizes  a 
16-inch  mirror,  and  it  may  be  operated 
with  either  a  9-  or  11-mm  positive  carbon 
in  conjunction  with  a  5/16  x  9-inch  nega- 
tive. The  lamp  is  designed  to  operate 
efficiently  within  the  range  of  from  75  to 
115  amperes. 


The  reason  for  the  adoption  of  the 
rotating  arc  is,  of  course,  obvious:  it 
permits  the  use  of  larger  carbon  trims 
burned  at  higher  amperages  than  is 
possible  with  a  straight  arc;  moreover, 
such  an  arc  enables  a  more  precise  posi- 
tioning of  both  negative  and  positive 
carbons  in  relation  to  each  other  and 
thus  effects  a  more  efficient  carbon- 
burning  pattern  in  terms  of  a  higher 
level  of  incandescence  in  the  positive 
crater,  with  accompanying  greater  bril- 
liance. 

Under  these  circumstances,  the  use  of 
a  larger  light-collecting  medium — in  this 
case  a  16-inch  mirror — is  definitely  indi- 
cated. 

It  is  apparent,  therefore,  that  the  indi- 
vidual worth  of  these  elements  is  beyond 
question;  but  their  use  in  combination 
gives  rise  to  a  train  of  speculation  which 
may  not  be  satisfied  on  any  basis  other 

Ultra-Sensitive  Color  Analyzer 

A  new  machine  which  can  tell  blue  from 
blue  and  red  from  red  has  been  developed. 
It  is  an  electric  color  analyzer  so  sensitive 
that  it  will  detect  other  color  differences  too 
small  to  be  seen  by  the  average  human  eye, 
it  is  announced  by  Ansco.  The  instrument 
can  measure  1/100,000,000  of  the  light 
emitted  by  an  automobile  headlamp. 

Production  of  Ansco  color  film  prompted 
the  need  for  such  a  device,  and  it  is  expected 
to  play  an  important  part  in  cancer  research 
on  the  basis  of  recent  studies  which  indicate 
that  blood  changes  color  during  progression 
of  the  disease.  Although  designed  primarily 
for  photographic  work,  the  instrument,  known 
as  the  Ansco  color  densitometer,  can  be 
adapted  to  scores  of  other  uses  in  many  other 
fields,  such  as  measuring  or  matching  colors 
in  textiles,  paints  and  dyes,  and  in  medical 
research. 


than  extensive  use  under  actual  field 
conditions — so  many  hours  of  use  per 
day  over  a  given  period.  Motiograph 
stresses  the  design  feature  which  permits 
more  than  adequate  ventilation,  and  it 
is  taken  for  granted  that  their  own  field 
tests  have  justified  this  assertion. 

Carbon  Trim,  Lumen  Production 

The  9-  and  11-mm  carbons  cited  as 
suitable  for  use  in  the  M-H  lamp  (along 
with  a  10-mm  trim  understood  to  now 
be  in  the  experimental  stage)  are  the 
uncoated  type,  that  is,  they  are  "bare" 
without  copper  coating. 

Motiograph  asserts  that  this  new  lamp 
will  produce  19,000  screen  light  lumes 
when  operated  at  only  85  amperes.  This 
is  an  extremely  high  figure,  particularly 
when  compared  with  the  18,500  lumens 
produced  by  a  condenser-type  arc  lamp 
when  operated  at  170  amperes.  While 
having  no  doubt  that  Motiograph  has 
fully  field-tested  this  lamp  in  terms  of 
light-producing  ability,  IP  will  have  to 
withhold  comment  on  this  figure  until 
such  time  as  laboratory  test  results  are 
available. 

Operationally,  this  new  lamp  offers  no 
unusual  problem  for  the  experienced 
projectionist,  and  in  any  event  Motio- 
graph has  made  available  for  all  installa- 
tions an  unusually  detailed  instruction 
book  which  should  serve  to  surmount  any 
possible  difficulty. 

The  lamp  has  an  automatic  focus 
control — a  combination  optical  and  elec- 
trical device — which  serves  to  hold  the 
crater  of  the  positive  carbon  at  the  exact 
focal  point  of  the  mirror  within  the  very 
narrow  limits  of  7/1000th  inch,  a  margin 
which  renders  practically  impossible 
those  light  variations  which  impair  the 
screen  image. 

Once  the  lamp  is  struck,  the  projec- 
tionist need  only  watch  a  pilot  light 
which  indicates  lamp  performance,  and 
an  audible  signal  is  employed  as  a  warn- 
ing of  either  failure  of  control  power  or 
a  shortage  of  carbon  in  the  positive 
holder.  The  light  flashes  when  the  auto- 
matic control  goes  into  action.  When 
(Continued  on  page  31) 


Exterior   of   Motiograph-Hall   lamp. 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


19 


IN  THE 


SPOTLIGHT 


By 

HARRY 

SHERMAN 


UNIVERSAL  Pictures  recently  an- 
nounced that  its  1948  operations  up 
to  October  30  last  resulted  in  a  net  loss 
of  some  $3  million,  as  compared  with  a 
net  profit  of  $3l/2  million  for  1947.  This 
set  off  another  series  of  "I  told  you  sos" 
by  those  newspaper  and  radio  columnists 
who  almost  daily  predict  the  imminent 
death  of  the  movie  industry  as  now 
set  up. 

While  we're  not  privy  to  the  account- 
ing methods  employed  by  Universal,  we 
think  it  very  significant  that  the  com- 
pany's 1948  revenues  were  the  highest 
in  its  history,  excepting  1947.  Possibly 
a  partial  answer  to  this  perplexing  ques- 
tion lies  in  the  following  quote  from  the 
nationally  syndicated  movie  column  by 
Sheilah  Graham  under  date  of  Feb.  1: 

"Deanna  Durbin  will  get  $225,000  for 
three  films  she  won't  make"  (italics  ours). 
"It's  a  bonus  of  $85,000  per.  By  contract 
with  U-I  she  is  supposed  to  make  them 
by  August,  but  probably  will  make  none. 
Yet  she   collects." 

Not  meaning  to  pour  it  on  Universal 
exclusively,  we  quote  another  engaging 
item  from  the  same  column: 

"Paulette  Goddard  wouldn't  say  yes  or 
no  for  a  whole  year  on  'Anna  Lucasta.'  If 
she  gives  in,  it  will  be  at  $17,500  a  week, 
plus  20%  of  the  profits." 

Now,  in  Miss  Durban's  case  the  boys 
are  forced  to  pay  off  on  an  idiocy  already 
consummated;  but  in  Miss  Goddard's  set- 
up they  are  actually  begging  for  the 
same  dose — only  more  of  it.  Miss  God- 
dard undoubtedly  has  many  charms,  not 
all  of  which  are  hidden,  but  they  seem 
to  come  awfully  high  at  $17,500  per 
week  plus.  Has  anybody  ever  calculated 
the  overall  box-office  draw  on  the  God- 
dard pictures?  We  doubt  it,  if  only 
because  the  executives  whose  job  it  is 
to  do  such  chores  are  too  busy  "effecting 
economies"  in  terms  of  layoffs,  wage 
slashes  and  production  "short  cuts" — 
with  the  latter  meaning  investing  a  pic- 
ture with  an  odor  that  definitely  is  not 
perfume. 

Two  items:  The  Bureau  of  Internal 
Revenue  reports  that  Uncle  Sam  took 
only  2%  less  tax  money  at  theatre  box- 
offices  during  1948  than  he  did  in  1947. 
Two   top   Universal   officials — the   chair- 


man of  the  board  and  the  president — 
state  in  print  in  U's  annual  report  that 
box-office  takes  are  off  "less  than  10% 
compared  with  1947,"  the  latter  being 
merely  a  "phenominal"  income  year. 

You  add  it  up — and  don't  forget  the 
answer  when  it's  needed. 

•  Bill  Thompson,  the  aggressive  busi- 
ness manager  for  Local  171,  Pittsburgh, 
Penna.,  did  not  accept  the  usual  excuse 
advanced  by  many  Tv  stations  that  "we 
are  in  the  experimental  stage"  when  the 
new  remote  Tv  station,  WDTV,  made  its 
bow  in  Pittsburgh  recently.  He  was 
successful  in  placing  Gene  Welday,  a 
Local  171  man,  as  projectionist  for  the 
station. 

•  Because  of  the  vastness  of  the  terri- 
tory it  covered,  making  it  necessary  for 
many  of  its  members  to  travel  as  much 
as  500  miles  to  attend  the  union  meet- 
ings, the  jurisdiction  of  Local  720,  Las 
Vegas,  Nev.,  was  divided  with  the  newly 
chartered    Local     730,     Barstow,     Calif. 

(See  "IA  Elections"  elsewhere  in  this 
issue  for  a  listing  of  elected  officers.) 

•  Julius  J.  ("Chief")  Schaefer,  who 
served  25  terms  as  president  of  Local 
249,  Dallas,  Tex.,  was  presented  last 
month  with  a  gold  life  membership  card. 
The  presentation  was  made  on  behalf  of 
the  membership  by  Paul  W.  Humphries, 
newly  elected  president  of  the  Local. 

Born     in    Abilene,    Texas,    in     1888, 
Schaefer  operated  the  first  projector  to 


J.  J.  Schaefer  (left)   receiving  gold   life  mem- 
bership card  from   President  P.  W.   Humphries 
of  Dallas  Local  249. 


hit  that  town  in  1906,  and  that  was  the 
beginning  of  a  long  and  varied  career  in 
the  movie  industry.  He  migrated  to 
Dallas  in  1912  where  he  helped  to 
organize  Local  249,  and  two  years  later 
he  was  elected  to  his  first  term  as  presi- 
dent. 

In  addition  to  his  regular  job  as  chief 
projectionist  at  the  Palace  Theatre — a 
job,  incidentally,  he  has  held  since  the 
house  opened  in  1921 — he  is  in  charge  of 
a  repair  shop  on  Dallas'  Film  Row  and 
also  maintains  a  shop  in  his  home.  He 
is  loved  and  respected  by  his  fellow 
craftsmen  for  his  readiness  to  lend  a 
helping  hand  to  those  in  need.  In  other 
words,  an  all-around  swell  guy. 

•  Wilbur  L.  Parker,  Local  323,  Spring- 
field, 111.,  died  last  month  at  Veteran's 
Hospital,  Jefferson  Barracks,  Mo.  "Web," 
as  he  was  known  to  all  his  friends,  was 
a  veteran  of  World  War  I  and  served  at 
various  times* as  treasurer  and  recording- 
secretary  of  the  Local.  He  was  a  mem- 
ber of  the  American  Legion,  Post  32,  and 
of  the  Masonic  Order. 

•  The  father  of  Jim  Gorman,  president 
of  Chicago  Local  110,  died  early  this 
month  at  the  age  of  88.  Jim  was  on  his 
way  to  the  Local's  headquarters  to  attend 
the  regular  monthly  meeting  when  he 
received  word  of  his  father's  death,  but 
he  continued  with  his  official  duties  until 
the  business  of  the  meeting  was  finished. 

•  At  a  special  meeting,  Irving  A.  Weiss 
former  vice-president  of  Local  650,  West- 
chester Co.,  N.  Y.,  was  unanimously 
elected  president  to  succeed  Emil  Smith, 
resigned.  Anthony  Dente,  long  active  in 
Local  affairs,  was  elected  to  fill  the  post 
of  vice-president,  vacated  by  Weiss. 

•  Human  Interest  Note :  For  many  years 
John  J.  Murdock  was  a  power  in  show 
business.  He  was  vice-president  and 
general  manager  of,  first,  the  old  Keith 
Circuit,  then  the  Keith-Albee  organiza- 
tion, and  finally  of  RKO,  and  as  such 
he  wielded  tremendous  power.  He  knew 
managers,  agents,  actors,  bankers,  union 
officials,  and  all  the  other  diverse  per- 
sonalities that  go  to  make  up  the  enter- 
tainment    world,     and     he     contributed 


20 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


mightily  to  the  making  of  many  a  career. 

Withal,  John  J.  Murdock  was  a  warm 
and  friendly  man.  He  knew  many  bums, 
too,  and  he  turned  nary  a  one  of  them 
away.  He  was  aptly  called  Mr.  Show 
Business.  It  was  said,  too,  that  he  was 
the  best  friend  in  a  manager's  spot  that 
the  IA  ever  had. 

John  J.  Murdock  died  recently  and 
was  buried  in  Hollywood.  Twenty-seven 
(27)  mourners  attended  the  church 
services. 

Fame?     Friendship? 

•  John  P.  Flaherty,  Local  163,  yLouis- 
ville,  Ky.,  evidently  is  well  on  his  way 
to  break  the  office-holding  record  in  the 
IA.  He  was  recently  reelected  to  his 
25th  term  as  business  agent  for  the 
Local. 

•  Bill  Canavan,  St.  Louis  Local  143  and 
former  IA  president,  became  a  grand- 
father for  the  sixth  time.  No  danger 
of  the  Canavan  clan  becoming  extinct. 

•  We  were  glad  to  hear  that  Newt 
Wallis,  former  president  of  Local  105, 
London,  Ont.,  is  well  on  the  road  to  com- 
plete recovery  from  a  serious  illness  that 
kept  him  off  his  job  for  the  past  several 
months. 

•  A  special  vote  of  appreciation  is  due 
Louis  B.  Goler,  member  of  Local  253, 
Rochester,  N.  Y.,  for  his  splendid  and 
untiring  effort  to  bring  a  little  cheer  into 
the  lives  of  many  war  veterans  who  are 
still  hospitalized.  Strictly  on  his  own, 
Lou  buys  smokes  for  these  unfortunate 
shut-ins,  runs  pictures  for  them  regularly 
each  week,  and  does  whatever  he  can 
to  help  brighten  their  dreary  days. 

•  Mike  Mungovan,  business  agent  of 
Local  25,  Rochester,  N.  Y.,  for  more 
years  than  we  can  remember,  and  gener- 
ally known  as  the  "Grand  Old  Man," 
was  named  honorary  president  of  the 
Central  Trades  and  Labor  Council.  Mike 
presided  at  the  installation  last  month 
of  the  Council's  newly  elected  officers. 

•  Six  more  projectionists  were  inducted 
into  Famous  Players  Canadian  Corp.'s 
25-year  Club.  Each  new  member  was 
offered  his  choice  of  either  a  gold  watch 
or  a  $100  government  bond,  in  addition 
to  a  diamond  lapel  button  denoting  25 
years  service  with  the  company.  The 
new  projectionist  members  are  John 
Sears,  Regina  Local  295;  A.  C.  Forwell, 
Kitchener  Local  357 ;  W.  J.  Newman  and 
H.  L.  McLean,  London  Local  105;  A.  C. 
Roberts,  Brantford  Local  582,  and  J.  J. 
Rochester,  Toronto  Local  173. 

•  Bradley  Callahan,  business  agent  of 
Local  685,  Concord,  N.  H.,  was  reelected 
to  serve  a  second  term  as  AF  of  L  repre- 
sentative  at  the   New   Hampshire   State 


First  Payment  Under  Local  110-Exhibitor  Pension  Plan 


Marking  a  milestone  in  theatrical  labor 
history,  the  first  pension  check  issued 
under  the  agreement  consummated  be- 
tween Chicago  Local  110  and  the  ex- 
hibitor's association  last  August  was 
tendered  to  Joseph  Greenberg,  75,  at  a 
regular  meeting  on  Feb.  3  last.  Several 
hundred  members  witnessed  the  event. 
Greenberg,  a  member  of  Local  110  since 
1907,  was  tendered  a  check  for  $500, 
representing  retroactive  payments  dating 
from  September  I  last  year.  He  will  re- 
ceive at  least  $100  monthly  for  life. 

The  agreement,  drafted  six  months 
ago,  provided  for  a  10%  wage  increase 
which  in  its  entirety  goes  into  a  fund, 
jointly  administered  by  two  representa- 
tives each  from  Local  110  and  the  ex- 
hibitors association,  to  be  used  for  disa- 
bility and  retirement  payments,  two 
weeks  vacation  annually  for  every  mem- 
ber, and  increased  sick  and  death  bene- 
fits. 

Sick  benefits  are  $30  weekly  for  the 
first  10-week  period  and  $20  weekly 
thereafter,  while  the  death  payment  is 
$2,000.  Hereto  fort,  the  Local  110  mem- 
bership paid  a  special  assessment  for 
each  member's  death,  and  only  60%  of 
the  membership  enjoyed  paid  vacations. 
Withal,  under  the  new  plan  individual 
dues  are  reduced  $100  annually. 

Business  manager  Gene  Atkinson,  who 
with  Clarence   Jalas,   secretary,   are   the 


Business    manager    Gene    Atkinson    presenting 

$500  pension  check  to  Joseph  Greenberg,  under 

Local  110  retirement  plan. 

Local  110  administrators  of  the  plan, 
said  that  the  fund  now  totals  $100,000 
and  that  he  foresaw  the  growth  of  this 
figure  to  more  than  $2  million  within  the 
five-year  span  of  the  agreement.  It  was 
announced  that  27  Local  110  men  who 
were  permanently  disabled  while  work- 
ing now  receive  $100  monthly  from  the 
fund. 

The  amount  of  individual  pension  and 
disability  payments,  of  course,  is  pre- 
dicated upon  the  total  amount  of  money 
available  in  the  fund  for  distribution, 
but  in  no  case  will  it  fall  short  of 


Legislature.  He  informed  us  of  the  fight 
now  being  waged  by  the  combined  CIO 
and  AF  of  L  forces  to  repeal  anti-labor 
legislation  in  his  state.  They  know  they 
have  a  tough  fight  on  their  hands,  but 
with  men  like  Bradley  Callahan  in  their 
corner,  we  feel  certain  they  will  come 
out  on  top. 

•  Out-of-town  visitors  for  the  month  of 
January:  Joe  Nuzzolo  and  Walter  Diehl, 
president  and  business  agent,  respec- 
tively, Boston  Local  182;  Richard  Fitz, 
business  agent,  Local  534,  New  Bruns- 
wick, N.  J.;  Sydney  T.  Clark  and  Harvey 
Slater,  secretary  and  treasurer,  respec- 
tively, Providence  Local  223. 

•  St.  Louis  Local  143  has  purchased  a 
print  of  the  IA  documentary  film  and 
is  making  it  available  to  all  IA  Locals 
in  and  around  St.  Louis.  This  fine  and 
generous  gesture  by  the  officers  and  mem- 
bers of  143  has  occasioned  considerable 
favorable  comment. 

•  Mrs.  Catherine  O'Toole  Walsh,  mother 
of  IA  President  Dick  Walsh,  died  at  her 
Brooklyn,  N.  Y.,  home  on  January  11. 
Her  age  was  74.  Mrs.  Walsh,  a  widow, 
is  survived  by  five  sons,  including  Dick; 


three  daughters  and  a  sister.  Represen- 
tatives of  many  IA  Locals  attended  the 
funeral. 

•  John  Reisser,  one  of  the  oldest  mem- 
bers of  New  York  Local  306,  is  now  a 
widower  after  36  years  of  happy  married 
life.  Mrs.  Reisser  died  suddenly  last 
month,  leaving  John  disconsolate. 

•  Frank  Galluzzo,  vice-president  of  Chi- 
cago Local  110  and  former  grand  secre- 
tary-treasurer of  the  TMA  (Theatrical 
Mutual  Association),  was  reelected  presi- 
dent of  TMA  Lodge  No.  4. 

•  From  time  to  time  we  hear  of  projec- 
tionists starting  sideline  ventures.  The 
latest  to  come  to  our  attention  is  Joe 
Shore,  member  of  Hollywood  Local  165, 
who  recently  opened  a  ceramics  shop 
known  as  the  "Milene  Shop"  at  6673 
Hollywood  Blvd.  The  Shore  brothers, 
of  whom  there  are  four,  are  all  members 
of  the  IA — Marty  and  Phil,  members  of 
Detroit  Local  199;  and  Joe  and  Jim, 
Hollywood  Local  165. 

•  Robert  W.  Greer,  now  serving  his  14th 
consecutive  term  as  president  of  Local 
386,  Columbus,  Ohio,  recently  contrib- 
uted an  article  to  a  local  newspaper  in 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


21 


which  he  deplored  the  lack  of  exhibitor 
interest  in  the  unsafe  and  unsanitary 
conditions  existing  in  many  projection 
rooms.  He  cannot  understand  Mr.  Ex- 
hibitor's reluctance  to  spend  a  very  small 
part  of  his  huge  profits  of  the  lush  years 
in  providing  his  projectionist  employes 
with  decent  working  conditions.  In  his 
article,  Greer  refers  to  many  projection 
rooms  as  "booby  traps". 

We  should  like  to  inform  Brother  Greer 
that  exhibitor  "good  will"  usually  stops 
short  at  the  projection  room  door.  He 
will  spend  oodles  of  dough  for  fancy 
trimmings  for  the  front  of  the  theatre, 
but  becomes  panicky  at  the  thought  of 


spending  an  extra  dollar  or  two  for  the 
good  and  welfare  of  the  key  men  in  his 
theatre — the  projectionists. 

•  Preparations  are  now  under  way  for 
the  35th  anniversary  celebration  of  Local 
323,  Springfield,  111.,  the  committee  for 
which  will  bend  every  effort  to  insure 
the  attendance  of  a  representative  group 
of  prominent  IA  personalities. 

•  Recording  Secretary  Nick  Bonansinga, 
Springfield  Local  323,  has  taken  a  leave 
of  absence  from  his  official  duties  in  an 
effort  to  regain  his  health.  Nick's  dad, 
Sam,  is  business  agent  of  Stagehands 
Local  138  as  well  as  president  of  the 
Springfield  Federation  of  Labor. 


PROJECTION    NOTABLES   AT  25-30    PARTY 


P.  A.  McGuire  (Better  Projection  Pays)  Feted  by  25-30 


THE  recent  annual  installation  of  offi- 
cers of  the  25-30  Club  of  New  York 
City  provided  the  setting  for  a  stirring 
tribute  to  P.  A.  McGuire  in  recognition 
of  his  many  substantial  contributions  to 
both  the  craft  and  the  art  of  projection 
over  a  period  of  many  years. 

While  the  25-30  Club  provided  the 
setting,  it  remained  for  the  New  York 
State  Association  of  Projectionists  to 
compress  the  eulogistic  oratory  directed 
at  Mac  into  a  beautiful  bronze  plaque 
which  said  it  all — only  better  and  shorter. 
Not  to  be  outdone,  the  Club  presented 
Morris  J.  Rotker,  retiring  prexy,  with  a 
similar  plaque  which  expressed  the  or- 
ganization's appreciation  for  his  fine 
leadership  during  1947-1948.  The  Club 
also  honored  Larry  Davee,  of  Century 
Projector  Corp.,  by  tendering  him  a  gold 
honorary  life  membership  card. 

Space  limitations  do  not  permit  a  de- 
tailed list  of  all  those  present,  but  the 
goodly  turnout  included  prominent  per- 
sonalities within  and  without  the  movie 
business.  Numbered  among  these,  of 
course,  was   a  group  of  ranking  execu- 


PIONEER    IN    UNION,    CLUB    SPONSOR 

Bob   Goldblatt   enjoys   the   dual    distinction    of 

having    launched    IA    Local    306    as    well    as 

sponsored  the  25-30  Club. 

tives  of  Mac's  business  associates  in 
International  Projector  Corp.  and  in  Na- 
tional Theatre  Supply  Co.  The  accom- 
panying photographs  mirror  various 
phases  of  the  evening's  proceedings  and 
the  personalities  identified  therewith. 
Mac's    acknowledgment    of   the    many 


NEWLY-ELECTED  OFFICERS  OF  25-30  CLUB   OF  NEW  YORK  ARE   INSTALLED 


Left  to  right:  John  Krulish  (International  Projector  Corp.),  trustee;  Ed  Dougherty  (IA  Local  384, 

Hudson  County,  N.  J.),  sergeant-at-arms;  Morris  Klapholz  (Local  306),  secretary;  Al  Kaye  (Local 

384),  vice-president;   Cecil    R.   Wood,   Sr.    (Local   306),   president;   and    Ben   Stern    (Local    306), 

treasurer.    All  these  officers  will  serve  for  one  year. 


In  the  usual  order  (front  row):  P.  A.  McGuire 
(International  Projector  Corp.),  recipient  of  a 
bronze  plaque;  Larry  Davee  (Century  Projector 
Corp.),  tendered  a  gold  card;  Harry  Sherman 
(IP),  who  served  as  master  of  ceremonies; 
Morris  Rotker  (Local  306),  outgoing  president 
who  also  received  a  gold  card;  and  Cecil  R. 
Wood,    Sr.    (Local    306),    incoming    president. 

tributes  accorded  him  during  the  evening 
so  aptly  expressed  his  philosophy  of  that 
which  he  strove  through  many  years  to 
accomplish  and  which  won  for  him  the 
friendship  of  thousands  of  projectionists 
in  America,  that  it  is  recorded  here  for 
the  entire  craft  to  see: 

"If  I  have  accomplished  anything  in  this 
field  it  is  because  I  became  convinced  that 
'Better  Projection  Pays',  and  that  the  pro- 
jectionist is  largely  responsible  for  good 
projection. 

"Over  a  long  period  of  years  I  have  tried 
rather  persistently  to  make  others  feel  the 
same  way.  Projection  equipment  is  scien- 
tifically designed  and  precision  built. 
Changes  in  any  of  the  many  products  used 
in  connection  with  the  taking,  making  and 
showing  of  motion  pictures  will  make  the 
conscientious,  competent  craftsman  in  the 
projection  room  even  more  necessary. 

"Similar  ideas  have  been  expressed  before, 
but  it  does  no  harm  to  repeat  them  from 
time  to  time." 

Indicative  of  Mac's  widespread  con- 
tacts in  projection  circles  were  congratu- 
latory messages  from  Bill  Canavan,  for- 
mer IA  president,  and  Stanley  Perry, 
chief  projectionist  at  the  Empire  Theatre, 
London,  England. 

Portentous  Prophecies — Help  Us! 

Dr.  Ralph  Bienfang,  University  of  Okla- 
homa: "Don't  be  surprised  if  the  perfume 
advertisement  in  your  daily  newspaper  some 
day  smells  fetchingly  lovely,  while  on  the 
next  page  the  butcher's  ad  gives  off  with  a 
steaky  scent  mingled  with  the  odor  of  frying 
onions." 

This  recalls  the  abortive  attempt  of  sev- 
eral "inventors"  to  invest  certain  motion 
picture  sequences  with  specific  odors  indige- 
nous to  the  character  of  the  scene  being 
shown.  Fact!  as  several  U.  S.  patent  appli- 
cations attest. 


22 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


Condensers  in  Combination  with  Magnetic  Coils 


IN  CONNECTION  with  condensers,  it 
is  of  interest  to  note  here  the  term  po- 
tential difference.  The  earth  is  as- 
sumed to  be  at  zero  potential,  therefore 
any  bodies  having  a  different  potential 
from  earth  will  produce  a  movement  of 
electrons  to  or  from  the  earth.  A  nega- 
tively-charged body,  i.e.,  one  having  a 
surplus  of  electrons,  will,  when  connected 
to  earth,  lose  its  surplus  electrons  and 
assume  the  same  potential  as  earth;  op- 
positely, if  a  positively-charged  body  be 
connected  to  earth,  there  will  be  a  move- 
ment of  electrons  to  that  body. 

Figures  1  and  2  show  just  how  these 
effects  occur.  Therefore,  the  relative  po- 
tential of  any  charged  spheres,  plates,  or 
even  wires  or  cables,  to  earth  is  very 
often  an  important  point. 

Capacity  can,  of  course,  exist  between 
any  two  bodies  which  are  at  a  different 
potential.  The  capacities  between  par- 
allel plates,  wires,  cables  and  outer 
sheath  and  inner  conductor  of  metal- 
sheathed  cables  are  often  considerable, 
and  the  methods  of  determining  such 
capacities  are  often  most  difficult  to 
perform.  Figs.  3  and  4  illustrate  parallel 
wires  and  concentric  cables,  also  the 
resultant   effects. 

Electrostatic  Screening 

To  minimize  the  unwanted  effects  of 
capacity  between  certain  bodies,  a 
method  known  as  electrostatic  screening 
is  employed;  thus  two  bodies  which 
would  normally  produce  an  electric  field 
can  be  prevented  from  doing  so  by  means 
of  an  earthed  metallic  screen  placed 
between  them  (Fig.  5).  The  basic  action 
of  screening  is  that  the  tubes  of  force 
do  not  exist  between  the  screened  bodies: 
they  always  terminate  on  the  interposed 
metallic  screen  or  screens. 

The  same  general  idea  is  used  in 
magnetic  screening  of  high  frequencies 
where  non-magnetic  screens  are  used. 
The  principle  of  action  is  that  eddy  cur- 
rents, or  small  circulating  currents,  pro- 
duce a  magnetic  field  which  is  in  opposi- 
tion to  the  original  field:  this  more  or 
less  cancels  out  the  producing  field. 
The  idea  works  just  like  the  back  e.m.f. 
in  a  magnetic  coil. 

In  low-frequency  work,  however,  ferro- 


© 


0 


FIG.  1. 


s/ 


FIG.  2. 


By   A.    BUCKLEY 

magnetic  screens  are  employed,  since  the 
magnetic  substances  readily  conduct  the 
crowded  lines  of  force  to  ground  or 
earth.     Fig.  6  illustrates  this  idea. 

Inductive  Reactance 

Consider  now  the  subject  of  inductive 
reactance.  Here  intrudes  another  form 
of  reactance,  that  due  to  capacity  (or 
capacitive  reactance).  This  property  is 
exactly  opposite  to  inductive  reactance 
in  a  physical  sense  and,  in  certain  cases, 


I  'l1 ,  ■ 


Above:  FIG.   3. 
Right:  FIG.  4. 


can  completely  neutralize  it.  The  two 
properties  can  be  likened  to  positive  and 
negative  signs  in  algebra,  as  for  ex- 
ample: 

+  1  —  1  =  0;    —8  +  8  =  0 
In  other  words,  equal  quantities  of  both 
forms    of    reactance    cancel    each    other 
out. 

Inductive  reactance  and  resistance  may 
be  represented  in  the  form  of  a  triangle, 
with  impedance  measured  upon  the  in< 
clined  line,  or  hypotenuse.  The  same 
thing,  of  course,  applies  to  capacitive 
reactance,  but  since  the  two  things  are 
opposite  in  sense,  the  triangle  must  be 
drawn  as  in  Fig.  7. 

Inductance  and  Capacity 

Relative  to  both  inductance  and  capa- 
city we  have  mentioned  the  subject  of 
frequency.  Since  frequency  plays  such 
an  important  part  in  simple  and  com- 
pound combinations  of  these  properties, 
it  seems  necessary  to  get  the  whole 
matter  straight  at  first.  Here  we  make 
two  statements,  preliminary  to  complete 
explanations: 

(a).  The    reactance    of    a    magnetic 
coil  increases  with  increase  in 
frequency. 
(b) .  The  reactance  of  a  condenser 
decreases  with  increase  in  fre- 
quency. 
It  is  not  always  clear  why  inductive  and 
capacitive  reactances  vary  with  a  change 
in    frequency,    thus    a    few    explanatory 
words  would  seem  to  be  in  order. 

In  the  case  of  a  magnetic  coil  through 
which  a  continuous  current  passes,  so 
long  as  the  current  remains  constant  the 


only  losses  in  the  coil  are  due  to  its 
resistance.  If  the  value  of  the  current 
be  changed,  then  reactance  occurs.  The 
back  e.m.f.  mentioned  in  Lenz's  Law* 
is  ever  present,  and  whatever  change 
takes  place  in  the  current  values,  that 
change  is  opposed  by  magnetic  reaction. 
If  the  current  changes  be  slow,  the  mag- 
netic reactance  is  weak;  and  as  the 
number  of  current  changes  increases  in 
a  given  time,  then  the  magnetic  reactance 
also  increases. 

Remember  (to  give  a  mechanical  an- 
alogy) a  large  flywheel  can  be  caused 
to  move  to  and  fro  at  a  very  slow  rate; 
but  attempt  to  make  it  do  so  at  a  high 
rate,  and  it  simply  does  not  move. 

Similarly,  in  a-c  work,  if  the  number 
of  periods  per  second  is  low — say,  7 — 
the  magnetic  reactance  will  be  relatively 
low  compared  with  that  sustained  at, 
say,  a  frequency  of  1,000  c.p.s.  As  the 
frequency  rises,  the  reactance  of  a  mag- 
netic coil  becomes  so  great  that  it  is 
necessary  to  either  dispense  with  the  iron 
core  or  use  one  of  iron  dust. 

The  inductance  of  a  coil  remains  the 
same  at  any  frequency,  but  a  coil  having 
a  small  inductance  will  have  a  low  re- 
actance at  low  frequencies  and  a  high 
reactance  at  high  frequencies. 

Sharply  Contrasting  Characteristics 

Inductance  and  capacity  are  as  oppo- 
site as  the  poles  in  characteristics.  This 
observation  is  amply  borne  out  by  com- 
paring the  behaviour  of  coils  and  con- 
densers at  different  frequencies.  With 
a  steady  d-c  there  is  also  a  sharp  con- 
trast in  the  behaviour  of  the  two,  for  in 
a  coil  the  only  losses  are  resistive  and 
the  current  continues  to  pass  steadily. 

In  a  condenser,  however,  after  the 
full  charging  current  has  passed,  the 
condenser  acts  as  an  insulator,  i.e.,  no 
passage  of  current  in  the  same  direction 

*  Lenz's  Law  states:  "An  induced  current  set  up  by 
the  relative  motion  of  a  conductor  and  a  magnetic  field 
always  flows  in  such  a  direction  that  it  forms  a  mag- 
netic field  that  opposes  the  motion." 


Above  left:  FIG.  5;  upper  right:  FIG.  6;  lower 
right:  FIG.  7. 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


23 


is  possible:  it  has,  therefore,  an  infinitely 
high  opposition  to  current  flow  in  that 
direction. 

It  was  stated  previously  that  a  con- 
denser possessed  capacity;  that  capacity 
is  virtually  the  same  as  that  of  a  cistern, 
or  an  egg  cup.  When  that  capacity  is 
reached — in  the  electrical  or  mechanical 
sense — no  more  of  the  essential  sub- 
stance can  be  admitted. 

At  low  frequencies  a  certain  value  of 
condenser  capacity  will  be  charged  in  a 
fraction  of  a  cycle,  and  the  current  will 
be  dormant  until  it  reverses  direction. 
As  the  frequency  rises,  the  dormant 
period  becomes  less  and  less  until  at  one 
particular  frequency  the  condenser  will 
charge  and  discharge  in  more  or  less 
perfect  time  with  each  cycle.  Above 
that  frequency,  the  condenser  will  never 
be  fully  charged,  since  the  period  of 
the  cycle  is  shorter  than  the  natural 
charging  period  of  the  condenser. 

The  higher  the  frequency,  the  shorter 
the  charging  time,  therefore  there  is 
no  dormant  period.  According  to  this 
reasoning,  at  low  frequencies  the  con- 
denser is  very  much  less  efficient  than  at 


MAX.  ^  MIN. 

FRBQ*    RESONANT  POINT     FREQ* 

FIGURE  8. 

a  high  level,  so  we  say  that  as  the  fre- 
quency rises  the  capacitive  reactance 
becomes  less. 

In  the  case  of  inductive  reactance, 
frequency  increase  means  an  increase 
in  the  reactance;  but  in  the  case  of 
capacitive  reactance,  frequency  appears 
in  the  denominator  of  the  fraction  and, 
therefore,  any  increase  in  frequency  will 
result  in  a  decrease  in  reactance. 

A  numerical  example  will  clarify  this 
statement.  If  any  whole  number  be 
multiplied  by  10,  that  number  will  be 
increased  10  times.  But  if  the  denomina- 
tor of  an  improper  fraction  be  multiplied 
by  10,  then  the  result  will  be  10  times 


smaller,    as   in   the    following    example: 
10  X  10  =  100  1/  (10  X  10)  =  100 

Taking  a  rough  example,  if  we  draw 
two  inclined  lines  showing  the  reactance 
of  both  magnetic  coil  and  a  condenser, 
as  shown  in  Fig.  8,  we  shall  find  a  point 
where  the  two  lines  intersect  and  where 
the  two  reactances  are  exactly  equal. 
This  is  known  as  the  resonant  point. 

The  point  of  resonance  varies,  of 
course,  according  to  the  amount  of  re- 
actance in  both  inductance  coil  and 
condenser:  thus  the  resonant  position  of 
a  small  capacity  and  a  large  inductance 
might  be  exactly  equal  to  a  large  capa- 
city and  a  small  inductance.  The  action 
may  be  likened  to  that  of  a  clock  where 
the  hairspring  corresponds  to  capacity, 
i.e.,  it  has  elasticity  and  is  capable  of 
storing  energy — and  the  balance-wheel 
resembles  a  magnetic  coil,  virtually  an 
electrical   flywheel. 

Now,  a  clock  escapement  will  oscillate 

at   one   frequency   provided   the   tension 

of  the  spring  remains  constant  and  that 

the  temperature  of   the   room    does  not 

(Continued  on  page  29) 


Nine  New  American  Standards  Announced  by  the  SMPE 


NINE  additional  American  Standards 
on  Motion  Pictures  are  published 
in  the  November,  1948,  issue  of  the 
SMPE  Journal,  bringing  to  49  the  num- 
ber of  new  and  revised  standards  made 
available  to  the  motion  picture  industry 
since  January,  1946.  At  that  time  the 
American  Standards  Association,  with  the 
help  of  many  SMPE  and  Motion  Picture 
Research  Council  committees,  embarked 
upan  an  expanded  standards  program 
calling  for  the  review  of  all  motion  pic- 
ture standards  approved  prior  to  the 
recent  war  and  the  reappraisal  of  all 
temporary  war  standards  developed  for 
the  use  of  the  military  services  during 
the  intervening  years. 

A  complete  subject  index  of  all  49  of 
these  standards,  contained  in  the  SMPE 
Standards  Binder  (S1/^  x  11  inches)  is 
available  through  the  SMPE  for  $8.50 
postpaid  within  the  U.S.A.,  or  for  $9  in 
U.S.  funds  when  mailed  to  a  foreign 
country. 

Among  the  nine  new  standards  is  one 
applicable  to  ASA  dimensions  for  theatre 
projection  screens.  Details  of  this  stand- 
ard follow,: 

1.    Scope  and  Purpose 

1.1  This  standard  specifies  dimensions  for 
projection  screens  used  for  viewing  motion 
pictures. 

2.    Screen  Size 

2.1  Sizes  of  screens  shall  be  in  accordance 
with  Table  A. 

2.2  The  over-all  size  shall  be  measured 
from  the  outer  edge  of  border  to  the  outer 


edge  of  opposite  border.  The  ratio  of  the  over- 
all width  to  over-all  height  shall  be  4  to  3. 

3.    Border 

3.1  A  fabric  reinforcing  border  shall  sur- 
round the  screen.  The  width  of  this  border 
shall  be  from  2.5  to  3  inches. 

4.    Grommets 

4.1  Metal  mounting  grommets,  size  No.  3 
or  No.  4,  shall  be  securely  fastened  through 
the  fabric  border. 

4.2  Grommets  shall  be  spaced  on  6-inch 


centers,  starting  from  grommets  located  at 
the  centers  of  the  four  sides  of  the  screen, 
except  that  there  shall  also  be  a  grommet  in 
each  corner  of  the  screen.  Grommets  shall  be 
set  in  a  line  parallel  to  the  edge  of  the  screen, 
with  their  centers  from  1.0  to  1.31  inches 
inside  the  outer  edge  of  the  border. 

5.    Selection  of  Screen  Size 

5.1  The  width  of  the  screen  should  be  not 
less  than  1/6  of  the  distance  from  the  center 
of  the  screen  to  the  most  remote  seat. 

5.2  The  distance  between  the  screen  and 
the  front  row  of  seats  should  be  not  less  than 
0.87  foot  for  each  foot  of  screen  width 


AMERICAN  STANDARD  DIMENSIONS  FOR  THEATRE  PROJECTION   SCREENS 


Over-oil 

Over-oil 

Minimum  Effective 

Size  No. 

Width 

Height 

Picture  Size 

of  Screen 

(feet) 

(feet) 

(feet) 

8 

8.00 

6.00 

7.50             5.50 

9 

9.00 

6.75 

8.50             6.25 

10 

10.00 

7.50 

9.50             7.00 

11 

11.00 

8.25 

10.50             7.75 

12 

12.00 

9.00 

11.50             8.50 

13 

13.00 

9.75 

12.50             9.25 

14 

14.00 

10.50 

13.50           10.00 

15 

15.00 

11.25 

14.50           10.75 

16 

16.00 

12.00 

1 5.50           1 1 .50 

17 

17.00 

-     1 2.75 

16.50           12.25 

18 

18.00 

13.50 

17.50           13.00 

19 

19.00 

14.25 

18.50           13.75 

20 

20.00 

15.00 

19.50           14.50 

21 

21.00 

15.75 

20.50           15.25 

22 

22.00 

16.50 

21.50           16.00 

23 

23.00 

17.25 

22.50           16.75 

24 

24.00 

18.00 

23.50           17.50 

25 

25.00 

18.75 

24.50           18.25 

26 

26.00 

19.50 

25.50           19.00 

27 

27.00 

20.25 

26.50            19.75 

28 

28.00 

21.00 

27.50           20.50 

29 

29.00 

21.75 

28.50           21.25 

30 

30.00 

22.50 

29.50           22.00 

NOTES : 

1.  Masking  on  each 
of  the  four  sides  of 
the  screen  is  recom- 
mended as  follows: 

1  inch  of  masking 
within  the  projected 
picture  area  on  each 
of  the  four  sides  of 
the  picture  for  every 
12  feet  of  picture 
width,  with  a  mini- 
mum of  1  inch  for 
pictures  less  than  12 
feet  in  width. 

2.  Screens  larger  than 
Size  No.  30  are  not 
specified,  as  such 
screens  are  usually 
custom-built  or  not 
in  4  by  3  ratio  due 
to    projection    angle. 


24 


INTERNATIONAL  PROJECTIONIST 


February  1949 


L  E  C  A  S  T  S 


KJKJHtUI-lTM  m%lA.*l!  ). 


SMPE  Theatre  Television  Group  Lays  it  on  the  Line 


CONFIRMING  that  which  has  been 
stated  repeatedly  in  IP,  the  Theatre 
Television  Committee  of  the  Society  of 
Motion  Picture  Engineers  has  issued  a 
28-page  printed  booklet  which,  in  out- 
lining the  present  status  of  Tv,  warns 
that  the  time  remaining  for  the  movie 
industry's  participation  in  this  new  art 
is  rapidly  growing  short  and  may  soon 
be  non-existant. 

The  report  holds  small  comfort  for 
those  who  hold  that  Tv  is  a  "passing 
fancy"  and  will  soon  bear  the  same  com- 
petitive relationship  to  film  exhibition  as 
does  radio  now;  v/hile  it  is  nothing  short 
of  devastating  to  those  who  pin  their 
hopes  on  the  gregarious  nature  of  hu- 
mans. 

Everything  is  ready  for  the  wedding 
of  the  movie  theatre  and  Tv  arts,  the 
report  states,  but  it  is  stressed  that  "fur- 
ther development  of  equipment  as  well 
as  provision  by  the  FCC  of  suitable 
channels  is  now  mainly  dependent  upon 
the  interest  shown  by  the  motion  picture 
industry." 

'Experimental'  License  Status 

The  only  transmission  channels  now 
held  by  the  motion  picture  industry 
per  se  were  those  experimental  alloca- 
tions obtained  through  the  efforts  of  the 
SMPE.  Such  allocations  may  be  trans- 
ferred into  commercial  licenses  only  if 
they  are  actively  worked,  and  the  lack 
of  interest  displayed  by  the  movie  in- 
dustry to  date  seems  to  have  convinced 
the  FCC  that  no   serious  intent  to  use 

British  Parent  Is  Issued  On  The 
Century  'C  and  'CC  Units 

A  British  patent  covering  design  features 
of  the  Century  models  C  and  CC  projector 
mechanisms  has  been  issued.  U.  S.  patents 
on  these  units  have  been  in  effect  for  some 
time  now.  Prominent  in  the  patent  claims  are 
higher  shutter  efficiency  with  less  heat  on 
the  film;  simplicity  in  gear  and  shaft  de- 
sign with  practically  100%  protection  against 
failure  due  to  bindups,  frozen  bearings,  etc.; 
the  elimination  of  lubrication  problems  by 
the  use  of  sealed-for-life  bearings,  and  the 
use  of  cushioned  gears  throughout  to  reduce 
noise  levels  and  to  eliminate  vibration. 

Featured  also  in  the  specs  are  manufac- 
turing techniques  for  greater  accuracy  of 
the  star  and  cam,  together  with  the  ground 
tooth  placement  of  the  intermittent  sprocket 
with  the  new  enlarged  diameter  (0.943"). 


these  channels  exists.  In  fact,  in  1947 
the  FCC  was  on  the  verge  of  reallocat- 
ing these  channels  to  other  services,  a 
move  which  was  prevented  only  by 
prompt  and  vigorous  action  by  the 
SMPE. 

It  must  be  remembered  that  the  SMPE 
report  is  concerned  only  with  the  appli- 
cation of  Tv  to  the  exhibition  field,  it 
being  quite  apparent  that  the  Big  Brass 
in  filmdom  are  already  moving  toward 
delivering  their  studio  properties  to  the 
Tv  people  whenever  it  suits  their  eco- 
nomic needs.  Just,  where  such  a  move 
would  leave  the  theatres  is  anybody's 
guess,  but  there  exists  no  rational  person 
who  couldn't  see  this  development  in  the 
making. 

Summary  of  SMPE  Views 

Summed  up,  the  SMPE  report  stresses 
the  following  points  of  the  theatre-Tv 
situation  as  it  now  stands: 

1.  Everything  is  in  readiness  to  go  on 
the  equipment  and  technique  fronts. 

2.  Any  further  delay  in  applying  for 
channel  allocations — even  a  delay  of  ap- 
proximately six  months — may  be  fatal  to 
the  future  well-being  of  the  exhibition 
field. 

3.  All  divisions  of  the  motion  picture 
field — production,  distribution  and  ex- 
hibition— should  unite  on  a  common  plan 
of  action. 

4.  Large  theatre  circuits  can  have 
their  own  local  or  regional  hookups. 

5.  Local  events  can  be  picked  up  by 
microwave  relays. 

6.  A  typical  theatre  installation  costs 
about  $35,000,  which  figure  could  be  re- 
duced somewhat  if  sufficient  orders  were 
forthcoming. 

7.  Experimental  licenses  are  obtain- 
able, but  they  must  be  used  to  be  re- 
tained. 

One  possible  reason  for  the  apathetic 
attitude  displayed  by  the  film  industry 
toward  Tv  to  date  is  contained  in  the 
following  excerpt  from  the  SMPE  report: 

"The  general  attitude  seemed  to  be 
that  it  might  be  possibly  to  buy  into 
the  television  industry  at  some  future 
date  and  thereby  save  the  high  cost  of 
research  and  development."  Bearing  on 
this  angle  is  the  widely  circulated  re- 
port of  recent  weeks  that  20  Century-Fox 
was  seeking  to  buy  control  of  American 
Broadcasting  Co.,  formerly  known  as  the 
Blue  Network. 


The  complete  report  of  the  SMPE 
Theatre  Television  Committee  will  be 
published  in  IP  as  soon  as  formal  re- 
lease of  the  material  can  be  obtained. 

*  *       * 

Three  possible  courses  of  action  in 
fighting  the  menace  of  Tv  to  the  theatre 
box-office  were  canvassed  by  the  recent 
convention  of  the  Theatre  Owners  of 
America  at  Washington,  D.  C.  Assigned 
to  the  Tv  committee  for  further  study 
were  these  proposals: 

1.  Apply  to  the  FCC  for  special 
theatre  Tv  channels. 

2.  Apply  individually  for  commercial 
Tv  station  licenses. 

3.  Rely  upon  distribution  of  Tv  spe- 
cial-events coverage  by  coaxial  cable  or 
some  other  technic  which  may  not  re; 
quire  FCC  approval. 

Still  to  be  mulled  over  in  committee 
are  the  first  two  possibilities:  whether 
the  application  for  licenses  shall  be  by 
the  T.O.A.  as  a  national  organization,  by 
local  units  thereof,  or  by  circuit  or  inde- 
pendent theatre  circuit  operators. 

Ready  assent  was  forthcoming  that  no 
pickup  of  material  from  regular  Tv  net- 
work broadcasts  may  be  made  without 
payment  of  some  sort  to  the  owner 
thereof,  provided  the  latter  should  ex- 
tend permission,  which  is  doubtful.  More- 
over, the  vexing  matter  of  required  in- 
clusion of  all  commercial  plugs  in  such 
program  fare  still  is  far  from  a  solution. 

*  *       * 

TELEVIEWS — Hal  Roach,  famous 
feature  and  short-subject  producer  for 
many  years,  has  forsaken  film-making  for 
theatres  to  devote  his  entire  time  to  pic- 
tures for  Tv  use.  .  .  .  The  FCC  has 
ruled  that  Paramount  Pictures  does  in 
fact  exercise  control  over  DuMont,  there- 
fore has  denied  former's  application  for 
(Continued  on  page  31) 

F-P  Canadian  Earnings  Maintained 

Earnings  of  Famous  Players  Canadian 
Corp.  for  1948  will  compare  favorably  with 
the  record  earnings  of  1947,  it  is  reported  by 
President  J.  J.  Fitzgibbons.  Because  no 
extra  dividend  was  declared,  company  was 
able  to  add  new  theatres  and  modernize 
old  ones  without  borrowing.  F.P.C.  now  op- 
erates 375  theatres  in  130  Canadian  localities. 


All  122  Fox  Midwest  theatres  in  Kansas, 
Illinois,  Iowa  and  Missouri  are  now  receiv- 
ing RCA  theatre  service  under  a  contract 
recently  signed. 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


25 


LEONARD  A.  EDWARDS— Vice- 
President,  Associated  Prudential 
Theatres,  New  York,  N.  Y. — says: 
"We  have  used  RCA  Service 
continuously  since   1929.   It 
has  never  failed  us." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


PROJECTIONISTS' 

SERVICE 
MANUAL 


$300 


COLOR:  ITS  COMPLEX  STRUCTURE 

(Continued  from  page  17) 

importance,    hue   sensation    and    bright- 
ness. 

Color  in  Hue:  The  hue  of  a  color  is 
identified  by  its  wave-length  or  its  posi- 
tion relative  to  the  spectral  band  of  vis- 
ible radiation,  which  reaches  approxi- 
mately from  400  to  700  millimicrons  and, 
when  thought  of  as  a  continuous  band, 
must  consist  of  an  infinite  number  of 
different  hues. 

The  human  eye  can  at  best  distinguish 
about  200  hues,  so  that  we  may  say  that 
our  eye  can  see  a  difference  in  two  colors 
as  long  as  the  difference  in  their  hue  is 
not  less  than  1.5  millimicrons. 

Color  Saturation:  This  attribute  of 
color  is  an  indicator  of  its  purity.  A  dye 
of  spectral  purity  would  have  100% 
saturation.  White  has  zero  saturation. 
The  amount  of  dilution  with  white  de- 
termines, therefore,  the  degree  of  satu- 
ration of  any  color  of  a  given  hue. 

Color  Brightness:  Colors  possessing 
identical  hue  and  saturation  may  still 
differ  in  brightness.  While  hue  and  satu- 
ration are  attributes  which  permit  the 
qualitative  determination  and  comparison 
of  colors,  brightness  is  a  comparative 
quantitative  characteristic   of  color,   giv- 


Since  Lindy  Put  His  Faith  in  the  "Spirit  of  St.  Louis." 


have 


been 


UK*  * 


For  over  22  years  we  have 
been  serving  the  men  who 
"put  on  the  show"  by  helping 
them  keep  it  on. 

When  you  think  of  equipment 
and  supplies  think  of  National 
. . .  we're  as  near  as  your  tele- 
phone ...  24  hours  a  day! 

"Everything 
for  the  Projection  Room" 

NATIONAL 

aamara»i'iijij 


ing  expression  to  how  a  color  affects  our 
sensation  as  being  more  or  less  bright. 

All  three  attributes — hue,  saturation 
and  brightness — are  to  be  thought  of  as 
purely  mental  phenomena  and  not  as 
physical  characteristics.  They  are  mental 
variables  related  to  the  variations  in  the 
physical  stimulus  caused  by  light  of 
changing  spectral  composition  entering 
the  eye. 

General  Comparison  of  Processes 

Numerous  methods  have  been  devised 
and  suggested,  using  either  the  additive 
or  subtractive  principle,  to  photographi- 
cally obtain  color  reproductions.  Of 
those  actually  in  use  at  present  for  mo- 
tion picture  production,  the  subtractive 
method  is  practically  favored  to  exclu- 
sion. 

The  additive  process,  while  much  sim- 
pler in  processing  and  less  complex  in 
the  synthesis  phase,  presents  two  obsta- 
cles which  have,  unfortunately,  pre- 
vented its  wider  adoption  for  practical 
use.  These  are  the  necessity  of  having 
to  use  auxiliary  optical  elements  in  pro- 
jection and  the  low  light  efficiency  in 
projecting  the  prints  through  filters  and 
superimposing  devices. 

The  comparative  shortcomings  of  the 
subtractive  processes  are  to  be  seen  in 
the  complexity  of  making  superimposed 
color  prints  and  in  the  fact  that  the 
complementary  dyes  required,  particu- 
larly cyan  and  magenta,  have  so  far  not 
been  produced  with  satisfactory  selec- 
tive transmission  characteristics. 

Looks  Forward  to  Standardization 

The  relentless  efforts  made  in  improv- 
ing and  simplifying  the  technique  of 
photographic  color  processes  for  motion 
picture  production  will,  no  doubt,  bring 
about  a  time  when  color  photography  is 
standardized  to  a  degre  comparable  with 
present  black-and-white  photography.  It 
offers,  however,  a  relatively  new  and  very 
large  field  to  any  progressive  cine  tech- 
nician in  the  study  of  its  psychophysical 
and  psychological  phases. 

It  is  well  conceivable  that  lack  of 
understanding  or  of  knowledge  of  psy- 
chophysical and  psychological  color  phe- 
nomena may  soon  be  recognized  as  a 
greater  source  of  reproductive  failures 
than  the  shortcomings  traceable  to  pure- 
ly physical  phases  of  the  specific  color 
process  used. 

We  see  that  color  as  a  science  has  a 
rather  complex  structure.  In  being  con- 
fronted with  a  complex  problem,  we  may 
either  react  to  it  by  throwing  up  our 
hands  and  turning  our  backs,  or  we  may 
become  fascinated.  Either  attitude  is 
understandable  and  justified  as  long  as 
one  has  his  choice.  It  would  seem  to  be 
the  course  of  wisdom,  however,  for  film 
technicians  to  be  fascinated. 


26 


INTERNATIONAL  PROJECTIONIST 


February  1949 


SMPE  PAPERS  ABSTRACTS 

I  Continued  from  page  16) 

picture  photography.  Five  types  of  light 
sources  might  be  used  for  this  work,  includ- 
ing incandescent  sources,  mercury  lamps, 
fluorescent  lamps,  flash  tubes,  as  well  as 
photoflash  lamps.  Also  explained  is  a  new 
type  of  fluorescent  lamp  developed  specific- 
ally for  high-speed  motion  picture  photog- 
raphy. 

ROTATING    PRISM    TYPE    CAMERA 

John  H.  Waddell 

Bell   Telephone  Laboratories 

A  rotating  prism  type  camera  is  one  used 
for  high-speed  photography  in  which  the 
image  is  refracted  by  parallel  plane  glass 
in  synchronism  with  continuously  moving 
film,  thus  avoiding  intermittent  operation 
and  lens  shutter  problems.  The  many  de- 
sign problems  necessary  to  produce  a  camera 
of  this  type  are  described,  explaining  the 
operation  of  the  Fastax  camera,  capable  of 
photographing  as  many  as  10,000  images 
per  second. 

NEW    ADVANCES    IN    X-RAY    MOVIES 

C.  M.  Slack,  L.  F.  Ehrke,  C.  T.  Zavales, 

D.  C.   Dickson 

Westinghouse  Electric   Corporation 

Equipment  has  been  developed  for  making 
X-ray  motion  pictures  within  exposure  times 
of  10  microseconds  and  at  frame  rates  from 
50. — 150  per  second.  The  extremely  short  ex- 
posure time  permits  the  radiographing  of 
very  rapidly  moving  objects  and  the  use  of 
continuously  moving  film  without  blur  in  a 
specially  constructed  camera  without  a  shut- 
ter. The  short  exposures  are  obtained  by 
pulsing  the  X-ray  tube  in  a  circuit  derived 
from    radar    technique. 

The  system  may  also  be  used  in  some 
cases  to  produce  an  image  on  a  fluorescent 
screen  which  may  be  photographed  on  mo- 
tion picture  film  with  a  camera  such  as  the 
General  Radio  oscilloscope  camera  or  a  syn- 
chronized motion  picture  camera. 

An  outgrowth  of  the  "Micronex"  tech- 
nique for  making  single  radiographs  with 
an  exposure  of  1  millionth  of  a  second,  the 
motion  picture  system  has  been  developed 
primarily  for  the  investigation  of  burning 
rocket  propellants.  It  is  expected  that  suit- 
able adaptations  may  be  made  for  a  number 
of    other   problems. 

HIGH-SPEED   PHOTOGRAPHY   IN   THE 

AUTOMOTIVE   INDUSTRY 

Richard  O.   Painter 

General    Motors   Proving   Ground 

The  methods  of  using  high-speed  pho- 
tography in  the  automotive  industry  are 
described,  together  with  application.  Among 
the  latter  are  door  latch  mechanisms,  safety 
glass  impact  tests,  shock  absorbers,  and  the 
deflections  of  a  tire  striking  an  obstacle. 
Great  savings  in  time  and  expense  in  devel- 
oping new  mechanisms  are  reported. 

PRODUCING   A   METALLIC   SALT   SOUND 

TRACK    ON    16-MM   ANSCO    COLOR    FILM 

J.  L.  Forrest 

Ansco 

In  16-mm  Ansco  color  motion  picture  film 


suri'irs 


w*--" 


SEALED 
HERMETICALLY 


,  ONE-PIECE 
MOUNT 


ANODIZED 
FINISH 


COATED 
'  OPTICS 


MM 


f/ 


&/* 


&&* 


&,. 


ARE  THE  LENS  ELEMENTS  COATED? 

Yes,  all  glass-to-air  surfaces  (all  surfaces  except 
the  cemented  ones)  are  coated  with  a  thin  film 
of  hard  magnesium  fluoride  on  Snaplite  Series 
II  and  Super-Snaplite  lenses. 

JUST  WHAT  DOES  THIS  COATING  DO? 

The  coating  decreases  internal  reflections  and 
increases  light  transmission  at  each  surface.  By 
practically  eliminating  stray  light,  it  improves 
contrast,  brings  out  colors  more  fully,  and  in- 
creases the  brightness  of  the  picture. 

HOW    MUCH    BRIGHTER    DOES    THE    LENS    COATING 

MAKE  THE  PICTURE? 

The  coating  increases  light  transmission  about 
4%  per  lens  surface.  Thus  the  Super-Snaplite 
having  8  coated  glass-to-air  surfaces  transmits 
about  30  %  more  light  than  would  a  similar  lens 
with  uncoated  elements. 

WHAT  CAUSES  COATED  LENSES  TO  BECOME  CLOUDY? 
The  magnesium  fluoride  coating  does  not  cause 
cloudiness,  but  might,  because  of  its  purple- 
straw  color,  make  the  cloudiness  more  appar- 
ent. Under  the  same  conditions- uncoated  lenses 
will  also  have  the  deposit. 

WHAT  IS  THE  DEPOSIT  THAT  FORMS  ON  LENS 

SURFACES? 

This  deposit  may  be  dust,  fumes  from 
lamp  housing  or  oil.  Poor  ventilation 
°1flW^^  t  V  \  of  the  projector  or  projection  room 
*«  *  L  v  \  will  probably  cause  a  deposit  to  form 
on  any  glass  surface  in  the  projector  or 
projection  room. 

"You  Get  the  Most  Uniform  Light  with  Super-Snaplite" 


KOLIiAlOlt<;i?N     / 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


© 

OKPOKATION 


INTERNATIONAL  PROJECTIONIST 


February  1949 


27 


the  silver  is  removed  from  the  image,  leav- 
ing dye  in  the  three  layers.  The  combina- 
tion (maximum  density)  of  the  subtractive 
colors — cyan,    magenta,    and    yellow — has    a 


If 044,  can  depend  on 


G-83 

*">Pere,  ArSo„  G 


Precision  designed,  ruggedly- 
constructed,  factory  "aged" 
and  thoroughly  tested  for 


SMOOTH  OPERATION 

CONSTANT    POWER   SUPPLY 

LONG   LIFE 


Guaranteed  fori  ,200  op- 
erating hours  when  used 
at  their  proper  rating. 


ASK   YOUR    DEALER 
—  HE   KNOWS 


GORDOS   CORPORATION 

86   SHIPMAN   STREET      •      NEWARK  2,  N.  J. 


visual  density  of  about  3,  which  is  sufficient 
lo  produce   good   screen  contrast. 

The  maximum  density,  while  being  visu- 
ally opaque,  has  a  transmission  band  in  the 
near  infra-red  in  the  region  of  8000  A.U., 
which  is  the  most  sensitive  region  of  the 
caesium  type  phototube.  While  for  many 
purposes  this  may  not  be  objectionable,  it 
can  be  overcome  by  differentially  processing 
the  film  so  that  the  sound  track  modulations 
are  opaque  to  red  light  without  affecting  the 
dye  picture   area. 

This  paper  describes  a  method  by  which 
differential  treatment  of  the  sound  track 
area  can  be  accomplished. 

HIGH-SPEED  TELEPHOTO  LENS 

F.   G.    Back 

Research   and   Development    Laboratory 

A  high-speed  telephoto  lens  F/1.3  for 
16-mm  and  8-mm  motion  picture  cameras 
has  been  developed.  The  lens  has  a  very 
high  resolution,  is  corrected  for  longitudinal 
and  transversal  color,  has  no  distortion  and 
practically  no  field  curvature.  Its  focal 
lengths   are  3%"   and   1%"  respectively. 

NEW  SERIES  OF  16-MM  CAMERA  LENSES 

Rudolph    Kingslake 

Eastman  Kodak  Company 

A  matched  series  of  six  high-grade  inter- 
changeable lenses  for  16-mm  motion  picture 
cameras  has  been  developed.  Focal  lengths 
range  from  15-mm  to  152-mm,  with  relative 
apertures  from  f/1.4  to  f/4.0,  respectively. 
Reasons  underlying  the  choice  of  formula 
for  each  lens  are  discussed. 

IMPROVED     SOUND    REDUCTION     PRINTER 

C.   W.   Clutz   and    J.   G.   Srreifferr 

Eastman  Kodak  Company 

While  retaining  the  basic  principles  of  the 
earlier    Eastman    sound    reduction    printers, 


HUJIIRD  UJllMER 


Flutter  Suppressor  Wins 
ACADEMY    AWARD! 

The  Academy  of  Motion  Picture  Arts  &  Sciences  recog- 
nized the  value  of  this  development  in  making  its  1947 
award  to  C.  C.  Davis  of  the  Western  Electric  Co. 

CENTURY  can  give  you  this  outstanding  improvement 
in  sound  reproduction   NOW. 


The  Award- 
winning  Hydro 
Flutter  Suppressor 
as  used  in  the 
new  Century 
sound  reproducer. 


Improve   the    perform- 
ance  quality   in    your    theatre  —  see 
'  your  dealer  or  write  for  information. 

CENTURY  PROJECTOR  CORP 

New  York,  N.  Y. 


Century  Sound  Reproducer 


this  new  model  incorporates  significant  im- 
provements such  as:  a  newly  designed  apo- 
chromatic  objective  system,  a  condenser 
system  of  increased  efficiency,  reduction  of 
film  wear  by  elimination  of  all  stationary 
members  in  the  film  path,  increased  film  ca- 
pacity, torque  motor  take-ups,  life-time  lu- 
brication of  most  bearings,  pedestal  mount- 
ing for  greater  convenience  of  operation,  and 
complete  operating  controls  conveniently 
located. 

CO-ORDINATION    OF   35-MM   AND    16-MM 

SOUND  -  REPRODUCING    CHARACTERISTICS 

John   K.   Hilliard 

Altec  Lansing  Corporation 

This  paper  outlines  how  the  35-mm  Stan- 
dard Theatre  Characteristic  was  arrived  at, 
and  how  a  derived  16-mm  characteristic 
should  be  obtained.  To  arrive  at  the  proper 
conclusion,  it  is  necessary  to  review  current 
recording  practices. 

PORTABLE  MAGNETIC  RECORDING  SYSTEM 

O.  B.  Gunby 

RCA    Victor   Division 

Progress  and  developments  in  synchronous 
magnetic  recording  are  described,  and  some 
of  the  basic  specifications  which  have  been 
adopted  are  given,  such  as  film  speed  of  90 
feet  per  minute  and  widths  of  recording, 
playback,  and  erase  heads.  An  earlier  port- 
able film  recorder  has  been  adapted  to  mag- 
netic operation,  permitting  operation  of  film 
recording  equipment  in  locations  formerly 
inaccessible  to  work  of  this  type. 

LOW-COST  16-MM  FILM  PROJECTOR 

Franz   G.   Talley 

Connecticut  Telephone  &  Electric  Company 

A  new  lightweight  16-mm  motion  picture 
projector  was  evolved  to  provide  quality  op- 
eration at  low  cost.  Among  the  design  feat- 
ures are  the  elimination  of  precision  toler- 
ances other  than  in  highly  critical  areas,  in- 
dividual unit  design  which  permits  assembly 
by  relatively  unskilled  operators,  and  re- 
duction of  the  overall  number  of  component 
parts.  Unit  construction  also  simplifies  the 
problem  of  repair.  A  demonstration  of 
SMPE  Test  Film  Z-522  was  presented  on 
this  projector. 

ADVANCES  IN  CADMIUM-MERCURY  LAMPS 

E.  W.  Beggs 

Westinghouse    Electric    Corp. 

The  short  arc  lamp  design  increases 
brightness  and  provides  a  compact  source 
of  light  for  both  spot  and  flood  operation  in 
one  simple  projector.  With  a  minimum  use 
of  filters,  a  cadmium-mercury  combination 
provides  color  correction  suitable  for  three- 
color  photography.  Mercury  vapor-discharge 
lamps  are  practical  for  projection  of  black- 
and-white  but  are  not  yet  suitable  for  color. 
Such  lamps,  however,  are  now  used  to  reduce 
heat  problems  in  television  production. 

Intermittent  gas  arcs  and  continuous  dis- 
charge through  krypton  gas  are  not  yet  com- 
mercially practical  for  studios.  The  high 
spectrum  quality  and  blue-white  color  of  the 
krypton  arc  is  held  to  justify  further  de- 
velopment. 


28 


INTERNATIONAL  PROJECTIONIST 


February  1949 


CONDENSERS  AND  COILS 

I  Continued  from  page  24) 

alter;  likewise,  a  given  combination  of 
inductance  and  capacity  will  oscillate 
only  at  one   frequency. 

Current  in  a  purely  inductive  circuit 
will  lag  one-quarter  (%)  of  a  cycle 
ahead  of  the  voltage.  The  reason  for 
this  is  that  an  uncharged  condenser  has 
no  impedance,  and,  therefore,  a  heavy 
initial  current  will  produce  no  voltage 
across  it.  When  the  condenser  is  fully 
charged  its  impedance  is  infinitely  great 
and  there  is  no  current  passing:  at  this 
stage    a    voltage    exists    across   it. 

A  condenser,  therefore,  just  upsets 
the  relationship  between  the  voltage  and 
current  in  an  a-c  circuit  as  much  as  a 
magnetic  coil  does,  only  where  one  delays 
the  current,  the  other  actually  advances 


MAX. 


NO 


CURRENT  J=  N0   CURRENT  =k  MAX. 


VOLTS 


'VOLTS 


FIG.  9. 


FIG.  10. 


it.  Figs.  9  and  10  show  that  when 
current  is  a  minimum  the  voltage  is  a 
maximum,  and  vice-versa. 

A  simple  series  circuit  embodying  a 
coil  and  condenser  is  shown  in  Fig.  11. 
This  is  known  as  an  acceptor  circuit. 
Here  the  current  existing  within  the  coil 
and  condenser  will  be  the  same.  How- 
ever, the  voltages  in  both  the  coil  and 
condenser  will  be  out  of  phase  with  the 
current — the  coil  volts  will  be  one-quarter 
(%)  of  a  cycle  ahead  of  the  current,  and 
the  condenser  volts  will  be  one-quarter 
(Vi)  of  a  cycle  late — therefore,  the  two 
are   diametrically   opposed. 

This  arrangement  is  used  in  radio 
receivers  and  may  be  tuned  to  accept 
a  certain  frequency  by  adjustment  of  the 
capacity  of  the  condenser. 

A  parallel  circuit  of  inductance  and 
capacity  is  shown  in  Fig.  12.  Here  a 
rather  different  state  of  affairs  exists,  for 
the  voltages  across  both  coils  must  be 
the  same :  therefore  any  out-of-phase  con- 
dition must  be  in  the  respective  currents 
in  the  coil  and  condenser.  This  is  a 
rejector  circuit,  and  can  be  tuned  to  a 
certain  frequency  just  like  the  acceptor 
arrangement;   but  whereas  the  acceptor 


passes  one  frequency  only,  the  rejector 
passes  all  others  and  rejects  the  tuned 
frequency. 

The  principles  of  acceptor  and  rejec- 
tor circuits  are  exceedingly  interesting, 
particularly  to  those  having  some  interest 
in  radio  communication.  Why  should 
one  circuit  offer  an  easy  path  to  one 
frequency,  rejecting  all  others,  while 
the  other  acts  as  a  high  impedance  to 
one  frequency  and  offers  little  opposition 
to  any  others? 

Well,  examining  Fig.  11,  a  simple 
acceptor  circuit,  we  see  that  since  any 
currents  intending  to  get  through  the 
arrangement  must  pass  through  both  coil 


and  condenser,  and  as  these  are  tuned  to 
one  frequency  only,  obviously  that  fre- 
quency alone  will  cause  the  coil  and 
condenser  to  oscillate  in  sympathy.  Any 
other  frequency  will  be  "off  the  beat,"  as 
it  were,  and  will  be  unable  to  force  its 
way  through. 

In  Fig.  12  the  rejector  circuit  operates 
quite  oppositely  in  every  way,  for  since 
alternative  paths  are  present — through 
either  the  coil  or  the  condenser — frequen- 
cies other  than  the  tuned  one  can  get 
through  all  right;  but  the  tuned  frequen- 
cies oscillate  inside  the  closed  circuit  and 
do  not  dissipate  themselves  across  the 
full  outer  circuit. 


THE  STRONG  TROUPER 


A.  C.  CARBON  ARC  SPOTLIGHT 


E&.? 


for  theatres,  auditoriums  and  night  clubs  where  the 
length  of  throw  does  not  exceed  100  feet, 


FIG.  11  FIG.  12. 

INTERNATIONAL  PROJECTIONIST     •     February  1949 


PRODUCING  A  SNOW  WHITE  uniformly  ilium-        from    any    alternating    current    110-volt    con- 
inated    spot,    crisp   on    the    edges,    the   Trouper        venience  outlet. 

will   supply   that  essential   sparkle   to   a    pres-        A    HIGHLY    EFFICIENT,    adjustable    and    self- 
entation    that   is   obtainable   only  with   the   use        regulating    transformer    which    is    an    integral 
of   high    intensity   arcs.                                                      part    0f    the    spotlight    base    reduces    the    110- 
FAR  SURPASSING  IN  BRILLIANCY  of  spot  any       volt   alternating   current   supply   to   a    low  arc 
incandescent    or    vertical    arc    type    spotlight,        voltage  and   for   the   first  time   makes   possible 
the   Trouper   will    actually   equal    many    of    the        a   high   intensity  arc  spotlight  without  the  use 
large    theatre    type   spotlights.                                        of   heavy    rotating   equipment. 
ENGINEERED  WITH  AN   EYE  toward  simplicity        THE    CARBONS    ARE     FED    AUTOMATICALLY 
and  ease  of  operation,  this  spotlight  is  capable        by   an    electric   motor   which    maintains   a    con- 
of  being  easily  operated   by  a  "new"   man   on        stant  arc  gap.   This   results  in  a  steady   light, 
"opening   night".                                                                 free  from  hiss  or  flicker. 

THE     OPTICAL     SYSTEM     utilizes     a     silvered        A   TRIM    OF   CARBON    consists   of   two   6mm   x 
glass  reflector  to  collect  the  illumination  from        7"  heavy  copper  coated   high  intensity  carbons 
the  source  and  direct  it  to  a  circular  aperture,        with   a    burning   time    of  one   hour   and    twenty 
from    where    it    is    projected    to    the    stage    by        minutes   at  21    volts  and   45   amperes  arc  cur- 
means  of  a  two  element  variable  focal   length        rent- 

lens  system.                                                                           A    HORIZONTAL  MASKING   CONTROL  can    be 
FOR  A  60-FOOT  LENGTH  OF  THROW,  the  size        angled    at   45    degrees    in    each    direction    from 
of  the  projected  spot  is  variable  from  a  mini-        horizontal. 

mum  of  30  inches  "head  spot"  to  a  maximum        THE   COLOR    BOOMERANG   contains   six    slides 
of  33  feet  "flood".                                                        and   an   ultraviolet  filter  holder. 
EXTREMELY  MODEST  IN   ITS   POWER  require-        MOUNTED  on  casters.  Easily  disassembled  into 
ments,    this    spotlight    draws    only    10    amperes        two   units  for  shipment. 

SOLD  BY  INDEPENDENT  THEATRE  SUPPLY  DEALERS. 
Use  the  coupon  to  obtain  further  details,  prices  and  name  of  your  nearest  dealer. 

THE 

STRONG 

ELECTRIC  CORP. 

"The  World's  Largest  Manu- 
facturer of  Projection 
Arc  Lamps" 

Please  send  free  literature,  prices  and  name  of  the 
nearest  dealer  in  Strong  Spotlights. 

NAME      

COMPANY         ...                                

1     14   CITY    PARK  AVE.   1 
R       TOLEDO   2,   OHIO      £ 

STREET                                                                             

CITY   and    STATE    

29 


LEONARD  S.  GREENBERGER 
— Manager  of  Fairmount  Theatre, 
Cleveland,  Ohio — says: 

"Our  regular  RCA  Service  has 
been  the  reason  behind  more 
than  six  years  of  trouble-free 
sound  reproduction." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


STABILITY  vs.  CHAOS  IN  Tv 

(Continued  from  page  18) 

niques  (such  as  special  forms  of  satel- 
lite or  peripheral  stations),  new  types  of 
transmitting  and  receiving  antennas,  new 
designs  of  receiver  components  and  as- 
semblies, and  careful  and  extensive  field 
tests. 

The  engineers  should  be  encouraged 
to  carry  forward  experimental  research 
along  such  lines.  But  this  does  not  mean 
that  their  ideas  should  be  accepted  until 
thoroughly  completed  and  field-tested. 
Nor  should  they  even  be  publicized  until 
that  point  of  definite  proof  of  their  use- 
fulness has  been  reached.  Above  all,  such 
untried  ideas  should  not  become  the  sub- 
ject of  long  and  sometimes  unhelpful 
hearings  in  Washington. 

Shun  Too  Easy  Acceptance 

Consider  what  might  happen  in  a  great 
hospital  if  every  new  drug  or  remedy 
which  was  brought  to  its  superintendent 
was  given  unlimited  publicity  and  was  at 


YOUR  ASSURANCE  OF  THE  BEST! 


WENZEL 
"Smooth-Running" 

PROJECTOR 

You  are  assured  of  "Smooth-Running" 
performance  with  the  Wenzel  time- 
proven  projector.  Use  Wenzel's  pre- 
cision replacement  parts  .  .  .  and  your 
present  equipment  will  do  a  smoother- 
running   job. 


WENZEL 
WD-9 

Film  Side 
Drum 
Cover 
Slip-in 
Type 

Assembly 


Write  for  our  NEW  complete  catalog  WC25. 
We  will  sell  only  through  Independent 
Theatre  Equipment  Dealers.  Mention  the 
dealer  serving  you. 


raifeifflEii^^M!^£N5i 


Manufactured  by 

HEYER-SHULTZ,  Inc. 


MONTCLAIR,  N.  J. 


ALL   METAL 

GUARANTEED  5  YEARS 


Distributed  Exclusively  by 


once  tried  on  all  available  and  unhappy 
patients.  Some  miraculous  cures  might 
occur;  on  the  other  hand,  the  neighbor- 
ing undertakers  would  undoubtedly  be 
overworked. 

Medical  men  properly  insist  on  long 
and  careful  clinical  tests  of  every  pro- 
posed remedy  before  it  is  approved  for 
general  practice.  Indeed,  publicity  by 
ethical  physicians,  dealing  with  new^  med- 
ical materials,  always  properly  empha- 
sizes the  experimental  nature  and  the  in- 
complete information  available  for  such 
material.  In  some  instances  it  has  been 
found  that  while  apparent  cures  could  be 
accomplished  by  some  remedies,  the  sec- 
ondary results  at  a  later  date  were  fatal. 

This  lesson  should  be  taken  to  heart  by 
all  who  are  involved  in  television  devel- 
opment —  engineers,  manufacturers, 
broadcasters,  governmental  officials,  and 
editors. 

It  is  easy  enough  to  make  startling  and 
sensational  proposals.  How  delightful 
it  would  be  to  use  1000-kilowatt  trans- 
mitters on  10,000  mc.  to  send  out  glorious 
three-dimensional,  high-detail,  color  pic- 
tures accompanied  by  three-dimensional 
sound.  How  delightful — and  how  utterly 
impracticable  and  premature! 

Suggests  a  Moratorium 

It  is  time  for  the  television  industry 
and  its  regulators  seriously  to  call  a  halt 
on  continuous  suggestions  for  untested 
changes.  Let  us  have  a  moratorium  on 
changes  every  few  months  on  the  basis 
of  a  bright  idea  which  has  not  been  thor- 
oughly worked  out  in  the  laboratory,  ade- 
quately tested  in  the  field,  searchingly 
investigated  as  to  its  likely  consequences, 
and  studied  as  to  its  economics.  Let  us 
benefit  from  the  English  decision  to  crys- 
tallize television  practices  for  a  number 
of  years. 

Let  us  take  to  heart  the  lesson  of  clini- 
cal tests,  as  practiced  in  medicine.  Medi- 
cine deals  with  the  life  and  death  of  in- 
dividuals. Television  engineers  deal  with 
the  success  or  failure  of  a  great  industry, 
and  of  the  service  to  the  public  which 
it  can  render. 

'Sound  Track' Compendium  Ready  Now 

Ready  now  is  "The  Sound  Track  Book  of 
the  Theatre,"  a  compendium  of  articles 
which  have  appeared  over  a  period  of  sev- 
eral years  in  the  magazine  of  the  same 
name  which  is  distributed  at  intervals  by 
Motiograph,  Inc.  The  volume — 6  x  9  inches, 
having  more  than  450  pages  and  300  illus- 
trations— constitutes  an  encyclopedia  of 
motion  picture  theatre  activity,  from  man- 
agement down  through  projection. 

The  articles  are  accurate  and  authorita- 
tive and  are  so  written  as  to  be  perfectly  in- 
telligible even  to  the  novice  in  theatre  work. 
The  technical  articles  covering  equipment 
and  technique  have  been  pointed  directly 
at  the  projectionist.  Priced  at  $10,  the  vol- 
ume is  available  from  "The  Sound  Track" 
at  1001  Washington  Blvd.,  Chicago,  7. 


30 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


NEW  MOTIOGRAPH-HALL  LAMP 

(Continued  from  page  19) 

power  fluctuations  occur,  the  control 
equipment  varies  the  arc  gap  for  opti- 
mum operation. 

The  moving  portions  of  the  M-H  lamp 
consist  of  comparatively  few  parts,  all 
of  which  are  precisely  machined  and 
extremely  wear-resistant.  The  arc  burner 
mechanism  is  of  unit  construction,  per- 
mitting quick  and  easy  removal  if  serv- 
icing be  required.  The  housing  is  roomy, 
well  ventilated  and  has  a  false  bottom 
for  the  entire  length  of  the  burner 
mechanism  to  facilitate  cleaning. 

Close  Attention  to  Details 

Positive  carbon  contacts  are  made  of 
bronze,  which  has  the  best  heat  conduc- 
tivity consistent  with  resistance  to  oxida- 
tion and  scaling.  The  contact  surfaces 
are  lined  with  pure  silver  l/16th  inch 
thick.  These  materials  readily  conduct 
current  and  carry  away  the  heat,  yet 
they  will  not  scale. 

No  ammeter  is  included  on  the  M-H 
lamp,  Motiograph  holding  to  the  theory 
that  electrical  current  indicating  instru- 
ments are  so  delicate  as  to  have  their 
accuracy  impaired  by  continued  exposure 
to  high  temperatures,  vibration  and 
strong  magnetic  currents.  It  is  suggested 
that  the  best  location  for  such  instru- 
ments is  on  the  front  wall  of  the  projec- 
tion room. 

More  detailed  information  anent  this 
new  M-H  lamp  is  through  any  Motio- 
graph dealer  or  by  writing  direct  to  the 
factory. 

IP  TELECASTS 

(Continued  from  page  25) 

Tv  outlets  in  San  Francisco,  Detroit  and 
Boston,  and  the  latter's  bid  for  stations 
in  Cleveland  and  Cincinnati.  Paramount 
will  appeal  the  decision. 

Recent  survey  by  Audience  Research 
shows  that  movie  attendance  of  Tv  set 
owners  is  25%  below  that  of  non-owners. 
On  day  before  interview  69%  of  set  own- 
ers watched  Tv,  while  8%  of  non-owners 
did  likewise  in  someone  else's  home  or  in 
public  places.  In  response  to  query  "Do 
you  attend  the  movies  less  frequently 
than  before  you  had  a  Tv  set?"  the 
results  were  as  follows:  less  frequently, 
53%;  about  the  same,  46%;  more  fre- 
quently, 1%. 

Tv,  radio  and  even  newspapers  have 
scooped  the  newsreels  so  consistently  as 
to  occasion  a  drastic  cut  in  newsreel 
theatre  receipts.  Trans-Lux  Theatres, 
reporting  a  50%  decline  at  the  box-office 
of  two  theatres,  and  at  least  a  20%  drop 
in  all  others,  recently  switched  several 
houses  to  feature-film  showings.  Decision 
on  remaining  newsreel  spots  will  be  forth- 
coming shortly. 

Philadelphia  on  Jan.  1  started  collect- 


ing a  5%  tax  on  the  gross  receipts  of 
taverns  having  Tv  receivers.  The  move 
followed  litigation  by  which  the  State 
Liquor  Control  established  its  right  to 
require  bars  with  Tv  to  obtain  amusement 
permits.  .  .  .  Paramount's  KTLA  Tv 
outlet  in  Los  Angeles  will  inaugurate  a 
tele-transcription  service  for  theatres  and 
other  Tv  stations  on  the  West  Coast,  be- 
ginning Jan.  15.  System  will  be  a  dupli- 
cate of  the  one  now  in  use  at  Paramount 


Theatre,   N.   Y.   City.     Similar  setup  is 
planned  for  Par's  Chicago  outlet. 

The  Home  of  Swat  and  Slug,  Madison 
Square  Garden  in  N.  Y.,  delivered  a  body 
blow  to  those  exponents  of  the  "grega- 
rious" theory  with  respect  to  Tv  when  it 
announced  serious  consideration  of  aban- 
doning its  Tv  contracts  when  they  expire 
next  May  31.  The  Garden  figures  Tv  is 
sloughing  its  box-office.  Tv-theatre  mar- 
riage brokers  please  note. 


St&i  frenfrn*K<z*ice   with  STAR  CORE 


STAR  CORE,  exclusive  feature  with  the 
Lorraine  Carbons  —  a  manufacturing 
process  that  increases  the  performance 
of  the  carbons. 

A  more  brilliant,  steadier,  more  con- 
sistent white  light — more  economically 
. . .  proven  facts  as  shown  by  tests 
made  under  actually  operating  con- 
ditions. 


oine  Corbons  ore  world  renowned  .  .  . 
lorgest  theatres  in  the  U.  S.  and 
ughout  the  world  uie  Lorraine  Carbons. 


WHITE    fOrt    DISTRIBUTION    DATA 

CARBONS,  INC. 

BOONTON,   N.J. 
NEW  YORK:  234  WEST  44in  STREET 


t*A 


WITH   ANY 


LAMP 


IN  ANY  SIZE     THEATRE 


ANSWER 
TO  YOUR 
TECHNICAL 
PROBLEMS . 


■  ■ 


The  Altec 
Service  Man  and 
the  organization 
behind  him 


161  Sixth  Avenue, 
New  York  13,  N.  Y. 

PROTECTING  THE  THEATRE— FIRST  PLACE  IN  ENTERTAINMENT 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


31 


IA     ELECTIONS 

LOCAL   163,   LOUISVILLE,   KY. 

Chester  Demaree,  pres.;  Clarence  Young, 
vice-pres.;  John  P.  Flaherty,  bus.  rep.;  Wm. 
Fane,  Jr.,  rec.-sec;  Ed.  Williams,  fin.-sec. 

LOCAL   182,   BOSTON,  MASS. 

Joe  Nuzzolo,  Sr.,  pres.;  Morris  A.  Gold- 
man, vice-pres.;  Walter  F.  Diehl,  bus.  rep.; 
Joseph  Caplan,  treas.;  Leon  A.  Narbut,  fin.- 
sec;  Bernard  J.  Lynch,  rec.-sec;  Jack 
Rosenberg,  trustee;  Harold  Armistead, 
Harold  Kaitz,  James  Gibbons,  exec  board; 


F.  E.  McCLELLAN  — President, 
Ideal  Amusement  Company,  Johns- 
town, Pa. — says: 

"RCA  Service  has  been  our 

Silent  Partner  over  the  years, 

in    carrying   on    the    slogan, 

'The  Show  Must  Go  On.'" 

To  get  the  benefits  of  RCA  Service 

—write:  RCA  SERVICE  COMPANY, 

INC.,  Radio  Corporation  of  America, 

Camden,  New  Jersey. 


Wm.  C.  Dwyer,  Geo.  W.  Hookailo,  Al  J. 
Reith,  Jr.,  Ben  Beardman,  and  Joseph 
Cohan,  sen.   board. 

LOCAL   183,   BEAUMONT,  TEX. 

J.  D.  Southwell,  pres.;  P.  P.  Finnigan, 
vice-pres.;  J.  H.  Fehl,  bus.  rep.  and  sec- 
treas.;   W.  N.  Scarborough,  rec.-sec 

LOCAL    186,   SPRINGFIELD,   MASS. 

Edward  J.  O'Connor,  Jr.,  pres.;  John  F. 
Gatelee,  Jr.,  vice-pres.;  Louis  L.  Williamson, 
bus.  rep.;  Arthur  J.  Payette,  sec-treas.; 
Joseph  C.  Rodriguez,  sgt.-at-arms;  Granville. 
G.  Best,  Herbert  Binjis,  Edward  Whittle, 
exec,    board. 

LOCAL  223,  PROVIDENCE,  R.  I. 

Edwin  W.  Anthony,  pres.;  Fred  Coates, 
vice-pres.;  Herbert  F.  Slater,  Sr.,  bus.  rep.; 
Sydney  T.  Clarke,  sec;  Harvey  B.  Slater, 
fin.  sec-treas. ;  Arthur  R.  Jackson,  Chester 
A.  Pierce,  Chas.  L.  McKenna,  Sr.,  James 
W.  L.  Bowry,  Earl  E.  Madden,  Sr.,  exec 
board;  Herbert  F.  Slater,  Sr.,  and  Sydney 
T.  Clarke,  del.  I A  Convention;  Herbert  F. 
Slater,  Sr.,  Sydney  T.  Clarke,  del.  Rhode 
Island  AF  of  L  Convention;  Edwin  W.  An- 
thony, Sydney  T.  Oarke.  Herbert  F.  Slater, 
Sr.,  del.  Central  Federated  Union;  Fred 
Coates,  Harvey  B.  Slater,  alternates. 

LOCAL  228,   TOLEDO,   OHIO 

Ralph  Cobourn,  pres.;  Earl  Frank,  vice- 
pres.;  Harold  Plumadore,  bus.  rep.;  C.  B. 
Koch,  fin.-sec;  H.  L.  Neuert,  rec.-sec;  V.  E. 
Hostetter,  cor. -sec;  B.  F.  Holmes,  treas.;  C. 
L.  Welsh,  sgt.-at-arms;  C.  W.  Laycock,  Day- 
ton Canfield,  Leon  Lonis,  exec  board;  Harold 
Sheats,  K.  P.  Harrick,  Bert  Mulinix,  trustees. 

LOCAL  236,   BIRMINGHAM,  ALA. 

J.  C.  Harper  Sr.,  pres.;  J.  C.  Harper,  Jr., 
vice-pres.;  Ralph  A.  Root,  Sr.,  bus.  rep.;  J. 
Frank  Mankin,  sec;  C.  M.  Trent,  treas.; 
Fred  Pinkard,  sgt.-at-arms;  J.  W.  Tate,  trus- 
tee chairman. 


LOCAL  249,   DALLAS,  TEX. 

Paul  W.  Humphries,  pres.;  Curtis  Moore, 
vice-pres.;  Harvey  D.  Hill,  Sr.,  bus.  rep.; 
Wm.  R.  Estes,  Jr.,  fin.-sec;  Harvey  D.  Hill, 
Jr.,  rec.-sec;  D.  P.  Holt,  treas.;  James 
Blaydes,  sgt.-at-arms;  C.  L.  Borgeson,  Earl 
Ballard,  E.  P.  Medlin,  Jr.,  trustees;  Charles 
Harcum,  C.  C.  Holt,  exec,  board. 

LOCAL  253,  ROCHESTER,  N.  Y. 

Louis  Levin,  pres.;  L.  M.  Clark,  vice- 
pres.;  Fred  Boekhout,  bus.  rep.;  Floyd  B. 
Spencer,  sec;   Leon  E.  Burton,  treas. 

LOCAL   307,    PHILADELPHIA,   PENNA. 

Harry  J.  Abbott,  pres.;  Abbott  Oliver, 
vice-pres.;  Horace  B.  Johns,  bus.  rep.;  Jo- 
seph Abrams,  cor. -sec;  C.  Humphries,  rec.- 
sec;  Abe  Freeman,  Ben  Green,  exec,  board. 

LOCAL  386,  COLUMBUS,  OHIO 

Robert  W.  Greer,  pres.;  Everett  E.  James, 
vice-pres.;  Ned  R.  Welch,  bus.  rep.;  William 
Weltz,  rec.-sec;  Chester  Warner,  fin.-sec; 
Donald  Gardner,  sec-treas. 

LOCAL  407,  SAN  ANTONIO,  TEX. 

Gordon  H.  Dyer,  pres.;  Joe  P.  Cuevas, 
vice-pres.;  Wm.  B.  Keeler,  bus.  rep.;  Dan  G. 
Quinones,  rec.-sec;  Albert  P.  Slavin,  sec- 
treas. 

LOCAL  444,  NEW  KENSINGTON,  PENNA. 

P.  (Blackie)  Bordonaro,  pres.;  Walter 
Austin,  vice-pres.;  J.  J.  McCloskey,  bus. 
rep.;    F.    P.    (Reel)    McCoy,    sec;    Charles 


(SUCCESSOR  TO  FILM   CEMENT) 

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Applied  freely  to  film 
ends,  FILM-WELD  dis- 
solves film — fuses  it  into 
one  lasting  piece.  Easy  to 
use  for  hand  or  machine  splicing.  Re- 
tains its  strength! 

Use  FILM- WELD  to  patch  ALL 
types  and  makes  of  film — 8-mm, 
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Available  in  1  and  8  oz.  bottles  and 
16  oz.  cans.  Follow  the  lead  of  pro- 
jectionists in  countless  theaters  who 
are  already  PERMANENTLY  patch- 
ing film  with  FILM-WELD. 

Projectionists  favorites  also  are 
ZIPPER  CHANGEOVERS  to  guaran- 
tee continuous  performance;  Strong 
Universal  Rewind  Mules,  the  fool- 
proof "mule"  that  fits  any  enclosed 
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PROJECTOR    PARTS 


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Once  you've  used  them,  you'll  agree  that  the  built-in  preci- 
sion and  trouble  free  performance  of  La  Vezzi  parts  do  much  to 
hasten  repair  jobs  and  help  you  to  the  better  projection  that 
delights  patrons.  Specify  La  Vezzi  SUPER-SERVICE  Parts  for 
all  your  replacements!  Your  Theatre  Supply  Dealer  has  them. 


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32 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


Wolfe,  treas.;  A.  Haraznok,  sgt.-at-arms ;  J. 
Mickelic,  B.  Wosachlo,  H.  Wolfe,  trustees. 

LOCAL  451,   NEW  CASTLE,  PENNA. 

Jos.  J.  Carson,  pres.;  Tom  E.  Roberts, 
vice-pres.;  John  P.  Brogan,  bus.  rep.;  W.  J. 
McCormiek,  rec.-sec;  W.  F.  Hall,  fin.-sec. 

LOCAL  482,  CHAMPAIGN  &  URBANA,  ILL. 
D.  G.  Miller,  pres.;  A.  W.  Bothfuhr,  vice- 
pres.;  J.  C.  Crannell,  bus.  rep.;  G.  Myers, 
rec.-sec;  F.  B.  Spruth,  fin.-sec;  D.  Mellin- 
ger,  sgt.-at-arms;  J.  P.  Johnson,  trustee;  R. 
Dalhaus,  exec,  board;  D.  G.  Miller,  R.  Dal- 
haus,  J.   Daugherty,   exam,   board. 

LOCAL  666,  CHICAGO,  ILL.   (Cameramen) 

J.  Bertel,  pres.;  H.  Burch,  1st  vice-pres.; 
Walter  Hotz,  2nd  vice-pres.;  Bill  Strafford, 
bus.  rep.;  Jack  Leib,  fin.-sec;  Marvin  Spoor, 
treas.;  Jack  La  Fleuer,  Oscar  Ahbe,  trustees. 

LOCAL  730,   BARSTOW,  CALIF. 

John  0.  Jones,  pres.;  Harold  W.  Rosen- 
burg,  vice-pres.;  Harry  K.  Beauford,  bus. 
rep.;  Rudy  Trotter,  sec-treas.;  Wm.  T. 
Deck,   sgt.-at-arms. 


PERSONNEL 

Clyde  R.  Keith,  New  York  engineering 
representative  for  the  Erpi  division  of  West- 
ern Electric,  has  just  concluded  a  tour  of 
the  studio  sound  recording  departments  in 
Hollywood  and  has  returned  East. 

Henry  M.  Fisher,  until  recently  manager 
of  DeVry  Corp.'s  New  York  division,  as 
well  as  the  firm's  liaison  representative  in 
Washington,  has  been  named  vice-president 
in  charge  of  sales  and  merchandising  with 
headquarters  in  Chicago. 

With  DeVry  for  more  than  20  years, 
Fisher   has   had   wide    experience   in    engi- 


ATLANTIC  CITY'S 
HOTEL  of  DISTINCTION 

Devoted  to  the  wishes  of  a  discriminating 
clientele  and  catering  to  their  every  want  and 
embracing  all  the  advantages  of  a  delightful 
boardwalk   hotel. 

Spacious  Colorful  Lounges — Sun  Tan  Decks 
atop — Open  and  inclosed  Solaria — Salt  Water 
Baths  in  rooms — Garage  on  premises.  Courteous 
atmosphere   throughout. 


When  in  Atlantic  City  visit  the 

FAMOUS   FIESTA  LOUNGE 

RENOWNED  FOR  FINE  FOOD 


OPEN  ALL  YEAR 

Under  Ownership  Management 

Exclusive   Penna.  Ave.  and  Boardwalk 


neering,  sales  and  distribution  activities  in 
the  theatrical,  educational,  industrial,  re- 
ligious and  home  movie  fields. 

Ampro  Corp.,  of  Chicago,  has  announced 
two  promotions  of  key  men:  Howard  Marx 
has  been  upped  from  assistant  sales  man- 
ager to  vice-president  and  general  sales  man- 
ager. Frank  B.  Rogers,  Jr.,  eastern  divi- 
sion manager,  has  also  been  named  a  vice- 
president  and  assistant  sales  manager. 

Both  men  have  had  extensive  experience 
in  all  phases  of  the  audio-visual  field  and 
have  compiled  imposing  performance  records. 

Bertel  K.  W.  Budtz,  46,  southeastern 
Caribbean  manager  for  Western  Electric, 
died  suddenly  of  a  thrombosis  on  December 
14  at  his  home  in  Port-of-Spain,  Trinidad. 
He  had  just  returned  from  the  managers 
conference  sponsored  by  Westrex  Corp.  in 
New  York  last  November. 

H.  B.  (Bob)  Engel,  one  of  the  most  popu- 
lar and  widely  known  men  in  the  motion 
picture  equipment  field,  has  been  appointed 
general  sales  manager  for  GoldE  Mfg.  Co., 
of  Chicago.  For  more  than  30  years  Engel 
has  been  associated  with  the  theatre  field,  his 
most  recent  post  being  general  sales  man- 
ager for  DeVry  Corp. 

J.  H.  McNabb,  61,  since  1922  president  of 
Bell  &  Howell  Co.  of  Chicago,  died  on  Jan.  5. 
McNabb  was  given  much  of  the  credit  for  the 
expansion  of  B.  &  H.  business  through  the 
years  to  the  present  figure  of  $22  millions 
annually. 

Dr.  A.  H.  Pfund,  69,  Professor  Emeritus 
of  Physics  at  Johns  Hopkins  University,  died 
on  Jan.  6.  Noted  for  his  work  with  light, 
Dr.  Pfund  developed  an  instrument  which 
measured  the  heat  of  a  candle  18  miles  away, 
and  he  also  discovered  a  foolproof  method 
of  testing  precious  stones  through  their  infra- 
red reflections.  He  was  credited  with  devel- 
oping the  "gold-colored  glasses,"  which  are 
transparent  yet  eliminate  heat  and  glare 
from  light  and  are  used  mostly  by  people 
working  near  furnaces.  He  was  a  former 
president  of  the  American   Optical   Society. 

L.  W.  Teecarden  has  been  named  vice 
president  of  the  RCA  Victor  Division  of 
RCA  in  charge  of  all  technical  products, 
including  theatre  motion  picture  equipment. 

Thomas   L.   McCleary,   salesman   in   the 


Theatre  Equipment  Sales  Section  of  RCA 
in  the  Cleveland  territory,  has  gained  the 
Annual  Award  of  Merit  given  by  RCA  for 
conspicuous  effort. 

A.  G.  Berc,  field  service  engineer  for  RCA 
Service  Co.  for  the  past  five  years,  has  been 
named  regional  16-mm  sales  representative 
in  the  Dallas  area  with  offices  at  1907  Mc- 
Kinney  Ave. 

Orest  J.  Forest,  has  been  appointed  man- 
ager of  the  Trinidad  branch  of  Western 
Electric  Co.  (Caribbean),  replacing  the  late 
Bertel  K.  Budtz.  Climatic  changes  evi- 
dently affect  Forest  not  at  all,  for  he  re- 
ceived his  E.E.  degree  at  Harbin  Polytech- 
nical  Institute  in   Manchuria. 


Fifty  years  ago  Kodak  had  only  one  type 
of  negative  plate  and  one  type  of  photo- 
graphic paper — which  was  printed  by  sun- 
light. Today  the  company  produces  more 
than  75  types  of  film  support  coated  with 
200  kinds  of  light-sensitive  emulsions. 
Photographic  chemicals  go  out  in  430  differ- 
ent packages,  while  sensitized  paper  is 
shipped  in  20,000  varieties  of  packages. 


GIDNE Y  T ALLEY— President  and 
General  Manager,  Talley  Enter- 
prises, Inc.,  San  Antonio,  Texas — 
declares: 

"Thirteen  years  of  freedom 
from  sound  worries  has  prov- 
en that  RCA  Sound  Service 
and  Maintenance  is  defi- 
nitely a  sound  investment." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


CLAYTON  BALL-BEARING 

EVEN  TENSION  TAKE-UPS 

For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reels. 
Silent  Chain  Drives 

THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reels. 

CLAYTON    PRODUCTS    CO. 

31-45  Tibbett  Avenue  New  York  63,  N.  Y. 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


33 


Presenting:  David  E.  Day,  Chicago  Local  110 


NOT  many  of  today's  active  projec- 
tionists remember  a  projection  setup 
which  utilized  50-mm  film  (2  inches 
wide)  and  limelight,  nor  the  epochal 
Edison  film  "The  Great  Train  Robbery." 
Yet  that  was  the  combination  that 
launched  David  E.  Day,  member  of  Chi- 
cago Local  110,  on  the  show  business 
trail.  In  1906  Davy  worked  in  the  first 
nickelodeon  in  Chicago's  Loop,  where 
the  famous  Palmer  House  stands  today. 
Envisaging  big — but  big — things,  Davy 
once  signed  on  as  a  cameraman  to  shoot 
pictures  of  the  Miller  Brothers  101 
Ranch  rodeo  in  Oklahoma.    After  shoot- 


Davy 
Day 


ing  8,000  feet  of  film  the  party  returned 
in  high  spirits  to  the  lab  in  Chicago. 
But  no  pictures.  Someone  had  left  a 
ccp  over  the  lens !  "Fired"  was  the  word 
for  Davy. 

Followed  various  theatre  projection 
chores,  not  all  of  which  were  routine. 
For  example,  there  was  the  White  City 
setup  where  the  booth  (and  we  mean 
booth)  was  directly  over  the  ticket  cage. 
One  day  Davy  was  suddenly  precipitated 
into  the  cashier's  lap.  Nobody  believed 
his  denial  of  having  weakened  the  booth's 
supporting  beams  in  the  dead  of  the 
preceding  night. 

Old-timers  will  remember  the  pen- 
chant of  ye  olden  projectionist  to  crane 
his  neck  out  of  the  extremely  narrow 
portholes  which  then  were  in  vogue. 
Well,  they  can  relish  the  mental  picture 
of  Davy  Day  getting  his  head  out  just 
a  bit  too  far  in  one  of  these  slits  and 
having  to  wait  patiently  in  that  position 
until  the  manager  could  arrange  to  have 
the  framework  cut  away  and  thus  re- 
lease the  impetuous  rubberneck.  Davy 
v/as  really  giving  a  show  that  day — in 
competition  with  the  screen  image. 

Most  projection  mugs  have  a  hobby 
or  two  tucked  away,  some  of  them  sur- 

Photos  at  Supersonic  Speeds 

New  high-speed  photographic  equipment 
for  catching  the  image  of  objects  moving 
faster  than  sound  has  been  developed  by 
G.  E.  A  flash  of  light,  lasting  only  two- 
millionths  of  a  second,  throws  enough  bright 
light  on  exceedingly  quick  action  to  take 
photos  showing  virtually  no  motion. 

With  this  equipment  it  was  possible  to 
photograph  a  naval  shell  in  flight  at  1,842 
miles  per  hour — well  over  twice  the  speed 
of  sound!  The  shell  set  off  the  flash  and 
took  its  own  picture  by  cutting  between  a 
beam  of  light  and  a  photocell. 


reptitiously.  Davy  makes  no  secret  of 
his,  however,  particularly  when  in  1933 
he  built  an  amateur  radio  station  and  con- 
tacted many  projectionists  through  sta- 
tions W9PEH  and  W9TIC.  The  guy 
must  have  something  mechanically,  be- 
cause he  is  the  inventor,  but  the  very 
first,  of  a  plastic  coin  holder. 

Latterly,  Davy  has  turned  nusmismatist 
(coin  collector  to  you)  and  he  reports 
that  the  hobby  is  both  fascinating  and 
profitable.  Sort  of  a  being-paid-for-fun 
setup. 

A  charter  member  of  Local  110  and 
an  officer  for  more  than  20  years  therein, 
Davy  has  worked  at  the  Commercial 
Theatre  for  the  past  28  years.  He  now 
feels  that  he  has  contributed  substan- 
tially both  to  his  Local  and  to  his  job, 
so  now  he  hies  himself  away  to  Florida 
from  Nov.  15  to  May  1  each  year. 

Pretty  soft  may  say  thee;  but  when  a 
guy  has  slugged  it  out  all  along  the  line 
since  1906,  there's  nothing  to  be  had 
anywhere,  including  Florida,  that  he 
hasn't  earned  the  hard  way.  Davy  says 
that  his  experiences  in  the  craft  must 
shape  up  as  a  sort  of  taffy  by  comparison 
with  those  of  other  old-timers,  and  he 
would  like  to  hear  from  this  gang. 

Improvements  in  Transverters  Are 
Announced   by   Hertner 

Improvements  have  been  effected  in  several 
models  of  Transverter  motor  generator  sets 
manufactured  by  The  Hertner  Electric  Co. 
Design  changes  have  markedly  improved  the 
appearance,  as  may  be  seen  by  the  accom- 
panying photo,  with  streamlining  having 
been    achieved   through    the    use    of   a   new 


Hertner  Transverter  Type  HI  70-140. 

commutator  cover  and  an  aluminum  alloy 
motor   frame   design. 

New  model  Transverters  utilize  "sealed- 
for-life"  ball  bearings  which  obviate  the 
necessity  for  periodic  greasing  with  the 
consequent  danger  of  over-greasing.  This 
feature  will,  among  other  things,  eliminate 
the  danger  of  grease  getting  onto  the  com- 
mutator and  causing  grooving  and  other 
difficulties.  A  new  larger  conduit  box  for 
the  generator  has  been  made  standard  to 
provide  more  space  for  making  the  electrical 
connections. 

Full  details  relative  to  all  Transverter 
models  are  available  from  Hertner  at  12,690 
Elmwood  Ave.,  N.  W.,  Cleveland  11,  Ohio. 


Silver  Alloy  Magnets'  Longer  'Reach' 

From  a  new  silver  alloy  magnets  are  made 
which  have  a  much  longer  "reach"  than  the 
kind  that  boys  play  with.  This  means  that 
the  same  amount  of  "magnetic  work"  can 
be  done  with  smaller  magnets.  They  are 
also  permanently  magnetized  and  do  not  lose 
that  "reach"  as  the  years  roll  by. 

For  this  reason  tens  of  thousands  of  bits 
of  silver  fly  the  skies  in  airplane  instrument 
boards,  where  space-saving  is  important  and 
precise  performance  is  necessary  for  safety. 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you  ?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

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34 


INTERNATIONAL  PROJECTIONIST     •     February  1949 


SO  MUCH 


for  so  LITTLE 


$Q.OO 


3 


per  copy 
pottage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  1.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


S&nct  #da  it  Tlowl 


(Do  Tbt  (Delay 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18.  N.  Y. 

Gentlemen:  Enclosed  find  53.00  for  a   copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 

Name  

Address    


City 


State 


THEATRES 


PROJECTION  AND  SOUND  SYSTEMS 


MANUFACTURED    BY    INTERNATIONAL    PROJECTOR    CORPORATION    •    BLOOMFIELD,    NEW   JERSEY 


o 


fjft 


«>* 


tea  .,  r»  ' 


HI 


*.J*#''*^  ■ 


K 


v"b$£ 


W 


ss? 


^sss 


MARCH 


1  94  9 


¥ 


VOLUME  24       •       NUMBER   3 


30c  A   COPY    .    $2.50  A  YEAR 


***>* 


v&S*, 


GOO&b? 


or 


Mestf 


WHICH  WILL  YOU  HAVE 


For  some  reason,  the  goose  egg  stands  for 
zero  .  .  .  nothing. 

The  nest  egg,  however,  stands  for  a  tidy  sum 
of  money,  set  aside  for  your  own  or  your 
children's  future. 

It's  hardly  necessary  to  ask  you  which  you'd 
prefer. 

But  it  is  necessary  to  ask  yourself  what  you 
are  doing  to  make  sure  you  don't  end  up  with 
a  goose  egg  instead  of  a  nest  egg  ten  years 
from  now. 

The  simple,  easy,  and  obvious  thing  to  do  is 
to  buy  U.  S.  Savings  Bonds. 

Buy  them  regularly,  automatically,  on  a 


plan  that  pays  for  them  out  of  the  month-to- 
month  income  you  make  today. 

Millions  of  Americans  have  adopted  this 
practically  painless  way  to  save  up  a  nice  nest 
egg  for  the  needs  and  wants  of  the  future. 

In  10  years  they  get  back  $40  for  every  $3© 
invested  in  U.  S.  Savings  Bonds— bonds  as 
safe  and  solid  as  the  Statue  of  Liberty. 

There's  a  special  Savings  Bond  Plan  for  ym. 
Ask  your  employer  or  banker  about  it  today 
.  .  .   and  get  started  now. 

You'll  soon  realize  that  buying  U.  S.  Savings 
Bonds  regularly  is  one  of  the  most  important 
and  comforting  things  you  ever  did ! 


/totomatfc  sawig  is  $m  sai/ing  -  U>$-  Smnp  Bonds 

Contributed  by  this  magazine  in  co-operation  with  the  Magazine  Publishers  of  America  as  a  public  service. 


MAR  28 J949- 

<£>C1B    184791 


Western  Electric's  "300"  Recording  System 
Gefs  Rugged  Workout  in  Venezuela 


.faced  with  the  problem  of  mak- 
ing films  on  location  in  the 
mountainous  terrain  of  Vene- 
zuela, The  Princeton  Film  Center, 
Princeton,  N.  J.,  is  using  a  Type 
300  Recording  System  mounted 
in  a  small  truck. 

Gordon  Knox,  Executive  Direc- 
tor of  The  Princeton  Film  Center, 
says  "we  have  given  the  '300' 
System  a  rugged  workout  in 
Venezuela  and  it  has  performed 
faultlessly." 

W'herever  Western  Electric 
recording  equipment  is  used,  it 
has  earned  an  unequalled  repu- 
tation for  ruggedness,  versatility 
and  high  quality.  The  "300"  Sys- 
tem is  an  honored  member  of  the 
line  which  includes  the  Deluxe 
"400"  System  and  the  smaller 
"200"  Newsreel  System.  Write 
today  for  full  information. 


The  Princeton  Film  Center  recordist  at  the  mixer  of  the  "300" 
System    on    location    high    in    the    Venezuelan    mountains. 


This  small  truck  contains  the  complete  "300" 
Recording  System,  plus  all  the  power 
generating  equipment  needed  on  location. 


Electrical  Research  Products  Division 

OF 

Western  Electric  Company 

INCORPORATED  *  J 

120  BROADWAY,  NEW  YORK  5,  N.Y. 

Hollywood    office  —  6601    Romaine   St. 


foot 


of/0 


choose 


MAGNART 


TRADE     MARK    REG. 


1-KW  TO  70  AMPS 

The  "1-KW"  Special  is  a  man-sized  lamp  priced  to  meet  "Pee-wee"  lamp 
competition.  .  .  .  May  be  converted  to  use  upward  to  70  amps  at  any  time. 
.  .  .  Employs  the  largest  reflector  used  for  1  -KW  service.  ...  By  far,  the 
greatest  dollar  value  in   lamps. 

The  New  Magnarc  De  Luxe  is  supreme  in  its  field  at  any  amperage,  between 
40  to  70.  .  .  .  Produces  10%  higher  screen  illumination.  .  .  .  The  highest 
ratio  of  screen  lumens  per  arc  watt.  ...  At  70  amperes,  with  a  projector  hav- 
ing and  efficient  DISC  type  revolving  shutter,  it  develops  the  maximum  light 
that  can  be  used  without  a  heat  filter.  .  .  .  Operating  costs  under  these  con- 
ditions, are  far  below  that  of  85  ampere   lamps.  .  .  . 

Magnarc  Lamps  assure  80%,  NOT  60%,  side-to-center  screen  light  distribu- 
tion. .  .  .  They  are  the  first  choice  and  preferred  lamp  of  large  or  small  Drive-ins 
and   all   theatres. 


1  1 


FIRST    WITH    THE    FINEST 


TRADE     MARK    REG. 


120-180  AMPERES 


This  modern  lamp  produces  all  the  light  there  is.  .  .  . 
It  is  the  standard  equipment  of  the  nation's  largest  and 
finest  theatres.  .  .  .  Used  by  90%  of  the  largest  Drive-In 
Theatres.  .  .  . 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  light  volume,  when 
used  with  projectors  that  have  efficient  DISC  type 
revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions. 


I  I 


WHY    EXPERIMENT? 


i  i 


J.E.McAULEY  MFG. CD. 

552-554    WEST   ADAMS    STREET 
CHICAGO   6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST 


March  1949 


INTERNATIONAL 

PR0JECYI0NIS1 


With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


MARCH  ,1949 


Number  3 


Index  and  Monthly  Chat 5 

This     'Matching'     of     Projection 

Optics    7 

Robert  A.  Mitchell 

The  Present  Status  of  Theatre  Tv  10 
A  Report  by  the  SMPE 

Emergency   Operation    of   Sound 

Systems   14 

Edward  Stanko 

Letters  to  the  Editor 16 

IA  Elections   16 

T-Number     vs.     F-Number    Lens 
Markings 17 

New  Altec  Mini-Mike 17 


In  The  Spotlight    18 

Harry  Sherman 

Total    Lumens    vs.    Screen    Light 

Distribution    20 

Mark  Stevens 

National     Carbon     Co.     Releases 
Data  on  9-mm  H-I  Carbon.  ...    21 

An  Exhibitor  Assays  Tv  as  Movie 
Theatre  Competition    22 

Simplex  In-A-Car  Speaker    22 

Relative  Toxicity  of  Nitrate  and 

Acetate  Film  Stock    24 

Dr.  E.  K.  Carver 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING   CO.,   INC. 

19  West  44  Street,  New  York   18,  N.   Y. 

R.   A.   ENTRACHT,   Publisher 

SUBSCRIPTION   REPRESENTATIVES 

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wond-class  matter  February  8,  1932,  at  the  Post  Office  at  New  York,  N.  Y.,  under  the 
act  of  March  3,  1879.  Entire  contents  copyrighted  '1949  by  International  Projectionist 
Publishing  Co.,  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


MONTHLY   CHAT 

THE  very  able  R.  H.  Cricks,  technical 
editor  of  the  British  journal  Ideal 
Kinema,  observes  that  British  projectors 
have  been  "paid  the  highest  possible 
compliment"  by  the  publication  recently 
in  IP  of  descriptions  of  the  British-made 
Kalee  GK  21  and  B.T.H.  Supa  mecha- 
nisms. Mr.  Cricks  also  notes  the  IP  state- 
ment that  "American  motion  picture 
equipment  no  longer  dominates  the  world 
market".    Mr.  Cricks  continues: 

"I  am  the  last  to  decry  American  pro- 
jectors: of  the  Simplex,  the  only  Ameri- 
can machine  widely  used  in  this  country, 
I  can  conscientiously  say  that  it  is  the 
only  machine  of  which  I  have  never  heard 
of  mechanical  trouble.  Nevertheless,  my 
view  as  an  engineer  is  that  British  pro- 
jection equipment  is  years  ahead  of 
American  design." 

British  superiority,  opines  Mr.  Cricks, 
is  due  to  the  fact  that  "for  the  first  time 
we  have  an  outfit  designed  from  the 
ground  up  as  an  integral  unit,  capable  of 
doing  everything  that  is  demanded  of  a 
modern  sound  projector".  Now,  Mr. 
Cricks  will  concede  that  at  least  four 
American  projectors — Brenkert,  Century, 
Motiograph,  and  Simplex — accomplish 
precisely  the  same  thing,  not  only  in 
America  but  in  far-flung  corners  of  the 
world  which  never  see  a  serviceman. 
Tasting  is  in  the  eating. 

Anent  the  "modernity"  of  these  new 
British  projector  designs,  we  submit  the 
following  comment  by  a  British  techni- 
cian of  vast  experience  in  projection  mat- 
ters in  and  outside  Great  Britain: 

"I  fully  agree  with  remarks  in  'Monthly 
Chat'  in  IP  for  December  last.  I  should 
dearly  like  to  write  an  article  debunk- 
ing these  British  projectors  of  recent  de- 
sign, but  obviously  I  cannot.  I'm  all  for 
standardization  of  equipment,  thus  I 
think  that  stuff  like  the  SUPA  is  com- 
pletely  retrograde. 

"Any  exhibitor  who  is  kidded  into  buy- 
ing one  of  these  outfits  is  completely  tied 
to  one  firm  for  many  years  to  come.  From 
the  projectionist's  viewpoint,  such  appa- 
rati  mean  that  he  has  either  got  to  be  a 
superserviceman  to  maintain  it,  or  he 
must  be  a  brainless  coot. 

"The  Kalee  21  isn't  quite  so  unortho- 
dox a  design,  but  here  again  the  buyer  is 
tied  down  to  one  supplier  for  any  future 
development.  I  can  understand  and  ap- 
preciate the  utility  of  a  streamlined  air- 
craft, automobile  or  railroad  locomotive, 
but  I'm  darned  if  I  can  see  the  sense  of  a 
streamlined  projector.  And  streamlining 
is  about  the  only  'modern'  aspect  of  these 
mechanisms." 

IP  is  pretty  much  in  agreement  with 
this  observation;  and  the  need  for  con- 
stant servicing  of  British  projectors  has 
been  stressed  by  our  Canadian  friends 
who  operate  these  mechanisms. 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


INTERNATIONAL    PROJECTIONIST 


VOLUME  XXIV 


MARCH  1949 


NUMBER  3 


This  Matching'  of  Projection  Optics 


THE  vexing  matter  of  matching  pro- 
jector optical  elements  has  evoked 
sharper  differences  of  "expert"  opin- 
ion than  any  other  topic  in  modern  pro- 
jection technology.  Everyone  agrees  that 
screen  results  are  best  when  the  projec- 
tion lens  is  optically  matched  to  the  lamp 
condensing  system,  but  beyond  this 
simple  concession  all  is  confusion  and 
misconceptions  abound. 

This  bewildering  state  of  affairs  ap- 
pears to  be  due  in  part  to  uncertain  and 
'conflicting  ideas  of  what  constitutes  a 
state  of  perfect  optical  balance  in  a  mo- 
tion picture  projector.  Failure  to  agree 
on  a  definition  of  the  term  "matched 
optics"  has  been  lamented  by  optical 
technicians.1 

The  fact  that  acknowledged  authori- 
ties disagree  on  so  fundamental  a  matter 
imposes  an  undeserved  handicap  upon 
the  projectionist  who  daily  assumes  re- 
sponsibility for  the  performance  of  pro- 
jector optical  trains.  Little  benefit  will 
result  from  academic  discussions  of 
matched  optics  until  the  individual  pro- 

1  See  "Uniform  Screen  Illumination  as  Related  to 
High-Speed  Len9es,"  by  Dr.  John  L.  Maulbetsch;  IP 
for  Sept.,  1947,  p.  5;  also  the  symposium  "Matched 
High-Speed  Projection   Optics,"  IP,  April,  1948,  p.  13. 


By  ROBERT  A.  MITCHELL 

jectionist  knows  beyond  all  doubt  how 
the  equipment  in  his  own  projection  room 
measures  up  against  the  criterion  of 
optimum  matching  conditions. 

Definition  of  Terms 

What  exactly  is  meant  by  a  condition 
of  perfectly  matched  projector  optics? 
We  can  settle  this  matter  definitely  only 
by  considering  what  happens  to  the  light 
as  it  passes  through  the  projector  optical 
train. 

It  is  commonly  supposed  that  the 
optical  speed  of  the  lens  should  be  the 
same  as  the  rated  speed  of  the  lamp 
mirror  or  condenser  to  insure  a  condi- 
tion of  "match"  between  these  two  ele- 
ments. If  we  consider  the  aperture  as  a 
mere  point — a  very  small  pinhole,  let  us 
say — this  theory  appears  to  be  true,  as 
demonstrated  by  Fig.  1.  Lines  drawn 
from  the  edges  of  the  mirror  are  inter- 
cepted at  the  edges  of  the  lens  and  no 
light  is  presumably  wasted.    In  this  dia- 


Pinhole  aperture 


gram  the  projection  lens  is  represented 
by  a  single  element  for  the  sake  of 
clarity. 

This  theory  is  very  attractive  because 
it  is  so  very  simple.  How  shocked  we 
shall  be  if  more  careful  consideration 
shows  it  to  be  false! 

What  about  that  "pinhole  aperture"? 
A  projector  aperture  is  not  a  mathemati- 
cal point,  so  why  should  it  be  considered 
as  one?  An  aperture  is  an  area  which 
compares  favorably  with  the  area  of  the 
lens  opening.  The  light  rays  from  the 
lamp  must  cover  the  entire  aperture, 
hence  they  impinge  upon  the  lens  sur- 
face from  many  different  directions.  Yes, 
we  are  forced  to  conclude  that  the  simple 
theory  fails  to  represent  the  conditions 
existing  in  a  projector  optical  train. 
Fig.  1  is  not  only  inapplicable  to  the 
problem  of  projection  optics,  but  is  actu- 
ally misleading! 

Let  us  replace  Fig.  1  by  another  dia- 
gram (Fig.  2)  in  which  two  "point 
apertures"  are  used,  the  distance  be- 
tween the  points  being  the  same  as  the 
diagonal  of  a  35-mm  projector  aperture 


Two  pinhole 

apertures 
1  inch  apart 


£:2.5 


P:2.5 


FIG.  1.  An  F:2.5  lens  "matched"  to  an  F:2.5  mirror — in  theory,  but  not 
as  conditions  exist  in  an  actual  projector. 


FIG.  2.    Showing  actual  optical  conditions  in  a  projector.    Note  that 

an  F:2.5  lens  does  not  match  an  F:2.5  mirror.    A  large  proportion  of 

the    light   from    the    illuminated    aperture    is    lost. 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


-approximately  1  inch.  Here  again  an 
artificial  device  is  employed,  for  no  pro- 
jector aperture  consists  of  two  pinholes. 
But  this  course  is  justified  because  the 
points  define  the  maximum  limits  of  a 
real  aperture  and  accordingly  define  the 
dimensions  and  "spread"  of  the  light 
beam  emerging  from  a  real  aperture. 

Now  examine  Fig.  2.  It  employs  the 
same  mirror-lens  combination  used  in 
Fig.  ,1.  Would  you  say  that  the  lens 
matches  the  mirror  in  this  case?  Of 
course  not.  The  F:2.5  lens  fails  con- 
spicuously to  intercept  all  of  the  light 
emerging  from  the  two  pinhole  apertures 
in  Fig.  2.  A  more  rapid  (larger)  lens 
must  be  used  if  we  are  to  obtain  an 
optical  match. 

If  now  we  replace  the  two-pinhole 
scheme  by  an  actual  aperture2  and  view 
the  light  beam  perpendicularly  to  the 
diagonal  of  the  aperture,  we  shall  ob- 
tain visible  proof  that  Fig.  2  represents 
perfectly  the  outermost  boundaries  of 
the  flood  of  intense  light  pouring  from 
the  aperture. 

Basis  for  the  Definition 

Now  for  that  much-needed  definition. 
Fig.  2  will  help  us  see  what  is  really 
meant  by  "matched  optics".  If  the  lens 
in  Fig.  2  were  larger — say,  just  large 
enough  to  touch  the  outermost  light  rays 
—no  light  would  be  wasted,  all  of  it 
being  brought  to  a  focus  on  the  screen. 
Is  it  not  obvious  that  if  the  lens  is  just 
large  enough  to  catch  all  of  the  light 
coming  from  the  aperture — not  a  bit  too 
large  or  too  small — we  could  in  all  truth 
say  that  the  lens  exactly  matches  the 
lamp  optics?  If  we  agree  to  this,  our 
definition   practically  writes  itself. 

A  state  of  optical  match  between  pro- 
jector lens  and  lamp  optics  exists  when 
the  lens  has  sufficient  "speed"  to  inter- 
cept and  utilize  all  of  the  light  emerg- 
ing from  the  aperture. 

This  optical  condition  is  the  most  effi- 
cient possible,  and  hence  may  be  ex- 
pected to  provide  maximum  picture 
brightness  and  uniformity  of  illumina- 
tion. 

.  The  implications  of  this  definition  re- 
quire us  to  investigate  certain  features 
of  projection  optics.  We  have  yet  to 
work  out  a  method  of  finding  the  lens 
speeds  which  match  given  lamp  con- 
densing systems. 

The  optical  speeds  of  lenses  are  indi- 
cated by  F-numbers.  An  F-number  is 
simply  focal  length  divided  by  clear 
diameter.  If  a  projection  lens  has  an 
equivalent  focus  of  4V2  inches  and  a 
clear  opening  of  2.37  inches,  its  speed 
rating    is    F:    4.5/2.37,   or    F:1.9    (very 

.  2-The  dimensions  of  the  35-mm  soundnlm  aperture 
are  0.825  by  0.600  inch.  The  diagonal  of  a  square- 
cornered  aperture  is  l".04O6:  of  a  round. cornered 
aperture,  1".0107.  when  the  corners  are  curves  of 
radius    0".047. 


nearly).  The  lower  the  F-number,  the 
more  rapid  and  efficient  the  lens :  an 
F:2.0  lens  is  "faster"  than  an  F:2.5  lens 
By  all  appearances,  the  speeds  of  lamp 
mirrors  and  condensers  arc  expressed  by 
the  same  system  of  F-numbers.  Such, 
however,  is  not  the  case,  though  many 
projectionists  seem  to  be  unaware  of  this 
fact.  This  is  not  surprising,  however, 
for  lamp  manufacturers  have  ever  flaunt- 
ed the  spurious  F-number  ratings  of  their 
condensing  systems  as  indications  of 
optical  speed. 

Genesis  of  F-Number 

The  F-numbers  commonly  assigned  to 
lamp  mirrors  are  obtained  by  dividing 
the  working  distance  by  the  diameter  of 
the  mirror.  (Working  distance  is  the 
distance  from  thj  center  of  the  mirror 
to  the  center  of  the  aperture.)  Thus,  a 
10-inch  mirror  placed  25  inches  from 
the  aperture  is  rated  F:  25/10,  or  F:2.5. 
Lamp  manufacturers  usually  choose  a 
working  distance  at  which  the  image  ol 
the  positive  crater  on  the  aperture  is  just 
about  large  enough  to  fill  the  entire  rec- 
tangular opening  with  even  illumination. 

It  may  be  argued  that  better  screen 
results  could  be  obtained  by  shortening 
the  working  distance  a  trifle  below 
manufacturers'  recommendations,  but  to 
do  so  would  arouse  a  storm  of  protest 
from  makers  of  mirrors  and  lamps.  The 
writer  emphasizes  the  arbitrariness  of 
assigned  working  distances;  he  makes 
no  argument  whatever  concerning  them. 

The  true  F-numbers  of  lamp  condens- 
ing elements  must  be  distinguished  from 
the  spurious  ones.  The  true  F-number 
ratings  show  that  modern  projection 
lamps  are  very  much  "faster"  than  is 
commonly  supposed.  They  may  be  found 
by  the  same  rule  which  determines  pro- 
jection lens  F-numbeis,  namely,  focus 
divided  by  diameter. 

The  true  focal  length  of  a  mirror  or 
condenser,  however,  is  neither  the  work- 
ing distance  nor  the  "geometric  focus" 
(distance  from  the  crater  of  the  positive 
carbon  to  the  center  of  the  condensing 
element).  The  following  formula  give? 
a  very  good  indication  of  true  focus  when 

Mirror  rated. 1: 2.5 


geometric    focus    and    working    distance 
are  known: 


Optics   -matched 
Condenser  rated  J?:2.5 


F.1.5 


Optics  not  matched 
in  -this  case 

FIG.    3.     A   projection    lens   which    is   matched 

to    one    lamp    is    not    necessarily    matched    to 

another    lamp    having    the    same   "speed". 


True  focal  length  = 
Geom.  focus  X  Working  dist. 

Geom.  focus  -|-  Working  dist. 


Here  is  why  the  spurious  F-numbers 
of  lamp  condensing  elements  are  at  best 
only  imperfect  indications  of  optical  effi- 
ciency. Manufacturer  Jones  builds  a 
lamp  using  a  10-inch  mirror  which  pro- 
vides optimum  results  (a  satisfactory 
image  of  the  positive  crater  on  the  aper- 
ture) when  a  working  distance  of  25 
inches  is  employed.  The  crater  image  is 
formed  when  the  positive  carbon  crater 
is  6  inches  from  the  center  of  the  mirror, 
the  geometric  focus. 

The  spurious  rating  of  this  mirror,  the 
F-number  Jones  will  assign  to  it,  is 
F:  25/10,  or  F:2.5.  The  actual  optical 
speed  of  the  mirror  is: 

6X  25 

(1)  True  focus  = =  4.84  in. 

'  6  +  25 

4.84 

(2)  True  speed  =  =  F:0.484 

10 

Manufacturer  Smith,  on  the  other 
hand,  designs  a  lamp  also  utilizing  a 
10-inch  mirror  working  at  a  distance  of 
25  inches.  The  geometric  focus  of 
Smith's  mirror,  however,  is  4  inches. 
The  spurious  rating  of  Smith's  mirror  is 
F:25/10,  or  F:2.5,  the  same  as  Jones' 
mirror.  But  the  true  speed  of  Smith's 
mirror  is: 


'1)  True  focus  = 


4X25 

4+25 
3.45 


(2)   True  speed  = 


3.45 


F:0.345 


10 


'True'  Speed  Ratings  for  Mirrors 

Although  both  these  mirrors  are 
erroneously  rated  as  F:2.5,  the  true  speed 
of  Jones'  mirror  is  F:0.484,  and  the  true 
speed  of  Smith's  mirror  is  F:0.345. 
Smith's  mirror,  having  the  lower  F-num- 
ber, is  accordingly  "faster"  than  Jones' 
mirror.  In  fact,  the  optical  efficiency  of 
Smith's  lamp  is  fully  140%  that  of  Jones' 
lamp"  (1/.345  divided  by  1/.484  times 
100  equals   140%). 

We  cannot  escape  the  conclusion  that 
the  spurious  F-numbers  used  by  lamp 
manufacturers  to  rate  mirror  and  con- 
denser speeds  are  of  no  value  whatever 
in  any  consideration  of  matched  optics! 

But  this  is  not  all.  It  can  also  be 
proved    that    a    lens    which    is    perfectly 

;:  It  may  be  inferred  from  this  comparison  that  the 
efliciency  of  lamp  mirrors  may  be  increased  by  having 
the  focal  length  as  short  as  possible.  That  is  true; 
but  the  shortness  of  focus  is  limited  by  the  diameter 
of  the  positive  crater.  To  exceed  this  limit  would 
result  in  an  oversize  spot  at  the.  aperture,  with  con- 
sequent waste   of  light. 


INTERNATIONAL  PROJECTIONIST-    •     March  1949 


matched  to  the  optics  of  one  lamp  is  not 
necessarily  matched  to  other  lamps  hav- 
ing the  same  speed,  true  or  spurious. 

Figure  3  shows  two  lamp  optical  sys- 
tems, one  having  a  10-inch  mirror  placed 
25  inches  from  the  aperture  (A)  and 
the  other  a  4-inch  condensing  lens  placed 
10  inches  from  the  aperture  (B).  (The 
condenser  is  shown  as  a  single  biconvex 
lens  to  simplify  the  drawing.  Actual 
condensing  lens  assemblies,  consist  of 
two  plano-convex  or  aspheric  lenses. 
This  diagram  does  not  represent  any 
actual  equipment.) 

Both  lamps,  it  may  be  seen,  have  the 
false  speed  of  F:2.5,  and  if  the  crater 
to  converger  distances  were  proportional, 
they  would  have  the  same  true  speed,  or 
F-number. 

Unorthodox  Conclusions  Reached 

Observe  that  the  beam  from  the  aper- 
ture "spreads"  most  rapidly  when  the ' 
comparatively  close  condenser  is  em- 
ployed. The  result  is  that  the  F:1.5  lens 
which  matches  the  F:2.5  mirror  is  too 
"slow"  to  match  the  F:2.5  condenser! 
Another  unorthodox  conclusion  is  forced 
upon  us:  that  even  the  true  optical  speeds 
of  lamp  condensing  systems  should  not 
enter  directly  into  a  consideration  of 
optical  matching  in  projectors!  And 
more  surprising  facts  are  in  store  for  us. 

At  this  point  we  may  advantageously 
review  our  definition  of  matched  optics. 
You  will  recall  that  lamp-optic  speeds, 
real  or  otherwise,  were  not  even  men- 
tioned in  the  definition.  Nor  is  there 
any  need  to  bother  with  them.  For  the 
remainder  of  this  discussion,  where  we 
really  get  down  to  brass  tacks,  lamp 
speeds  will  be  entirely  ignored. 

Our  definition  makes  it  clear  that  we 
need  be  directly  concerned  only  with  the 
dimensions  of  the  aperture  light  beam 
at  a  distance  from  the  aperture  equal  to 
the  focal  length  ('"infinity  focus  posi- 
tion") of  the  lens  being  used  Ordinary 
observation   reveals   that   the   light   from 


TABLE 

A 

Projection 

Matched 

Lens  E.F. 

Speed 

4  inches 

F:1.51 

'..-..     5    .  " 

F:1.63 

6    ■« 

F:1.72 

7       « 

F:1.80 

8 

F:1.86 

le  aperture  diverges,  or  spreads  out. 
The  degree  of  divergence,  and  hence  the 
diameter  of  the  light  beam  at  the  speci- 
fied distance  from  the  aperture,  depends 
on  the  dimensions  of  the  aperture,  the 
diameter  of  the  mirror  or  condenser,  and 
the  working  distance  of  the  mirror  or 
condenser. 

These    interrelated    functions    may    be 
integrated  to   give   an   expression  which, 


[  lens   matching  1 

Vlamp  optics     J p  i                        m 

^*                                       1  + 

6 

^tf+wl   -2y 

>+ ^_ 

1+  5_ 

y'X+w*  -  2§ 

-2  — 

FIG.  4.  This  formula  is  the  basis  for  the  optical 
matching  principles  discussed  in  the  accom- 
panying article.  The  simplified  35-mm  matched 
optics  formula  was  derived  from  this  general 
formula,  in  which  t  is  the  E.  F.  of  the  pro- 
jection lens,  m  is  the  working  distance  of  the 
condenser  element,  h  is  aperture  height,  w  is 
aperture  width,  and  r  is  the  radius  of  the 
aperture  corners  if  they  be  rounded.  All  dimen- 
sions are  in   inches. 

when  used  as  a  divisor  of  focal  length, 
gives  the  F-number  of  a  perfectly 
matched  lens  of  that  particular  E.F. 

A  Simplified  General  Formula 

Figure  4  presents  the  completely  re- 
solved general  formula  for  the  computa- 
tion of  lens  matching  speeds.  However, 
there  is  no  need  for  theatre  projection- 
ists to  employ  this  complicated  expres- 
sion. The  fortunate  fact  that  the  diagonal 
of  the  35-mm  soundfilm  aperture  is  very 
close  to  1  inch  makes  possible  an  amaz- 
ing simplification  of  the  general  formula. 
It  should  be  remembered,  though,  that 
the  simplified  formula  is  applicable 
only  to  35-mm.  soundfilm  projectors. 
"Matched"  lens  F-number  = 

Working  dist. 

Lens  E.F.  X  

Mirror  diam.  +  1 


Working  dist. 


Lens  E.F. 


Mirror  diam.  +  1 

This  simplified  matching  formula  is  very . 
easy  to  use.  Following  is  a  complete 
explanation  of  the  four  steps  required. 
To  find  the  F-n umber  of  a  lens  of  given 
E.F.  which  exactly  matches  any  specified 
lamp  optical  system:  (Note:  When  con- 
densing lenses  arc  used,  the  word  "mir- 
ror" should  be  changed  to  "condenser." 

1.  Divide  the  mirror-aperture  dis- 
tance by  the  diameter  of  the  mirror 
plus  1  inch. 

2.  Multiply  the  number  found  in 
(1)  by  the  E.F.  of  the  projection  lens 
in  inches.  (Retain  this  result  for  use 
in   (4).) 

3.  Add  to  the  number  found  in  (1) 
the  E.F.  of  the  projection  lens  in  inches. 

4.  Divide  the  number  found  in  (2) 
by  the  number  found  in    (3). 

The  results  obtained  by  using  this 
formula  are  rather  startling.  In  the 
great  majority  of  cases  the  speeds  of 
projection    lenses   matching   lamp   optics 


are   considerably   higher   than   the   most 
rapid  lenses  available  commercially! 

Two  Typical  Examples  Cited 

A  certain  well  known  arc  lamp,  for 
example,  has  a  mirr"or  11%  inches  in 
diameter  and  a  working  distance  of  ap- 
proximately .30  inches.  In  Table  A  are 
tabulated  the  F-numbers  of  lenses  of 
different  focal  lengths  which  exactly 
match  the  optics  of  this  lamp. 

Another  widely  used  arc  lamp  employs 
a  condensing  lens,  the  converging  ele- 
ment of  which  is  6  inches  in  diameter. 
The  working  distance  is  12  inches.  The 
F-numbers  of  a  few  lenses  which  match 
this  lamp   are  shown  in  Table  B. 

The  failure  of  the  most  rapid  com- 
mercial lenses  to  fulfill  the  requirements 
of  exact  matching  in  most  cases  may 
not  be  quite  as  serious  a  matter  as  it 
would  seem  at  first  thought.  The  Hght 
beam  coming  from  the  aperture  is  not 
homogeneous.  Its  outer  regions  are  far 
less  intense  than  the  central  parts,  thus 
the  loss  in  picture  brightness  and  uni- 
formity of  illumination  will  not  be  seri- 
ous if  the  size  of  the  lens  comes  up  to  a 
certain  optimum  speed  which  may  be 
considered  a  satisfactory  approach  to  the 
ideal  state  of  perfect  matching. 

But  common  sense  cautions  us  to  bear 
in  mind  that  the  cross-sectional  area  of 
the  outer,  fainter  portions  of  the  light 
beam  is  too  great  to  be  entirely  ignored. 
A  happy  medium  must  be  ascertained  in 
this  as  in  other  matters  of  choice  be- 
tween the  impracticable  ideal  and  the 
commercially  feasible. 

The  writer  has  no  idea  what  percent- 
age of  the  perfectly  matched  speed  the 
optimum  speed  should  be.  This  matter 
requires  extensive  experimentation  and 
a  high  order  of  judgment.  If  we  arbitra- 
rily set  the  optimum  lens  speed  at  80% 
of  the  matched  lens  speed,  then  a  lamp 
system  which  requires  an  F:1.5,  4-inch 
lens  for  perfect  matching  would  function 


TABLE 

B 

Projection 

Matched 

Lens  E.F. 

Speed 

4  inches 

F:1.13 

5      " 

F:1.19 

6      " 

F:1.24 

7       " 

F:1.28 

8      " 

F:1.31 

acceptably  with  an  F:1.9,  4-inch  lens 
(80^  X  .1/1.5  =  1/1-9).  The  writer 
opines,  however,  that  80  percent  is  not 
sufficient. 

.  How  can  the  question  of  optimum  lens 
speed  be  settled?  The  Society  of  Motion 
Picture  Engineers  appears  to  be  the  logi- 
cal body  to  conduct  such  an  investigation. 
After  observations  on  all  types  of  pro- 
[Continued  on  page  33) 


INTERNATIONAL   PROJECTIONIST     •      March   1949 


The  Present  Status  of  Theatre  Tv 


DURING  1944-46  the  Theatre  Tele- 
vision Committee  of  the  SMPE 
worked  on  many  of  the  various  en- 
gineering problems  related  to  placing 
television  in  the  motion  picture  theatre. 
Also  during  these  years,  Paul  J.  Larsen, 
together  with  other  representatives  of  the 
Society,  appeared  before  the  Federal 
Communications  Commission  (FCC)  and 
succeeded  in  obtaining  for  the  motion 
picture  industry  frequency  allocations  for 
theatre-Tv  use  on  an  experimental  basis 
only. 

The  Motion  Picture  Association  (MPA) 
was  then  approached  with  repeated  re- 
quests that  it  cooperate  in  the  work  of 
the  SMPE,  if  it  had  any  reason  to  believe 
that  it  would, be  practical.  Neither  pro- 
ducers nor  distributors,  however,  were 
interested  in  theatre-Tv  at  that  time,  nor 
were  they  particularly  concerned  about  Tv 
as  a  competitive  entertainment  medium. 
The  exhibitors,  on  the  other  hand, 
showed  some  concern  but  did  not  wish  to 
take  any  active  measures  either  on  their 
own  or  with  the  SMPE.  The  general 
attitude  seemed  to  be  that  it  might  be 
possible  to  buy  into  the  Tv  industry  at 
some  future  date  and  thereby  save  the 
high  cost  of  research  and  development. 
Freeze-out  Is  Narrowly  Averted 

In  November  1946  a  point  had  been 
reached  where  it  was  believed  that  a  defi- 
nite statement  of  interest  by  the  motion 
picture  industry  was  required  if  the  work 
were  to  continue.  In  addition,  public 
hearings  before  the  FCC  were  scheduled 
for  early  1947  at  which  it  was  proposed 
to  reallocate  to  other  services  the  fre- 
quencies provided  for  experimental  thea- 
tre use. 

In  spite  of  the  lack  of  interest  shown, 
the  SMPE  again  undertook  having  a  brief 
prepared,  and  Mr.  Larsen  appeared  be- 
fore the  FCC  on  February  4,  1947  (FCC 
Docket  No.  6651).  Immediately  preced- 
ing the  hearings  a  telegram  was  received 
from  the  MPA  endorsing  the  SMPE's 
stand.  A  similar  telegram  was  sent  to  the 
FCC  three  weeks  following  the  hearings 
by  the  independent  producers. 

The  decision  of  the  FCC  was  handed 
down  early  in  1948,  and  while  it  did  not 
provide  specific  frequency  allocations  for 
theatre  use,  it  did  make  available  certain 
frequencies  which  still  could  be  used  by 
the  motion  picture  industry  for  experi- 
mental purposes. 

Consequently,  even  though  the  indus- 
try's position  is  weaker  from  the  stand- 
point of  obtaining  a  permanent  part  of 
the  spectrum;  the  SMPE  decided  to  con- 


10 


This  interim  report  of  the  Theatre  Tv  Committee  of  the  Society  of  Motion 
Picture  Engineers,  presented  here  in  condensed  form,  is  a  statement  of 
the  present  state  of  the  art  written  in  non-technical  language.  In  addi- 
tion to  its  wealth  of  useful  information,  this  candid  appraisal  of  the  cur- 
rent situation  constitutes,  in  the  opinion  of  IP,  an  indictment  of  the 
motion  picture  industry  on  the  score  of  its  shortsightedness,  ineptness, 
lack  of  courage  and  downright  stupidity  for  its  failure  to  assume  its  proper 
place  in  the  development  of  this  new  entertainment  medium. 


tinue  its  engineering  work.  It  was  agreed 
to  prepare  a  comprehensive  report  outlin- 
ing the  present  state  of  the  art  in  so  far 
as  it  regards  the  motion  picture  theatre, 
and  again  to  seek  the  cooperation  of  the 
industry  as  a  whole. 

Governmental  Regulations  Outlined 

No  Federal  license  or  governmental 
permission  is  required  for  the  establish- 
ment of  a  theatre-Tv  receiving  station, 
either  for  the  reception  of  programs  by 
wire  or  coaxial  cable  or  by  radio.  How- 
ever, municipal  regulations  may  control 
the  placement  of  masts  or  other  structures 
on  roofs,  the  guying  of  reinforcements  of 
such  structures,  and  the  safety  of  any 
electrical  wiring  of  permanent  nature 
installed  in  the  theatre. 

If  high  towers  are  erected  for  recep- 
tion, and  if  these  are  so  located  that  they 
may  become  an  obstacle  or  hazard  to 
aerial  navigation,  it  is  possible  that  the 
Civil  Aeronautics  Authority  must  grant 
approval  prior  to  the  erection  of  such 
facilities. 

If  one  or  more  theatres  in  a  given  city 
are  to  receive  a  Tv  program  from  central 
studios,  means  must  be  provided  for 
carrying  the  program  from  the  central 
studios  to  the  theatres  in  question.  The 
program  may  originate  from  live-talent 
presentations  in  the  studio  (or  at  remote 
pickup  points  such  as  sports  arenas, 
legitimate  theatres,  or  the  like),  or  they 
may  originate  from  film  records  previ- 
ously made. 

They  may  be  carried  to  the  theatres  by 
means  of  specially  equalized  telephone 
lines  or  by  coaxial  cables,  either  of  which 
presumably  will  be  furnished  by  the  local 
telephone  company  or  other  public-utility 
common  carrier  in  the  communications 
service.  Alternatively,  the  programs  may 
be  sent  by  narrow  radio  beams  from  a 
central  transmitting  station  to  the  indi- 
vidual theatres,  where  they  are  received 
on  highly  directional  antennas  or  aerials. 
If  radio  beams  are  to  be  used,  it  be- 
comes necessary  to  secure  the  approval 
of  the  FCC  and  to  receive  a  construction 


permit  and,  thereafter,  a  station  license 
to  permit  the  operation  of  the  transmitter 
which  sends  the  studio  program  to  the 
various  theatres. 

Non-Broadcast  Type  Transmission 

The  transmissions  in  question  are  not 
broadcast  (that  is,  addressed  to  the  gen- 
eral public),  and  a  broadcasting  license 
would  not  be  required  from  the  FCC. 
The  transmissions  are  rather  of  the  type 
known  as  multiple-addressee  messages, 
which  are  private  communications  ad- 
dressed by  a  single  sender  to  a  group  of 
recipients,  each  of  whom  receives  the 
same  message.  Such  messages,  unlike 
broadcasts,  are  private  in  nature  and  are 
not  legally  available  to  the  public. 

Any  central  transmitter  erected  to  send 
Tv  programs  to  a  group  of  theatres  will 
require  a  suitable  tower  to  support  the 
transmitting  equipment.  If  this  tower  is 
a  potential  aeronautical  hazard,  authori- 
zation will  be  required  from  the  CAA  for 
its  erection.  Municipal  codes  relative  to 
the  establishment  of  towers  in  residential 
districts  must  also  be  considered. 

The  FCC  has  taken  the  present  stand 
that  the  distribution  of  material  of  a  pri- 
vate nature,  such  as  is  here  contemplated, 
falls  within  the  scope  of  the  common 
carriers  and  that  it  should,  therefore,  be 
handled  by  a  telephone  or  telegraph  com- 
pany. It  is  not  known  whether  the  FCC 
will  permanently  adhere  to  this  policy, 
particularly  in  the  case  of  urban  Tv 
studios  and  transmitters  for  syndication 
of  programs  to  theatres. 

Commercial  Theatre-Tv  Requisites 

In  any  case,  the  channels  (frequen- 
cies) assigned  to  such  Tv  transmissions 
necessarily  would  be  different  from  those 
used  for  Tv  broadcasting.  The  channels 
would  probably  be  at  considerably  higher 
frequencies,  would  be  wider  (to  accom- 
modate possibly  higher-detail  pictures,  or 
color  pictures,  or  both)  and  might  differ 
from  the  broadcasting  channels  in  other 
respects  as  well. 

The  SMPE  has   previously  requested 


INTERNATIONAL  PROJECTIONIST    •    March  1949 


bffl/'$uper-{/g/)/nffflity$rkns2n(/see! 


THESE  jumbo  screens  used  in  big,  drive-in 
theatres  require  projection  light  of  terrific 
brilliance.  Otherwise,  your  patrons  can't  get 
that  bright-screen  sparkle  they  are  used  to  in 
first-run,  conventional  theatres.  They  have  to 
squint  to  see. 

Give  your  patrons  vivid,  easy-to-see  pictures 
by  using  "National"  Super-High  Intensity 
carbons  in  your  drive-in  theatre.  These  carbons 
give  you  brighter  light  than  any  other  source 
of  projection  light  obtainable.  And,  because 
"National"  Super-High  Intensity  carbons  pro- 
duce light  of  almost  perfect  color  balance, 


your  color  movies  glow  with  rich  detail. 

The  slight  extra  cost  of  "National"  Super- 
High  Intensity  carbons  is  negligible  when  you 
consider  the  advantages  in  audience  approval 
and  bigger  box  office.  Write  for  complete 
details. 

The  term  "National"  is  a  registered  trade-mark  of 

NATIONAL   CARBON    COMPANY,    INC. 

Unit  of  Union  Carbide  and  Carbon  Corporation 

EBB 

30  East  42nd  Street,  New  York  17,  N.  Y. 

Division  Sales  Offices:  Atlanta,  Chicago,  Dallas,  Kansas  City. 

New  York,  Pittsburgh,  San  Francisco 


Use  "National"  Super -High  Intensity  carbons  for  "the  brightest  spot  in  the  world/ 


INTERNATIONAL  PROJECTIONIST 


March  1949 


11 


allocations  of  channels  from  the  FCC  for 
commercial  theatre-Tv  but  that  request 
has  not  as  yet  been  granted.  It  is  not 
known  whether  the  FCC  ultimately  would 
grant  such  channels,  but  it  is  believed 
that  their  grant  would  require  the  fol- 
lowing steps: 

An  individual  theatre  owner  planning 
to  establish  a  Tv  service  to  its  theatres 
would  first  apply  for  an  experimental 
license  from  the  FCC  to  permit  him  to 
transmit  his  programs,  purely  experi- 
mentally and  non-commercially,  for  a  spe- 
cific period.  He  would  be  obligated  to 
describe'  his  plans  clearly,  and  to  report 
from  time  to  time  to  the  FCC  on  his  tech- 
nical progress. 

If  his  experiments  were  successful,  he 
might  then  ask  that  his  experimental 
license  be  converted  into  a  commercial 
license  permitting  normal  and  continued 
operation  during  the  period  of  the  license 
(which  might  be  set  at  three  years,  or 
some  similar  period).  The  FCC  then 
doubtless  would  hold  hearings  to  deter- 
mine the  need  for  and  desirability  of  the 
service  in  question.  If  it  found  that  the 
service  was  useful  and  necessary  and  that 
channels  were  available,  it  would  then 
grant  the  corresponding  commercial  li- 
cense. City-allocation  hearings  would  also 
be  held. 

It  should  be  added  that  each  theatre 
chain  in  the  same  city  would  require  its 
own  transmitting  facilities  or  wire  net- 
work (unless  an  interchange  of  programs 
or  the  common  use  of  a  single  transmitter 
were  acceptable  to  all  involved) .  That  is, 
for  completely  independent  service  each 
theatre  group  would  require  its  own 
transmitter,  its  own  receivers,  and  its  own 
channel  allocations  from  the  FCC. 

An  individual  theatre  owner  or  theatre 
circuit  might  arrange  for  transmission 
of  its  programs  by  an  existing  Tv  station 
or  licensee  in  a  manner  similar  to  current 
■commercial  Tv  broadcasts. 

In  addition,  for  remote  pickups  outside 
the  main  studios  it  becomes  necessary  (if 
radio  is  to  be  used  to  carry  the  program 
from    the    remote    point    to    the    central 


studios  for  retransmission  to  the  theatres) 
to  secure  an  FCC  license  for  the  radio- 
beam  transmitter  which  will  carry  such 
programs.  Channels  are  presently  avail- 
able for  that  purpose  and  might,  for  good 
reason,  be  obtained. 

Syndication  by  Radio  Relay 

When  nation-wide  syndication  is  in- 
volved, it  becomes  necessary  to  intercon- 
nect the  central  studios  of  each  network 
in  the  cities  in  which  it  serves  theatres  by 
means  of  coaxial  cables  (of  the  telephone 
company)  or  by  radio  relay  (either  sup- 
plied by  the  telephone  company  or  other 
common  carrier,  or  else  established  by 
special  permission  of  the  FCC  as  the 
result  of  a  change  in  its  present  policy). 

Such  radio-relay  systems  consist  of  a 
number  of  repeater  stations  about  30 
miles  apart,  each  of  which  receives  the 
program  from  the  preceding  station  and 
automatically  carries  it  forward  to  the 
next  station.  These  relay  or  "booster" 
stations  may  be  unattended  and  subject 
only  to  occasional  inspection  and  the  re- 
placement of  expendable  material. 

In  brief,  those  considering  the  use  of 
radio  in  theatre-Tv  are  particularly  di- 
rected to  the  following  basic  points  which 
may  be  novel  to  those  not  familiar  with 
the  field  of  radio  communication. 

1.  Unlike  the  motion  picture  field,  Tv 
by  radio  is  subject  to  numerous  govern- 
mental regulations  and  controls.  Conse- 
quently, those  entering  theatre-Tv  and 
using  radio  transmission,  must  be  thor- 
oughly familiar  with  governmental  rules 
and  procedures  and  be  governed  thereby 
for  their  own  protection. 

2.  In  the  second  place,  Tv  by  radio 
requires  so-called  wide-channel  assign- 
ments by  the  FCC.  Such  channels  are 
scarce  and  much  sought.  Accordingly, 
nonuse  of  such  channels  almost  inevitably 
leads  to  their  pre-emption  by  others. 

3.  Accordingly,  if  theatre-Tv  is  to  secure 
such  radio  channels,  it  must  promptly 
request  their  assignment.  However,  a 
mere  request  is  not  generally  sufficient  to 
persuade    the    FCC    to    grant    channels. 


TYPICAL    DIRECT- PROJEC- 
TION SYSTEM  IN  THEATRE 

Optical  barrel  and  adjacent 
equipment  of  RCA-20th  Fox 
theatre  television  equipment 
located  on  hangar  immediately 
in  front  of  balcony  loge.  The 
cover  plate  of  the  lower  tube 
is  removed,  exposing  part  of 
the  high-voltage  current  supply 
unit.  Supplementing  this  unit 
and  installed  in  the  projection 
room,  is  an  equipment  rack  and 
control  panel  as  part  of  the  re- 
ceiving   terminal    unit. 


Usually  financial  responsibility,  definite- 
ness  of  construction  and  operating  plans, 
nature  of  ownership  and  affiliation,  will- 
ingness to  report  all  technical  (and  per- 
haps program)  progress,  and  other  obli- 
gations must  be  made  sufficiently  clear 
and  definite  to  justfy  the  assignment  of 
channels. 

There  seems  little  likelihood  that  a 
vague  expression  of  general  interest  or 
intent  will  lead  to  channel  assignments. 

4.  In  any  case,  even  an  otherwise  satis- 
factory application  for  channels  must  be 
denied  if  no  available  and  noninterfering 
channels  are  any  longer  existent,  be- 
cause of  prior  assignments.  The  conclu- 
sions to  be  drawn  are  evident. 

Projection  Systems:  Direct  Method 

Two  basic  systems  of  large-screen 
theatre-Tv  are  currently  being  evaluated 
in  this  country.  One  is  the  instantaneous 
or  direct  projection  system  by  which 
high-brilliance  cathode-ray-tube  images 
are  projected  by  means  of  an  efficient 
reflective  optical  system;  the  other  is  the 
storage  or  intermediate-film  system  using 
standard  motion  picture  projection  tech- 
nique, after  Tv  images  have  been  photo- 
graphed or  transcribed  on  motion  picture 
film  and  suitably  processed. 

Although  neither  type  is  commercially 
available  in  production  quantities,  the 
rapid  progress  of  the  art  warrants  de- 
scription of  equipment  in  experimental 
installations. 

The  direct-projection  system  consists 
of  three  major  optical  elements:  1.  the 
projection  cathode-ray  tube  which  is  the 
source  of  the  light  image;  2.  the  optical 
system  which  projects  the  image  into 
the  screen;  and  3.  the  screen  from  which 
the  final  image  is  viewed. 

In  addition  to  the  optical  elements  of 
the  system,  which  are  housed  in  a  pro- 
jection barrel,  the  electronic  auxiliaries 
include  a  control  console  containing  the 
associated  Ty  equipment,  and  a  power- 
supply  rack. 

The  cathode-ray  tube  used  in  the  di- 
rect-projection system  is  similar  to  the 
direct-viewing  tube  used  in  the  conven- 
tional receiver,  except  the  projection 
tubes  have  a  much  greater  light  output 
resulting  from  higher  voltage  operation 
for  which  they  are  designed. 

Since  available  Tv  for  commercial 
operation  is  not  adapted,  at  present,  to 
the  use  of  supplementary  light  sources 
as  are  motion  pictures,  the  brightness 
of  the  image  available  for  projection 
depends  upon  the  efficiency  of  the  cath- 
ode-ray tube  and  the  operating  poten- 
tials. An  average  picture  on  a  projec- 
tion tube  will  draw  a  beam  current  of 
approximately  1  milliampere  at  a  poten- 
tial of  80  kilovolts.  This  is  a  power  of 
(Continued  on  page  29) 


12 


INTERNATIONAL  PROJECTIONIST 


1 


March  1949 


Guardian  of  her  most  important  "bath"... 


COSTLY  shots  like  this  might  be 
so  much  spoiled  footage  .  . . 
save  for  the  vigilance  and  knowl- 
edge of  the  laboratory  man. 

He  makes  sure  that  the  dailies 
take  their  all-important  bath  ...  in- 
specting, testing,  keeping  constant 
check  as  the  exposed  footage  runs 
through  the  developing,  fixing,  and 
washing  tanks  and  driers. 

To  his  skill  and  watchfulness ...  as 


film  representing  "box-office  gold" 
literally  slips  through  his  careful  fin- 
gers .  .  .  motion  pictures  owe  much 
of  their  well-earned  reputation  for 
technical  excellence. 

This  skill  is  more  effective  .  .  .  the 
burden  of  constant  vigilance  lessened 
.  .  .  when  he  works  with  depend- 
able film  of  superior  quality.  That's 
why  he  always  welcomes  the  family 
of  Eastman  motion  picture  films. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.    Y. 

J.    E.    BRULATOUR,    INC.,    DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •     HOLLYWOOD 


Written  exclusively  for  IP,  this  presentation  constitutes  the  first  publication 
anywhere  of  written  and  graphical  data  anent  the  emergency  operation  of  the 
RCA  200  Series  sound  systems,  including   the  drive-in    theatre   equipment. 


Emergency  Operation 
of  Sound  Systems 

By  EDWARD  STANKO 

Theatre  Service  Division,  RCA  Service  Company 


FEW  events  are  more  upsetting  to  the 
projectionist  than  a  totally  unex- 
pected breakdown  of  a  serious  nature. 
For  example,  a  stripped  gear  in  a  pro- 
jector, or  a  sound  outage.  And  if  one 
happens  to  occur  just  when  the  house  is 
packed  (they  usually  happen,  somehow, 
during  just  such  propitious  occasions) 
life  for  him  can  be  a  pretty  strenuous 
affair.  Then  is  when  foresight  and  prep- 
aration can  pay  a  handsome  dividend. 

Mechanical  troubles  are  more  easily 
anticipated.  '  Many  parts  are  readily  ac- 
cessible for  inspection.  One  can  see 
what  condition  they  are  in.  With  elec- 
trical parts,  it's  different.  Outward  ap- 
pearance tells  little  about  the  remaining 
life  of  a  part  or  tube.  So  it's  more 
difficult  to  head  off  trouble  even  with  the 
best  of  "spit  and  polish"  routines.  Con- 
sequently, a  sound  failure  is  a  danger 
that  must  always  be  reckoned  with. 

But   this    need   not   necessarily   cause 

CHART  1.  EMERGENCY  OPERATION 
PG  230  OR  234  SYSTEMS 


MI-9253      RACK 


MONITOR    AMPLIFIER 
FUSE 

^.  ° 

'#'  2-AMR 

VOL.CONT. 


m 


PRE    AMPLIFIER 


EMERGENCY    SWITCH 
MON.SPKR 

NORMjfc  EMG.         *&* 

EMG.VOLUME 


POWER    AMPLIFIER 


FUSE 

O 
3 -AM  P. 


MI-9482  CROSSOVER 

fgj    ON    SPKR  NORM. 


MI-9358  POWER     AMPLIFIER 

,— .        (USED    WITH   PG-234   FUSE 
(D)  SYSTEM   ONLY)  O 

3-AMP. 


MI-9507  EXCITER    LAMP  SUPPLY 

EMG. 

:J2-amp. 


FUSES 


o  6-AMR 


every  projectionist  an  immense  amount 
of  concern.  For  many  are  operating 
sound  systems  in  the  design  of  which  the 
manufacturer  anticipated  just  such  situa- 
tions by  building  in  emergency  provisions 
of  various  sorts. 

Sometimes  these  provisions  take  the 
form  of  identical  dual  amplifiers.  Or 
they  may  be  means  for  by-passing  one 
of  the  amplifiers.  Or  the  form  of  a 
monitor-emergency  amplifier  which  can 
be  switched  in  to  carry  the  full  house 
load  when  necessary.  Or  provisions  for 
temporarily  operating  the  exciter  lamps 
from  a-c,  if  the  rectifier  for  supplying  d-c 
goes  out.  Or  a  switch  which  by-passes 
the  divider  network  so  that  the  full  tonal 
range  can  be  fed  into  the  low-frequency 
(1-f)  loudspeaker  in  the  event  of  trouble 
with  the  high-frequency  (h-f)  unit. 

Naturally,  there's  a  catch  in  this  too. 
The  projectionist  has  to  be  so  well  ac- 
quainted with  his  sound  system  and  its 
emergency  features  that  he  can  bring 
them  into  play  without  any  delays  of 
consequence. 

This  is  not  difficult  when  he  has  well- 
engineered  equipment.  Usually,  the 
manufacturer  can  supply  a  chart  showing 
the  emergency  switches,  etc.,  and  instruc- 
tions on  how  to  use  them.  And  the 
service  representative  is  willing  to  do  his 
share  toward  making  the  function  of  each 
perfectly  clear.  Of  course,  to  fix  the 
various  components  in  mind,  they  should 
be  practiced  over  and  over,  keeping  in 
mind  that  more  than  one  unit  can  be  out 
at  the  same  time  and  that  more  than  one 
emergency  feature  might  have  to  be  used 
to  restore  sound.  Then  when  the  pro- 
jectionist needs  to  avail  himself  of  one 
of  these  emergency  provisions,  he  can 
act  quickly  and  with  complete  confidence 
in  his  ability  to  make  the  right  moves. 

For  this  sort  of  situation,  RCA  Co., 
in  conjunction  with  RCA  Theatre  Equip- 
ment Sales,  has  prepared  a  series  of 
Emergency  Operation  Charts  for  RCA 
sound  systems  in  the  200  Series.  These 
systems  are  the  PG-230/234,  PG-240/ 
242/244/246,    and    PG-251    equipments. 


These  charts,  together  with  supplemental 
explanatory  notes,  are  published  herein. 

PG-230/234  SYSTEMS  (Chart  No.  1) 

These  two  systems  differ  only  in  that 
the  PG-234  has  two  output  amplifiers. 
Both  have  a  single  pre-amplifier  and  a 
special  high-gain,  monitor-emergency 
amplifier. 

Condition  1:  Amplifier 

When  the  Emergency  switch  on  Panel 
C  is  thrown  from  its  Normal  to  its 
Emergency  position,  the  monitor  ampli- 
fier on  Panel  A  is  switched  in  to  take  the 
place  of  both  the  pre-amplifier  on  Panel 
B  and  the  main  amplifier  (or  amplifiers) 
on  Panel  D.  When  this  is  done,  the 
volume  control  on  the  monitor  amplifier, 
Panel  A,  is  used  to  regulate  the  sound 
level  in  the  auditorium.  For  an  inde- 
pendent adjustment  of  the  monitor  vol- 
ume under  these  circumstances,  there  is 
a  Monitor  Speaker  Emergency  Volume 
Control  on  Panel  C. 

Condition  2:  Stage  Loudspeaker 

When  the  Emergency  switch  on  Panel 
E  is  thrown  from  its  Normal  to  its 
Emergency  position,  the  frequency  di- 
vider network  and  h-f  loudspeakers  are 
cut  out  of  the  circuit  and  the  entire  out- 
put range  is  fed  into  the  1-f  speaker.  In 
this  way  the  show  can  be  continued  quite 
satisfactorily  in  the  event,  the  h-f  loud- 
speaker goes  out  of  operation. 

Condition  3:  Exciter  Power  Supply 

When  the  switch  on  the  exciter  lamp 
supply,    Panel   F,    is   changed    from   its 

CHART  2.  EMERGENCY  OPERATION 
PG  240  OR  242  SYSTEMS 


M 1-9210- H  RACK 


MI-9328-A         VOLTAGE    AMPLIFIER 

0 


©~-E 


MI-9257-E         MONITOR    AMPLIFIER 
__  FUSE- 2  AMP. 

VOL.  CO  NT. 


MI-9384-C        EMERGENCY   SWITCH 

r-.  MON.SPKR. 

(CJ  NORM  ^  EMERG.      '^ 


EMER.VOL.CONT. 


MI-9302-D  COMPENSATOR 


MI-9354-D  POWER   AMPLIFIER 

,_,  o  FUSE- 3  AMP. 


MI-9475-A    CROSSOVER 


NORM. 
EMERG.   OFF 


ON 

8 


SPEAKERS 


MH9354-D  POWER    AMPLIFIER 

O  FUSE -3  AMP. 

(1)    (THIS  AMPLIFIER   USED  WITH 

PG-242    SYSTEM   ONLY) 


MI-9502-C         EXCITER    LAMP  SUPPLY 

EMER&  J&-  NORM, 
fg]  '     ^>*=}2AMRJ 


») 
fFUSE 

9  J 


14 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


Regular  to  its  Emergency  position,  low 
voltage  a-c  is  fed  to  the  exciter  lamps 
in  place  of  the  normal  d-c  power. 

PG-240/242  SYSTEMS  (Chart  No.  2) 
Condition  1:  Amplifier 

When  the  Emergency  switch  on  Panel 
C  is  thrown  from  its  Normal  to  its  Em- 
ergency position,  the  monitor  amplifier 
on  Panel  B  is  switched  in  to  take  the 
place  of  both  the  pre-amplifier  on  Panel 
A  and  the  main  amplifier  (or  amplifiers) 
on  Panel  E.  When  this  is  done,  the 
volume  control  on  the  monitor  amplifier, 
Panel  B,  is  used  to  regulate  the  sound 
level  in  the  auditorium.  For  an  inde- 
pendent adjustment  of  the  monitor  vol- 
ume under  these  circumstances,  there  is 
a  Monitor  Speaker  Emergency  Vol- 
ume Control  on  Panel  C. 

Condition  2:  Stage  Loudspeaker 

When  the  Emergency  switch  on  Panel 
F  is  thrown  from  its  Normal  to  its  Emer- 
gency position,  the  frequency  divider 
network-  and  h-f  loudspeakers  are  cut  out 
of  the  circuit  and  the  entire  output  range 
is  fed  into  the  1-f  speaker.  In  this  way 
the  show  can  be  continued  quite  satisfac- 
torily in  the  event  the  h-f  loudspeaker 
goes  out  of  operation. 

Condition  3:  Exciter  Power  Supply 

When  the  switch  on  the  exciter  lamp 
supply,  Panel  G,  is  changed  from  its 
Normal  to  its  Emergency  position,  low 
voltage  a-c  is  fed  to  the  exciter  lamps  in 
place  of  the  normal  d-c  power. 

PG-244/246  SYSTEMS  (Chart  No.  3) 

This  system  has  two  racks ;  but  the  a-c 


power  to  both  is  controlled  by  means  ot 
the  a-c  power  switch  on  Panel  G  (MI- 
9385)  of  the  MI-9231-B  rack.  The  sys- 
tem features  two  high-power  output  amp- 
lifiers which  are  operated  in  parallel  from 
the  voltage  and  intermediate  power 
amplifier  combination  used  in  a  PG-240 
system. 

Condition  7:  Voltage  or  Intermediate 
Power  Amplifiers 

When  the  Emergency  switch  on  Panel 
C  is  thrown  from  its  Normal  position  to 
its  Emergency  position,  the  monitor  amp- 
lifier on  Panel  B  is  switched  in  to  take 
the  place  of  both  the  voltage  amplifier  on 
Panel  A  and  the  intermediate  power  amp- 
lifier on  Panel  E.  When  this  is  done,  the 
volume  control  on  the  monitor  amplifier. 
Panel  B,  is  used  to  regulate  the  sound 
level  in  the  auditorium. 

An  independent  adjustment  of  the 
monitor  volume  level  under  these  circum- 
stances can  be  made  by  means  of  the 
Monitor  Speaker  Emergency  Volume 
Control  on  Panel  C. 

Condition  2:  Exciter  Power  Supply 

When  the  switch  on  the  exciter  lamp 
supply,  Panel  F,  is  changed  from  its 
Normal  to  its  Emergency  position,  low 
voltage  is  fed  to  the  exciter  lamps  in 
place  of  the  normal  d-c  power. 

Condition  3:  Output  Amplifier 

When  the  Emergency  switch  on  Panel 
H  of  the  MI-9231-B  rack  is  thrown  from 
its  Normal  to  its  Emergency  position, 
the  MI-9355-A  output  amplifiers  are  cut 
out  and  the  stage  loudspeakers  operated 
directly    from    the    intermediate    power 


CHART  3.    EMERGENCY  OPERATION  FOR  PG  244  OR  246  SYSTEMS 


©4L 


MI-9210-H    RACK 


MI-9328-A      VOLTAGE     AMPLIFIER 


® 


MI-9257-E        MONITOR    AMPLIFIER 
__  FUSE  -  2  AMR 

VOL.  cont. 


MI-9304-C        EMERG.    SWITCH 

C)  NORM.*EMRG.        MO^PKR 

emg.vol.cont. 


MI-9302-D 

® 


COMPENSATOR 


MI-9354-D      POWER    AMPLIFIER 
/— v  O  FUSE  -  3  AMR 


PANEL 


PANEL 


MI-9S02-C      EXCITER   LAMP  SUPPLY 
EMERG.  J^  NORM. 


i]2  AMR)f  USE 
5)6  AMP. J 


MI-9231-B    RACK 


M 1-9365 


A.C.  POWER- 


AC.  POWER  SWITCH 

OK1  (CONTROLS 

°?  BOTH 

JFILji  £\L.  RACKS) 

OFF 


EMERG.  SWITCH 
A   B 
NORM-Jk  EMERG 


MI-9475-A   CROSSOVER 
NORM 
EMERG 


ON 

8     SPKERS. 
OFF 


MI-9355-A 


POWER    AMPLIFIER 


O  3  AMP.Jf  usz 

O  6  AMR1 


PANEL 


Ml- 9355 -A        POWER    AMPLIFIER 

(THIS  AMPLIFIER  USED  WITH 

rrr\  PG-246  SYSTEM   ONLY) 

*— '  0  3AMP1 


O  6  AMP. 


}j=USE 


PANEL 


CHART  4.  EMERGENCY  OPERATION 
PG  251  SYSTEM 


Ml-92t2    RACK 


® 


MI-9389-A         MONITOR-EMERGENCY-SWrTCH 
NORM-0,""      .......... 

MONITOR 7^  A 

'■V?      EMG-2  o   o  •  •    .... 

B 
"VOLUME 


MI-9333  PRE-AMPLIFIER 


MI-9333 


PRE-AMPLIFIER 


POWER   AMPLIFIER 


t* 


8- AM  P. 

FUSE 

O 


TUBE  TEST 


® 


Ml-9359 


POWER   AMPLIFIER 


8-AMP. 
FUSE      _ 
<&      O       (M) 
TUBE  TEST 


amplifier  on  the  MI-9210-H  rack. 

Condition  4:  Stage  Loudspeaker 

When  the  Emergency  switch  on  Panel 
J  is  thrown  from  its  Normal  to  its  Em- 
ergency position,  the  frequency  divider 
network  and  h-f  loudspeakers,  are  cut 
out  of  the  circuit  and  the  entire  output 
range  is  fed  into  the  1-f  speaker.  In  this 
way  the  show  can  be  continued  quite 
satisfactorily  in  the  event  the  h-f  loud- 
speaker goes  out  of  operation. 

PG-251  DRIVE-IN  THEATRE 
SYSTEM  (Chart  No.  4) 

This  high-power,  drive-in  system  fea- 
tures two  complete  amplifier  channels 
mounted  on  a  single  rack.  Each  channel 
consists  of  a  pre-amplifier  and  a  special 
extra  high-power  output  amplifier.  The 
inputs  of  the  pre-amplifiers  always  re- 
main connected  in  parallel.  But  from 
that  point  on  the  two  channels  normally 
operate  independently  of  each  other,  with 
each  driving  one-half  of  the  in-car  loud- 
speakers. 

Condition  1:  Amplifier 

In  the  event  trouble  develops  in  one 
of  the  two  amplifier  channels,  the  entire 
speaker  load  can  be  transferred  to  the 
other  channel  simply  by  manipulating 
the  switch  on  the  MI-9389-A  panel.  When 
this  switch  is  turned  to  its  Emg-1  posi- 
tion, all  the  loudspeakers  of  Channel  2 
are  transferred  to  Channel  1  and  the  a-c 
power  is  shut  off  from  the  Channel  2 
amplifiers.  Similarly,  when  the  switch  is 
turned  to  Emg-2,  all  of  the  loudspeakers 
that  Channel  No.  1  normally  drives  are 


INTERNATIONAL  PROJECTIONIST 


March  1949 


15 


transferred  to  Channel  2  and  the  a-c 
power  is  shut  off  from  the  Channel  1 
amplifiers. 

In  either  case,  the  output  transformer 
tap  is  also  changed  automatically  when 
the  switch  is  thrown,  so  that  the  im- 
pedance matching  is  not  disturbed  by  the 
additional  speaker  load. 

The  monitor  loudspeaker  is  driven 
from  either  channel,  depending  upon  the 
position  of  the  selector  switch  imme- 
diately to  the  right  of  the  monitor  volume 
control.  Obviously,  when  the  Emercenci 
switch  is  turned  to  either  Emg-1  or  Emg-2, 
the  monitor  switch  also  must  be  flipped 
to  the  appropriate  position. 

General  Procedure  Hints 

Naturally,  whenever  a  projectionist  ex- 
periences a  sound  outage  with  any  sound 
system,  he  should  always  inspect  the  a-c 
line   fuses.      Moreover,   he   should   know 


exactly  where  these  fuses  are,  what 
ratings  are  normally  used  and  where  the 
spares  are  kept.  When  he  is  working 
under  pressure  during  an  outage,  it's  a 
poor  time  to  have  to  start  searching  and 
experimenting.  Fuses  are  particularly 
apt  to  blow  when  a  tube  in  the  exciter 
lamp  supply  or  one  of  the  larger  ampli- 
fier tubes  fails. 

Temporary  Character  Stressed 

Emergency  provisions  such  as  those 
described  should  always  be  regarded 
only  as  temporary  measures  for  restoring 
operation.  Just  as  soon  as  time  and 
circumstances  permit,  the  projectionist 
should  see  to  it  that  the  exact  source  of 
the  fault  is  located  and  remedied.  To 
this  end,  the  sound  service  representative 
should  always  be  notified  promptly  of  all 
symptoms  of  trouble. 


LETTERS    TO   THE    EDIT 


To  the  Editor  of  IP: 

Recently  your  Monthly  Chat  column 
mentioned  the  complete  disregard  of  film 
distributors  for  the  projectionist,  even 
though  the  latter  represents  the  interest 
of  their  customers,  the  theatres.  You 
were  concerned  then  with  the  quiet,  al- 
most secret,  manner  in  which  distributors 
sought  to  slip  acetate  prints  into  circula- 
tion. 

Later  you  compiled  and  brought  to  the 
attention  of  projectionists  a  list  of  film 
titles  due  to  be  issued  on  acetate  stock. 
You  also  published  a  scathing  denuncia- 
tion of  exchange  practices  in  general, 
with  particular  emphasis  upon  procedure 
in  the  issuance  of  acetate  prints. 

We  run  the  Fox  News  on  weekends. 
For  the  past  two  weeks  these  releases 
have  been  on  acetate  stock.  Needless  to 
say,  there  was  no  advance  warning, 
either  by  letter  or  by  a  notice  in  the  film 
can,  as  to  the  character  of  this  film.  The 
only  thing  out  of  the  ordinary  was  the 
receipt  of  these  prints  a  day  in  advance 
of  the  usual  schedule. 

Acetate  Splicing  More  Exacting 

Luckily,  we  have  been  using  all-pur- 
pose film  cement  for  some  time  now, 
thus  the  splicing  of  these  prints  occa- 
sioned no  difficulty.  However,  everybody 
is.  or  should  be,  aware  of  the  fact  that, 
despite  assurances  from  Eastman,  et  al, 
the  splicing  of  acetate  film  does  require 
more  care  than  does  nitrate  stock.  If 
this  film  had  arrived  at  the  last  moment 
(which  does  happen),  necessitating  a 
hurried  splicing  job,  any  ensuing  break 
would  have  meant  a  blasting  for  the  pro- 
jectionist. 

In  addition  to  warning  the  boys  about 


mmmmmm 

Fox  News,  it  seems  important  to  stress 
that  all  prints  are  now  suspect  and  re- 
quire inspection  to  establish  their  char- 
acter. 

Alfred  Revzin 
Kent  Theatre,  Bronx,  N.  Y.  (Local  306) 

The  following  communication  is  the 
reply  of  a  prominent  British  technician, 
who  asks  that  he  not  be  named,  to  a 
request  by  IP  for  data  relative  to  the 
progress  of  acetate  film  in  Great  Britain. 
To  the  Editor  of  IP: 

We  printed  on  acetate  stock  five  re- 
lease prints  of  two  features  and  sent  them 
around  the  circuit  on  a  special  route  but 
under  normal  circumstances.  The  major 
tests  covered  30  theatres — that  is,  three 
weeks — but  we  still  are  running  the 
prints  literally  to  death. 

We  have  a  fine  variety  of  equipment  in 
our  theatres,  both  old  and  new,  thus  the 
film  had  a  taste  of  everything.  Profiting 
from  all  the  data  published,  especially 
in  IP,  we  had  very  little  trouble. 

We  issued  specific  instructions  anent 
splicing,  together  with  supplies  of  the 
proper  cement.  The  boys  had  a  little 
trouble  at  first  in  removing  the  sub-base 
without  removing  all  the  base,  but  this 
difficulty  soon  cleared  up.  I  found  that 
a  good  splice  demands  the  use  of  a 
splicer,  the  hand  splices  lasting  only  a 
few  days.  So  we  supplied  the  theatres 
with  splicers. 

Splicer  Scraping   Block  Change 

This  brought  to  light  another  trouble 
wherein  the  splicer  scraping  block,  while 
good  enough  for  nitrate  film,  was  of  such 
design  that  when  attempts  to  remove  the 


sub-base  were  made  the  extra  pressure 
nearly  always  tore  the  perforations  to 
hell.  We  use  a  full-hole  positive  splice 
here,  as  projectionists  do  not  trust  the 
laboratory  join  known  here  as  a  "nega- 
tive" splice)  which  is  between  perfora- 
tions. 

My  personal  opinion  is  that  this  preju- 
dice developed  through  the  use  of  in- 
ferior cement  and  not  through  any  weak- 
ness of  the  splice  as  compared  with  the 
full-hole  splice. 

A  little  research  disclosed  that  the 
reed-type  scraper  was  the  ideal  thing; 
but  since  the  price  of  an  auto-splicer  is 
a  bit  beyond  our  reach  just  now,  and 
such  a  scraper  could  not  be  incorporated 
in  the  present  form  of  splicer,  I  tried 
again  and  managed  to  produce  a  rede- 
signed scraper  which  did  not  mean  modi- 
fication of  the  splicers  now  being  used 
and  manufactured.  I  obtained  the  official 
blessing  of  Kodak,  and  now  we  are  all 
happy. 

Now  I  am  messing  about  with  cements, 
as  I  think  we  do  not  yet  have  the  very 
best  binding  medium  possible.  Kodak 
has  made  up  several  different  grades, 
which  I  am  testing  in  the  field. 

Over-all  Performance  Satisfactory 

We  could  find  no  fault  with  acetate 
film  on  the  score  of  definition,  picture 
quality  or  sound  reproduction,  and  the 
stock  itself  has  stood  up  well  irrespective 
of  operating  conditions  or  equipment 
used.  While  acetate  film  would  appear 
on  the  basis  of  available  data  to  be  some- 
what inferior  to  nitrate  stock,  our  tests 
have  been  run  with  a  view  to  its  un- 
doubted great  advantages  in  use  no  less 
than  to  any  disadvantages  visible  to  or 
affecting  the  paying  patron. 

A  reel-by-reel  report  three  times  daily 
from  each  theatre  has  enabled  me  to 
compile  a  complete  history  of  all  acetate 
prints  from  the  moment  they  were  out 
into  circulation.  My  opinion  is  that  this 
stock  will  work  out  well,  provided  that 
we  do  a  little  educational  work  and  pro- 
vide the  proper  tools. 

IA     ELECTIONS 


LOCAL  257,  OTTAWA,  ONT ,  CANADA 

J.  McGuire,  pres.;  J.  Macauley,  vice-pres.; 
A.    B.    Zumar,    sec.-treas.;     Wm.    Hartnett, 
bus.  rep. 
LOCAL  424,  FALL  RIVER,  MASS. 

George  Sullivan,  pres.;  Charles  Proctor, 
vice-pres.;  Ray  Gagnon,  sec. ;  Jim  Cobryn, 
trcas. ;   Joe  Salvo,  bus.  rep. 

LOCAL  473,  WILMINGTON,  DEL. 

Leonard  Wright,  pres.;  E.  Bolinski.  vice- 
pres.;  H.  W.  Rouke,  Sr.,  sec;  Frank  Eckert, 
treas.;  John  R.  Waller,  bus.  rep.;  Phil  Jones, 
Louis  Longo,  John  Maisel,  Leo  McCarns, 
exec,  board. 


16 


INTERNATIONAL  PROJECTIONIST 


March  1949 


T-Number  vs.  F-Number  Lens  Markings 

Bearing  directly  on  several  aspects  of  the  preceding  article  by  R.  A.  Mitchell  is  the  ap- 
pended commentary  by  the  editor  of  The  British  Journal  of  Photography  anent  the  proposed 
substitution    of    T-numbers    for    the    time-honored    F-numbers. 


IT  IS  possible  that  the  majority  of 
people  have  not  heard  of  T-numbers, 
so  we  will  explain  what  they  are  and, 
first,  how  they  arise.  Nearly  everyone 
knows  that  when  light  falls  on  a  glass 
surface,  whether  it  be  plane  or  curved, 
a  certain  amount  of  light  is  reflected 
away  from  the  glass  and  thus  is  not  trans- 
mitted by  and  through  it. 

The  amount  of  light  so  lost  depends 
in  part  on  the  refractive  index  of  the 
glass,  but  still  more  on  the  angle  of  in- 
cidence of  the  light  onto  the  glass  sur- 
face. 

If  the  beam  of  light  is  at  right  angles 
to  the  plane  of  the  glass,  the  loss  by 
reflection  is  at  a  minimum;  whereas  if 
the  beam  approaches  at  an  acute  angle 
to  the  glass  surface,  the  loss  is  much 
greater,  and  it  increases  rapidly  as  this 
angle  becomes  more  pronounced.  That 
happens  at  any  glass-air  interface,  thus 
if  we  have  a  lens  built  up  of  several 
components,  as  is  usually  the  case  with 
modern  lenses,  then  losses  of  the  kind 
mentioned  will  occur  at  every  glass-air 
face,  and  the  aggregate  loss  of  light  will 
be  very  appreciable. 

Some  years  ago  it  was  dicovered  that 
if  the  glass  surface  could  be  treated  in 
such  a  way  to  provide  it  with  a  very 
thin  coating  of  a  substance  having  a 
refractive  index  equal,  or  nearly  equal, 
to  the  square  root  of  the  refractive  index 
of  the  glass,  and  ensure  that  the  coating 
should  be  ^4  wave-length  of  light  thick, 
then  the  loss  of  light  by  reflection  was 
very  much  less. 

In  fact,  in  a  lens  of  several  components 
it  might  well  happen  that  when  the  lens 
faces  were  so  treated  the  lens  would 
transmit  more  than  20%  additional  light. 
Such  treatment  of  lenses  is  now  a  normal 
commercial  procedure  by  many  impor- 
tant optical  instrument  manufacturers 
and  is  becoming  the  rule  for  good-quality 
lenses. 

Genesis  of  the  T-Number 

It  is  out  of  this  state  of  affairs  that 
the  F-number  has  arisen;  but  before  we 
discuss  its  importance  we  have  to  know 
what  relation  it  bears  to  our  old  friend 
the  F-number.  which  some  people  want 
the  F-number  to  supersede. 

We  assume  that  every  technician  knows 
that  the  F-number  of  a  lens  is  the  ratio 
of  the  focal  length  of  the  lens  to  its 
effective  diameter.  Thus,  if  a  lens  has 
a  focal  length  of  4  inches  and  admits  a 
beam  of  light  of  a  diameter  of  1  inch, 
we  say  it  has  a  relative  aperture  of  F:4. 


We  have  been  using  this  system  for  a 
very  long  time,  but  until  quite  recently 
have  never  paid  much  attention  to  the 
fact  that  it  was  quite  a  common  thing 
to  find  that  lenses  having  the  same  F- 
number  varied  measurably  in  speed. 
This  was  due  to  their  having  noticeably 
different  powers  of  transmitting  light. 
We  should  expect,  for  example,  a  single 
component  lens  to  transmit  more  light 
than  another  lens  of  identical  diameter 
but  made  up  of,  say,  four  components. 

When  it  was  found  that  by  coating,  or 
"blooming,"  lenses  they  could  be  made 
to  transmit  much  more  light — in  fact, 
from  20%  to  sometimes  as  much  as  33% 


— it  was  realized  that  a  system  of  lens 
marking  taking  this  factor  into  account 
would  be  of  value  to  certain  classes  of 
lens  users. 

Light-Transmitting   Power 

The  idea  was  to  have  a  F-number  scale 
in  addition  to  the  usual  aperture  ratio 
or  F-number  scale,  so  that  all  lenses,  no 
matter  of  what  make  or  aperture,  would 
have  the  same  light-transmitting  power 
when  the  diaphragm  was  set  to  the  same 
F-number  of  the  F-scale.  Such  a  F-scale 
would  be  engraved  in  a  series  similar  to 
that  adopted  for  the  F-numbers,  i.e., 
would  give  numbers  proportional  to  1, 
\/2,  2,  2\/2,  4,  and  so  on  as  required. 

Perhaps  the  essential  difference  be- 
tween the  F-number  and  the  F-number  is 
most  clearly  seen  when  the  definition  of 
the  F-number  is  given.  It  is  defined  as 
(Continued  on  page  27) 


ALTEC  MINI-MIKE  NO  LARGER 
THAN  STACK  OF  6  DIMES 

SMALLER  in  height  than  a  stack  of 
six  dimes,  and  even  smaller  in  circum- 
ference, the  new  Altec-Lansing  21-B  mi- 
crophone is  revolutionary  in  design  and 
embodies  exclusive  features  heretofore 
unobtainable  in  a  high-quality  micro- 
phone. Unprecedentedly  small  in  size — - 
it  weighs  less  than  *4  ounce — the  21-B 
covers  the  complete  audible  range  both 
as  to  spectrum  and  to  loudness. 

Adaptable  to  all  types  of  stand  mount- 
ings or  overhead  suspensions,  the  21-B 
is  so  inconspicuous  that  the  artist  or 
speaker  can  direct  his  entire  attention  to 
the  audience.  This  facility  was  a  funda- 
mental concept  of  the  microphone's  de- 
sign. 

Designed  on  Electrostatic  Principles 

The  21-B  is  designed  on  the  basis  of 
electrostatic  rather  than  magnetic  prin- 
ciples. The  only  moving  element  em- 
ployed therein  is  an  extremely  small  dia- 
phragm actually  no  larger  than  the  hu- 
man eardrum,  yet  the  sound  output  from 
this  tiny  apparatus  is  somewhat  greater 
than  from  conventional  microphones. 

Outstanding  among  this  unit's  features 
is  the  fact  that  it  is  blastproof,  thus  it  is 
not  necessary  to  protect  it  from  loud 
sounds  and  shocks  which  cause  extreme 
distortion  or  actual  damage  to  many  types 
of  microphones.  It  is  completely  non- 
directional,  or.  as  its  makers  term  it. 
"omni-directional."  It  is  no  longer  neces- 
sary for  performers  to  limit  their  speech 
to  the  "live"  side  of  a  microphone,  since 
the  Altec  microphone  is  "live"  on  all 
sides.  A  small  circumferential  sound 
channel  prevents  tonal  discrimination  at 
all  angles  from  the  sound  source. 

When  used  in  public  address  systems 
the  unusually  smooth  response  to  all  fre- 
quencies   makes     possible    as    much    or 


more  loudness  before  feedback  than  can 
be  obtained  with  directional  micro- 
phones. In  outdoor  use,  the  microphone's 
lack  of  susceptibility  to  changes  in  wind 
pressure,  and  its  freedom  from  "false 
bass  build  up"  when  used  close  to  sound 
sources,  enables  excellent  performance 
under  conditions  where  old-type  micro- 
phones produce  unbearable  noises. 

Special  Accessory  Mountings 

Altec  also  displayed  special  mount- 
ings for  sports  announcers,  consisting  of 
a  breastplate  weighing  a  few  ounces,  a 
lapel  clip  mounting  for  public  speakers, 
and  a  special  holder  designed  for  con- 
cealment in  television  and  motion  pic- 
ture sets.  Within  a  few  hours  after  be- 
ing demonstrated  to  a  select  group  of 
audio  engineers,  the  Altec  21-B  was 
placed  in  operation  on  the  stages  of  sev- 
eral of  New  York's  largest  motion  pic- 
ture presentation  theatres,  and  it  was 
also  adopted  for  general  use  by  the  an- 
nual convention  of  the  Institute  of  Radio 
Engineers. 

Graphical     evidence,     to     exact    scale,    of    the 

in-a-nutshell    character  of   the    new   Altec   21 B 

electrostatic-type  microphone. 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


17 


IN  THE 


SPOTLIGHT 


By 

HARRY 

SHERMAN 


pLSEWHERE  in  this  issue  appears  a  small  item  of  giant  significance  relating  to 
^the  payment  this  month  by  Eastman  Kodak  Co.  of  $13  million  in  wage  dividends. 
This  is  no  knuckling  to  "pressure";  on  the  contrary,  the  payment  represents  the 
37th  consecutive  annual  such  distribution  of  a  fixed  percentage  of  common  stock 
dividends.  This  item  set  up  a  train  of  thought  which  we  pass  along  herewith. 

First,  we  contrasted  this  item  with  the  statement  by  Atlas  Corp.,  investment  trust 
outfit  of  New  York  Ciy,  that  it  had  realized  $17  million  profit  from  its  "long-term 
investments  in  RKO."  This  display  of  the  absentee-ownership  power  of  the  dollar 
(a  mere  bookkeeping  transaction  requiring  not  a  sliver  of  manual  labor)  reflected, 
to  quote  Atlas'  own  statement,  an  average  return  of  more  than  20%  on  the  average 
annual  amount  invested  in  RKO."  Very  nice  going,  indeed,  for  those  dollar  share- 
croppers who  year  after  year  take  refuge  behind  the  "sound  national  economy" 
phrase  to  combat  a  minimum  wage  law. 

Second,  we  contrasted  the  Eastman  record  of  employe  benefits  with  the  first 
feeble  efforts  in  our  own  craft  to  establish  some  degree  of  worker  security.  The 
trail-blazing  achievement  of  Chicago  Local  110  in  establishing  an  employe-welfare 
plan  based  on  a  definite  mathematical  formula  is  merely  a  straw  in  the  wind,  pro- 
vided our  own  people  display  enough  foresight  to  profit  by  this  example. 

Eastman  Kodak  Co.,  with  a  record  $55  million  dollar  net  profit  for  1948,  cer- 
tainly is  not  in  need  of  any  pats  on  the  back  from  such  an  obscure  quarter  as  this 
department,  nor  are  these  few  words  intended  as  such.  Yet,  so  sharp  is  the  contrast 
between  the  Eastman  employe-benefit  record  with  the  dollar-grasping  attitude  of 
our  industry's  "leaders,"  that  we  felt  it  necessary  to  spread  these  few  words  upon 
the  record. 

Certainly,  too,  away  back  in  1912  there  was  nothing  in  the  social  structure  that 
compelled  George  Eastman  to  initiate  any  employe-benefit  program.  Keep  in  mind 
that  this  Eastman  wage  dividend  is  in  addition  to  the  usual  employe-benefit  plans 
adopted,  however  reluctantly,  by  all  progressive  business  enterprises —  life  insurance, 
sickness  insurance,  retirement  annuities,  social  security,  loan  provisions,  etc. 

Possibly  George  Eastman  builded  better  than  he  was  aware  of  37  years  ago.  But 
there  can  be  no  disputing  the  fact  that  he  recognized  the  dignity  of  Labor  and  sub- 
scribed to  the  principle  that  some  portion  of  the  dollars  accruing  to  any  business 
enterprise  should  go  to  those  whose  brain  and  hand  contributed  so  mightily  to  their 
making — the  worker.  Could  it  be  the  Eastman  policy  in  this  respect  was  a  vital 
factor  in  the  gigantic  success  attained  by  this  company? 


•  George  Schaffer,  former  business  agent 
of  Los  Angeles  Local  150,  was  tendered 
a  testimonial  dinner  by  a  group  of  Local 
150  members.  The  presentation  of  a 
beautifully  engraved  watch  came  as  such 
a  complete  surprise  to  George,  that  he 
was  rendered  speechless  —  no  mean 
achievement,  incidentally. 

•  At  a  recent  hearing  before  the  Senate 
Committee,  Charles  E.  Wilson,  president 
of  General  Electric,  made  the  following 
statement:  "I  can't  agree  that  there  are 
any  abuses  in  the  Taft-Hartley  Act.  I 
honestly  can't  find  them." 

We  think  that  Mr.  Wilson  would  have 
little  trouble  in  finding  many  abuses  in 
the  T-H  Act  if  he  were  sitting  on  the 
other  side  of  the  fence — if,  for  instance, 


he  were  in  the  position  of  a  projectionist 
who,  after  working  for  a  company  for 
four  years,  was  arbitrarily  dismissed 
from  his  job  because  one  of  the  "little 
executives"  of  the  firm  didn't  like  the 
way  the  projectionist  combed  his  hair 
or  tied  his  tie.  In  a  particular  case  where 
just  such  a  thing  occurred,  the  projec- 
tionist appealed  to  his  Local  officials,  but 
they  told  him  that  because  of  the  T-H 
law  "their  hands  were  tied,"  and  could 
do  nothing  for  him.  If  Mr.  Wilson  were 
that  projectionist,  he  would  inevitably 
find  plenty  of  abuses  in  this  anti-labor 
law. 

•  Film  supply  houses  in  the  Los  Angeles 
area  recently  agreed  to  a  20^-per-hour 
increase  for  their  projectionist  employes. 


This  is  getting  off  to  a  good  start  for 
Magnus  Nielsen  and  Earl  Hamilton, 
newly-elected  officials  of  Local  150. 

•  Larry  Davee,  sales  manager  for  Cen- 
tury Projector  Corp.,  was  the  guest 
speaker  at  a  recent  meeting  of  the  Inter- 
national Projection  Society,  the  members 
of  which  all  belong  to  Toronto  Local  173. 
Larry  was  scheduled  to  make  a  brief 
address,  but  his  talk  was  so  interesting 
and  informative  that  the  boys  refused  to 
let  him  off  the  rostrum  for  several  hours 
— and  then  he  had  to  beg  off. 

.'•  Among  the  visitors  to  IP  headquarters 
recently  were  the  too-long-absent  Herb 
Griffin,  vice-president  of  International 
Projector  Corp.;  George  Raaflaub,  secre- 
tary, and  Harry  Burley,  business  agent 
of  Syracuse  Local  376;  Clarence  Jalas, 
secretary  of  Chicago  Local  110;  and  that 
perennial  Texan,  the  best  National  Thea- 
tre Supply  Co.  branch  manager  in  New 
York  City,  Allen  Gordon  Smith. 

•  Bert  Sanford,  manager  of  theatre 
equipment  sales  for  Altec  Service  Co., 
was  appointed  vice-chairman  of  the  Mo- 
tion Picture  Committee  for  the  1949 
Catholic  Charities  Drive.  Not  only  has 
Bert  served  on  many  charity  drives,  but 
he  also  gives  unstintingly  of  his  time 
and  money  to  hardship  cases  that  come 
to  his  attention. 

Recently,  while  visiting  a  friend  in  a 
certain  hospital,  he  met  another  patient 
there  who  had  been  bed-ridden  for  the 
past  12  years.  Charitable  organizations 
closed  their  records  on  this  particular 
case  and  the  patient  was  very  despondent. 
Upon  hearing  his  story,  Bert  immedi- 
ately got  to  work  and  not  only  did  he 
have  this  man  transferred  to  another 
hospital  where,  for  the  first  time  in  12 
years,  he  is  responding  to  treatment,  but 
he  keeps  in  constant  touch  with  him  by 
means  of  frequent  visits  and  by  tele- 
phone, in  addition  to  generous  gift  pack- 
ages.   A  pretty  swell  guy! 

•  Coming  out  of  the  Masonic  Temple 
several  weeks  ago,  George  Raaflaub, 
Syracuse  Local  376,  fell  on  the  slippery 
pavement  and  broke  his  wrist.  Now 
pretty  well  on  the  mend,  George  is  seri- 


18 


INTERNATIONAL  PROJECTIONIST 


March  1949 


ously  considering  writing  a  book  on  how 
to  break  a  wrist  when  one  is  cold  sober. 
Should  be  very  illuminating — not  hallu- 
cinating. 

•  A  salary  increase  of  $4.50  per  week, 
on  a  40-hour  work  week,  for  more  than 
6,000  front-office  and  backroom  exchange 
workers  has  been  announced  by  the  IA. 
The  increases  are  retroactive  to  Decem- 
ber 1,  1948.  The  IA  negotiating  com- 
mittee, appointed  by  President  Walsh, 
comprised  Thomas  Shea,  assistant  Inter- 
national president;  Louise  Wright,  Inter- 
national vice-president,  and  Joseph  Bas- 
son,  International  representative. 

•  The  IA  seeks  no  quarrel  with  any  other 
labor  organization  in  the  Tv  field  and  it 
would  prefer  to  establish  harmony 
through  peaceful  negotiation.  The  main- 
tenance of  IA  jurisdictional  rights,  how- 
ever, is  of  paramount  concern  to  every 
IA  member  and  constitutes  the  corner- 
stone of  IA  negotiating  policy. 

This  was  the  statement  by  IA  Presi- 
dent Dick  Walsh  in  a  recent  news  con- 
ference for  both  the  trade  and  lay  press. 
IA  "jurisdictional  rights"  were  defined 
by  Walsh  as  those  -'earned"  through 
years  of  activity  in  show  business  as  well 
as  those  gained  by  organizing  along  well- 
defined  lines  since  the  advent  of  Tv. 
Walsh  was  impelled  to  call  the  press 
gathering  by  what  he  referred  to  as  the 
"threatening"  tone  of  press  releases  by 
the  National  Association  of  Broadcast 
Engineers  and  Technicians   (NABET). 

Citing  extended  futile  conferences 
with  NABET  in  an  effort  to  settle  Tv 
jurisdictional  lines,  Walsh  said  that  the 
expiration  on  April  30  next  of  contracts 
between  NABET  and  both  NBC  &  ABC 
Tv  networks  would  likely  touch  off  the 

TD^eW°rks""  An  aSreement  with  the 
IBEW  on  the  allocation  of  video  elec- 
tronic jobs,  and  the  fact  that  the  IA  even 
now  has  a  working  agreement  wtih  a 
NABET  local  chapter  in  Detroit,  was  evi- 
dence, said  Walsh,  that  the  IA  was  "leav- 


GUESTS  AT  LOCAL  521,  LONG  BEACH,  CALIF.,  39th  ANNIVERSARY  GET-TOGETHER 


Left  to  right:  Carl  Cooper,  IA  vice-president;  Herbert  Aller,  business  agent,  Hollywood  Local  659; 
Frank  Sawyer  and  George  Schaffer,  Los  Angeles  Local  150;  Roy  Brewer,  special  IA  representative. 


ing  the  door  wide  open"  for  future  peace- 
ful negotiation  and  had  no  intent  to  in- 
dulge in  any  "raiding  tactics  against  any 
legitimate  labor  group." 

It  was  gathered  from  Walsh's  remarks 
that  he  regarded  the  IA  entitled  to  juris- 
diction over  all  jobs  "in  front  of  the  Tv 
cameras,"  with  the  positive  inclusion  of 
both  projectionist  and  stagehand  jobs. 

•  We  regret  to  report  that  William  Doss, 
53,  charter  member  of  Syracuse  Local 
376  and  chief  projectionist  at  the  Eckel 
Theatre  for  the  past  30  years,  died  sud- 
denly last  month.  He  was  a  -member  of 
the  25-30  Club  and  of  Syracuse  Lodge 
No.  501,  F.  &  A.  M.  He  is  survived  by 
a  brother,  George,  and  a  nephew,  George 
E.  Doss,  both  members  of  Local  376. 

•  Hollywood  Local  705  (Costumers),  in 
negotiations  with  the  major  studios,  pro- 
posed that  a  10%  cut  on  all  reissues  be 
put  into  the  Local  pension  fund.  This 
proposal  is  now  being  considered  by 
studio  representatives  and  there  is  a 
strong  possibility  that  it  may  be  approved. 

•  Hugh  J.  Sedgwick,  business  agent  for 
Local  303,  Hamilton,  Ont ,  Canada,  and 
secretary   for   the   11th   District,   was   re- 


LOS  ANGELES  LOCAL  150  GROUP  HONORS  FORMER  BUSINESS  AGENT 


Committee  for  surprise  testimonial  dinner:    Don  McLaren,  'Pop'  Kenton,  Harold   Edinger,  Frank 
Sawyer,  George  Schaffer,  the  guest  of  honor;  Jim  Pointner  and  Walter  Preston. 


elected  secretary  of  the  Ontario  Provin- 
cial Federation  of  the  Canadian  Trades 
and  Labor  Congress.  Hugh  was  the  fra- 
ternal delegate  from  Canada  at  the  last 
AF  of  L  convention. 

•  A  record-breaking  attendance  marked 
the  27th  Anniversary  celebration  last 
month  of  Local  521,  Long  Beach,  Calif. 
The  dinner-dance  was  held  in  the  Star 
Room  of  the  popular  Hill  Top  Cafe. 
Among  the  out-of-town  guests  were  Carl 
G.  Cooper,  IA  vice-president;  George 
Abrams,  secretary  of  San  Diego  Local 
297;  William  Wise,  business  agent  of 
Local  297  and  president  of  California 
District  Council  No.  2.  Los  Angeles 
Local  150  was  represented  by  Earl  C. 
Hamilton,  president;  Magnus  Nielson, 
business  representative,  and  Hal  Huff. 

In  charge  of  arrangements  were  Paul 
King,  Alonzo  Bennett,  and  Everett  Cov- 
ington, all  of  whom  earned  the  vote  of 
thanks  extended  for  their  work  in  mak- 
ing this  one  of  the  most  enjoyable  par- 
ties ever  given  by  the  Local. 

Local  521  is  very  proud  of  the  work- 
ing conditions  enjoyed  by  its  members, 
such  as  the  6-day  week  (5-6  hour  work 
days)  ;  two-man  shift;  two-week  annual 
vacations  with  pay;  pay  for  daily  prep- 
aratory time;  excellent  sanitary  facili- 
ties, and  well-ventilated  projection  rooms. 
The  members  also  receive  hospitalization 
and  surgical  benefits,  and  weekly  sick 
benefits. 

The  eight  original  charter  members 
are  still  alive  and  active:  Alonzo  Ben- 
nett, William  Brown,  Donald  Dean,  Elliot 
Kirby,  Claud  Leyman,  Sr.,  Frank  Pe- 
trich,  Eugene  Tracy,  and  Arthur  Wiley. 

•  Edward  deVere  Maule,  member  of 
Hollywood  Local  165,  was  appointed 
chief  projectionist  at  the  Hollywood 
Paramount  Studios,  succeding  the  late 
Joseph  J.  Lynch.  Born  and  raised  in 
Philadelphia.  Ed  Maule  showed  an  early 
interest  in  electronics.  He  served  in  the 
(Continued  on  page  26) 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


19 


Total  Lumens  vs.  Screen  Light  Distribution 


GREAT  improvements  in  projection 
lighting  have  undeniably  been  in- 
stituted in  the  course  of  years.  "The 
record  of  progress,"  states  the  National 
Projector  Carbon  Handbook,  "shows  a 
10:1  improvement  in  the  brightness  of 
the  source,  a  30:1  improvement  in  effi- 
ciency of  screen  light  production,  and  a 
90:1  improvement  in  the  volume  of  light 
on  the  screen,  together  with  marked 
improvement  in  color  quality  and  steadi- 
ness." 

No  mention  is  made  of  progress  in 
screen  light  distribution,  however,  for 
there  has  been  none.  Indeed,  standards 
in  this  regard  have  slipped  so  badly  that 
the  writer  feels  impelled  to  voice  once 
more  the  fact  that  the  projection  craft  is 
being  unfairly  imposed  upon. 

'Hot  Spot'  Projection  Blight 

"Hot-spot"  projection  is  the  number- 
one  blight  on  the  efforts  of  conscientious 
projectionists  today.  Screen  illumination 
measurements  conducted  by  the  SMPE 
and  local  unions  reveal  that  fully  two 
thirds  of  the  total  number  of  theatre 
projectors  tested  provide  a  side-to-center 
screen  illumination  distribution  of  only 
from  50  to  75%.  It  is  impossible  to 
deliver  screen  results  any  better  than  the 
equipment   permits. 

In  an  optical  sense,  the  low-intensity 
(1-i)  carbon  arc  was  tailor-made  for  pro- 
jection purposes.  The  central  core  of 
the  positive  carbon  was  somewhat  less 
luminous  than  the  surrounding  shell  of 
hard  carbon,  a  condition  which  counter- 
acted to  a  large  degree  the  spherical 
aberration  of  the  elliptical  mirror  and 
the  unavoidable  vignetting  effect  of  the 
projection  lens.  (Projection  lenses,  even 
the  modern  F :   1.9  and  F:2.0  sizes,  are 


Record  Eastman  Earnings, 
Employee  Benefit  Payments 

Eastman  Kodak  Co.'s  net  earnings  in 
1948  were  $55,494,425  after  all  taxes 
and  charges,  equal  to  $4.45  per  share  of 
common  stock,  as  contrasted  with  a 
$3.64  per-share  payment  for  1947.  Sales 
during  1948  jumped  $83,644,528  to 
$435,395,626,  the  sales  increase  of  24% 
being  "largely  in  the  amateur  photo- 
graphic and  cellulose  product  fields." 

The  annual  report  revealed  that  mo- 
tion picture  film  sales  constitute  9%  of 
the  Eastman  total.  On  March  14  East- 
man paid  a  wage  dividend  of  $13  million 
to  about  50,000  employees  in  the  western 
hemisphere.  These  annual  dividends  are 
in  addition  to  regular  weekly  wages  and 
all  other  employee  social  benefits. 


By  MARK  STEVENS 

seldom  large  enough  to  be  considered 
truly  matched  to  the  lamp  optics.) 

The  inception  of  high-intensity  (h-i) 
light  sources,  far  superior  to  1-i  arcs  in 
light  volume  and  color  characteristics, 
introduced  a  brand  new  problem — one 
which  could  easily  be  solved  but  which 
responsible  quarters  have  chosen  to  ig- 
nore. The  central  portion  of  the  in- 
tensely luminous  ball  of  gas  held  in  the 
crater  of  the  h-i  positive  is  far  brighter 
than  its  edges.  This  causes  a  hot  spot 
to  be  part  and  parcel  of  the  image  of 
the  arc  on  the  aperture,  and  the  more 
perfectly  the  arc  image  is  focused,  the 
more  pronounced  is  the  hot-spot  effect. 

Needless  to  add,  this  inherent  hot  spot 
augments  the  vignetting  effects  intro- 
duced by  spherical  aberration  of  the 
condensing  element  and  lack  of  lens-lamp 
optics  match. 

Acceptable  Field  Illumination 

An  acceptably  uniform  field  of  illumi- 
nation may  be  obtained  by  throwing  the 
h-i  arc  slightly  out  of  focus — but  at 
what  a  cost!  The  loss  of  light  is  ex- 
ceedingly great,  and  an  undesirable 
bluish  color  is  introduced.  The  projec- 
tionist, therefore,  has  no  choice  but  to 
adjust  his  h-i  arc  so  close  to  the  position 
of  maximum  light  production  that  a  de- 
cided hot  spot  mars  the  beauty  of  the 
picture. 

Let  nobody  disparage  the  technological 
astuteness  of  the  projectionist.  Projec- 
tionists know  what  they  want  in  the  way 
of  screen  results,  and  they  not  infre- 
quently come  forth  with  suggestions 
which  can  readily  be  shaped  up  for  the 
factory  and  incorporated  into  commercial 
equipment  units.  And  99%  of  these 
suggestions  are  offered  free  of  charge! 

Out  and  out  "boners"  in  equipment 
design  most  certainly  do  occur.  All  of 
us  make  mistakes,  and  for  that  reason, 
if  for  no  other,  minor  miscalculations  are 
forgiveable.  But  a  blatant  disregard  of 
projectionists'  requirements  is  the  unfor- 
givable sin,  and  it  is  high  time  for  the 
craft  to  arouse  the  self-satisfied  by  a 
searching  investigation  into  the  why's 
and  wherefore's  of  each  new  unit  offered 
in  a  confusing  fanfare  of  ballyhoo. 

Promotional  Tactics  Questioned 

The  promotion  of  projection  lamps 
not  infrequently  follows  the  selling  line 
heretofore  confined  to  the  toothpaste  and 
kitchen-soap  businesses.  All  too  often 
there  are  frenetic  attempts  to  dazzle  the 
craft  with   a  superabundance   of  lumens 


and  to  high-pressure  the  projectionist 
into  abandoning  all  standards  of  quality 
light  production  in  favor  of  quantity. 
Studiously  omitted  is  an  honest  appraisal 
of  light  quality  and  distribution  on  the 
screen. 

Projectionists  are  not,  as  a  rule,  swept 
off  their  feet  by  ecstatic  hoopla  that  a 
lamp  projects  X-thousand  lumens  to  the 
screen  when  drawing  only  Y  amperes, 
however  intriguing  this  information  may 
be.  Other  factors  are  involved.  "What 
about  the  side-to-center  distribution  of 
light  on  the  screen  under  average  condi- 
tions?" the  projectionist  asks;  and  the 
manufacturer  grudgingly  divulges  the 
none-too-flattering  information  previously 
kept  under  wraps.      (Naturally!) 

What  could  possibly  be  the  color 
characteristics  of  the  light  output  of  a 
lamp  advertised  as  producing  a  greater 
proportion  of  visible  wavelengths  than, 
presumably,  any  other  high-intensity 
lamp?  The  idea  prompting  this  intelli- 
gence is  that  heat  filters  are  unnecessary. 
Now,  all  of  us  know  that,  in  comparison 
with  1-i  lighting,  the  light-curve  of  all 
h-i  carbon-arc  sources  falls  off  rather 
sharply  in  the  infra-red  region,  and  that 
no  wave-length  of  visible  light  can  exactly 
be    described    as    "cold."      And   yet    no 


SMPE  65th  Convention  Set 
for  New  York,  April  4-8 

The  65th  semi-annual  convention  of 
the  Society  of  Motion  Picture  Engineers 
will  be  held  at  the  Hotel  Statler  (for- 
merly the  Hotel  Pennsylvania),  in  New 
York,  April  4  to  8,  inclusive.  Reports 
and  demonstrations  of  the  latest  develop- 
ments in  theatre  television  and  high- 
speed photography  will  be  the  subjects 
of  special  sessions  and  symposia  during 
the  first  three  days  of  the  convention, 
announced  Earl  I.  Sponable  (20th  Cen- 
tury-Fox)   President  of  the  Society. 

With  theatre  Tv  rapidly  approaching1 
the  commercial  stage  and  other  technical 
facilities  of  the  motion  picture  industry 
undergoing  intensive  laboratory  develop- 
ment, a  major  concentration  of  leading 
engineers  is  expected  at  the  convention 
to  participate  in  a  rich  variety  of  tech- 
nical sessions. 

William  H.  Rivers,  chairman  of  the 
Atlantic  Coast  Section,  is  in  charge  of 
local  arrangements,  and  William  C. 
Kunzmann,  convention  Vice  President, 
will  supervise  registration  and  informa- 
tion for  the  meetings. 


20 


INTERNATIONAL  PROJECTIONIST 


March  1949 


figures  are  given  to  support  the  assertion. 

"The  largest,"  "the  higgest,"  etc.,  are 
terms  calculated  to  impress  those  scarcely 
capable  of  counting  on  their  fingers,  but 
a  little  careful  consideration  never  fails 
to  prick  the  inflated  bubble  of  such 
hokum.  When  such  grandiose  superla- 
tives are  applied  to  lamp  collector  ele- 
ments— mirrors  or  condensers — they  may 
mean  nothing  but  a  bulky  projection 
set-up.     For  example: 

A  16-inch  mirror  operating  34  inches 
from  the  projector  aperture  has  a 
"spurious,"  or  geometric,  speed  of  F:2.1. 
A  6-inch  condensing  lens  the  converging 
element  of  which  operates  12  inches  from 
the  aperture  has  a  speed  of  F:2.0,  and 
hence  is  just  a  trifle  faster  than  the  large- 
size  mirror.  When  the  masking  effect  of 
carbon  supports  is  considered,  it  will  be 
seen  that  the  condensing  lens  is  appre- 
ciably more  efficient  than  the  very  much 
larger  mirror. 

Consideration  of  mirrors  again  brings 
the  matter  of  hot-spot  projection  to  our 
attention.  We  have  a  right  to  ask,  in 
view  of  the  different  light-production 
characteristics  of  low-  and  high-intensity 
arcs,  whether  the  mirror  in  any  reflector- 
type  lamp  is  conventially  elliptical,  or 
whether  it  is  over-parabolized  to  compen- 
sate for  the  hot-spot  nature  of  the  h-i 
gas  ball. 

Side-to-Center  Screen  Distribution 

No  matter  how  efficient  any  lamp  may 
be  in  respect  to  economy  of  operation,  a 
side-to-center  distribution  of  screen  illu- 
mination of  only  65%  is  sufficient  reason 
for  rejecting  it.  A  fall-off  of  35%  in 
illumination  at  the  edges  of  the  screen  is 
intolerable  where  high  projection  stand- 

Iards  are  maintained.  Many  h-i  lamps, 
large  and  small,  have  the  same  deplorable 
defect. 
It  may  be  supposed  that  very  careful 
adjustment  of  the  arc-mirror  distance  will 
decrease  the  illumination  fall-off  to  only 
20% — a  side-to-center  distribution  of 
80%.  In  this,  however,  we  are  giving 
any  lamp  the  benefit  of  a  doubt.  We 
merely  "assume,"  on  the  basis  of  experi- 
ence with  other  h-i  lamps,  that  we  could 
bring  the  side-to-center  distribution  up 
to  80%  and  thus  "get  by"  after  a  fashion, 
even  though  we  are  still  dissatisfied  with 
screen  results.  Even  so,  we  cannot  escape 
sacrificing  many  thousands  of  screen 
light  lumens. 

Reliable  data  issued  by  National 
Carbon  Co.  indicate  that  screen  lumens 
will  be  decreased  by  approximately  21% 
when  we  bring  side-to-center  light  dis- 
tribution up  from  65%  to  80%.  For 
more  uniform  light  distribution — sup- 
posing that  working  distance  and  mirror- 
arc  distance  could  be  finagled  to  effect 
such  a  result — the  efficiency  of  the  lamp 
would  be  disastrously  reduced,  and  we 
would    have    been    better   off   if   we    had 


National  Carbon  Co.  Releases  Data  on  9-mm  H-I  Carbon 


FOR  some  time  now  there  has  been  in 
use  in  scattered  localities  a  9-mm  high- 
intensity  projector  positive  carbon  for 
use  in  reflector  type  motion  picture  pro- 
jectors. This  carbon,  of  the  "bare"  type 
— that  is,  without  the  copper  coating 
typical  of  Suprex  carbons — is  20  inches 
long  and  is  used  with  a  5/16-  by  9-inch 
Orotip  cored   negative. 

Performance  data  anent  this  carbon 
trim  has  been  lacking  previously,  Na- 
tional Carbon  Co.  evidently  holding  that 
insufficient  time  had  elapsed  to  regard 
this  trim  in  other  than  the  experimental, 
or  field-testing,  stage,  and  no  data  was 
included  even  in  the  Projector  Carbon 
Handbook   recently   published. 

Values  for  this  combination  burned  in 
an   angular  trim  with  a  rotating  positive 


SCREEN  ILLUMINATION  TABLE 

9-mm  H-I  Carbon,  Angular  Rotating  Trim 

Positive   Carbon  9  mm  x  20"  H-I1 

Negative   Carbon  5/16  x  9"  Orotip 

Arc  Amperes  85 

Arc  Volts  58 

Lamp  Optics  F:2  Reflector 

Projection  Lens  5"  F:2  Coated 

Screen  Light  Distribution: 
80%  Side-to-center3 

Total  Screen  Lumens2  15,400 
Ft. -Candles,   Center  of  Screen4 

Screen  Width  of         20  Ft.  30.0 

25  Ft.  19.1 

30  Ft.  13.2 

Maximum  Light3:  Screen  Light 

Distribution  of  55% 

Side-to-center3 

Total  Screen  Lumens2  19,500 
Ft. -Candles,   Center  of  Screen* 

.Screen   Width   of         20  Ft.  45.5 

25  Ft.  29.0 

30  Ft.  20.3 

1Heat  filters  may  be  necessary  with  this 
arc.  Light  values  will  be  reduced  approxi- 
mately 20%  if  "Aklo"  or  phosphate  glass 
is  used. 

2  Figure  is  for  systems  with  no  shutter, 
film  or  filters  of  any  kind. 

3  Refers  to  ratio  of  light  intensity  at  side 
of  screen  to  that  at  center. 

4 Foot-candle  values  at  center  of  screen 
assume  50%  shutter  transmission,  with  no 
film  or  filters  of  any  kind. 

'Value  with  system  adjusted  to  produce 
maximum  light  intensity  at  center  of  screen. 


carbon  in  an  F:2.0  reflector  and  projec- 
tion system  have  now  been  established, 
as  shown  in  the  accompanying  table. 
National  Carbon  emphasizes  that  these 
data  were  obtained  by  the  same  methods 
and  are  subject  to  the  same  qualifications 
as  described  in  the  SMPE  paper  en- 
titled "Screen  Illumination  with  Carbon 
Arc  Motion  Picture  Projection  Systems" 
published  in  the  SMPE  Journal  for 
January,   1947. 

Similarly,  the  data  as  set  forth  are  in 
the  same  form  and  might  be  considered 
as  supplementary  to  Tabic  V  on  page  45 
and  Table  VII  opposite  page  62  of  the 
National  Carbon  Handbook.  Projection- 
ists likely  will  wish  to  add  this  informa- 
tion in  printed  form  to  their  copies  of 
the  Handbook. 

Strikingly  apparent  in  the  accompany- 
ing table  is  the  profound  influence  of 
the  percentage  of  side-to-center  screen 
light  distribution  upon  total  light  lumen 
production  on  the  screen  and  particu- 
larly at  the  center.  IP  readers  will  recog- 
nize in  these  data  .a  validation  of  the 
information  presented  previously  in  these 
pages  in  articles  on  projection  optics, 
and  especially  in  the  article  "Total 
Lumens  vs.  Screen  Light  Distribution" 
in  this  issue    (p.  20). 

Side-to-Center  Distribution  Factor 

For  example,  the  table  shows  that  a 
projection  system  designed  to  provide 
an  80%  side-to-center  light  distribution 
produces  maximum  light  of  15,400 
lumens;  whereas  a  system  providing  a 
55%  light  distribution  produces  maxi- 
mum light  of  19,500  lumens. 

The  significance  of  these  figures  will 
at  once  become  apparent  to  any  ex- 
perienced projectionist,  who  understands 
perfectly  that  the  production  of  an  in- 
tense center  hot-spot  at  the  expense  of 
illumination  in  other  sectors  of  the  screen 
falls  far  short  of  recognized  motion  pic- 
ture  projection  standards. 

Moreover,  to  all  except  those  purists 
in  the  craft  who  consider  90%  or  better 
the  only  proper  side-to-center  light  dis- 
tribution standard,  80%  is  recognized  as 
an  acceptable  distribution  of  the  total 
light  available. 

Over-all,  such  figures  as  are  presented 
in  the  accompanying  table  focus  atten- 
tion upon  that  most  vital  consideration 
in  any  discussion  of  values,  whether  the 
topic  of  interest  be  projection  screen 
light  or  wage  scales.  That  most  im- 
portant consideration  is  "under  what 
conditions"  is  a  given  value  attained. 


kept  on  with  the  older  h-i  lamp  which  we       Suprex  positive  and  a  7-mm  Orotip  nega- 

discarded.  tive   at   70  amperes  will   produce   13.000 

A  simplified  h-i  lamp  using  an  8-mm       screen  lumens  with  an  80%  side-to-center 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


21 


light  distribution  under  the  conditions  of 
a  5-inch  F:2.0  coated  projection  lens. 

Mere  light  production  no  longer  im- 
presses us.  Thanks  to  the  unceasing 
efforts  of  carbon  makers,  lumens  are 
relatively  cheap  today.  What  is  not  so 
easily  had,  however,  is  good  illumination 
distribution  on  the  screen.  The  task  of 
designing  lamps  capable  of  producing 
uniform  screen  illumination  without  un- 
due light  loss  is  squarely  up  to  the  manu- 
facturers of  mirrors  and  lamps. 

Ideal  Side-to-Center  Coverage 

The  writer's  personal  opinion  is  that 
no  side-to-center  screen  illumination  dis- 
tribution under  95%  can  be  considered 
satisfactory,  and  he  is  confident  that  all 
discriminating  projectionists  concur  in 
this  opinion.  Naturally,  the  side-to-cen- 
ter distribution  should  not  in  any  case 


exceed  100%,  for  that  would  be  a  serious 
error  in  the  other  direction.  Arbitrarily 
adopted  as  the  optimum,  then,  is  95%. 

Now,  a  distribution  as  uniform  as  this 
absolutely  can  be  effected  without  undue 
light  loss  by  designing  mirrors  to  pro- 
duce it.  This  means  that  the  image  of 
the  h-i  arc  on  the  aperture  must  be 
deliberately  distorted  to  smooth  out  the 
high  central  illumination;  and,  further, 
the  "compensation"  must  actually  be 
overdone  to  the  extent  necessary  to 
counteract  the  vignetting  effect  of  the 
projection  lens. 

Until  progress  in  screen  light  distribu- 
tion goes  forward  instead  of  backward, 
the  writer,  for  one,  cannot  wax  enthusi- 
astic over  lamps  which,  as  performance 
is  measured,  merely  repeat  those  errors 
which  have  been  with  us  all  too  long. 


An  Exhibitor  Assays  Tv  as  Movie  Theatre  Competition 


TELEVISION  will  prove  "very  rough 
competition"  for  film  theatres  to  meet, 
and  the  competition  in  the  event  video 
has  access  to  the  same  product  as  theatres 
will  be  fatal  to  the  latter,  in  the  opinion 
of  Leo  F.  Wolcott,  board  chairman  of 
the  Allied  ITO  of  Iowa  and  Nebraska. 

Wolcott,  who  declares  that  the  tele 
question  confronts  exhibitors  "two  years 
ahead  of  schedule,"  summarizes  his  find- 
ings after  a  study  of  Tv  in  the  current 
bulletin  to  the  unit's  members.  His  con- 
clusions follow: 

"Just  because  movie  theatres  have  been 
here  'as  far  back  as  I  can  remember'  is 
no  sound  basis  for  blind  belief  they'll 
always  be  here.  The  stage,  and  par- 
ticularly vaudeville,  were  here  for  ages 
— until  pictures  came  and  talking  pic- 
tures wrote  'finis'  to  them  both,  except 
in  the  large  cities. 

"Apparently,  Tv  experience  to  date  has 
proven  motion  pictures  its  best  medium 
due  to  ease  of  handling  finished  prod- 
ucts, scope,  definite  running  time,  and 
other  factors.  Accordingly,  it  is  evident 
the  effort  will  be  made  to  channel  more 
and  more  movies  to  Tv. 

"Comes  now  the  question:  will  movies 
on  Tv  put  movie  theatres  out  of  business? 
It  seems  to  me  that  depends  upon 
several  factors,  the  most  important  of 
which  naturally  is  the  return  which  can 
be  had  for  the  producers  of  the  pictures. 

Tv  Equipment  Cost  Prohibitive 

"First  of  all,  let  it  be  said  here  and 
now  that  the  many  thousands  of  small 
theatres  cannot  hope  to  install  Tv  equip- 
ment at  $35,000  to  $50,000  in  the  im- 
mediate or  forseeable  future.  Yet  these 
U.  S.  theatres  are  and  will  remain — un- 
less they  are  allowed  to  go  under  from 
the  impact  of  Tv— the  main  and  best 
source  of  revenue  for  the  picture  pro- 
ducers,  a    source    which    cannot    be   re- 


placed or  duplicated.  Obviously,  people 
are  not  going  to  theatres  and  pay  50c 
admission  for  the  same  show  they  can 
get  on  Tv  at  home  for  free. 

"And  let  us  not  kid  ourselves  about 
man  being  such  a  sociable  creature  that 
he  just  must  go  out  to  the  movies  at 
regular  intervals.  The  beginning  days 
of  radio  disproved  that  old  gag:  the 
people  got  together  in  each  other's 
houses,  mixed  up  some  cocktails  and 
sat  and  listened  to  the  Two  Black  Crows, 
Amos  and  Andy,  Fibber  McGee  and 
Molly  and  the  other  programs  of  those 
days. 

"It  was  bad  enough  for  three  years 
then;  now  Tv,  with  sound  and  sight,  will 
prove  very  rough  competition  for  the 
theatres  to  meet,  and  fatal,  if  Tv  has 
access  to  our  merchandise,  our  pictures. 
It  is,  of  course,  conceivable  that  short 
trailers  of  currently  theatre-released  pic- 
tures shown  on  Tv  would  prove  feasible, 
and  of  advantage  to  theatres,  but  not  the 
full  picture." 


An  11 -ounce  Radio  Station 

A  radio  receiver  and  transmitter  as 
small  as  a  king-size  package  of  cigaretes 
has  been  developed  by  the  U.S.  Army 
Signal  Corps.  This  tiny  radio  "station," 
weighing  11  ounces,  will  transmit  and 
receive  spoken  messages  over  distances 
of  more  than  200  yards.  It  is  believed 
to  be  the  only  radio  in  the  world  that 
contains  in  one  package  all  the  necessary 
parts,  including  power  supply. 

The  miniature  "transceiver"  includes 
batteries,  a  two-foot  collapsible  whip  an- 
tenna, four  tubes  and  other  parts,  all 
contained  in  a  tiny  metal  case  1  inch 
thick,  21/4  inches  across  the  base,  and 
3^/2  inches  high.  The  set  has  a  built-in 
speaker  and  a  mike,  and  the  batteries 
have  a  life  span  of  14  hours. 


Simplex  In-a-Car  Speaker's 
Many  Redesign  Features 

The  Simplex  In-a-Car  speaker  has  been 
redesigned.  The  speaker  case  is  diecast, 
using  a  lightweight,  "tough  as  steel"  alu- 
minum alloy.  The  bare  casting  is  first 
phosphated  to  protect  it  against  oxidation 
and  to  provide  a  tough  undercoating  for  the 
lacquer  finish.     The  entire  finish  is  highly 


The  new  Simplex  In-a-Car  speaker. 

resistant  to  peeling,  chipping  or  blistering. 
Drain  holes  are  adequate  to  empty  all  con- 
densation or  rain  water  from  the  interior 
of  the  case. 

A  G.E.  4-inch  p.m.  aluminum  voice  coil 
speaker  unit  is  standard  equipment.  Con- 
ventional speaker  units  employ  a  paper-base 
voice  coil,  and  the  best  of  weatherproofing 
will  not  keep  all  water  out.  Any  water  that 
enters  the  coil  mounting  causes  it  to  ex- 
pand and  rub  against  the  magnet.  The  alu- 
minum coil  mounting  is  not  affected  by  heat 
or  dampness  and  will  not  change  shape.  A 
heavy  Alnico  V  magnet  assures  high  effi- 
ciency. 

A  push-button  switch,  controlling  the  con- 
cession signal  on  the  coupling  unit,  is 
mounted  directly  below  the  volume  control 
knob,  permitting  signalling  by  flashing  on 
a  light  in  the  coupling  unit.  The  signal 
switch  is  optional  equipment.  Coupling  units 
may  be  purchased  without  lamps,  sockets 
or  wire  form,  but  with  provision  for  them 
if  it  is  desired  to  add  lights  later. 

New  Method  of  Speaker  Mounting 

A  unique  method  of  speaker  mounting 
reduces  to  a  minimum  the  number  of  speak- 
ers thrown  out  of  cars  on  the  ground.  On 
conventional  coupling  units  the  basket  is 
directly  in  line  with  the  unit.  On  a  dark 
night,  the  patron  cannot  see  the  basket 
because  it  blends  in  with  the  coupling  unit 
housing.  The  Simplex  design  swings  the 
baskets  back  at  an  angle  so  that  the  patron 
can  see  the  basket  in  silhouette.  Two  coat- 
ings of  neoprene  are  vulcanized  to  the  bas- 
ket forms  to  provide  a  tough,  durable  finish, 
impervious  to  weather  conditions. 

The  terminal  strip  is  designed  for  all  com- 
mon electrical  connections.  The  electrician 
may  use  pliers,  wrenches  or  a  screw  driver 


22 


INTERNATIONAL  PROJECTIONIST 


March  1949 


to  lock  down  the  fastening  nuts  on  the 
terminal  bolts,  each  of  which  is  threaded 
into  the  strip  so  that  it  cannot  turn  when 
external  connections  are  being  made. 

Details  of   Transformer  Construction 

A  vacuum-impregnated  matching  trans- 
former is  hung  under  the  terminal  strip,  out 
of  the  way  at  all  times.  No  wax  or  rub- 
ber coating  is  applied  to  the  transformer, 
since  this  is  a  very  ineffective  method  of 
waterproofing.  Instead,  every  transformer  is 
placed  in  a  vacuum  cell,  and  when  all  of 
the  air  has  been  removed,  a  special  weather- 
proofing  material  is  injected  which  pene- 
trates all  exterior  and  interior  surfaces.  The 
coating,  unlike  wax  or  rubber,  cannot  break 
or  crack  and  weatherproofs  the  transformer 
indefinitely. 

A  large,  heavy-duty  cable  clamp  is  pro- 
vided in  each  coupling  unit  to  firmly  clamp 
the  outside  covering  of  the  speaker  cable. 
This  prevents  damage  to  the  terminal  strip 
should  a  patron  inadvertently  drive  away 
with  the  speaker  in  his  car.  Adequate  ven- 
tilation means  are  provided  to  permit  rapid 
evaporation  of  condensation  forming  inside 
the  unit. 


Precision-Formed  Filaments  on 
New  G.  E.  Projection  Lamps 

Brighter  and  surer  screening  of  mo- 
tion pictures  is  available  to  users  of 
8-  and  16-mm  projectors  as  a  result  of 
a  major  improvement  in  the  construc- 
tion of  movie  projection  lamps.  General 
Electric  engineers  revealed  that,  after 
years  of  effort,  they  had  heen  successful 
in  devising  a  method  of  forming  me- 
chanically the  complex  filaments  used  in 
the  projection  lamps. 

Precision  forming  of  the  filaments  has 
resulted  not  only  in  improved  screen 
illumination  initially,  but  also  in  better 
light  maintenance  during  life,  according 
to  the  engineers.  They  said  the  im- 
proved projection  lamps  also  give  more 
uniform  performance  than  those  with 
hand-formed  filaments,  there  being  less 
variation  from  the  average  in  the  life  of 
individual  lamps. 

Output  is  Greatly  Expanded 

Previously,  engineers  explained,  the 
difficult  and  tedious  task  of  forming  the 
filament,  which  contains  10  separate  coils 
of  fire  tungsten  wire,  was  accomplished 
by  girls  selected  especially  for  their 
aptitude  for  this  type  of  work.  After 
many  months'  experience,  a  skilled  girl 
was  able  to  form  filaments  for  only  about 
80  projection  lamps  daily. 

Lamps  involved  in  the  new  construc- 
tion include  a  500-watt  lamp,  No. 
500T10P,  having  a  rated  burning  life  of 
25  hours,  for  use  in  8-mm  movie  pro- 
jectors; a  750-watt  lamp,  No.  750T12P, 
rated  at  25  hours,  for  use  in  both  8-  and 
16-mm  projectors ;  and  a  1000-watt  lamp, 
No.  1MT12P,  rated  at  10  hours,  for  use 
in  16-mm  mechanisms. 


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COATED 
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WHY  ARE  SHORT  FOCAL  LENGTH  LENSES  USED  FOR  DRIVE-INS? 
Where  the  projection  room  must  be  located  near  the 
screen,  short  focal  length  lenses  are  necessary  to  proj- 
ect large  pictures.  For  this  reason  lenses  with  focal 
lengths  from  2"  to  3l/z"  are  usually  used  in  Drive-Ins. 
The  Kollmorgen  Screen  Chart  shows  the  focal  length 
needed  for  pictures  from  9  to  85  ft.  wide  at  40  to  400  ft. 
throws. 


DO     SHORT 
PICTURES? 


FOCAL     LENGTH     LENSES     GIVE     HIGH     QUALITY 

Short  focal  length  lenses  for  wide  angle  projection  are 
quite  difficult  to  design,  but  special  attention  was 
given  to  this  phase  in  computing  the  Super-Snaplites. 

DOES    THE    PICTURE    PROJECTED    BY    A    SUPER-SNAPLITE    HAVE 

THE  SAME  QUALITIES  IN  ALL  FOCAL  LENGTHS? 

Yes.  Due  to  the  unique  design  of  the  Super-Snaplite, 
the  picture  projected  by  a  2"  lens  shows  as  good  defi- 
nition, flatness  of  field  and  uniformity  of  light  as  with 
the  more  popular  sizes  such  as  4"  or  4ty2". 

ARE  THE  SIZES  OF  THE  VARIOUS  ELEMENTS  THE  SAME  FOR  ALL 
FOCAL  LENGTHS? 

No — the  elements  are  designed  for  each  focal  length 

and  vary  in  size. 

WHAT  IS  THE  TOLERANCE  IN  FOCAL  LENGTHS  OF  SNAPLITES? 

Snaplite  lenses  are  all  within  the  tolerance  of  plus  or 
minus  1%  recommended  by  the  Society  of  Motion  Pic- 
ture Engineers. 

IN    ACTUAL   PRACTICE    WHAT   DOES    THIS    PLUS    OR    MINUS    1% 

MEAN? 

It  means  that  the  actual  picture  size  for  any 
focal  length  lens  will  be  within  plus  or  minus 
1%  of  the  computed  picture  size.  Thus  if  a  20 
ft.  (240")  wide  picture  is  desired,  the  actual 
projected  picture  might  be  238"  or  242"  and 
still  fall  within  the  accepted  tolerances. 


'You  Get  the  Most  Uniform  Light  with  Super-Snaplite" 

(^tifaat   CORPORATION 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


23 


Relative  Toxicity  of  Nitrate  and  Acetate  Film  Stock 

By  DR.  E.  K.  CARVER 

Research   Laboratories,    Eastman    Kodak   Company 


RECENTLY  IP  posed  the  following 
question:  "If  acetate  film  should 
ignite,  would  it  give  off  the  same  toxic 
fumes  as  nitrate?"  The  answer  to  this 
question  is  "no". 

Acetate  film  is  about  like  paper  or 
wood  in  this  respect,  but  is  considerably 
harder  to  burn  than  either  of  them.  No 
one  likes  to  breathe  acetate  wood  smoke, 
nor  would  they  like  to  breathe  acetate 
film  smoke.  One  is  about  as  bad  as  the 
other. 

The  toxic  fumes  from  nitrate  film  are 
chiefly  nitric  oxides,  although  carbon 
monoxide  is  also  generated.  It  is  the 
nitric  fumes  which  are  insidious.  Breath- 
ing them  may  bring  on  edema  of  the 
lungs  many  hours  after  exposure.  The 
victim  may  not  know  of  this  danger  and 
so  may  not  seek  proper  medication  until 
too  late.  Acetate  film  cannot  give  off 
these  nitric  oxides. 

Vital  Difference  in  Characteristics 

However,  the  chief  danger  from  nitrate 
film  is  really  caused  by  the  large  volume 
of  fumes  that  can  be  given  off  rapidly 


even  in  the  absence  of  sufficient  air  to 
support  combustion.  If  nitrate  film  were 
no  more  combustible  nor  more  liable  to 
decomposition  than  acetate  film,  there 
would    be    little    toxicity   hazard    except 

All  Kodak  Projector  Prices  Slashed 

Kodak's  two  popular  16-mm  sound  projec- 
tors— the  Kodascope  FS-10-N  and  the  FB- 
40  projectors — have  been  reduced  in  price. 
The  FS-10-N  single-speaker  unit  has  been 
dropped  from  $500  to  $345.  The  twin- 
speaker  unit  formerly  priced  at  $565  is  now 
$395. 

The  FB-40  projector,  which  has  the  great- 
est undistorted  watt  output  now  available 
from  a  portable  tungsten  16-mm  sound-pro- 
jection equipment,  40  watts,  has  been  re- 
duced from  $855  to  $585. 

Both  of  these  projectors  are  equipped  with 
Kodak's  unique  fidelity  tone  control  which 
assures  the  finest  sound  reproduction  from 
all  types  of  16-mm.  sound  films — originals, 
duplicates,  or  reduction  prints  from  35-mm. 
And,  like  all  Kodascope  projectors,  these  two 
units  are  equipped  with  the  exclusive  field 
flattening  element  of  their  lenses  which  re- 
sults in  corner-to-corner  sharpness  on  the 
screen. 


under  very  special  circumstances.  It  is 
the  fact  that  nitrate  carries  its  own  sup- 
ply of  oxygen  that  really  makes  it  haz- 
ardous. Acetate  film  burns  very  slowly 
and  does  not  decompose  at  all  unless 
there  is  an  outside  source  of  heat. 

It  is  a  bit  difficult  to  understand  why 
this  point  has  come  up.  It  would  be 
possible,  if  some  one  were  attempting  to 
prove  that  acetate  film  were  dangerous, 
for  them  to  quote  figures  showing  that  if 
acetate  film  were  roasted  by  some  source 
of  outside  heat,  it  could  be  made  to  give 
off  toxic  fumes.  This  is  also  true  of 
wood,  paper,  wool,  rayon  and  many  other 
materials  which  we  do  not  ordinarily 
consider  hazardous. 


BOOK     REVIEW 

An  Introduction  to  Color,  by  Ralph 
M.  Evans.  340  pages,  7%  x  10,  profusely 
illustrated,  including  15  color  plates,  in- 
dexed. $6.  John  Wiley  &  Sons,  New  York; 
Chapman  &  Hall,  London,  or  at  all  Kodak 
stores. 

A  completely  descriptive  and  non-mathe- 
matical book  on  color,  intended  for  all  per- 
sons interested  in  the  subject — including 
photographers,  designers,  interior  decorators, 
artists,  engravers,  and  many  others — has  re- 


You  Sell 

A  Picture  On  a  Screen... 
Make  It  the  Best  with 


f^nJe£ 


You  invest  heavily  in  a  building,  equipment,  and  personnel  to  sell 
one  thing  ...  a  moving  picture  on  a  screen.  You  can't  afford  to  skimp 
on  that.  Your  screen  images  must  be  the  finest  .  .  .  critically  defined, 
uniformly  brilliant,  pleasant  to  look  at.  One  way  you  can  be  sure 
that  your  screen  images  are  the  finest  is  to  use  Bausch  &  Lorab  Super 
Cinephor  projection  lenses,  the  standard  of  excellence  in  the  theatre 
field.  Bausch&Lomb  Optical  Co .,  616-C  St.  Paul  St.,  Rochester  2,  N.Y. 

BAUSCH  &  LOMB 


OPTICAL  COMPANY 


ROCHESTER  2,  N.  Y. 


24 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


cently  been  put  on  the  market.  The  book, 
"An  Introduction  to  Color,"  by  Ralph  M. 
Evans,  Superintendent  of  Color  Quality  Con- 
trol at  Eastman  Kcdak  Co.,  is,  as  its  name 
implies,  truly  an  "introduction"  to  the  sub- 
ject of  color. 

Color,  according  to  the  author,  sprawls 
across  the  enormous  subjects  of  physics, 
physiology,  and  psychology.  However,  the 
book  has  been  written  on  the  assumption 
that  the.  reader  has  little  or  no  knowledge  of 
these  three  subjects,  nor  of  more  than  high 
school  mathematics.  The  text  is  set  forth 
in  consistent,  understandable  terminology 
and  is  profusely  illustrated  with  explanatory 
graphs  and  charts  and  full-page  color  plates. 

"An  Introduction  to  Color"  approaches 
the  subject  from  the  three  aforementioned 
angles  and  then  discusses  the  interrelation- 
ship of  each.  The  type  of  material  covered 
is  indicated  by  some  of  the  chapter  head- 
ings— Color  and  Light,  The  Physical  Nature 
of  Light,  The  Physics  of  Everyday  Color, 
The  Visual  Variables  of  Color,  Color  Per- 
ception, The  ^Measurement  of  Color,  Effects 
of  Illuminants,  Color  in  Photography,  Color 
in   Art,   and   Design    and   Abstraction. 

''An  Introduction  to  Color"  is  available 
through   all   Kodak  dealers  at  $6   per  copy. 


'Klenz/  New  Optics  Cleaner, 
Now  Available  Generally 

To  overcome  impaired  definition  of  pic- 
ture screen  image  and  sound  reproduction 
there  is  now  available  a  new  and  scientific- 
ally correct  means  for  removing  dust,  dirt 
or  any  other  foreign  substance  from  lenses, 
condensers  and  mirrors.  This  new  product, 
known  as  "Klenz,"  is  sponsored  by  Essannay 
Electric  Mfg.  Co.,  of  Chicago,  makers  of 
tlit  Strong  Zipper  Changeover  and  other 
projection  accessories. 

Klenz  works  quickly  and  efficiently,  with 
only  a  few  drops  being  applied  to  any  highly- 
polished  surface  and  then  wiped  off  with  a 
s,>ft  cloth.  Essannay  warrants  that  this 
■product  is  absolutely  safe  for  use  on  the 
finest  optics. 

Now  in  progres  is  a  wide-scale  promotional 
campaign  in  behalf  of  Klenz,  in  which  hun- 
dreds of  3-ounce  bottles  are  being  mailed 
to  projectionists  throughout  the  United 
Slates  on  a  money-back-if-not-satisfied  basis. 
Complete  satisfaction  is  warranted  for  Klenz, 
or  the  price  of  $1.50  will  be  refunded. 

This  trial  offer  anent  Klenz  is  available 
through  Essnnay  at  1438  North  Clark  St.. 
Chicago  10.  the  director  of  which  is  Clarence 
Jalas.  secretary-treasurer  of  IA  Local  110. 
Klenz  will  soon  be  available  through  all  mo- 
tion  picture  supply   dealers. 


'Pulse'  System  for  Theatre-Tv 
Network  Cited  at  IRE  Meet 

Use  of  city-wide  Tv  networks  to  carry 
spot  news,  special  current  events  and  other 
happenings  from  central  depots  to  motion- 
picture  theatres  over  special  high-frequency 
radio  channels  set  up  for  the  purpose,  was 
foreseen  at  the  recent  convention  of  the 
Institute  of  Radio  Engineers  (N.  Y.  City) 
us  a  "certainty  within  five  years." 

Such  systems,  operating  on  radar-like  prin- 
ciples  developed   in   the  late   war,   not  only 


might  be  city-wide  in  scope  but  eventually 
might  be  used  on  a  national  or  even  inter- 
national basis. 

Emil  Labin,  engineer-director  in  charge  of 
microwave  operations  at  the  Federal  Tele- 
communications Laboratories  (Nutley,  N.  J.) 
expounded  this  view  of  the  future  in  radio 
communications  after  a  convention  session 
on  new  "modulation   systems." 

"  'Pulse'  modulation  systems,"  he  said, 
"incur  no  distortion,  no  matter  how  exten- 
sive they  may  be,"  but  could  be  carried  on 
nationally  or  even  internationally.  Pulse 
modulation,  he  added,  is  the  newest  thing 
in  radio  modulation  and  is  accomplished  by 
"sampling"  a  program  at  a  rate  of  millions 
of  times  a  second  and  then  transmitting  the 


samples  for  a  radio  receiver  to  unravel. 
He  explained  further  that  pulse  modula- 
tion was  not  a  new  idea,  but  had  been  under 
development  for  years.  Now,  however,  "it  is 
just  beginning  to  be  appreciated."  A  single 
pulse  station,  he  said,  could  carry  as  many 
as  a  dozen  programs  at  the  same  time  over 
a  single  radio  spectrum  assignment  to  re- 
ceivers, which  could  be  attuned  in  the  home 
io  any  one  of  the  programs. 


Carbon  Arc  Picture  Going  Abroad 

National  Carbon  Co.  announces  that  its 
Technicolor  motion  picture,  "Carbon  Arc 
Projection,"  has  been  selected  by  the  Office 
of  International   Information,   Department  of 


Operating  at  85  amperes,  the  Motiograph-Hall  produces  19,000  lumens — more  light 
than  condenser-type  high  intensity  lamps  operating  at  more  than  twice  this  am- 
perage. 

A  rotating  positive  carbon  (an  exclusive  feature)  permits  even  burning  of  the 
carbons  and  a  proper  crater  form. 

Due  to  the  extremely  high  intrinsic  brilliancy  of  the  Motiograph-Hall  arc,  the 
total  light  output  contains  a  much  larger  percentage  of  visible  light,  making  unnec- 
essary the  use  of  a  filter  which  would  reduce  the  amount  of  visible  light  passed. 

The  automatic  focus  control,  another  exclusive  feature,  constantly  holds  the 
crater  of  the  positive  carbon  at  the  exact  focal  point  of  the  mirror,  preventing 
variations  in  the  character  of  the  light  at  the  screen. 

The  Motiograph-Hall  lamp  is  designed  to  use  9-mm.  or  11 -mm.  high  intensity 
positive  carbons  and  5/16"  negative  carbons,  the  cost  of  which  is  about  one-third 
that  of  the  cost  of  the  larger  carbons  used  in  condenser-type  lamps  operating  in 
the  140-180  ampere  range. 

Other  Motiograph  products  include  Motiograph  1  K.W.  and 
46-ampere  high  intensity  arc  lamps,  Motiograph  projectors, 
indoor  and  outdoor  sound  systems,  generators  and  rectifiers, 
in-car  speaker  equipment  and  junction  boxes,  ramp  switching 
panels  for  drive-ins,  turntables,  etc. 

Literature  and  Complete   Information   May  be  Obtained  from 


monoGRAPH,  inc., 


4431     W.     LAKE     ST.,     CHICAGO     24,     ILL. 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


25 


State,  for  distribution  throughout  52  foreign 
countries  and  their  dependencies.  Films  so 
distributed  comprise  documentary  and  in- 
formational subjects  covering  many  aspects 
of  American  life  to  be  shown  in  non-com- 
mercial theatres,  without  admission  charge, 
to  foreign  audiences  totaling  over  100  mil- 
lion persons  a  year. 

"Carbon  Arc  Projection"  demonstrates 
the  optics  of  motion  picture  projection,  what 
the  carbon  arc  is  and  how  it  operates,  and 
explains  why  this  light  source  has  the  bril- 
liancy and  color  balance  ideally  suited  for 
motion    picture    production    and    projection. 

The  picture  is  educational  and  entertain- 
ing not  only  for  motion  picture  technicians 
but  also  for  schools,  universities,  etc. 


IN  THE  SPOTLIGHT 

(Continued  from  page  19) 

electrical  branch  of  the  Navy  during 
World  War  I,  and  upon  his  discharge  he 
became  associated  with  the  Paramount 
Studios  in  Hollywood,  where  he  has  re- 
mained ever  since. 

•  Eddie  Miller,  IA  representative  and 
business  agent  for  Houston  Local  279, 
successfully  concluded  negotiations  for 
the  Texas  Locals  (District  No.  6) ,  ob- 
taining for  each  Local  a  flat  15%  wage 
increase,  retroactive  to  September  1 
last;    two-week  vacations  with  pay;    ad- 


THE  CTDANfi  TDOI«IMB1 
nE  91  KUNli  I  KUUrBI 


A.  C.  CARBON  ARC  SPOTLIGHT 


for  theatres,  auditoriums  and  night  clubs  where  the 
length  of  throw  does  not  exceed  100  feet. 


PRODUCING  A  SNOW  WHITE  uniformly  illum- 
inated spot,  crisp  on  the  edges,  the  Trouper 
will  supply  that  essential  sparkle  to  a  pres- 
entation that  is  obtainable  only  with  the  use 
of  high   intensity  arcs. 

FAR  SURPASSING  IN  BRILLIANCY  of  spot  any 
incandescent  or  vertical  arc  type  spotlight, 
the  Trouper  will  actually  equal  many  of  the 
large  theatre  type  spotlights. 
ENGINEERED  WITH  AN  EYE  toward  simplicity 
and  ease  of  operation,  this  spotlight  is  capable 
of  being  easily  operated  by  a  "new"  man  on 
"opening   night". 

THE  OPTICAL  SYSTEM  utilizes  a  silvered 
glass  reflector  to  collect  the  illumination  from 
the  source  and  direct  it  to  a  circular  aperture, 
from  where  it  is  projected  to  the  stage  by 
means  of  a  two  element  variable  focal  length 
lens  system. 

FOR  A  60-FOOT  LENGTH  OF  THROW,  the  size 
of  the  projected  spot  is  variable  from  a  mini- 
mum of  30  inches  "head  spot"  to  a  maximum 
of  33  feet  "flood". 

EXTREMELY  MODEST  IN  ITS  POWER  require- 
ments,   this   spotlight   draws   only    10   amperes 


from  any  alternating  current  110-volt  con- 
venience outlet. 

A  HIGHLY  EFFICIENT,  adjustable  and  self- 
regulating  transformer  which  is  an  integral 
part  of  the  spotlight  base  reduces  the  110- 
volt  alternating  current  supply  to  a  low  arc 
voltage  and  for  the  first  time  makes  possible 
a  high  intensity  arc  spotlight  without  the  use 
of  heavy  rotating  equipment. 
THE  CARBONS  ARE  FED  AUTOMATICALLY 
by  an  electric  motor  which  maintains  a  con- 
stant arc  gap.  This  results  in  a  steady  light, 
free  from  hiss  or  flicker. 

A  TRIM  OF  CARBON  consists  of  two  6mm  x 
7"  heavy  copper  coated  high  intensity  carbons 
with  a  burning  time  of  one  hour  and  twenty 
minutes  at  21  volts  and  45  amperes  arc  cur- 
rent. 

A   HORIZONTAL  MASKING  CONTROL  can   be 

angled   at  45   degrees   in   each   direction   from 

horizontal. 

THE   COLOR   BOOMERANG   contains   six  slides 

and  an   ultraviolet  filter  holder. 

MOUNTED  on  casters.  Easily  disassembled  into 

two  units  for  shipment. 


SOLD  BY  INDEPENDENT  THEATRE  SUPPLY  DEALERS. 
Use  the  coupon  to  obtain  further  details,  prices  and  name  of  your  nearest  dealer. 


THE 

STRONG 

ELECTRIC  CORP. 

"The  World's  Largest  Manu- 
facturer of  Projection 
Arc  L 


14  CITY  PARK  AVE. 
TOLEDO   2,   OHIO 


Please  send  free  literature,  prices  and  name  of  the 
nearest  dealer  in  Strong  Spotlights. 


NAME      

COMPANY     

STREET    

CITY  and   STATE 


Thomas  Smale 


justments  on  overtime  rates,  and  increases 
for  midnight  shows. 

•  Bill  Keeler,  newly-elected  business 
agent  for  San  Antonio  Local  407,  brings 
to  his  office  a  wealth  of  experience. 
Business  agent  of  the  Local  about  20 
years  ago,  Bill  has  at  his  finger  tips  all 
the  whys  and  wherefores  so  essential  to 
an  efficient  and  able  union  official. 

•  Thomas  Smale,  member  of  Detroit 
Local  199  and  projectionist  for  the  past 

10  years  at  the 
Van  Dyke  Thea- 
tre, is  another 
I A  man  who  has 
risen  high  in  the 
order  of  Mason- 
ry. He  was  raised 
in  Daylight 
Lodge  No.  525, 
F.  &  A.  M.,  back 
in  1929,  and 
since  then  has 
been  accorded 
many  Masonic 
honors.  In  1945 
the  Michigan  Council  of  Deliberation, 
the  governing  Body  of  the  Rite  in  the 
State,  conferred  upon  him  the  Meritorius 
Service  Award  in  recognition  of  his  many 
contributions  to  the  Rite.  In  September 
1948,  at  Boston,  he  was  elected  to  re- 
ceive the  33rd  degree  and  to  Honorary 
Membership  in  the  Supreme  Council, 
both  of  which  will  be  conferred  upon 
him  at  Chicago  next  September. 

Smale  began  his  projectionist  career 
in  1912  at  Windsor,  Ont.,  Canada.  After 
serving  with  the  Canadian  Army  in 
World  War  I,  he  returned  to  Windsor 
and  organized  Local  580,  becoming  its 
first  business  agent.  He  served  three 
years  as  business  agent  of  the  Local  and 
one  year  as  president.  Later  he  moved 
to  Detroit  where  in  1929  he  joined 
Local  199. 

'Arctic  Blanch'  Screen  Refinishing 

Sole  ownership  and  direction  of  Na- 
tional Theatre  Screen  Refinishing  Co.,  of 
Buffalo,  is  now  vested  in  Ken  Caldwell, 
one  of  the  original  partners  in  the  "Arc- 
tic Blanch"  screen  reconditioning  pro- 
cess. Caldwell,  a  member  of  Buffalo 
Local  233,  emphasizes  the  fact  that  this 
process  is  not  even  remotely  intended  to 
delay  the  purchase  of  a  new  screen  but 
rather  to  improve  materially  projection 
when  the  purchase  of  a  new  screen  is  not 
feasible. 

That  the  Arctic  Blanch  reconditioning 
process  makes  a  "whale  of  a  difference" 
in  the  image  projected  to  any  screen  that 
has  been  in  use  for  some  time,  Ken  offers 
to  prove  by  means  of  a  pamphlet  con- 
taining testimonials  from  scores  of  satis- 
fied users  in  theatres  of  all  classifications. 
Address  129  Zenner  St.,  Buffalo  11,  N.  Y. 


26 


INTERNATIONAL  PROJECTIONIST 


March  1949 


New  Film  Cabinet  Features  a 
Built-in  'Waterfall' 

The  seething  1500-degree  heat  of  flames 
from  kerosene-soaked  pine  kindlings  failed 
to  damage  24,000  feet  of  nitrate  film  in  a 
new  motion  picture  film  storage  cabinet 
which  was  tested  recently  in  the  open  air 
at  Washington,  D.  C,  it  was  announced 
by  John  G.  Bradley,  who  developed  the 
cabinet.  Although  the  blazing  kindling  sur- 
rounded the  cabinet,  exposing  all  sides  of 
it  to  the  intense  heat,  the  temperature  in- 
side the  cabinet  was  not  raised  above  ap- 
proximately 70  degrees.  Cans  of  film  re- 
moved from  the  cabinet  immediately  after 
the  test  were  handled  by  observers  and 
described   as  "cool   as  a  cucumber." 

In  a  second  test,  one  of  the  24  cans  of 
film  was  ignited  by  means  of  a  heat  coil, 
charged  electrically  through  an  external 
wire  connection  after  the  cabinet  was  closed, 
and  while  the  1000  feet  of  film  in  the  single 
can  was  completely  destroyed,  film  in  the 
remaining  23  cans  was  unaffected. 

Each  Film  Can  Doused  With  Water 

The  principle  which  makes  the  cabinet 
fireproof  and  virtually  heatproof  is  a  built- 
in  "waterfall"  which  immediately  covers  each 
can  of  film  with  flowing  water  in  event  of 
fire  either  inside  or  outside  the  cabinet. 
Known  as  a  "water-seal  cascade"  type  of 
film  storage  cabinet,  it  is  expected  to  find 
application  in  theatre  projection  rooms,  film 
libraries,  production  studios,  etc. 

The  cabinet,  patented  for  Mr.  Bradley  by 
the  Federal  government,  with  the  latter  re- 
taining right  of  use,  is  constructed  to  hold 
the  cans  of  film  horizontally,  to  avoid  seep- 
age of  water  into  the  cans  when  the  sprink- 
ler system  is  in  operation.  The  present  de- 
sign, and  probably  average  commercial  size, 
is  for  24  cans,  each  holding  1000  feet  of  film. 


Slant  Lines  Held  Less  Visible 

Two  Kodak  scientists  studying  the  sharp- 
ness of  vision  have  come  up  with  an  experi- 
ment you  yourself  can  try  with  your  daily 
newspaper.  The  two  researchers,  George  C. 
Higgins  and  Keith  Stultz,  found  that  the 
visibility  of  parallel  lines  in  a  test  object 
used  in  their  experiments  is  10  to  20% 
lower  when  the  lines  were  viewed  at  an  angle 
of  45  degrees  to  the  horizontal.  The  lines 
are  that  much  more  difficult  to  see  when 
turned  at  that  angle. 

You  can  easily  see  this  effect  when  you 
look  at  a  newspaper  halftone  picture,  which 
is  made  up  of  rows  of  tiny  dots  and  serves 
very  well  as  a  test  object.  Turn  the  news- 
paper picture  halfway  to  the  right  or  left 
so  that  the  lines  of  dots  are  either  vertical 
or  horizontal.  The  result,  if  you  have  the 
picture  at  average  reading  distance  and  if 
it  is  of  moderate  density,  is  that  you  will 
see  the  lines  stand  out  in  the  picture. 

Marked  Change  Visible  at  45°  Angle 

By  turning  the  picture  back  to  normal 
position,  so  that  the  lines  of  dots  are  at  an 
angle  of  45  degrees  to  the  horizontal,  the 
systematic  array  of  dots  disappears.  There 
is  marked  increase  in  the  clarity  of  the 
picture.  This  is  one  of  the  reasons  that 
newspaper  halftones  are  usually  made  with 


the  two  sets  of  parallel  lines  passing  diag- 
onally rather  than  vertically  before  your  eyes. 
This  is  believed  to  be  the  first  time,  how- 
ever, that  scientific  data  has  been  reported 
on  the  variations  of  visual  sharpness  meas- 
ured with  test  objects  consisting  of  parallel 
lines  passing  at  different  angles  before  the 
eyes  of  the  observer.  The  work  at  Kodak 
Laboratories  is  part  of  a  general  study  of 
vision  and  its  relation  to  better  pictures. 

T-NUMBER   vs.    F-NUMBER   MARKS 

(Continued  from  page  17) 

the  F-number  of  an  ideal  lens,  of  circular 
aperture  and  100%  light  transmission, 
which  would  give  the  same  axial  image 
illumination  as  the  actual  lens  at  the 
specified  stop  opening. 

In  short,  the  old  .F-number  gave  the 
purely  dimensional  ratio  of  focal  length 
to  diameter  of  a  lens,  but  ignored  varia- 
tions in  transmission  of  light;  whereas 
the  T-number  defines  the  same  ratio 
modified  in  accordance  with  the  light 
transmission  of  the  lens,  and  thus  renders 


PETER  M.  WELLMAN— Owner, 
P.  M.  Wellman  Theatres  (10  theatres, 
4  drive-ins),  Girard,  Ohio — says: 
"Sound  equipment  in  my  thea- 
tres is  of  No.  1  importance  to  me. 
I've  found  what  I  want  in  RCA 
equipment  and  RCA  Service." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


Manufactured  by 

HEYER-SHULTZ,  Inc. 


MONTCLAIR,  N.  J. 


ALL   METAL 

GUARANTEED  5  YEARS 


Distributed  Exclusively  by 


MJURRD  UUilMER 

Flutter  Suppressor  Wins 
ACADEMY   AWARD! 


The  Academy  of  Motion  Picture  Arts  &  Sciences  recog- 
nized the  value  of  this  development  in  making  its  1947 
award  to  C.  C.  Davis  of  the  Western  Electric  Co. 

CENTURY  can  give  you  this  outstanding  improvement 
in  sound  reproduction   NOW. 


The  Award- 
winning  Hydro 
Flutter  Suppressor 
as  used  in  the 
new  Century 
sound  reproducer. 


Improve   the    perform- 
once    quality   in    your    theatre  —  see 
'  your  dealer  or  write  for  information. 

CENTURY  PROJECTOR  CORP 

New  York,  N.  Y. 


Century  Sound  Reproducer 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


27 


possible  exact  comparison  between  rapid- 
ity  (speed)   of  lenses. 

Well,  one  will  say,  that  is  all  to  the 
good:  we  want  the  greatest  possible  ac- 
curacy in  all  our  instruments  of  pre- 
cision. ...  It  is  not  quite  as  simple  as 
that,  for  the  tendency  of  the  moment — 
having  its  origin,  it  should  be  pointed 
out,  with  the  motion  picture  industry  of 
the  U.  S.  A. — is  to  use  the  F-scale  not  as 
an  adjunct  to  the  F-number  but  to  re- 
place it. 

Serious  Inconvenience  Cited 

Now,  such  a  procedure  may  cause  quite 
a  little  inconvenience  to  serious  workers 
in  several  photographic  spheres,  and 
before   any   final   decision    is   arrived    at, 


and  certainly  before  any  decision  is  made 
binding  upon  all  lens  manufacturers,  we 
should  like  to  suggest  that  very  careful 
consideration  be  given  to  the  matter.  We 
have  in  mind  especially  the  question  of 
lenses  for  process  work  and  for  color 
photography,  the  latter  particularly  in 
relation  to  record  work  of  a  scientific 
nature. 

It  must  not  be  forgotten  that  the  coat- 
ing of  lenses  does  affect  the  spectral 
reflectivity  of  the  lens  faces,  and  that  in 
the  case  of  the  commonest  treatment 
given  in  this  country — i.e.,  a  coating  of 
magnesium  fluoride — the  lens  finishes  up 
with  an  appreciably  greater  transmission 
in  the  centre  of  the  visible  spectrum — 
that    is,    in    the    yellow-green — than    at 


Meet  your  demand  for 

HIGH  INTENSITY  PROJECTION  and 
UNIFORM  SCREEN  ILLUMINATION 

with 
HERTNER  Type  CPf 


Drive-in  and  deluxe  theatres,  large  auditoriums  and 
halls  must  have  plenty  of  light  on  the  screen  with 
uniform  illumination.  That's  why  the  Hertner  CP 
Transverter  is  so  popular  with  such  operators.  This 
Transverter  gives  you  these  advantages: 

1.  Range  of  capacities  3.  High  intensity 

2.  Close  voltage  regulation       4.  Uniform  screen  illumination 

Demand  equipment  that  gives  you  these  advantages. 
Specify  the  CP  Transverter.  For  complete  information 
consult  your  nearest  National  Theatre  Supply  dealer. 


either  the  violet-blue  or  the  red  end  of 
the    spectrum. 

That  there  may  be  as  much  as  2%  less 
transmission  at  4000  A  than  at  5600  A 
per  single  lens  surface  is  surely  a  warn- 
ing that  there  are  many  facets  of  this 
matter  that  require  the  most  careful  con- 
sideration, and  that  we  certainly  want 
very  much  more  experimental  study  and 
accumulated  data  before  any  final  de- 
cisions are  arrived  at. 

Other  Important  Aspects 

Another  most  important  aspect  that 
must  not  be  overlooked  is  the  fact  that 
the  T-number  seeks  to  standardize  the 
rapidity  (speed)  of  a  lens  to  the  exclu- 
sion of  other,  and  more  fundamental, 
constants.  In  particular,  in  a  world  of 
lenses  from  which  the  F-number  has  been 
banished,  all  our  depth-of-field  tables  and 
calculations  will  cease  to  have  any  pre- 
cise meaning:  they  will  become  inaccu- 
rate by  precisely  the  degree  by  which 
our  rapidity  measurements  will  have 
gained  in  accuracy ;  and  it  must  be  borne 
in  mind  that  a  25%  error  in  depth  of 
focus  is  quite  an  important  thing  to  the 
technical  worker. 

On  the  other  hand,  it  is  a  fact  that— 
outside  color  photography  and  certain 
scientific  work — it  is  impossible  to  detect 
an  error  of  exposure  of  much  less  than 
25%,  so  that  the  vast  majority  of  photog- 
raphers would  never  know,  so  far  as 
their  exposures  were  concerned,  that 
their  F-numbers  had  become  F-numbers 
if  they  had  not  been  so  marked. 

Furthermore,  every  time  a  lens  was 
cleaned — tenderly  wiped  though  it  might 
be  with  lens  tissue — its  F-number  would 
be  altered;  whereas  even  the  forceful 
wielding  of  a  saucepan-scraper  would  not 
avail  to  change  the  F-number,  which  is 
based  upon   unalterable   constants. 

And,  incidentally,  is  it  reasonable  to 
suppose — having  regard  to  the  inherent 
delicacy  and  relative  uncertainty  of  lens 
coating — that  lens  manufacturers  will 
wish  to  be  saddled  with  the  additional 
unwelcome  burden  of  guaranteeing,  by 
engraving  F-numbers  within  a  fairly 
close  tolerance,  the  efficacy  of  their  coat- 
ing for  an  unspecified  range  of  wave- 
lengths, together,  presumably,  with  the 
obligation  to  supply  a  statement  as  to 
the  variation  of  the  F-faclor  according 
as  non-color-sensitive  or  hyperpanchro- 
matic  material  is  used  with  it? 

Favors  Retaining  F-Number 

Surely  the  obvious  course  is  to  stick 
to  F-numbers  and  to  supply  with  each 
lens,  if  desired,  a  calibration  chart  giving 
the  F-factors  for  a  range  of  wave-lengths 
by  which  all  exposure  must  be  corrected. 
This  will  satisfy  the  specialist — who  will 
thereby  be  better  served  than  the  en- 
graved F-numbers,  since  he  will  have  the 


28 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


advantage  that  he  really  will  know  what 
he  is  doing — without  sacrificing  any 
fundamental  principles  or  disturbing  the 
equanimity  of  the  ordinary  user,  who, 
frankly,  doesn't  want  to  be  bothered  with 
hair-splitting  refinements. 

The  desire  for  greater  accuracy  is 
laudable,  but  the  value  of  that  greater 
accuracy  will  be  greatest  in  scientific 
work  and  in  the  process  studios,  and  it 
is  just  in  those  spheres  that  the  selective 
reflectivity  we  have  mentioned  will  play 
the  largest  part,  and  possibly  prove  to 
be  of  the  greatest  inconvenience. 

Let  us  use  every  means  of  progress 
possible,  but  before  making  decisions 
let  us  be  sure  that  we  have  explored 
all  the  possibilities  and  weighed  all  the 
advantages  and  drawbacks,  both  to  every 
class  of  user  and  to  the  manufacturers. 

[Note:  Comment  on  the  foregoing  evalua- 
tion of  ^-numbers  and  F-numbers  is  solicited 
by  IP,  particularly  from  manufacturers  of 
optical  products. — Ed.1 


BUILDING 


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THEATRE   TV    PRESENT   STATUS 

(Continued  from  page  12) 

only  80  watts.  With  a  screen  efficiency 
of  5  candlepower  per  watt  this  repre- 
sents a  light  output  of  400  candlepower. 

Optical  System  Efficiency 

The  familiar  refractive  projection 
optics  used  in  motion  picture  film  pro- 
jectors deliver  approximately  6%  of  the 
light  from  the  arc-light  source  to  the 
screen.  On  the  other  hand,  the  reflec- 
tive optics  developed  for  Tv  vision  de- 
liver 30%  of  the  light  output  from  the 
cathode-ray  tube  to  the  screen. 

Reflective  optics  have  been  designed 
for  large-screen  projection  of  pictures 
up  to  18  x  24  feet.  One  system  for  a 
iy-2.  x  10-foot  screen  uses  a  21-inch 
mirror,  a  14-inch  "lens"  (correction 
platet),  and  a  7-inch,  50-kilovolt,  cath- 
ode-ray tube.  The  largest  system  built 
so  far  consisted  of  a  42-inch  mirror,  a 
26-inch  "lens,"  and  12-  and  15-inch  pro- 
jection tubes  operating  at  80  kilovolts. 
The  throw  was  fixed  at  40  feet,  and  by 
changing  the  cathode-ray  tube  either  a 
15-  x  20-  or  an  18-  x  24-foot  picture  was 
shown. 

The  magnification  is  fixed  by  the  mir- 
ror radius.  High  present  production 
cost  of  large-mirror  systems  seemingly 
indicate  the  advisability  of  concentrat- 
ing on  smaller  optics  and  increasing  the 
voltage  capabilities  of  smaller  cathode- 
ray  tubes  (7-inch)  in  order  to  make  a 
compromise  system  which  might  be  suc- 
cessful commercially. 

The  viewing  screen  forms  the  third 
and  final  optical  element  of  direct-pro- 
jection Tv.  Standard  motion  picture 
screens  have  a  diffuse  surface  which  dis- 
tributes the  light  more  or  less  uniformly 
in  all  directions.  Since  the  distribution 
is  nondirectional.  a  great  deal  of  light 
is  lost  to  the  ceiling  and  floor.  Directivity, 
if  it  could  be  obtained  in  the  vertical 
plane,  would  concentrate  the  light  where 
it  would  be  most  useful  and  effect  an 
important  increase  in  efficiency. 

Lenticular  Screen  Test  Successful 

Beaded  screens  have  been  made  to 
control  the  direction  of  the  reflected 
light  from  the  screen,  but  the  directivity 
pattern,  while  showing  a  gain  of  2,  re- 
stricts the  horizontal  reflective  pattern 
and  tends  to  reflect  a  great  deal  of  illum- 
ination back  into  the  optical  system 
where  it  reduces  the  contrast  of  the  pro- 
jected image.  Developments  in  direc- 
tional screens  now  underway  promise 
gains  as  high  as  3. 

A  lenticular  screen  of  this  type  was 
successfully  used  in  the  Fox  Theatre  in 
Philadelphia  where  a  15-  x  20-foot  pic- 


i  See    "Basis    of    the    Schmidt    Optical    System,"    IP 
for    September,    1948,   p.   8. 


ture  was  shown  featuring  the  1948  Louis- 
Walcott  fight.  This  screen  is  embossed 
on  an  aluminized  surface,  with  small 
convex-lens  elements  to  control  the  di- 
rectivity  pattern.     The   observed  results 


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U.L.  approved.  Eliminates  fire 
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safety  cut-off  .  .  .  when  door  opens 
or  film  breaks,   motor  s/ofts. 

Available  thru  Leading 
Theatre  Supply  Dealers 

Send  for  Bulletin  No.  456 


GoldE  Manufacturing  Co., 

1222-P  W.  MADISON  ST.,  CHICAGO  7,  ILL 


BOLIVAR  HYDE— General  Man- 
ager, Talgar  Theatre  Co.,  Lakeland, 
Florida — declares : 
"We  have  used  RCA  Service  for 
over  14  years,  and  have  found  this 
service  satisfactory  and  economi- 
cal. Our  equipment  always  is  kept 
in  excellent  condition." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


INTERNATIONAL  PROJECTIONIST 


March  1949 


29 


were  excellent,  and  a  gain  of  2V£  times 
was  measured. 

Such  is  not  the  case  with  a  normal 
translucent  screen  (rear  projection), 
since  the  light  comes  from  a  relatively 
small  source  and  is  a  diverging  cone  of 
light  at  the  screen.  (The  usual  trans- 
lucent screen  receives  direct  rays  which 
are  normal  to  the  center  of  the  screen 


A 


but  diverge  nearer  the  edges,  resulting 
in  a  bright  spot  in  the  center  of  the 
screen.) 

A  field  lens  can  be  used  on  the  rear 
of  the  transulcent  screen  to  direct  the 
rays  in  a  parallel  pattern,  and  hence  give 
more  uniform  illumination  over  the  en- 
tire screen,  or  by  a  modification  the  pat- 
tern may  be  made  to  suit  almost  any 
application.  Such  a  field  lens  may  be 
applied  only  in  small  screens  as  in  the 
home  type  of  projection  receiver  where 
a  molded-plastic  screen  can  be  used.  A 
compromise  screen  of  high-density  trans- 
lucent material  can  be  made,  but  the 
gain  will  be  low  and  the  directivity  pat- 
tern becomes  very  sharp. 

Equipment  Elements,  Location 

The  current  design  trend  for  direct- 
projection  systems  is  to  break  the  equip- 
ment into  several  discrete  units:  1.  The 
optical  housing  containing  the  mirror, 
lens,  cathode-ray  tube  and  its  associated 
deflection  coil,  and  a  cooling  system  for 
the  cathode-ray  tube;  2.  The  control  con- 
sole containing  the  critical  Tv  elements 
such  as  the  video  amplifier  and  deflec- 
tion circuits  as  well  as  the  operating  con- 
trol panel;  3.  The  auxiliary  power  equip- 
ment consisting  of  a  power-supply  rack 
and  a  high-voltage  power  unit. 

Various  locations  have  been  suggested 
and  tried  for  this  type  of  projection-Tv 
equipment.  The  present  throw  limita- 
tion makes  the  normal  booth  installation 
impracticable.  Longer  throw  systems  up 
to  65  feet  can  be  made,  but  again  the 
cost  and  size  factor  rule  them  out.  Rear 
projection  might  seem  ideal  for  short- 
throw  systems,  but  the  screen  directivity 
is  too  sharp  to  make  this  practicable. 

If  it  were  economical  to  waste  a  great 
deal  of  light  on  a  very  dense  screen, 
there  might  be  some  compromise  pos- 
sible in  this  direction.  Another  impor- 
tant consideration  in  selecting  the  loca- 
tion is  the  projection  angle,  because  the 
limited  depth  of  focus  of  the  short  opti- 
cal system  demands  operation  with  the 
screen  normal  to  the  projection  axis. 

The     installation     requirements      are 


CLAYTON  BALL-BEARING 

EVEN  TENSION  TAKE-UPS 

For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reels. 
Silent   Chain   Drives 

THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reels. 

CLAYTON    PRODUCTS    CO. 


31-45  Tibbett  Avenue 


New  York  63,  N.  Y. 


peculiar  to  the  optical  system  employed 
and  ideally  would  locate  the  optical  hous- 
ing on  the  front  of  the  balcony.  Alterna- 
tively, in  a  nonbalcony  house  the  optical 
housing  may  be  located  either  on  a  spe- 
cial ceiling  suspension  or  in  the  orches- 
tra. The  control  console  should  not  be 
more  than  15  feet  from  the  optical  hous- 
ing because  of  circuit  requirements, 
which  usually  dictate  its  placement  at 
the  balcony  rail. 

The  balance  of  the  equipment  can  be 
remotely  placed  at  any  convenient  point, 
but  cost  will  probably  indicate  a  location 
less  than  100  feet  from  the  optical  hous- 
ing. 

Picture  Quality  vs.  Resolution 

Picture  quality  from  large-screen  Tv 
projectors  is  now  limited  by  the  quality  of 
the  transmitted  signals.  The  capabilities 
of  the  projection  system  are  equal  to  the 
best  studio  equipment  and  any  deteriora- 
tion of  the  signal  between  the  camera 
and  the  projector  causes  an  inferior  pic- 
ture on  the  screen.  Experience  has 
shown  that  with  a  picture  of  suitable 
quality  it  is  possible  to  produce  results 
acceptable  to  critical  audiences. 

Present  transmission  of  Tv  pictures  on 
standard  channels  is  limited  in  band- 
width so  that  the  projected  pictures  actu- 
ally have  about  300  lines  resolution.  If 
the  pictures  were  transmitted  by  micro- 
wave relay,  the  entire  capability  of  the 
projection  system  of  approximately  350 
to  450  lines  could  be  utilized. 

A  Tv  system  specifically  designed  for 
theatre  use  will  no  doubt  be  a  private 
system  using  ultra-high-frequency  chan- 
nels, and  all  of  the  equipment  and  tech- 
niques of  operation  will  be  improved  to 


ABE  SOLOMON— President,  Inde- 
pendent Theatres,  Inc.  (operators 
of  15  theatres),  Chattanooga,  Ten- 
nessee— says: 

"RCA  Service  is  superb  and 

the  cooperation  and  ability 

of  RCA  Service  engineers  is 

unmatchable . ' ' 

To  get  the  benefits  of  RCA  Service 

—write:  RCA  SERVICE  COMPANY, 

INC.,  Radio  Corporation  of  America, 

Camden,  New  Jersey. 


30 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


utilize  the  present  standards  to  the  full- 
est extent. 
Storage-Projection  Methods 

Two  basic  image-storage  Tv  projection 
systems  are  being  investigated.  The  first 
uses  motion  picture  film  as  the  inter- 
mediate storage  medium,  while  the  sec- 
ond employs  electronic  means. 

The  film-storage  method  of  large- 
screen  Tv  projection  is  the  only  storage 
system  available  even  on  an  experimental 
basis  in  this  country.  The  system  de- 
scribed here  was  developed  by  Para- 
mount and  has  been  used  on  several  occa- 
sions in  the  Paramount  Theatre,  New 
York  City.  The  fundamentals  are  simi- 
lar in  many  respects  to  equipments  de- 
signed and  built  by  others  and  may  give 
the  motion  prcture  industry  an  insight 
into  the  problem  involved  in  setting  up 
such  a  system. 

The  film-storage  system  consists  of 
four  basic  elements:  1.  Tv  receiving 
equipment;  2.  recording  camera;  3. 
rapid  film-processing  equipment;  4.  a 
conventional  35-mm  motion  picture  pro- 
jector. In  practice,  Paramount  has  used 
mobile  cameras  together  with  microwave 
radio-relay  equipment  to  bring  the  pro- 
gram material  to  the  theatre. 

The  mobile  cameras  with  associated 
control  equipment  and  microwave-relay 
unit  are  of  the  conventional  type  used 
by  Tv  broadcasters  for  remote  pickup 
and  cost  approximately  $55,000. 

All  receiving  equipment*  is  housed  in 
one  unit.  This  includes  all  video  and 
audio  equipment  together  with  high-  and 
low-voltage  supplies.  Two  screens  are 
provided.  One  employs  a  15-inch  cath- 
ode-ray tube  for  monitoring;  the  other 
is  a  10-inch  cathode-ray  tube  having  an 
aluminum-backed,  flat-face  screen.  This 
10-inch  cathode-ray  tube  is  of  the  blue, 
short-persistence  type  and  provides  the 
received  image  which  is  photographed. 
This  screen  has  the  polarity  reversed  and 
the  received  image  is  a  negative.  Audio 
portions  of  the  program  are  monitored 
by  a  loudspeaker  included  in  this  unit. 

Camera,  Processing,  Power 

A  special  recording  camera  is  em- 
ployed having  no  mechanical  shutter  but 
having  its  pull-down  mechanism  syn- 
chronized at  the  standard  film  rate  of 
24  frames  per  second  with  an  electronic 
shutter  incorporated  in  the  circuits  of 
the  10-inch  cathode-ray  tube.  Twenty 
frames  following  exposure  of  the  pic- 
ture the  film  passes  through  the  sound 
modulator.  A  film  magazine  mounted 
directly  above  the  recording  camera 
holds  sufficient  unexposed  film  for  two 
hours  continuous  recording. 
1  Exposed  film  from  the  recording  cam- 
era passes  through  a  chute  directly  to  a 
high-speed  processing  unit.  A  maxi- 
mum of  66   seconds  is   required  to   de- 


velop, fix,  wash,  and  dry  the  exposed 
film.  Facilities  are  provided  either  to 
wind  the  processed  film  on  reels  or  feed 
it  directly  to  the   projectors.* 

The  processing  unit  requires  a  hot-  and 
cold-water  supply  of  approximately  20 
gallons  per  minute.  The  hot-water  sup- 
ply must  have  a  minimum  temperature 
of   140  °F.      Cold-water   supply   at   con- 


*  The  total  cost  of  these  three  units  (receiver, 
camera,  and  processing  unit)  is  approximately  $35,000 
plus   installation. 


ventional  tap  temperature  is  adequate. 
Automatic  mixing  is  provided  within 
the  unit  to  attain  a  resultant  tempera- 
ture of  approximately  125°F.  A  slop- 
sink  should  be  provided  for  disposal  of 
spent  photographic  chemicals. 

The  total  power  required  to  operate 
the  three  units  (receiver,  camera,  and 
processing)  is  100  amperes,  3-phase,  208 
volts  a-c. 

The  space  required  to  house  the  re- 


Niie  and  Day 

forbears 


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THE  PROJECTIONIST 

No    matter   what    you    need 
in    the    way   of    equipment  and 
supplies  ...  no  matter  what 
the    hour   of    an    emergency 
.    .    .    National    stands  ready 
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WITH   ANY     LAMP      IN  ANY  SIZE     THEATRE 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


31 


ceiving,  recording,  and  processing  units 
is  200  square  feet.  To  facilitate  opera- 
tion and  maintenance,  a  room  10  x  20 
feet  is  recommended  with  the  equipment 
set  up  in  a  straight  line  allowing  at 
least  a  2-foot  aisle  on  all  sides. 

Electronic  Storage  Methods 

Equipment  in  this  category  is  not  cur- 
rently available  for  use  in  American  thea- 
tres and  it  does  not  appear  that  such 
equipment  will  be  available  in  the  im- 
mediate future. 

Two  basic  systems  merit  attention.  The 
first  uses  the  dark  trace  or  Skiatron 
types  of  screens  which  are  known  in  the 
American  market  as  P-10  phosphors. 
Manufacturers  in  this  country  do  not 
plan  in  the  near  future  to  market  a  tube 
which  has  the  proper  characteristics  for 
Tv,  and  some  of  them  express  the  opin- 


Free  Pamphlet 

On  The  Care  Of  Your  Screen 
And   The 

ARCTIC    BLANCH 

Method  Of  Resurfacing  Screens 

NATIONAL  THEATRE  SCREEN 
REFINISHING   COMPANY 

129  Zenner  St.  Buffalo  11,  N.  Y. 


ion  that  this  screen  is  not  feasible  for 
such  use. 

This  fact  is,  of  course,  well  known  to 
the  industry  from  the  results  of  pub- 
lished research  by  many  independent  in- 
vestigators as  well  as  the  engineers  from 
some  of  the  companies  contacted  in  this 
survey.  Generally  speaking,  the  Skia- 
tron tube  at  present  produces  an  image 
which  does  not  permit  sufficient  con- 
trast and  low  persistence  to  compete  suc- 
cessfully with  phosphorescent  screens  or 
with  photographic  emulsions.  It  is  also 
difficult  to  produce  a  screen  which  pro- 
duces true  black  and  whites. 

Similarly,  its  decay  time  is  a  complex 
phenomenon,  and  although  it  can  be 
controlled  to  some  extent  in  manufac- 
ture, satisfactory  performance  in  this  re- 
gard has  not  been  obtained  to  date.  It 
is  entirely  possible,  however,  that  future 
developments  may  reverse  present  think- 
ing in  this  regard. 

Swiss  Storage,  Large-Screen  Method 

The  second  storage  system  is  known 
as  the  AFIF  Method  of  Large-Screen 
Television  Projection.  It  was  developed 
in  Switzerland  by  Dr.  F.  Fisher  at  the 
Swiss  Federal  Institute  of  Technology. 
Since  it  was  known  that  this  system  was 


ANSWER 
TO  YOUR 
TECHNICAL 
PROBLEMS . . . 


The  Altec 
Service  Man  and 
the  organization 
behind  him 


161  Sixth  Avenue, 
New  York  13,  N.  Y. 

PROTECTING  THE  THEATRE— FIRST  PLACE  IN  ENTERTAINMENT 


not  currently  available  for  sale,  no  con- 
tact was  established  with  the  Institute. 
A  laboratory  model  of  a  theatre  pro- 
jector using  this  system  was  demon- 
strated in  Zurich,  Switzerland,  during  the 
week  of  September  5,  1948.  Eye-wit- 
nesses report  that  screen  brightness  was 
equivalent  to  present  motion  picture 
practice  and  picture  definition  was  ade- 
quate for  theatre  use.  The  demonstra- 
tion was  conducted,  however,  using  729 
lines  rather  than  525  currently  stand- 
ard in  the  U.  S.  A. 

Summary  of  SMPE  Report 

It  is  clearly  evident  that  theatre-Tv 
equipment  has  been  developed  which  is 
capable  of  providing  pictures  of  continu- 
ing entertainment  value.  While  not  equal 
in  quality  to  present  35-mm  film,  evi- 
dence has  been  presented  which  indi- 
cates such  quality  will  be  approached  in 
the  future.  Methods  of  distribution  of 
program  material  by  coaxial  cables  or 
radio  channels  also  have  reached  a  stage 
of  development  where  satisfactory  Tv 
pictures  can  be  transmitted  over  neces- 
sary distances. 

Further  development  of  equipment  as 
well  as  provision  by  the  FCC  of  suit- 
able radio  channels  is  now  mainly  de- 
pendent upon  the  interest  shown  by  the 
motion  picture  industry.  Active  partici- 
pation by  theatre  owners  and  related  or- 
ganizations is  essential  if  the  opportunity 
to  use  this  new  medium  is  not  to  be  lost. 

The  FCC,  however,  does  not  grant 
channel  allocations  on  a  vague  request 
that  they  may  be  needed  at  some  future 
date.  Concrete  evidence  must  be  pre- 
sented that  the  group  requesting  such 
allocations  is  prepared  financially  and 
technically  to  provide  a  service  in  the 
public  interest.  Only  by  such  action  can 
it  be  hoped  that  the  request  will  receive 
favorable  consideration. 

The  r-f  spectrum  is  very  rapidly  be- 
coming overcrowded.  If  the  motion  pic- 
ture industry  ever  hopes  to  use  Tv  in 
the  theatre,  action  must  be  taken  now.  A 
year  from  now  may  be  too  late.  Pro- 
ducers, distributors,  and  exhibitors  alike 
must  unite  and  approach  the  FCC  with 
a  well-formulated  plan  that  they  seri- 
ously intend  immediate  experimental  op- 
peration. 

[NOTE:  Copies  of  the  complete  report,  in- 
cluding much  additional  data  relative  to 
governmental  regulations  and  to  various 
facilities  for  transmission  of  programs,  with 
costs  thereof,  -are  available  in  booklet  form 
at  75  cents  per  copy.  Address  the  SMPE, 
342  Madison  Avenue,  New  York  17,  N.  Y.] 


PROJECTIONISTS' 
SERVICE 
MANUAL 


$300 


h 


INTERNATIONAL  PROJECTIONIST     •     March  1949 


'MATCHED'   PROJECTION   OPTICS 

(Continued  from  page  9) 
jection  equipment  are  completed,  speci- 
fic recommendations  should  be  issued. 
Until  such  recommendations  are  made, 
projectionists  and  lens  manufacturers 
will  be  all  but  powerless  to  institute  fur- 
ther improvements  in  the  optical  phase 
of   projection. 

Why  not  employ  the  exact  matching 
speeds  instead  of  arbitrarily  assigned 
optimum  speeds  which,  at  best,  fall  be- 
low ideal  conditions?  The  practical  diffi- 
culties of  manufacturing  and  using  ex- 
tremely large  lenses  are  serious,  almost 
insuperable  obstacles.  Lens  designers 
would  find  their  skills  taxed  to  maintain 
the  necessary  flatness  of  field  and  depth 
of  focus.  A  host  of  troubles  would  de- 
scend upon  the  projection  room,  too,  for 
the  lens  mount  assemblies  of  many  pro- 
jectors would  be  too  small  to  accommo- 
date the  barrels  oi  the  largest  lenses. 

Nevertheless,  il  is  entirely  possible 
that  high-quality  77:1.5  lenses  could  be 
produced  successfully  in  the  shorter  fo- 
cal lengths,  and  these  could  be  used  in 
most  theatres  with  gratifying  screen  re- 
sults. 

Regardless  of  possible  future  innova- 
tions, the  principles  of  matched  optics 
plainly  indicate  the  desirability — yes,  the 
necessity — of  using  nothing  less  than  the 
most  rapid  high-grade  lenses  available  at 
the  present  time.  The  soundness  of  this 
recommendation  cannot  be  disputed,  yet 
thousands  of  theatres  are  still  plodding 
along  with  outmoded  low-speed  lenses. 

Vignetting  Effect  in  Lenses 

Optical  experts  have  long  been  con- 
cerned with  the  so-called  vignetting  effect 
of  projection  lenses.  This  is  a  pronounced 
drop  in  screen  illumination  at  the  edges 
of  the  picture,  and  is  especially  promi- 
nent when  the  older,  low-speed  lenses 
are  used.  When  the  lamp  is  known  to 
illuminate  the  aperture  evenly,  the  cause 
of  the  vignetting  effect  must  be  sought  in 
the  design  and  dimensions  of  the  pro- 
jection lens. 

In  most  cases  the  nature  of  the  light 
beam  pouring  through  the  aperture  is  a 
contributing  factor.    The  central  portion 

New  16-mm   Film  Source  Directory 

Devotees  of  16-mm  films  will  be  in- 
terested in  the  new  Directory  of  Film 
Sources  which  lists  hundreds  of  individ- 
ual basic  sources  of  16-mm  films  divided 
into  five  basic  classifications:  general  in- 
terest, special  interest,  educational,  reli- 
gious, and  entertainment.  Copies  are 
available  at  25  cents  each  from  Radiant 
Screen  Co.,  Chicago. 


BUY  U.  S.  SAVINGS  BONDS 


of  the  lens  "looks"  through  the  aperture 
and  "sees"  the  arc  lamp  mirror  or  con- 
denser beyond  as  a  large  disc  of  intense 
light.  Ordinarily,  however,  the  blazing 
disc  does  not  appear  quite  as  large  as  the 
condensing  element  to  the  "eye"  of  the 
lens,  hence  the  bright  disc  is  surrounded 
by  a  comparatively  dark  ring. 

Now,  the  edges  of  the  projection  lens 
"see"  the  opposite  edges  of  the  condens- 
ing element  through  the  aperture.  To 
the  edges  of  the  lens,  however,  the  edges 
of  the  mirror  or  condenser  are  not  dark 
at  all  but  appear  intensely  bright!  This 
shift  of  the  magnified  crater  image  with 
a  shift  of  viewing  point  (on  the  surface 
of  the  lens)  is  due  in  part  to  aberrations 
of  the  curved  "figure"  of  the  mirror  or 
condenser.  (These  aberrations  also  help 
produce  the  "bend,"  or  bottleneck  form, 
of  the  light  beam  from  a  projection 
lamp.) 

When  a  film  is  projected,  the  center  of 
the  projection  lens  "sees"  a  film  picture 
which  is  very  bright  in  the  middle  but 
dim  at  the  edges.  The  edges  of  the  lens, 
on  the  other  hand,  enjoy  a  rather  differ- 
ent view  of  the  picture.  To  them  the 
overall  illumination  is  less  than  it  is  to 
the  center  of  the  lens,  but  the  edges  of 
the  film  picture  are  the  brightest  parts 
of  all. 

The   several   regions  of  the   lens  pass 


their  "views"  of  the  film  picture  to  the 
screen  where  a  highly  magnified  compo- 
site image  is  formed.  The  central  por- 
tion of  the  screen  image  comes  largely 
from  the  central  portion  of  the  lens,  and 
the    edges    of    the    screen    image    come 


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part  of  my  operation." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


"HOW  IT 
.  WORKS' 


OLD 


STOP 
"Wondering 

About" 
Television 


MINE  OF  PRACTICAL  FACTS 

By  JOHN  F.  RIDER 


Television  is  in  the  eye  of  the  public 
and  in  the  minds  of  everyone  associ- 
ated with  the  motion  picture  industry. 


Here  Are 
The  Facts  on: 

1.  How    TV     Pictures    are 
Produced  and  Sent 

2.  What     is     in     the    TV 
Receiver 

3.  Installation   and 
Orientation   of  TV 
Antennas 

4.  Recognition  of  Troubles 
in   TV   Receivers 

This  book  is  written  in  down-to-earth 
language.  You  don't  have  to  be  an 
engineer  to  understand  it.  The  entire 
book  carries  the  practical  along  with 
the  theoretical. 

203  Pages  Illustrated  $2.70 
Send  Coupon  Below  TODAY! 


.............  ORDER  WITH  THIS   COUPON---- 

International  Projectionist 

19  West  44  St.,  New  York  18,  N.  Y. 

Enclosed  find  $2.70  for  Television  "How  It  Works" 

Name    :..... 

Address    

City 


Zone 


State . 


INTERNATIONAL  PROJECTIONIST 


March   1949 


33 


chiefly  from  the  outermost  edges  of  the 
lens. 

Here  is  the  important  point.  If  the 
projection  lens  be  one  of  those  slow 
"gay  90's"  models,  it  will  fail  to  catch 
most  of  the  light  illuminating  the  edges 
of  the  film  picture,  and  the  screen  image 
will  be  deprived  of  anything  the  lens  is 
unable  to  "see".  The  result  is  a  decided 
vignetting  effect  with  a  "hot  spot"  in  the 
center  of  the  screen.  So  we  see  that  the 
more  closely  our  lenses  are  matched  to 
the  optics  of  your  lamps,  the  more  evenly 
illuminated  will  be  the  picture  we  pro- 
ject. 

Eliminating  the  'Hot  Spot' 

It  would  seem  feasible  to  overcome 
unavoidable,  residual  vignetting  (due  to 
the  impracticability  of  using  perfectly 
matched  optics  in  most  instances)  by 
deliberately  over-parabolizing  the  figure 
of  the  lamp  mirror  or  condensing  lenses. 
The  effect  would  be  an  intensification  of 
edge  brightness  of  the  film  picture  in  the 
aperture.  The  vignetting  effect  would  thus 
be  neutralized  by  an  opposing  "error"  of 
the  lamp  system,  and  the  screen  image 
would    be    smoothly  illuminated. 

The  same  effect  could  be  obtained  by 
the  interposition  of  a  specially  figured 
"compensating  lens"  behind  the  aper- 
ture, but  the  light  loss  in  a  lens  made  of 
heat-resistant  glass  might  be  considered 
too  great  to  be  tolerated. 

Action  by  the  SMPE  on  this  important 
matter  would  seem  to  be  definitely  indi- 
cated. The  "hot  spot"  has  devilled  pro- 
jectionists for  all  too  long! 

The   matter   of  light   dispersion    from 


silver  grains  in  film  emulsion  appears  to 
have  little  bearing  on  picture  illumina- 
tion. I  cannot  find  an  appreciable  effect 
in  the  screen  image  which  can  definitely 
be  attributed  to  dispersion.  It  is  of  in- 
terest to  note  that  dispersion  is  absent 
in  Technicolor  and  other  imbibition- 
process  prints. 


Ultra-Sensitive    Photo    Emulsion 
Requires   Shipment   in    Dry   Ice 

A  new  photographic  emulsion  for  tracking 
down  atomic  particles  is  so  sensitive  its 
producers  are  faced  with  the  problem  of  how 
lo  prevent  its  premature  exposure  by  cosmic 
rays  during  shipment  to  research  workers. 
The  new  emulsion,  developed  in  Kodak  Labo- 
ratories, is  approximately  four  times  as  "fast" 
as  the  company's  existing  nuclear  track 
plates.  It  has  successfully  recorded  electron 
tracks  which  are  ten  times  longer  than  those 
previously    captured    photographically. 

Protection  of  the  new  material  poses  a 
problem  for  Kodak  scientists.  No  sooner  is 
the  new  emulsion  made  than  it  begins  to 
record  the  bombardment  of  cosmic  rays 
which  strike  all  about  us  constantly  from 
outer  space.  „ 

Intense  Cosmic  Ray  Barrage 

Dr.  Cyril  J.  Staud,  director  of  the  labora- 
tories, said  that  "about  six  electrons  from 
cosmic  rays  strike  each  square  cm.  of  the 
emulsion  every  minute."  This  intense  bar- 
rage, he  pointed  out,  peppers  the  emulsion 
so  much  in  three  days  time  that,  unless  ade- 
quately protected,  it  is  clouded  with  back- 
ground  streaks   upon   development. 

Packing  the  emulsion  in  dry  ice  for  ship- 
ment may  protect  it,  Dr.  Staud  indicated, 
because  the  emulsion's  sensitivity  is  reduced 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

INTERNATIONAL    PROJECTIONIST, 
19  West  44  St.,  New  York  18,  N.  Y. 

□  1     year — 12     issues— $2.50 

□  2   years— 24   issues — $4.00 
Foreign  and  Canada:    Add  50c  per   year. 


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ATLANTIC  CITY'S 
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at  low  temperatures.  On  arrival,  it  could  be 
refrigerated  and  later  permitted  to  warm 
up  just  before  exposure. 

Dr.  John  Spence,  in  charge  of  research  on 
the  new  emulsion,  said  that  it  "comes  very 
close  to  complete  recording  of  any  nuclear 
particle."  He  said  the  emulsion  is  charac- 
terized by  a  uniform  sensitivity  of  all  its 
tightly-packed  grains  and  a  high  concentra- 
tion of  silver  halides.  Commenting  on  its 
importance  as  a  photographic  tool  in  nuclear 
research,  Dr.  Spence  explained  that  an 
atomic  particle  in  the  emulsion  acts  like 
a  "skipping  stone"  on  the  surface  of  a  pond. 

Procedure  for  Computing  Data 

"Assuming  one  has  a  good,  round  disc-like 
stone  and  throws  with  precision,"  he  said, 
"the  frequency  of  the  skips  increases  toward 
the  end  of  its  path.  The  faster  the  stone  is 
traveling,  the  less  the  frequency  of  the  skips 
in  the  water.  This  is  paralleled  by  the  pass- 
age of  a  high-energy  particle  through  a  nu- 
clear emulsion.  As  with  the  skipping  stone, 
the  rate  of  energy  loss  is  reflected  in  the 
number  of  grains  along  the  track." 

From  the  length  and  curvature  of  the 
track  and  the  grain-spacing  along  it,  he  said, 
information  is  obtained  of  the  particle's 
speed,  energy,  and  other  characteristics. 

The  emulsion  can  also  bring  new  preci- 
sion to  autoradiography  in  medical  research, 
Dr.  Spence  added.  In  autoradiograhpy,  sec- 
tions of  tissue  containing  radioactive  isotopes 
are  placed  in  contact  with  the  emulsion.  The 
specimen  takes  its  own  picture  when  radia- 
tion from  its  tissue  exposes  the  emulsion. 
Examination  of  the  developed  plate  enables 
scientists  to  identify  the  location  and  amount 
of  radioactive  penetration  in  the  tissue. 

The  new  material  has  been  made  so  far 
only  on  an  experimental  basis  and  is  not  yet 
generally  available. 


34 


INTERNATIONAL  PROJECTIONIST 


March  1949 


SO  MUCH 


for  so  LITTLE 


$0.00 


3 


per  copy 
pottage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


4  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


S&nd 


(Do  That  (Ddeuf 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18.  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a   copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
Name  _ 


Address 
City    


State 


•  v»B«■asw», 


MANUFACTURED    BY    INTERNA 


PROJECTION  AND  SOUND  SYSTEMS 


TIONAL    PROJECTOR     CORPORATION    .    BLOOMFIELD,    NEW    JERSEY 


m 


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A        ft  I. 


'«rf~  rWT.>rrM,o 


Mf*** .'  t  tJt 


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APRIL 


1949 


VOLUME  24       •       NUMBER  4 


30c  A  COPY    •    S2.50  A  YEAR 


"Buy  U.  S.  Savings  Bonds 
during  the  Opportunity  Drive," 

SAY     THESE     LEADING     AMERICANS 


WINTHROP    W.  ALDRICH,  Chairman, 
Chase  National  Bank 


PHILIP    MURRAY,  President, 
Congress  of  Industrial  Organizations 


"For  the  working  man,  an  increased  in- 
vestment in  U.  S.  Savings  Bonds  can  mean 
not  only  increased  security  but  increased 
ability  to  take  advantage  of  the  opportunities 
that  are  part  of  the  American  way  of  life." 


"I  believe  that  every  individual  who  can 
possibly  do  so  should  buy  more  U.  S.  Savings 
Bonds.  These  bonds  represent  one  of  the 
best  investments  of  our  time." 


"The  C.I.O.  has  endorsed  every  effort  to 
encourage  the  worker  to  put  more  of  his 
earnings  into  U.  S.  Savings  Bonds.  They  rep- 
resent both  security  and  independence."  -. 


CHARLES   F.  BRANNAN 

Secretary  of  Agriculture 


"I  am  heartily  in  favor  of  the  Opportunity 
Drive  to  buy  more  U.  S.  Savings  Bonds. 
Everyone  engaged  in  farming  should  recog- 
nize the  importance  of  a  backlog  of  invested 
savings  as  a  means  of  realizing  the  agricul- 
tural opportunities  of  the  future." 


During  May  and  June,  the  U.  S.  Savings  Bond  Oppor- 
tunity Drive  is  on ! 

It  is  called  the  Opportunity  Drive  — because  it  is  truly  an 
opportunity  for  you  to  get  ahead  by  increasing  your  own  per- 
sonal measure  of  financial  security  and  independence. 

If  you  haven't  been  buying  Savings  Bonds  regularly,  start 
now. 

If  you  have  been  buying  them,  add  an  extra  Bond  or  two  to 
your  purchases  this  month  and  next.  Remember— you'll  get 
back  $4  for  every  $3  in  a  short  ten  years'  time  ! 

Put  More  Opportunity 
in  Your  Future . . . 
INVEST  IN  U.  S.  SAVINGS  BONDS 


Contributed  by  this  magazine  in  cooperation  with  the 
Magazine  Publishers  oj  America  as  a  public  service. 


^> 


:vt$'£: 


*x 


I 


'■>**!> 


5 


THE  STRONG  MOGUL 

PROJECTION      ARC      LAMP 

PROJECTS  THE  MAXIMUM  LIGHT  THAT  FILM  WILL   ACCEPT  WITHOUT  DAMAGE 


USE  THIS  COUPON  TODAY  FOR  DEMONSTRATION  OR  LITERATURE 


|.  THE  STRONG  ELECTRIC  CORPORATION 

I'  "The  World's  Largest  Manufacturer  of  Projection  Arc  Lamps" 
|    31   City  Park  Avenue  Toledo  2,  Ohio 

f~|  I  would  like  a  demonstration  of  Strong  lamps  in  my  theatre,  without  cost 
or  obligation. 
Please  send  free  literature  on  the: 

□  Mogul  Lamp  Q  Utility  1  K.W.H.I.  Lamp  □  Strong  Rectifiers 

3  Strong  Reflectors  Q  Strong  Arc  Spotlamps 

NAME — 


STRONG  ^/Muvtyfr/ 


THEATRE- 
STREET — 


CITY  AND  STATE- 


m^S^f^/n/mi^&rk^^Jsee! 


THESE  jumbo  screens  used  in  big,  drive-in 
theatres  require  projection  light  of  terrific 
brilliance.  Otherwise,  your  patrons  can't  get 
that  bright-screen  sparkle  they  are  used  to  in 
first-run,  conventional  theatres.  They  have  to 
squint  to  see. 

Give  your  patrons  vivid,  easy-to-see  pictures 
by  using  "National"  Super-High  Intensity 
carbons  in  your  drive-in  theatre.  These  carbons 
give  you  brighter  light  than  any  other  source 
of  projection  light  obtainable.  And,  because 
"National"  Super-High  Intensity  carbons  pro- 
duce light  of  almost  perfect  color  balance, 


your  color  movies  glow  with  rich  detail. 

The  slight  extra  cost  of  "National"  Super- 
High  Intensity  carbons  is  negligible  when  you 
consider  the  advantages  in  audience  approval 
and  bigger  box  office.  Write  for  complete 
details. 

The  term  "National"  is  a  registered  trade-mark  of 
NATIONAL  CARBON    COMPANY,   INC. 

Unit  of  Union  Carbide  and  Carbon  Corporation 

GH3 

30  East  42nd  Street,  New  York  17,  N.  Y. 

DivisionSales  Offices:  Atlanta,  Chicago,  Dallas,  Kansas  City, 

New  York,  Pittsburgh,  San  Francisco 


Use  "National"  Super -High  Intensity  carbons  for  "the  brightest  spot  in  the  world.' 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


INTERNATIONAL 


OJECTH 


With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


APRIL  1949 


Number  4 


Index  and  Monthly  Chat 5 

Projection  Preparations  for  the 

'Seasonal'  Theatre   7 

R.  A.  Mitchell 

The  Use  of  Films  in  Television     12 
SMPE  Progress  Report 

Precise  Calibration  of  Lens 

Markings     15 

Notes  Anent  the  Simplex  E-7 

Double-Film   Attachment    ...      15 

SMPE  Convention  Roundup    .  .      16 


Letter  to  the  Editor — on  the 
Square     


17 


In  the  Spotlight   18 

Harry  Sherman 

Unique  Method  of  Alternate- 
Frame  16-mm  Projection  20 

H:  Hill 

Personal   Notes    20 

Lens  Design  and  Manufacture       21 
A.  Howard  Anstis 

Telecasts      23 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL   PROJECTIONIST   PUBLISHING   CO.,   INC. 

19  West  44  Street,  New   York   18,  N.   Y. 

R.   A.    ENTRACHT,   Publisher 

SUBSCRIPTION   REPRESENTATIVES 

AUSTRALIA:  McGills,  183  Elizabeth  St.,  Melbourne 

NEW  ZEALAND:  Te  Aro  Book  Depot,  Ltd.,  64  Courtenay  Place,  Wellington 

ENGLAND  and  DOMINIONS:  Wm.  Dawson  &  Sons.  Ltd.,   Macklin  St.,  London,  W.  C.  2 

Yearly  Subscription:  United  States  and  possessions,  $2.50  (two  years,  $4);  Canada  and 
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two  weeks  in  advance  of  publication  date  to  insure  receipt  of  current  issue.  Entered  as 
second-class  matter  February  8.  1932.  at  the  Post  Office  at  New  York,  N.  Y..  under  the 
act  of  March  3,  1879.  Entire  contents  copyrighted  1949  by  International  Projectionist 
Publishing  Co..  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


>420 


MONTHLY    CHAT 


TO  THOSE  still  cherishing  the  illusion 
that  motion  pictures  is  a  static  art, 
with  all  the  technological  returns  being 
in  and  with  every  prospect  that  the 
future  will  witness  no  radical  departure 
from  existing  equipment  and  technique, 
the  proceedings  at  the  recent  SMPE  Con- 
vention would  prove  an  eye-opener.  Par- 
ticularly is  this  true  of  the  exhibition 
field,  wherein  not  only  brand  new  proc- 
esses but  a  radical  change  in  equipment 
and  technique  are  forecast. 

Most  interesting  to  us  was  the  frontal 
assault  made  by  the  16-mm  boys  on  the 
35-mm  citadel.  No  longer  content  with 
the  more  or  less  self-imposed  restriction 
as  to  frequency  range,  the  16-mm  people 
took  the  wraps  off  product  which  visually 
and  aurally  would  give  a  good  35-mm 
picture  a  tough  tussle.  We  may  expect 
to  see  a  gradual  extension  of  16-mm  ap- 
plication to  the  professional  field,  with 
reduction  prints  finding  increasing  ap- 
plication. 

Let  us  not  forget  that  the  bulk  of  mo- 
tion picture  theatres  have  less  than  1000 
seats,  however  much  publicity  accrues  to 
the  de  luxe  operations,  and  it  is  in  the 
former  classification  that  the  16-mm 
people  will  make  their  most  strenuous 
efforts. 

Then  there  is  the  matter  of  tape  re- 
cording and  reproduction.  Already  ex- 
tensively used  in  the  studios,  it  wouldn't 
surprise  us  at  all  to  witness  an  expand- 
ing use  for  this  equipment  which  would 
precipitate  it  right  into  the  theatre  field. 
Quality-wise,  this  tape  process  is  at  least 
as  good  as  the  best  film  recording.  Just 
what  form  this  application  will  take  is 
not  clear  at  the  moment,  but  if  stereo- 
phonic sound  ever  comes  into  its  own, 
then  this  tape  will  really  go  to  town. 

Television,  of  course,  was  the  big  noise 
at  the  Convention,  and  while  it  was  ob- 
vious that  much  improvement  has  been 
effected  in  both  equipment  and  tech- 
nique during  the  past  half-year,  we  still 
are  a  bit  hazy  as  to  just  where  Mr.  Pro- 
jectionist will  fit  into  the  general  scheme 
of  things.  It  is  by  no  means  certain  that 
the  Tv  equipment  will  be  installed  in  the 
projection  room,  which  means  that  con- 
siderable tugging  and  hauling  jurisdic- 
tion-wise is  almost  inevitable.  Due  for 
revival  is  the  old  saw  about  "qualified 
engineering  personnel,"  which  may  be 
freely  translated  into  one  term:  non- 
union. 

Yes,  indeed,  the  technological  pot  is 
boibng  (there  are  other  developments 
which  still  are  in  the  "mum"  stage  but 
which  are  virtually  set  to  go)  ;  and  what- 
ever course  is  followed  in  introducing 
these  developments,  the  projectionist 
craft  has  the  two-sided  task  of  preparing 
itself  by  acquiring  technical  savvy  as  a 
means  of  protecting  those  interests  which 
they  have  built  up  so  arduously  through 
the  years. 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


^W^  twembetftf 


AND  YOU'LL  WANT  IT  IN  YOUR  BOOTH 


•  Projectionists,  who  know  and  use  the  BRENKERT 
"60,"  are  active  enthusiasts  for  this  new  projector.  Their 
applause  is  not  only  for  the  BRENKERT  "60's"  superb 
engineering,  but  also  because  it  keeps  the  "show"  going 


continuously,  thus  making  the  projectionist's  job  easier. 
The  BRENKERT  "60"  has  proved  itself— by  supplying 
excellent  projection— by  being  more  economical— by 
requiring  less  attention  than  other  projectors. 


Automatic  Lubrication.  All  moving  parts  on  the  gear 
side  of  the  projector  are  literally  showered  with  oil. 
A  continuous  stream  of  oil  circulates  along  the  entire 
length  of  the  bearings,  over  shafts  and  gears,  including 
the  intermittent  mechanism.  Lubrication  is  automatic- 
no  hand  oiling  required. 

Brenkert's  positive  lubrication  provides  free  opera- 
tion of  moving  parts.  The  circulating  oil  keeps  the 
projector  mechanism  cool.  No  wonder  Brenkert  pro- 
jectors give  lasting  high-quality  performance,  longer 
wearing  of  all  parts  and  low  upkeep  costs! 

Wide-Mesh,  Heavy-Duty  Gearing.  Large  gears  of 
yg-inch  thickness  assure  closer  fit  over  a  greater  contact 
area  than  gears  used  on  other  projectors.  Gear  teeth 
are  cut  on  an  angle  for  greater  radial  accuracy,  smoother 
and  quieter  operation,  more  dependable  performance. 
Brenkert  gears  last  longer,  and  their  maintenance  costs 
are  lower. 

Unit  Construction.  Various  projector  sub-assemblies  are 
removable  as  separate  units.  They  are  doweled  to  the 
main  frame  for  correct  and  easy  alignment.  This  makes 
possible  quick  and  accurate  servicing,  requires  less 
time  for  maintenance. 

Sturdy,  Intermittent.  Brenkert  intermittents  are  made 
within  an  accuracy  of  1/10,000  of  an  inch.  These  pre- 
cise dimensions  provide  the  highest  quality  projection, 
trouble-free  performance,  and  lowest  maintenance 
cost.  The  large  intermittent  bearing  area  assures  rock- 
steady, accurate  projection  throughout  its  long  life. 

The  BRENKERT  "60"  can  be  adapted  to  all  standard 
sound-heads,  arc  lamps,  pedestals  and  film  magazines. 
It  provides  medium  size  and  small  size  theatres  with 
highest-quality  projection  at  low  cost. 


Operating  side  of  BRENKERT  "60"  Projec- 
tor. Note  roomy  operating  compartment  and 
ample  space  for  easy  threading  and  cleaning. 


WRITE  FOR  THIS  BOOKLET 
It's  yours  for  the  asking! 

Send  for  free  copy  of  the  new 
booklet  illustrating  and  describ- 
ing the  operating  mechanism  of 
the  Brenkert  "60"  Projector.  Write 
to  Theatre  Equipment,  Dept.  47-D, 
RCA,  Camden,  N.J. 


THEATRE  EQUIPMENT 

RAD tO    CORPORATION  of  AMERICA 

ENGINEERING  PRODUCTS  DEPARTMENT,  CAMDEN  N.J. 

In  Canada:  RCA  VICTOR  Company  limited,  Montreal 


VOLUME  XXIV 


APRIL  1949 


NUMBER  4 


Projection  Preparations  for 
the   Seasonal'  Theatre 

Copyright  1949  by  INTERNATIONAL   PROJECTIONIST.    Reproduction  forbidden. 


THE  term  "summer  theatre"  when  used 
in  connection  with  motion  pictures 
denotes  an  exhibition  operation  provid- 
ing screen  entertainment  during  the  sum- 
mer vacation  season.  These  operations 
may  be  divided  into  three  main  classes: 

(1)  "Permanent"  theatres  which  are 
operated  only  during  the  summer 
months  because  winter  operation 
is  unprofitable. 

(2)  "Temporary"  motion  picture  in- 
stallations, among  which  are 
found  open-air  tents,  concert 
halls,  and  dance  pavilions  pressed 
into  service  as  cinemas. 

(3)  Drive-in  theatres. 

Drive-in  theatres  are  usually  perman- 
ent in  that  the  projection  equipment  is 
not  removed  at  the  close  of  the  season. 
The  "temporary"  venture  often  employs 
motion  pictures  as  a  filler  for  open  dates 
between  concerts  and  stage  shows.  The 
"permanent"  type  of  summer  theatre  is 
the  most  conventional,  but  the  presenta- 
tions consist  largely  of  first-run,  top- 
quality  productions  on  single-feature  bills 
with  selected  short  subjects. 

The  operational  policy,  in  general,  is 
conservative  and   dignified. 

Projectionists  in  most  summer-resort 
theatres  are  required  to  close  down  at 
the  end  of  the  first  evening  show  for  an 
intermission — a  convenience  for  waiting 
second-show    patrons    who    find    that    a 


By  ROBERT  A.  MITCHELL 

This  article,  although  pointed  at  the 
'seasonal'  theatre,  is  applicable  in 
almost  all  particulars  to  any  type  of 
motion  picture  projection  installation. 
In  fact,  it  is  an  invaluable  guide  for  a 
general  overhaul  of  all  such  facilities. 

"preview"  of  the  last  few  scenes  of  the 
feature  picture  spoils  their  enjoyment  of 
the  show.  Starting  times  of  shows  are 
seldom  delayed,  except  in  the  case  of  re- 
served-seat performances. 

Flawless  projection  is  expected  at  all 
times,  of  course,  but  the  "unseen  show- 
man" is  all  too  frequently  handicapped 
by  worn  and  obsolete  equipment. 

Reopening  Tasks  Formidable 

A  truly  formidable  number  of  tasks 
await  the  projectionist  who  must  open  a 
theatre  which  has  been  closed  for  a  con- 
siderable length  of  time.  To  neglect 
any  of  them  is  to  invite  film  breaks,  light 
failures  and  sound-system  troubles.  The 
skill,  experience,  and  reputation  of  the 
projectionist  are  put  to  the  test  of  pre- 
conceived standards  from  the  outset. 
Failure  to  achieve  acceptable  screen 
results  will  discredit  him.     Ample  time 


must  be  allowed  to  line  up  the  projection 
and  sound  equipment  prior  to  opening. 

Certain  legal  aspects  of  such  opera- 
tions affect  the  projectionist  and  must  be 
considered  before  anything  else.  No 
matter  what  the  type  of  theatre,  its 
projection  facilities  must  meet  the 
specifications  of  State  and  municipal 
ordnances.  At  the  present  time  Con- 
necticut, Maine,  and  Massachusetts  are 
the  only  states  in  New  England  having 
comprehensive  theatre  laws  and  requiring 
the  licensing  of  projectionists.  New 
England  has  a  large  concentration  of 
summer  theatres.  Examinations  for  pro- 
jection licenses  cover  the  following  six 
points: 

(1)     Handling  of  the  head,  lamp,  ap- 
pliances, and  wiring  of  the  pro- 
jection  equipment. 
Practical    testing    for    electrical 
defects  in  the  lamp  and  wiring 
in  the  projection  room. 
Use  of  the  safety  appliances  in 
the  projection  room. 
Film-handling  precautions. 
Laws  and  regulations  governing 
motion  picture  projection. 
Projection    demonstration    in    a 
theatre. 
Legal  requirements  having  been  met, 
the  projectionist  is  free  to   proceed  di- 
rectly   to    the    equipment,    and    for   this 
work  a  systematic,  step-by-step  servicing 


(2) 


(3) 

(4) 
(5) 

(6) 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


plan  is  helpful.  It  is  only  by  exercising 
the  utmost  care  in  checking  and  lining  up 
that  the  projectionist  can  be  sure  that  all 
units  have  been  covered  thoroughly,  and 
that  the  all-important  opening  show  will 
run  smoothly  and  with  professional 
"snap." 

The  following  suggested  plan  has  been 
devised  with  the  very  ivorst  conditions  in 
mind.  Specific  instructions  for  checking 
various  projector  adjustments  were  out- 
lined in  "Notes  on  Projector  Mainten- 
ance" (IP  for  August,  1948,  p.  6),  hence 
only  the  details  of  systematic  inspection 
and  servicing  are  treated  at  length  in 
this  article.  The  principal  steps  of  the 
plan  are  numbered  and  headed  to  facili- 
tate reference. 

Inspection,  Servicing  Plan 

1.  Preliminary  Cleaning.  Do  not 
switch  projector  motor  on  at  this  time! 
Dust  off  the  exterior  surfaces  of  each 
projector,  lamp,  magazines,  head,  motor, 
and  pedestal.  Wipe  the  rust-preventive 
grease  from  all  exterior  and  interior 
parts,  and  remove  rust  spots  with  a  small 
cloth  wet  with  kerosene.  Dry  thoroughly, 
apply  a  thin  film  of  projector  oil  to  the 
parts  cleaned,  and  again  wipe  dry.  (Do 
not  use  cotton  mechanic's  waste  for 
cleaning  projectors.) 

2.  Cleaning  Drives  and  Gears.  At- 
tention will  now  be  directed  to  the  drive 
side  of  the  machine.  Remove  excess  oil 
from  the  mechanism  and  soundhead, 
using  a  medicine  dropper  to  drain  off  oil 
pools;  afterward  clean  rags.  Scrub  off 
accumulations  of  grime  from  the  gears 
with  a  stiff-bristled  toothbrush  dipped  in 
kerosene.  Be  sure  to  wipe  the  kerosene 
off  afterward.  Check  all  machine  screws 
and  taper-pins.  This  is  the  time  to 
requisition  gears  and  other  parts  which 
need  to  be  replaced.  Do  not  oil  the  pro- 
jector yet. 

3.  Checking  the  Intermittent. 
Test  the  intermittent  sprocket  for  end- 
play  and  backlash  when  in  the  locked 
position.  Note  the  "feel"  of  the  mecha- 
nism when  the  machine  is  turned  by  hand. 
If  there  are  no  evidences  of  binding,  the 
motor  may  be  run  for  short  periods.  With 
the  machine  running,  listen  carefully  to 
the  intermittent  movement  with  the  film 
gate  open.  A  noisy  intermittent  unit 
must  be  taken  out  of  the  head,  carefully 
examined  for  wear,  and  adjusted  for 
noiseless,  rock-steady  operation. 

4.  Checking  the  Film  Course.  Re- 
move the  upper  magazine.  Clean  thor- 
oughly all  parts  of  the  film  side  of  the 
projection  and  sound  heads,  using  kero- 
sene as  a  cleaning  agent.  Carbon  tetra- 
chloride may  be  used  to  loosen  stubborn 
dirt  deposits.  A  quantity  of  clean  rags,  a 
toothbrush,  and  a  copper-wire  probe  are 
indispensable.  The  gate  door,  the  aper- 
ture plate,  and  the  projection  lens  should 
be    taken    out.    and    the    lens    carefully 


Typical  State  Regulations 

Copies  of  State  theatre  laws  may  be  ob- 
tained free  of  charge  by  writing  to  the 
proper  authorities. 

CONNECTICUT.  Rules  and  Regulations  Governing 
Picture  Exhibitions.  Address:  Department  of  Connecti- 
cut State  Police.  State  Police  Headquarters,  Hartford, 
Connecticut. 

MAINE.  Statutes  and  Rules  and  Regulations  Relat- 
ing to  Moving  Picture  Theatres.  Address:  State  of 
Maine  Insurance  Department,  State  House,  Augtista, 
Maine. 

MASSACHUSETTS.  Laws.  Rules  and  Regulations 
Governing  the  Use  of  the  Cinematograph  and  Similar 
Apparatus  for  the  Exhibition  of  Motion  Pictures.  Ad- 
dress: Massachusetts  Department  of  Public  Safety, 
State  House,   Boston.  Massachusetts. 


placed  in  the  cabinet  for  cleaning  at  a 
later  time. 

Check  all  sprockets  for  worn  or  burred 
teeth.  The  intermittent  and  sound  sprock- 
ets are  likely  to  be  the  worst,  as  these 
are  the  most  difficult  to  remove.  Reverse 
or,  better,  replace  sprockets  having  worn 
teeth. 

Examine  idlers  and  pad  rollers  for 
wear  and  adjustment.  The  lateral  and 
clearance  adjustments  of  pad  rollers  are 
sufficiently  important  to  warrant  a  re- 
view of  maintenance  notes  thereon. 

Thread  a  short  strip  of  new  film  over 
the  sprocket.  Open  and  close  the  pad 
roller  several  times  rather  sharply.  Re- 
move the  film  strip  and  examine  its  edges 
at  the  place  where  it  was  on  the  sprocket. 
If  an  edge  is  found  to  be  nicked  or 
roughened,  loosen  the  set-screw  and  move 
the  pad-roller  arm  in  or  out,  as  required, 
and  tighten.  Repeat  the  test  until  a  posi- 
tion is  found  where  the  edges  of  the  film 
are  not  injured  by  opening  and  closing 
the  pad  roller. 

Thread  the  sprocket  with  two  thick- 
nesses of  film  and  close  the  pad  roller. 
Adjust  the  stop-screw  until  the  point  is 
reached  where  the  two  thicknesses  of 
film  are  only  very  slightly  loose  on  the 


sprocket  with  the  pad  roller  closed.  Then 
tighten  the  locknut. 

Clean  the  aperture  plate  and  gate  door, 
adjust  the  tension  of  the  pressure  pads, 
if  necessary,  and  return  these  parts  to 
the  machine.  A  thin  film  of  heavy  petro- 
latum may  be  rubbed  on  the  film  tracks 
and  pressure  pads.  (Oil  should  not  be 
used  in  the  gate,  as  heat  will  vaporize  it 
and  fog  the  lens.) 

The  gates  of  old-style  soundheads  and 
the  takeoff  drums  of  newe*  models  may 
now  be  cleaned.  Petrolatum  is  unnec- 
essary here.  The  focus  of  the  optical 
tube  should  not  be  disturbed  if  this  is 
known  to  be  correct.  (More  anon  con- 
cerning this  point.) 

Check  the  alignment  of  the  intermit- 
tent sprocket  shoe  by  slowly  closing  the 
gate  while  the  projector  is  running.  If 
a  loud  intermittent  sound  is  heard  only 
when  the  gate  is  closed,  adjustments  are 
necessary. 

Examine  the  lateral  guide  rollers  for 
condition  and  cleanliness,  but  the  ad- 
justment of  these  must  wait  until  the  pic- 
ture projection  test  is  made.  Clean  and 
correct  the  position  of  sprocket  strippers. 

Finally,  thread  up  a  10-foot  length  of 
film — preferably  a  strip  containing  sev- 
eral wide  and  badly  buckled  splices — 
and  run  down  slowly  by  hand,  noting  the 
action  of  the  loops  and  the  passage  of 
the  film  over  the  sprockets.  Correct  any 
faults  which  may  be  revealed  by  this  test. 

5.  Upper  Magazine.  The  upper  maga- 
zine should  be  overhauled  before  replace- 
ment on  the  projector.  Take  the  assem- 
bly completely  apart,  clean  and  oil  the 
spindle  shaft,  then  reassemble.  Clean  the 
fire-valve  rollers.  Put  the  magazine  back 
on  the  machine  in  correct  alignment  with 
the  head.  Check  the  assembly  by  placing 
an  empty  2000-foot  reel  in  the  upper 
magazine  and  turning  it  while  pressing 
in  on  the  edge  of  the  reel.    Scraping  of 


I 


VISUAL  AND   SOUND   PROJECTION    UNITS   IN    MODERN    DRIVE-IN    THEATRE 


8 


INTERNATIONAL  PROJECTIONIST 


April  1949 


Thanks  to  the  newsreel  editor  •  •  • 

the  world  passes  in  review 

To  his  objectivity  .  .  .  his  sense  of 
the  newsworthy  .  .  .  his  feeling  for 
concise  and  graphic  storytelling  .  .  . 
the  newsreel  owes  its  unique  place 
in  American  journalism. 

Yet  the  newsreel  editor  would  be 
the  first  to  give  due  credit  to  his  staff 
of  cameramen  . . .  and  to  the  family  of 
Eastman  motion  picture  films  which 
help  them  cover  the  news — and  help 
him  present  it  so  effectively. 


ACROSS  his  "front  pages,"  before 
the  eyes  of  movie-goers  on  Main 
Streets  everywhere,  the  world  passes 
in  review.  There,  North  meets  South, 
East  meets  West  through  the  special- 
ized efforts  of  the  newsreel  editor. 

He  sifts  the  facts  and  foibles  of  the 
world  .  .  .  presents  in  one  short  reel 
the  significant,  the  human,  and  the 
odd — news  that  helps  the  world  to 
know  itself  better. 


EASTMAN    KODAK    COMPANY 

ROCHESTER     4,     N.     Y. 

J.    E.    BRULATOUR,    INC.,    DISTRIBUTORS 
FORT     LEE     •     CHICAGO     •     HOLLYWOOD 


the  reel  against  any  part  of  the  magazine 
indicates  a  condition  to  be  corrected. 

Now  test  the  tension  of  the  friction 
spring  by  spinning  a  fully  loaded  2000- 
foot  reel  in  the  magazine.  The  reel  should 
not  run  too  freely. 

6.  Lower  Magazine  and  Takeup 
Assembly.  It  is  highly  advisable  to  serv- 
ice thoroughly  the  lower-magazine  takeup 
assembly  of  any  projector  which  has  been 
idle  for  a  considerable  length  of  time. 

Replace  the  takeup  belt  with  a  new 
one,  if  frayed  and  oil-soaked.  Tighten 
loose  belts,  as  slippage  causes  irregular 
takeup  action.  Replace  belts  having 
more  than  one  splice  or  coupling. 

Disassemble  the  takeup  assembly.  In- 
spect all  parts  for  wear.  Clean  and  oil 
the  takeup  spindle  shaft.  Scrub  the 
clutch  surfaces  with  carbon  tetrachloride 
and  do  not  oil  them.  Wash  dirt  and  oil 
from  the  leather  friction  disk  with  carbon 
tetrachloride,  dry  thoroughly,  and  oil 
only  one  side. 

Reassemble  the  takeup  and  adjust  the 
tension  to  the  correct  degree.  This  may 
be  done  by  placing  a  fully-loaded  2000- 
foot  reel  of  film  in  the  lower  magazine 
and  switching  on  the  projector  motor. 
The  reel  should  indeed  turn  (start  turn- 
ing of  its  own  accord),  but  it  should  also 
be  easily  restrained. 

7.  Complete  Lubrication.  Oil  and 
grease  the  motor,  drive  transmission,  pro- 
jector mechanism,  and  soundhead  accord- 
ing to  manufacturers'  instructions,  using 
the  proper  type  of  lubricant  in  every  case 
Drain  the  intermittent  well  and  refill  with 
fresh  oil,  if  this  has  not  already  been 
done.  Run-in  the  projector  for  30  minutes 
and  note  the  "feel"  of  the  machine  after- 
wards. 

8.  Automatic  Fire  Shutter.  The 
projectionist  should  assure  himself  that 
the  lifting  and  dropping  action  of  the 
safety  shutter  is  perfect.  When  checking 
this  device  by  switching  the  motor  on 
and  off,  do  not  turn  the  motor  on  while 
the  projector  is  coasting  to  a  standstill. 
In  other  words,  wait  until  the  machine  is 
absolutely  motionless  before  turning  the 
motor  on  again.  Failure  to  observe  this 
precaution  may  result  in  injury  to  the 
gears. 

(The  timing  of  the  occulting  shutter 


Warning:  Correct  Width  of 
Adjustable  Shutter  Blades 

Shutters  having  blades  of  adjustable 
width  need  special  attention.  It  has 
been  stated  incorrectly  in  a  well-known 
textbook  on  projection  that  the  lens  may 
be  about  one-third  open  when  the  inter- 
mittent sprocket  starts  to  move  and  the 
same  distance  open  when  the  sprocket 
comes  to  rest,  without  affecting  the 
screen  image. 

This  inconceivably  bad  practice  is 
advocated  as  an  effective  measure  for 
increasing  screen  illumination. 

Actual  projection  tests  prove  that  the 
extra  illumination  amounts  to  only  2 
or  3  %  — an  amount  imperceptible  to  the 
average  eye.  The  really  important  effect, 
however,  is  the  introduction  of  an  an- 
noying rapid  trembling  of  the  edges  of 
all  bright  objects  in  the  screen  image. 

We  are  forced  to  conclude,  therefore, 
that  the  occultation  of  the  film  image 
must  be  positively  of  sufficient  duration 
to  keep  the  screen  dark  during  the  en- 
tire interval  of  the  film  movement  in  the 
gate.  It  is  decidedly  better  to  have  the 
blades  a  trifle  too  wide  than  too  narrow. 


will  be  left  until  projection  tests  are  con- 
ducted. It  suffices  for  the  present  to  see 
to  it  that  undue  backlash  and  endplay  are 
eliminated  from  the  shutter  shaft,  and 
that  all  the  bearings  have  received  proper 
lubrication.) 

9.  Motor  Check.  The  starting  ac- 
tion of  the  projector  motor  is  an  ex- 
tremely important  consideration.  A 
faulty  cutout  or  centrifugal  switch  must 
be  corrected  at  this  time.  All  electrical 
connections  are  examined — the  starting 
rheostat  requiring  special  attention — and, 
of  course,  more  than  a  passing  glance 
must  be  given  the  motor  switch.  An  un- 
duly loose  or  otherwise  defective  switch 
should  be  replaced,  and  no  attempt  made 
to  repair  it. 

Watch  for  evidences  of  strain,  excessive 
current  consumption,  and  excessive  heat- 
ing. 

10.  Film-Flow  Test.  This  step  serves 
as  a  final  check  on  the  mechanical  func- 
tioning of  the  projector.  Neither  picture 
nor  sound  is  projected  at  this  time. 


Typical 

drive-in 

theatre 

layout  with 

modern 
screen  tower. 
Projection 
room  shown 
at  extreme 
left-center. 


Thread  up  the  projector  with  a  reel  of 
film  and  run  it  off  with  magazine,  mecha- 
nism, and  soundhead  doors  open.  Ob- 
serve the  flow  of  the  film  and  the  action 
of  all  working  parts  on  the  film  side  of 
the  machine.  If  minor  defects  are  dis- 
covered, they  are  now  corrected.  The 
film-flow  test  also  provides  an  opportu- 
nity to  ascertain  the  pickup  time  of  the 
loaded  projector. 

11.  Projection  Lens.  The  projection 
lens  is  now  carefully  cleaned  and  re- 
stored to  the  projector.  For  the  correct 
methods  of  cleaning  lenses  refer  to 
"Coated  Lenses:  Nature  and  Care"  by 
A.  E.  Murray  of  the  Bausch  &  Lomb 
Optical  Company  (IP  for  February,  1949, 
p.  7).  So  comprehensive  is  Dr.  Murray's 
contribution  to  this  phase  of  the  projec- 
tion art,  that  the  subject  is  dismissed 
here  with  the  oft-repeated  admonition: 

NEVER  "scrub"  lenses;  NEVER  wash 
lenses  in  alcohol  or  other  organic  sol- 
vents! Failure  to  heed  this  warning  may 
ruin  a  fine  lens. 

12.  Lamp  and  Ventilating  System. 
The  interior  of  the  arc  lamp  may  be  so 
dirty  that  much  time  and  effort  will  be 
required  to  clean  it  out.  The  presence 
of  carbon  stubs  in  the  carbon  holders  is 
mute  evidence  of  the  laxity  of  the  projec- 
tionist's predecessor. 

If  the  vent  pipes  appear  to  be  clogged 
with  carbon  dust  and  oxide  fluff,  take 
them  down  and  clean  them  before  clean- 
ing the  lamps.  In  any  event,  the  effec- 
tiveness of  the  ventilating  system  should 
be  tested  long  before  an  arc  is  struck. 
Invisible  gases  produced  by  electric  arcs 
are  highly  poisonous. 

As  a  rule,  low-intensity  get  grimier 
than  high-intensity  lamps.  Oil-caked 
carbon  encrustations  are  frequently  the 
cause  of  faulty  mechanical  action.  The 
roof  of  the  lamp  should  be  cleaned  first, 
and  all  ash  removed  from  the  vent.  Then 
the  floor  may  be  brushed  free  of  dust. 
Grease,  graphite  accumulations,  etc.,  may 
be  washed  with  kerosene  from  the  guide 
rods,  feeding  screws,  and  reflector  gear- 
ing. After  cleaning,  lubricate  all  moving 
parts  of  the  lamp  according  to  the  manu- 
facturer's instructions. 

13.  Lamp  Electrical  Appliances. 
Burnish  the  contact  surfaces  of  the  car- 
bon holders.  If  light  filing  is  necessary, 
use  a  magneto  file,  taking  care  to  pre- 
serve the  flatness  of  the  surfaces.  Then 
give  them  a-  final  polishing  with  crocus 
cloth.  Test  the  clamping  action  of  the 
carbon  jaws,  and  give  rotating-positive 
feeds  extra  attention. 

Electrical  connections  to  the  carbon 
holders,  arc  relay,  feed  motor,  etc.,  must 
be  secure.  It  is  not  uncommon  for  as 
much  as  3  amperes  to  be  lost  through 
faulty  carbon-holder  lug  connections. 
The  lost  current  is  converted  into  heat 
which  aggravates  the  trouble  by  acceler- 
(Continued  on  page  33) 


10 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


foot 


af/O 


choose 


lyJAGNARC 


TRADE     MARK    REG. 


1-KW  TO  70  AMPS 

The  "1-KW"  Special  is  a  man-sized  lamp  priced  to  meet  "Pee-wee"  lamp 
competition.  .  .  .  May  be  converted  to  use  upward  to  70  amps  at  any  time. 
.  .  .  Employs  the  largest  reflector  used  for  1-KW  service.  ...  By  far,  the 
greatest  dollar  value  in   lamps. 

The  New  Magnarc  De  Luxe  is  supreme  in  its  field  at  any  amperage,  between 
40  to  70.  .  .  .  Produces  10%  higher  screen  illumination.  .  .  .  The  highest 
ratio  of  screen  lumens  per  arc  watt.  ...  At  70  amperes,  with  a  projector  hav- 
ing an  efficient  DISC  type  revolving  shutter,  it  develops  t'ie  m-xmum  iig'it 
that  can  be  used  without  a  heat  filter.  .  .  .  Operating  costs  under  these  con- 
ditions, are  far  below  that  of  85  ampere  lamps.  .  .  . 

Magnarc  Lamps  assure  80%,  NOT  60%,  side-to-center  screen  light  distribu- 
tion. .  .  .  They  are  the  first  choice  and  preferred  lamp  of  large  or  small  Drive-Ins 
and  all  theatres. 


1  1 


FIRST    WITH    THE    FINEST 


t    t 


TRADE     MARK    REG. 


120-180  AMPERES 


This  modern  lamp  produces  all  the  light  there  is.  .  .  i 
It  is  the  standard  equipment  of  the  nation's  largest  and 
finest  theatres.  .  .  .  Used  by  90%  of  the  largest  Drive-In 
Theatres.  .  .  . 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  light  volume,  when 
used  with  projectors  that  have  efficient  DISC  type 
revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions. 


WHY    EXPERIMENT? 


Tj 


/  / 


J.E.McAULEY  MFG. CD. 


552-554    WEST   ADAMS    STREET 

CHICAGO  6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


11 


The  Use  of  Films  in  Television 


This  report,  prepared  by  the  Television  Committee  of  the  SMPE,  comprising  35 
specialists,  contributes  greatly  to  a  broad  understanding  of  the  art.  While  not  related 
directly  to  the  projection  process,  this  report  will  serve  to  lay  the  groundwork  for  a 
comprehensive  treatment  of  projection  equipment  and  technique  which  IP  will  publish 
shortly  in  line  with  its  policy  of  providing  inclusive  coverage  of  all  phases  of  television. 


AT  THE  present  time  films  for  Tv 
are  being  photographed  with  both 
35-  and  16-mm  motion  picture 
cameras  at  the  standard  speed  of  24 
frames  per  second.  For  production  work 
where  synchronized  sound  is  to  be  used, 
the  camera  must  be  driven  at  synchro- 
nous speed.  A  number  of  Tv  stations 
currently  making  their  own  newsreels 
use  commercially  available  16-mm  pro- 
fessional cameras  and  associated  equip- 
ment. 

Data  supplied  by  one  Tv  station  indi- 
cated that  because  adjustment  of  picture 
size  in  home  receivers  varies  greatly,  all 
significant  action  and  subject  material  be 
kept  within  a  central  area  having  8%% 
top  and  bottom  margins  and  13%  side 
margins.  When  this  is  done,  a  large 
majority  of  commercial  receivers  will 
show  all-important  information. 

Closeup  scenes  give  most  pleasing  re- 
production because  viewing  screens  of 
home  receivers  are  small  and  the  field 
of  action  necessarily  is  limited.  Medium 
shots  are  generally  considered  the  out- 
side limit,  and  long  shots  rarely  add 
anything  of  value  to  the  film  program. 
Subject  matter  should  be  kept  as  large 
as  the  limits  and  action  of  the  scene 
being  televised  will  allow  without  ob- 
vious crowding  of  action  or  characters. 

Picture  Patterns,  Lighting 

Whenever  possible,  checkerboard  pat- 
terns with  many  abrupt  changes  of  con- 
trast should  be  employed,  as  these  numer- 
ous large  variations  in  print  density  will 
reduce  the  horizontal-smear  effect  that 
otherwise  would  be  caused  by  low-fre- 
quency defects  of  present  systems.  For 
the  same  reason,  large  uniform-colored 
or  relatively  dark  areas  and  delicate  or 
minute  patterns  are  to  be  studiously 
avoided,  particularly  in  the  lower  portion 
or  foreground  of  the  scene. 

The  limited  range  of  picture-tube 
brightness  requires  that  subject  contrast 
be  controlled  whenever  possible.  Usually 
is  it  not  necessary  to  resort  to  flat  light- 
ing in  order  to  hold  contrast  within  the 
brightness  range  of  the  Tv  system,  but 
even  lighting  is  essential  particularly 
over  large  picture  areas.  That  is,  large 
picture  areas  must  have  about  the  same 


average  illumination.  Wide  variations 
in  brightness  over  the  scene  will  other- 
wise have  to  be  compensated  for  by  ad- 
justment of  the  Tv  shading  controls. 

Adequate  foreground  lighting  is  quite 
essential,  since  the  electric-energy-decay- 
rate  characteristic  of  the  iconoscope 
mosaic  '  may  cause  picture  degradation 
in  the  form  of  insufficient  signal  response 
in  the  lower  portion  of  the  received  pic- 
ture. The  general  intensity  of  illumina- 
tion from  scene  to  scene  should  be  kept 
relatively  Constant  so  that  the  level  of 
the  Tv  signal  does  not  change  markedly 
and  for  this  reason  night  scenes  should 
be  avoided. 

Properties,  Titles,  Action 

For  psychological  reasons  long  fades 
should  not  be  used  because  they  interrupt 
program  continuity  and  the  audience 
may  think  from  the  long  blank  period 
that  something  is  wrong  with  the  re- 
ceiver. 

Clothing  and  accessories,  backgrounds, 
furniture,  and  other  "properties"  should 
have  definite  patterns  large  enough  to  be 
clearly  visible  on  the  screen  of  the  Tv 
receiver.  Again,  fine  or  delicate  detail 
with  minute  changes  in  contrast  should 
be  avoided. 

To  reproduce  clearly  on  small  home 


Stratovision  Tv  System  'Iced' 

Westinghouse  Electric  Corp.  will  put  its 
Stratovision  system  of  Tv  transmission  "on 
dry  ice,"  thus  leaving  the  field  to  the  coax- 
ial cable  and  microwave  relay  systems. 
Stratovision  is  the  much-publicized  method 
of  relaying  Tv  programs  via  high-flying  air- 
planes. Although.  Westinghouse  predicted  an 
eventual  use  for  Stratovision,  competent  ob- 
servers feel  that  the  other  two  systems  will 
fill  all  needs. 

Although  cable  transmission  for  a  long 
while  surpassed  any  other  means  of  Tv  trans- 
mission, recent  increase  in  the  rate  of  relay 
station  construction  is  narrowing  the  for- 
mer's edge.  Most  engineers  now  believe  that 
each  of  the  two  dominant  methods  has  its 
advantages,  dependent  primarily  upon  the 
type  of  terrain  over  which  the  signal  is 
transmitted.  Ultimately,  it  is  felt,  transmis- 
sion is  likely  to  be  equally  divided  between 
the  two. 


receivers,  the  lettering  of  titles  should 
be  large,  boldface  on  a  textured  back- 
ground, and  should  always  be  located 
within  the  dimensional  limits  previously 
mentioned. 

Action  within  scenes  should  be  con- 
tinuous. This,  however,  is  not  always 
possible,  so  where  inanimate  objects  are 
shown  for  any  period  of  time,  motion  of 
the  camera  by  zooming,  traveling,  change 
of  angle,  or  slow  panning  should  be 
substituted  to  accomplish  the  desired 
effect. 

In  the  present  state  of  the  art,  this 
type  of  change  sometimes  emphasizes  the 
geometrical  distortion  in  the  final  image. 
In  the  transition  from  one  scene  to  the 
next,  it  is  desirable  to  employ  lap  dis- 
solves, quick  fades,  or  instantaneous 
"cuts"  timed  to  keep  pace  with  the 
program. 

Film  Processing  Procedure 

Normal  exposure  and  development,  as 
employed  in  motion  picture  negative 
work,  should  be  used  for  pictures  to  be 
televised.  Negative  gamma  is  usually 
carried  between  0.65  and  0.70,  and  the 
scene  density  is  considered  normal  if  the 
negative  prints  in  the  middle  of  the 
printer  scale. 

Over  a  period  of  years  numerous 
closed-circuit  tests  have  been  run  in  an 
attempt  to  determine  optimum  print 
density  for  Tv.  These  tests,  although 
they  were  not  conclusive,  have  shown  that 
low-contrast  prints  (gamma  between  1.4 
and  1.6)  with  a  general  density  near 
normal,  reproduce  well.  When  the  con- 
trast was  carried  to  normal  (gamma  of 
2.20  to  2.50)  the  print  which  reproduced 
best  was  at  least  two  printer  points  light. 

All  of  these  tests  were  made  from  a 
negative  exposed  for  motion  picture  the- 
atre use.  More  recent  tests  have  shown 
that  prints  of  normal  gamma  and  per- 
haps 1  to  2  printer  points  light  reproduce 
best.  In  view  of  the  great  importance 
of  establishing  proper  film  specifications 
for  Tv,  this  subject  needs  further  investi- 
gating and  reporting. 

Most  16-mm  film  used  by  Tv  stations 
is  processed  by  reversal.  Current  35-mm 
practice  shows  that  a  negative  gamma  of 
0.70  and  a  print  gamma  of  1.50  produce 


12 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


u  resulting  picture  contrast  of  1.05.  while 
current  16-mm  reversal  technique  pro- 
duces a  print  gamma  between  1.00  and 
1.20,  which  has  proved  satisfactory  and 
is  recommended. 

A  limited  amount  of  16-mm  negative 
and  print  work  is  being  done.  Current 
practice  is  to  develop  the  negative  in 
fine-grain  negative  developer  and  print 
normally. 

Transfer  from  Film  to  Tv 

The  translation  of  motion  pictures  into 
Tv  signals  is  complicated  by  the  fact 
that  motion  picture  film  moves  at  the 
standard  rate  of  24  frames  per  second 
while  the  rate  of  the  Tv  signal  is  30 
frames    (60  fields)    per  second. 

A  simple  factor  can  be  applied  to  the 
different  frame  rates  which  satisfies  the 
peculiar  characteristics  of  the  two  sys- 
tems. Two  frames  of  motion  picture 
film  require  the  same  amount  of  time  as 
five  fields  (2%  frames)  in  Tv  scanning. 
This  relationship  is  presented  graphically 
in  Figs.  1A  and  IB,  which  show  that  if 
one  film  frame  is  scanned  for  two  Tv 
fields  and  the  next  film  frame  for  three 
Tv  fields,  the  time  difference  of  frame 
rate  can  be  satisfied. 

This  relationship  is  fundamental  as 
long  as  the  respective  frame  rates  are 
retained  and  applies  regardless  of  type 
of  camera  or  projector. 

There  are  two  fundamentally  different 
t\  pes  of  Tv  pickup  tubes,  the  storage  type 
(iconoscope — -image  orthicon)  which 
stores  electrical  charges  produced  by  a 
multitude  of  individual  picture  elements 
until  discharged  by  the  scanning  electron 
beam;  and  the  non-storage  type  (image 
dissector — phototube)  where  the  electri- 
cal energy  of  each  picture  element  is 
proportional  to  the  incident  light  experi- 
enced at  the  instant  that  element  is 
scanned.  The  phototube  is  used  with 
the  flying-spot  scanner  and  is  gaining  in 
popularity  with  development  engineers. 

Iconoscope  Tube  Technique 

The  iconoscope  camera  tube,  however, 
is  almost  universally  used  for  commer- 
cial-film pickup  work.  Because  of  its 
storage  feature  the  iconoscope  can  be 
'"pulsed"  with  an  intense  burst  of  light 
of  short  duration.  This  produces  a 
charge  picture  in  the  tube  that  is  then 
removed  in  the  normal  scanning  se- 
quence. 

This  flash  may  not  be  applied  during 
the  actual  scanning  time  since  it  would 
give  a  pulsed  video  signal  and  a  notice- 
able black  "application  bar"  across  the 
receiver  screen.  Light  is  therefore  ap- 
plied during  the  vertical-blanking  period, 
and  its  pulse  effect  is  further  nullified 
by  proper  back  lighting  of  the  mosaic 
screen  in  the  iconoscope  tube  and  elec- 
tronic gating  of  the  beam  current.  Since 
light  is  applied  only  during  vertical 
blanking  a  full  scanning  interval  is  avail- 


able for  pulldown  of  the  next  film  frame. 
Figure  1C  indicates  the  sequence  of 
charging  the  camera  tube  with  a  light 
pulse,  scanning  the  resulting  picture,  and 
film  pulldown  in  35-mm  projectors. 
Either  mechanical  or  electrical  means 
can  provide  the  pulse. 

Precise  Control  Necessary 

A  pulldown  of  approximately  50  de- 
grees and  a  mechanical  shutter  having 
an  opening  of  less  than  18  degrees  and 
synchronized  at  3600  r.p.m.  to  open 
during  the  Tv  vertical-blanking  pulse 
time  is  practical  for  16-mm  projectors. 
Equipment  is  also  available  with  an 
electrically  timed  and  controlled  gas- 
discharge  tube  instead  of  a  mechanical 
shutter. 


Control  of  the  iconoscope  camera  re- 
quires adjustment  of  the  beam  current 
and  continual  monitoring  of  picture 
"shading."  Beam  current  can  be  set  for 
average  light  level,  compromising  be- 
tween excessive  tube  noise  at  high  beam 
levels  and  low  signal  with  resulting 
amplifier  noise  at  high  beam  levels. 

Shading,  an  undesirable  characteristic, 
is  a  spurious  signal  resulting  from  an 
uneven  distribution  of  secondary  elec- 
trons on  the  tube  mosaic  and  varies  with 
picture  content.  Adequate  correction  can 
be  obtained  by  properly  mixing  artifi- 
cially generated  signals,  saw-tooth  and 
parabolic,  and  occasionally  some  sine- 
wave  forms  in  both  the  vertical-  and  hori- 


FIGURE  1 


-FILM    FRAME    NO.  I  — 
l/24  SEC  =0.0417  SEC 


FLICKER 
SHUTTER 


0.0083    ]•*-  0.0125— *\  0.008J    [*—  0.01; 


-FILM    FRAME    NO. 2- 


FLICKER 
SHUTTER 


A. — 35-mm  motion  picture  projector  with  72-degree  shutter,  24  frames 

per  second. 


-TELEVISION    FRAME   NO.  I- 
l/30  SEC  =  0.0333  SEC 


■  EVEN   FIELD 
1/60"  0.0166 


ODD  FIFLD- 
1/60  =  0.0166 


-TELEVISION  FRAME   NO.  2  • 


l« O.OISB *M  |J  I  I 

^•VERTICAL  BLANKING   ^3  SEC  =0.00083  SEC  . 

B. — Television  picture  with  interlace  scanning,  30  frames  per  second. 


-0.0158 

^VERTICAL  BLANKING  =0.00083SEC 
-TELEVISION    FRAME    NO.  I 


£: — 35-mm  television  intermittent  storage  system  of  scanning  motion 

picture  film. 


'/2 

-FILM    FRAME   NO.  I ►+•< FILM    FRAME    NO.  2 »+«—  FILM  FRAME -»■ 

'/30  SEC  j  '/so  SEC  NO- 3 


-THIS  PORTION  OF  TELEVISION    FRAME  MUST  BE 
BLANKED    BECAUSE    FILM    IS    IN    MOTION 


-TELEVISION    FRAME    NO. 
0.0358 


-TELEVISION    FRAME    NO.  2  - 
0.0358 


BLANKING  TIME  = 


18.4  PERCENT 


NOTE:     ALL    DIMENSIONS    ARE    IN 
PARTS   OF  A  SECOND 


D. — Television  scanning  of  motion  picture  film  run  at  30  frames  per 
second,  72-degrees  pulldown  time. 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


13 


-1/12  SEC- 


•  1/24  SEC- 


■1/30  SEC.- 


[•—  \/%0: 


FRAME   I 


-FRAME  2- 


SHUTTES  OPEN 


PULL   | 
DOWN  U- 
PERIOD 


SHUTTER 
CLOSED 


SHUTTER  OPEN 


I  PERIOD 
J , 


SHUTTER 
CLOSED 


FIGURE  2 

Time  sequence   of   exposure   and  pulldown   timing   of  the   camera    in 
relation  to  the  field  rate  of  the  television  image. 


zontal-scanning  directions,  and  applying 
the  results  to  the  camera  output. 

Another  difficulty  known  as  edge  flare, 
which  shows  up  as  bright  areas  usually 
on  the  right  edge  and  bottom  of  the  pic- 
ture, can  be  improved  by  the  adjustment 
of  an  internal  edge  lighter. 

With  proper  adjustment  of  the  controls 
and  proper  high-light  illumination  of  the 
iconoscope  mosaic  a  very  satisfactory 
picture  is  obtained.  Resolution  usually 
exceeds  350  Tv  lines  and  the  signal-to- 
noise  ratio  is  low  but  tone  gradation 
is  not  perfectly  linear.  The  signal-out- 
put current  is  approximately  proportional 
to  brightness  of  mosaic  illumination  up 
to  about  0.1  foot-candle,  but  at  brighter 
levels  the  signal  increases  less  rapidly 
with  increasing  brightness.  Thus,  in 
combination  with  the  normal  viewing 
tube  both  the  blacks  and  the  whites  seem 
to  be  compressed. 

The  coating  on  the  mosaic  of  the  Type 
1850-A  iconoscope  shows  a  preference 
for  the  blue  region  of  the  spectrum  so 
that  color  films  can  be  projected  for 
black-and-white  Tv  pickup,  but  tone 
values  of  various  colors  will  not  agree 
perfectly  with  those  seen  by  the  eye. 
Some  partial  correction  is  possible  by 
the  use  of  filters  on  the  light  source. 

Flying-Spot  Scanner  Promising 

The  phototube  flying-spot  scanner  sys- 
tem is  now  undergoing  development  and 
shows  considerable  promise.  It  has  a 
number  of  very  desirable  advantages  over 
the  iconoscope  for  film  pickup,  namely, 
simplicity  of  components,  freedom  from 
shading  and  other  spurious  signals,  no 
loss  of  stored  charge  during  the  scanning 
cycle,  excellent  contrast  range,  and  high 
picture  resolution. 

A  major  difficulty  of  the  flying-spot 
scanner,  as  in  any  type  of  non-storage 
Tv  camera  tube,  as  shown  by  Fig.  IB, 
is  that  no  film  pulldown  time  is  available 
when  the  projector  is  run  at  30  frames 
per  second.     Some  type  of  nonintermit- 


tent  projector  would  seem  to  be  desir- 
able, but  the  complexity  as  well  as  un- 
satisfactory speed  regulation  of  several 
proposed  types  of  continuous  projectors 
presents  a  serious  problem. 

The  iconoscope  camera  and  the  flying- 
spot  scanner  are  both  useful  with  still 
slides  or  filmstrips  in  a  standard  projec- 
tor. Camera  switching  can  be  accom- 
plished by  remote  control,  and  in  one 
case,  two  film  projectors  and  a  slide 
projector  can  be  switched  into  a  single 
camera  by  the  use  of  an  accessory  optical- 
mirror  device. 

Tv  lends  itself  nicely  to  "fades,"  "dis- 
solves," and  superposition  of  two  pictures 
by  the  simple  expedient  of  mixing  video 
signals  at  the  required  level  before  add- 
ing the  standard  synchronizing  signal. 
Necessary  controls  are  commercially 
available  as  standard  studio  equipment. 
"Wipes"  are  somewhat  more  difficult,  re- 
quiring an  electronic  switch  of  a  type 
that  is  not  as  yet  commercially  available. 

Sound  for  Tv  from  film  sources  re- 
quires no  special  handling  beyond  equal- 
ization. 

Film  from  Tv  Sources 
(Cathode-Ray  Photography) 

Motion  pictures  photographed  from  a 
Tv  picture  tube  are  made  as  transcrip- 
tions of  live-studio  or  remote  programs 
for  rebroadcasting  and  may  be  used  at  a 
later  time  by  the  station  that  presented 
the  original  program  or  may  be  syndi- 
cated with  several  prints  from  the  origi- 
nal made  for  distribution  to  subscriber 


stations.  Picture-  and  sound-quality  re- 
quirements are  high,  demanding  utmost 
attention  on  the  part  of  station  and  pro- 
cessing laboratory  personnel. 

Regular  record  films  are  also  made  but 
generally  at  a  reduced  film-frame  rate 
and  have  far  less  rigid  quality  require- 
ments because  they  are  never  rebroad- 
cast. 

Frame-per-Second  Conversion 

The  conversion  from  the  30-frame-per- 
second  Tv  picture  rate  to  the  24-frame- 
per-second  film-picture  rate  presents  a 
serious  problem  for  Tv  recording-camera 
design  engineers.  A  currently  successful 
solution  is  based  on  the  use  of  successive 
dissimilar  scanning  cycles. 

Another  proposed  answer  is  a  change 
of  the  standard  film  rate  from  24  to  30 
frames  per  second.  The  logic  of  this 
solution  appears  obvious,  but  there  is  a 
serious  handicap  of  economic  inertia  to 
consider  since  sound  films  have  been 
made  at  24  frames  per  second  and  studios 
and  theatres  have  been  following  the 
present  standard  for  over  20  years.  There 
is  also  the  problem  of  providing  pull- 
down time  if  photography  is  on  an  inter- 
mittent basis. 

If  a  film  rate  of  30  frames  per  second 
is  ever  adopted,  it  appears  that  some 
method  of  continuous  film  motion  will  be 
desirable,  if  the  necessary  constancy  of 
motion  can  be  obtained. 

It  is  possible  to  design  cameras  that 
use  either  mechanical  or  electrical  blank- 
ing during  the  pulldown  period.  Con- 
tinuously moving  film  cameras  are  also 
possible,  but  the  mechanical,  optical,  and 
synchronization  problems  involved  are 
most  difficult. 

Modern  16-mm  Recording  Camera 

One  16-mm  Tv  recording  camera  now 
in  use  is  equipped  with  a  mechanical 
shutter  driven  by  a  synchronous  motor 
from  the  same  60-cycle  a-c  power  source 
as  is  used  for  the  Tv  synchronizing  gen- 
erator. This  shutter  has  a  closed  angle 
of  72  degrees  and  an  open  angle  of  288 
degrees.  At  the  24-cycle  rate  this  repre- 
sents a  closed  time  of  1/200  second  and 
an  open  time  of  1/30  second.  The  latter 
is  equivalent  to  one  full  Tv  frame  cycle. 

Figure  2  shows  the  time  sequence  of 
this  shutter  in  relation  to  the  30-frame 
(60-field)  Tv  scanning  cycle.  The  cam- 
(Continued  on  page  31) 


PROJECTION   EQUIPMENT  EXPORT  FIGURES  OVER  TWO-YEAR  PERIOD 
Film  Project-ion  Equipment     Number — 1948 — Value        Number — 1947 — Value 


35-mm  Projectors 

4,154 

$1,637,679 

6,936 

$2,532,173 

16-mm  Silent  Projectors 

4,830 

543,753 

8,528 

665,764 

16-mm  Sound  Projectors 

8,440 

2,357,505 

10,065 

2,961,932 

8-mm  Projectors 

9,278 

636,362 

14,172 

741,242 

Arc  Lamps 

1,887 

419,233 

3,485 

701,859 

14 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


Precise  Calibration  of  Lens  Markings 


IN  THE  course  of  an  experimental  study 
of  errors  in  the  speed  markings  of 
photographic  lenses,  Dr.  F.  E.  Washer 
of  the  National  Bureau  of  Standards  has 
devised  a  convenient  graphic  method  for 
converting  each  of  these  markings  for  a 
given  lens  to  the  corresponding  "effective 
F-number" — an  F-number  corrected  for 
light  losses  within  the  lens. 

In  this  way  it  is  possible  to  calibrate 
a  lens  so  that  "losses  of  light  from  absorp- 
tion, reflection,  and  scattering  within  the 
lens  are  taken  into  account,  and  a  more 
accurate  control  of  the  amount  of  light 
admitted  to  the  exposed  film  is  obtained. 

In  recent  years,  photographic  technol- 
ogy has  largely  developed  from  an  em- 
pirical art  to  an  exact  science,  making  it 
possible  to  control  results  in  a  more  sci- 
entific manner.  With  this  progress,  a 
demand  has  arisen  for  greater  precision 
in   the    speed    marking    of   lenses.     The 


V 

to 

\ 

\\ 

. 

\ 

\ 

H 

\  V 

s  \ 

s 

\ 

\ 

\ 

\ 

z 
o 

\ 

\\ 

\  ' 

S    ■ 

\ 

\ 

\ 

\ 

o 

,     \ 

s  « 

I 

' \ i 

\ 

V 

z 

! 

\ 

i 

\ 

F- NUMBER 

FIGURE  1 

method  now  in  general  use  is  based  en- 
tirely on  the  ratio  of  the  equivalent  focal 
length  of  the  lens  to  the  diameter  of  the 
aperture.  This  ratio — known  as  the  F- 
number — gives  no  consideration  to  the 
great  differences  in  the  useful  light  trans- 
mitted by  various  lenses. 

New  Marking  Methods  Proposed 

To  correct  the  situation,  several  new 
methods  of  marking  lens  diaphragms 
have  been  proposed  which  give  weight  to 
the  variations  in  the  loss  of  light  for  dif- 
ferent lenses.  Not  long  ago,  Dr.  I.  C. 
Gardner  of  the  National  Bureau  of  Stand- 
ards developed  a  method  of  testing  the 
marked  diaphragm  openings  so  that  val- 
ues which  entirely  compensate  for  differ- 
ences in  transmission  can  be  obtained 
and  applied  to  the  scale  of  F-numbers  on 
a  photographic  lens. 

In  this  system  the  markings,  known  as 
effective  F-numbers  or  T -numbers,  are 
obtained  by  means  of  a  photoelectric 
cell  and  a  relatively  simple  photometric 
procedure,  in  which  the  diaphragm  of 
the  lens  to  be  calibrated  is  adjusted  to 


transmit  the  same  amount  of  light  as  a 
similarly  placed  opening  of  standard 
size.  The  standard  opening  corresponds 
to  an  ideal  lens  of  a  given  aperture  ratio, 
in  which  incident  light  is  wholly  trans- 
mitted. A  complete  calibration  is  ob- 
tained by  the  use  of  a  series  of  openings 
of  graduated  size  corresponding  to  vari- 
ous aperture  ratio  values. 

More  recently,  this  work  has  been  ex- 
tended by  Dr.  Washer  in  a  study  of  the 
errors  in  the  marking  of  20  lenses  hav- 
ing focal  lengths  between  0.5  and  47.5 
inches.  It  was  found  that  the  effective 
F-number  of  the  ideal  lens  can  be  read- 


ily determined  for  each  of  the  marked 
stop  openings  if  the  light  meter  readings 
for  a  series  of  standard  diaphragms 
(placed  between  the  meter  and  a  light 
source)  are  compared  graphically  with 
the  meter  readings  for  the  range  of  dia- 
phragm openings  of  the  lens  (Fig.  1). 

Establishing  the  Graph  Data 

Two  curves  of  about  the  same  slope 
are  obtained  by  plotting  the  scale  deflec- 
tions of  the  light  meter  against  (1)  the 
effective  F-numbers  or  F-numebrs  corre- 
sponding to  the  standard  diaphragms 
and  (2 )  the  marked  F-numbers  of  the 
lens.  The  first  curve  will  be  a  straight 
line,  since  the  plotted  F-numbers  of  the 
(Continued  on  page  30) 


Notes  Anent  the  Simplex  E-7  Double-Film  Attachment 


Frequent  reference  in  the  literature  to 
the  double-film  projector  attachment 
used  in  the  studios  and  elsewhere 
prompts  publication  here  of  these  ex- 
planatory notes  and  a  graphical  expo- 
sition, in  both  halftone  and  line,  of  the 
film  path  through  the  mechanism. 

The  double-film  attachment  provides 
for  the  running  of  separate  picture  and 
sound  prints.  The  film  containing  the 
picture  starts  in  the  upper  magazine, 
runs  through  the  projector  mechanism 
and  a  film  channel  (which  forms  a  part 
of  the  double-film  attachment)  into  the 
lower  magazine.  The  film  containing  the 
sound  track,  on  the  other  hand,  starts  in 
the  lower  magazine,  runs  through  the 
film  channel  and  sound  mechanism  and 
returns  into  the  lower  magazine. 

The  magazine  and  film  channel  as- 
sembly consists  of  a  lower  magazine  for 
three  1000-foot  reels  (when  two  films 
are  used) ,  a  takeup  reel  for  the  picture 
film,  and  a  feed  and  takeup  reel  for  the 


sound  film.  The  film  channel,  which  is 
attached  to  the  motor  bracket  after  cer- 
tain modifications  of  the  projector  are 
made,  provides  an  enclosure  for  the  pic- 
ture film  between  the  projector  mechan- 
ism and  the  lower  magazine,  and  also 
for  the  sound  film  between  the  lower 
magazine  and  the  sound  mechanism.  A 
sound  sprocket  and  film  guide  rollers 
are  included. 

Space  is  provided  in  the  lower  maga- 
zine so  that  2000-foot  reels  may  be 
utilized  when  a  combined  picture  and 
soundfilm  is  used. 

The  modification  of  the  projector 
mechanism  and  the  actual  installation 
of  the  entire  unit  require  a  thoroughgo- 
ing knowledge  of  the  equipment  and  ex- 
treme care  in  procedure.  The  entire 
process  is  described  in  great  detail  in 
a  special  six-page  illustrated  folder 
issued  by  International  Projector  Corp. 
(Bloomfield,  N.  J.) ,  since  the  equipment 
shown  and  referred  to  herein  is  a  modi- 
fied Simplex  E-7  projector. 


Photo   by   Metro-Goldwyn-Mayer   studio. 


A  -  Picture  film 
B  -  Sound  film 


If  one  film  (picture 
end  sound)  la  run,  use 
this  take-up  reel  and 
thread  per  Instruction 
"SH-1000  sound  Mech- 
anism." Rotate  roller 
"c"  to  right  to  c: 
2000-foot  reel. 


Graphical  representation  in  both  line  and  halftone  of  the  Simplex  double-film  attachment  (sepa- 
rate visual  and  sound  films)  with  special  emphasis  upon  method  of  threading.   This  equipment  is 
used  extensively  in  studio  work  and  elsewhere  where  special  processes  are  employed. 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


15 


PORTENDING  a  drastic  shift  in  em- 
phasis of  approach  to  technological 
problems  by  motion  picture  engi- 
neers from  the  optico-mechanical  to  the 
purely  electronic,  and  presaging  impor- 
tant changes  in  operation  and  economics 
in  the  theatre  field,  were  the  happenings 
at  the  65th  Convention  of  the  Society  of 
Motion  Picture  Engineers  at  the  Hotel 
Statler,  April  4-8.  Registration  ap- 
proached the  700  mark. 

If  the  printed  program  of  the  Conven- 
tion didn't  tip-off  the  metamorphosis  of 
thought  and  action  which  the  industry's 
engineering  forces  are  now  undergoing, 
SMPE  officers  themselves  made  it  crys- 
tal-clear by  boldly  announcing  and  vig- 
orously supporting  a  suggested  change 
in  name  of  the  organization  to  Society  of 
Motion  Picture  and  Television  Engineers 
(italics  ours).  That  the  change  will  be 
effected  is  a  foregone  conclusion. 

The  character  of  the  Convention  was 
made  immediately  apparent  when  the 
speakers  at  the  get-together  luncheon 
discussed  Tv,  more  Tv — and  nothing  else. 
Followed  then  two  days  given  over  in 
their  entirety  to  Tv  in  the  form  of  papers, 
demonstrations  and  open  forums. 

Exhibitor-Engineer  Tieup 

One  happy  circumstance  of  the  pro- 
ceedings was  the  announcement  of  the 
affiliation  with  the  Society  as  a  sustaining 
member  of  the  Theatre  Owners  of  Amer- 
ica, and  this  progressive  step  by  the  ex- 
hibitors was  followed  up  by  a  joint  meet- 
ing for  the  first  time  in  history  of  the 
Tv  committees  of  both  organizations. 
Other  similar  meetings  are  scheduled  for 
the  near  future,  and  there  is  every  indi- 
cation that  exhibitors  are  at  last  aroused 
to  the  threat  to  their  security  posed  by 
the  phenominal  growth  of  Tv. 

Dr.  Allen  B.  DuMont,  opining  that 
present  Tv  films  were  too  poor  in  quality 
and  too  costly  to  make  them  "preferred" 
entertainment  for  theatre  Tv  program- 
ming, predicted  that  the  time  will  come 
(he  didn't  say  when)  when  there  will  be 
Tv  systems  capable  of  matching  the  best 
reproduction  standards  of  35-mm  film. 
Other  DuMont  observations: 

"Live"  programs  are  today  less  costly 
than  films  for  Tv  network  purposes. 
Within  a  year  there  would  be  no  discern- 
ible difference  in  quality  of  images  as 
between  direct  coaxial  transmission  and 
Tv-transcription.  Present  costs  of  cable 
transmission  and  the  use  of  film  are  al- 
most identical.  Some  top  present  Tv 
programs  might  be  piped  into  theatres 
pending  the  wider  distribution  of  home 
Tv  sets. 

Also,  color  Tv  still  is  10  or  15  years 
away,  although  quite  some  progress  has 
been  made  in  this  field.  At  present  about 
50%  of  the  total  population  of  the  U.  S. 
live   in  an   area   of  Tv   reception,   which 


figure  will  mushroom  with  the  expected 
opening  of  from  40  to  50  additional  Tv 
stations  this  year. 

Highlight  of  the  Tv  sessions  was  the 
demonstration  by  RCA  of  its  improved 


SMPE 

Convention 

Roundup 


direct  instantaneous  -  projection  theatre 
Tv  system.  The  system  will  be  available, 
in  pilot-run  quantities,  probably  by  the 
end  of  this  year.  The  price  for  a  single 
unit  without  standby  facilities  is  ex- 
pected to  be  $25,000. 

RCA  Direct-Projector  Tv 

Indicating  the  solution  of  such  prob- 
lems as  length  of  throw  and  proper  loca- 
tion in  the  theatre,  this  RCA  equipment 
now  utilizes  a  20-inch  mirror  and  a 
LS^-inch  molded  plastic  lens  having  a 
combined  weight  of  only  50  pounds,  as 
contrasted  with  the  500-pounds  weight 
of  the  optical  system  used  little  more 
than  six  months  ago.  A  smaller  optical 
barrel,  only  30  inches  in  diameter  and 
36  inches  long,  is  now  the  only  element 
of  equipment  required  in  the  theatre 
auditorium,  and  for  a  15  ,x  20-foot  screen 
image  this  barrel  may  be  mounted  from 
40  to  65  feet  from  the  screen.  The  maxi- 
mum throw  of  earlier  equipments  was 
40  feet. 

For  the  SMPE  demonstration,  the  op- 
tical barrel  was  mounted  on  a  7-foot-high 
pipe  standard.  An  optical  barrel  of 
this  type  might,  however,  be  mounted  in 
the  front  of  a  theatre  balcony,  providing 
the  throw  would  not  exceed  65  feet; 
and  it  was  indicated  that  methods  may 
be  worked  out  for  suspending  such  a 
system  from  the  theatre  ceiling,  if  such 
an  arrangement  should  be  found  de- 
sirable. 

In    the    laboratory    model    shown,    a 


small  picture  amplifier  was  attached  to 
the  side  of  the  optical  barrel.  The  hori- 
zontal and  vertical  deflection  amplifiers 
and  synchronization  circuits  were  housed 
in  a  cabinet  which  can  be  located  up  to 
50  feet  away  from  the  optical  system.  A 
second  cabinet  houses  the  high-voltage 
supply,  and  a  third  is  used  for  the  plate 
power  supply  and  control  console. 

Both  of  the  latter  may  be  located  from 
2  to  300  feet  away  from  the  optical  bar- 
rel, if  desired,  making  it  possible  to  con- 
trol the  system  entirely  from  the  regular 
projection  room  in  a  theatre. 

Possible  Tv  Program  Sources 

Theatre  Tv  programming  appears  to 
fall  into  two  broad  classes,  in  RCA's 
opinion,  as  follows: 

1.  Regular  Tv  broadcast  material. 

2.  So-called  "closed-circuit"  perform- 
ances in  which  a  privately-originated 
program  is  fed  to  one  or  more  thea- 
tres. 

In  the  second  case,  some  examples  of 
originating  sources  might  be: 

A.  "Live"  action  in  a  studio  from  the 
stage  of  a  theatre  or  from  some  pub- 

-   lie  place  such  as  a  sports  arena  or  a 
site  of  a  political  event. 

B.  Motion  picture  film  produced  either 
in  more  or  less  regular  fashion,  or  by 
Kinescope  photography  to  "store" 
some  program  such  as  those  de- 
scribed. 

In  any  case,  program  transmission 
might  be  by  microwave  relay,  equalized 
telephone  lines,  coaxial  cable,  or  some 
combination  of  these. 

The  pictures  shown  by  RCA  included 
regular  program  material  picked  up 
from  Tv  station  WNBT,  part  by  radio 
transmission  and  part  by  equalized  tele- 
phone line;  live  action  picked  up  by  an 
image-orthicon  camera  located  in  an  ad- 
joining room;  and  motion  pictures 
scanned  by  equipment  also  located  in 
the  anteroom.  Image  quality  was  far 
removed  from  that  of  good  35-mm  thea- 
tre projection,  as  might  be  expected  at 
this  stage  of  development  of  Tv,  although 
there  was  a  noticeable  improvement  in 
the  quantity  of  projected  light. 

Tv  as  a  Box-Office  Aid? 

Other  observations  anent  Tv:  Ralph 
Austrian,  formerly  with  RCA  and  RKO 
and  now  a  Tv  consultant,  said  that  thea- 
tre Tv  is  destined  to  become  the  most 
potent  force  in  halting  any  drop  in  film 

Eddie  Auger  Stricken  at  SMPE  Meet 

A  tragic  note  was  sounded  at  the  SMPE 
Convention  when  Edward  Auger,  67,  who 
retired  several  years  ago  as  a  national  RCA 
representative  in  the  theatre  field,  died  sud- 
denly in  the  lobby  of  the  Hotel  Statler, 
Known  to  thousands  of  exhibitors  and  pro- 
jectionists, Auger  was  attending  the  Conven- 
tion in  a  private  capacity. 


16 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


grosses.  Large  screen  Tv,  he  said,  will 
soon  become  the  greatest  tool  of  all  to 
get  people  out  of  their  homes  into  thea- 
tres. The  fact  that  the  exhibitor  has  a 
box-office  makes  him  the  sole  person  with 
an  answer  to  the  question  of  who  is 
going  to  pay  for  Tv,  said  Austrian,  add- 
ing that  the  motion  picture  industry  can- 
not preserve  its  prosperity  by  doing 
nothing  to  counteract  the  advance  of  Tv. 

Phonevision.  a  Tv  system  intended  to 
be  tied  in  with  'phone  lines  and  require 
payment  for  program  reception  in  the 
home,  was  pictured  by  a  Zenith  Radio 
representative  as  freeing  Tv  from  com- 
mercialism and  providing  Hollywood 
with  a  steady  income.  Strictly  a  home- 
Tv  proposition.  Phonevision  is  not  seri- 
ously regarded  as  practicable  by  film 
people. 

The  third  Convention  day  was  given 
over  to  a  symposium  on  high-speed  pho- 
tography, of  little  interest  to  readers  of 
IP.  except  for  mention  that  one  of  the 
subjects  discussed  was  the  taking  of  mo- 
tion pictures  at  speeds  up  to  500,000 
exposures  per  second,  while  in  the  still 
picture  field  there  exists  a  method  for 
taking  pictures  at  an  exposure  time  of 
about  1/20-milbonth  of  a  second! 

Philips    Lamp   Works,    of    Eindhoven, 


Holland,  presented  a  paper  on  a  mercury- 
vapor  lamp  which  operates  on  d-c  and 
lights  an  area  5  inches  in  diameter  to  a 
value  of  50,000  foot-candles. 

16-mm  Group  Goes  to  Town 

The  16-mm  proponents  took  over  the 
proceedings  on  the  fourth  day,  and  they 
proceeded  to  sponsor  a  session  which  by 
means  of  papers,  an  open  forum  in  which 
no  punches  were  pulled,  and  the  exhibi- 
tion of  16-mm  films  which  visually  and 
aurally  were  eye-openers  and  served  no- 
tice on  the  35-mm  contingent  that  the 
smaller-guage  film  was  now  ready  to 
make  a  real  fight  for  preeminent  posi- 
tion in  the  industry. 

It  was  generally  conceded  that  the 
days  when  16-mm  sound  recording  and 
reproduction  was  bound  by  the  limita- 
tion of  a  4000-cycle  top  cutoff  were  defi- 
nitely past.  During  this  session  were 
presented  some  examples  of  magnetic 
tape  recording  and  reproduction  which 
made  one  wonder  if  this  medium  would 
not  some  day  not  too  distant  in  the  future 
give  sound-film  a  terrific  fight  for  its  life. 

The  closing  day  saw  the  presentation 
of  a  paper  by  E.  K.  Kaprelian,  of  the 
U.  S.  Signal  Corps,  which  covered  the 
theory  of  design  of  large-aperture  objec- 
tive lenses  of  F  :1  or  greater.    The  author 


Letter  to  the  Editor — on  the  Square 

I  sincerely  hope  that  abstracts  of  the  more  interesting  of  the  forthcoming 
SMPE  papers  will  appear  in  IP.  It  does  seem,  though,  that  there  are  plenty 
of  really  practical  problems  requiring  attention,  and  that  excursions  into 
the  abstruse  technological  fringes  of  the  projection  field  are  out  of  place 
until  the  more  pressing  practical  problems  are  taken  care  of.  I  suppose 
everything  from  tape  recording  to  the  relativity-shift  of  light  rays  will  be 
discussed — everything,  that  is,  except  how  to  put  on  better  shows! 

Well,  if  most  projectionists  think  that  the  matter  of  rounded  screen 
corners  is  unimportant,  there  is  little  or  nothing  I  can  say  that  will  convert 
them  to  my  point  of  view.  I  really  am  a  fanatic  on  the  subject,  and  I  sup- 
pose that  I  am  the  only  member  of  the  True  Church  of  Screen  Masking. 

Come  to  think  of  it,  I  can  quote  something  from  the  "Bible"  to  you — 
the  "Bible"  being  IP.  On  pp.  27  of  the  March  issue  there  is  a  little  item 
titled  "Slant  Lines  Held  Less  Visible".  That  is  just  the  clue  I  have  been 
waiting  for!  Now  I  can  begin  to  understand  why  the  rounded  corners  are 
less  conspicuously  visible  (pschologically)  than  the  sharp,  square  ones. 
The  angle  which  the  middle  of  the  curve  makes  is  45°  to  the  horizontal  and 
vertical  boundaries  of  the  screen  image! 

More  power  to  those  Kodak  scientists :  they  are  doing  my  work  for  me. 
I  don't  care  a  whit  that  most  exhibitors  use  square  screen  corners  at  the 
present  time:  they  have  clearly  fallen  into  damnable  error.  Perhaps  some 
day  they  will  see  the  light — and  not  on  the  square. 

Frankly,  though,  I  am  100%  serious  about  this  matter  of  screen  corners. 
Rounded  corners  really  help  to  relax  the  audience  and  keep  them  absorbed 
in  the  picture.  Non-dramatic  films  don't  need  rounded  corners;  but  with 
the  exception  of  newsreels,  travelogues,  and  documentaries,  all  the  films 
made  for  theatre  exhibition  depend  upon  tangible  emotional  qualities.  Most 
of  it  is  hokum,  but  that's  the  way  it  should  be.  Corn  means  shekels  at  the 
box-office. 

I  am  one  of  those  old-fashioned  souls  who  believe  that  highbrow,  intel- 
lectual films  having  "significance"  can  kill  the  picture  industry  quicker  than 
can  television.  People  go  to  the  movies  to  laugh  and  cry  and  be  thrilled — 
not  to  think! — Robert  A.  Mitchell. 


summarized  the  application,  testing  and 
performance  of  these  extreme  aperture 
objectives. 

F.  J.  Kolb,  of  Eastman  Kodak  Co., 
pointed  out  that  experiments  had  shown 
that  air-cooling  of  motion  picture  film 
would  minimize  the  in-and-out-of-focus 
effect  which  occurs  as  the  film  passes 
through  the  heat  at  the  aperture.  He 
said  that  30  to  60%  additional  screen  il- 
lumination can  be  obatined  if  film  is  air- 
cooled  and  its  position  controlled  by 
high-velocity  air  jets  at  the  aperture. 

Electronic  Arc;  L-S  Cell 

A  new  method  of  controlling  the  feed- 
ing of  carbon  arcs  was  described  by 
J.  K.  Elderkin  of  the  Forest  Manufac- 
turing Corp.  In  this  method  (already 
described  in  IP)  each  feeding  mecha- 
nism is  individually  driven,  and  the  num- 
ber of  feeding  impulses  may  be  varied 
from  20  to  120  per  minute.  R.  W.  Lee, 
of  General  Precision  Labs,  offered  a 
paper  on  "Lead-Sulphide  Photocell 
Characteristics  for  Use  With  Film  Sound 
Tracks."  This  cell  (also  discussed  in 
past  issues  of  IP)  is  generally  regarded 
as  having  many  advantages  over  the  con- 
ventional caesium  cells  now  in  use. 

Abstracts  of  many  of  the  papers  pre- 
sented at  the  Convention  are  appended 
hereto: 

AIR  COOLING  MOTION  PICTURE  FILM  FOR 

HIGHER  SCREEN  ILLUMINATION 

F.  J.  Kolb 

Eastman  Kodak  Company 

One  of  the  limiting  factors  in  obtaining 
the  maximum  obtainable  screen  illumination 
in  motion  picture  projection  is  the  film 
itself,  which  does  not  perform  satisfactorily 
beyond  a  certain  maximum  intensity  of 
radiation.  Such  limitations  are  particularly 
serious  when  an  unusually  large  screen  is 
needed,  as  in  a  drive-in  theatre. 

Studies  made  of  film  behavior  under  high 
projection  intensities  have  shown  that  heat- 
ing of  the  film  is  apt  to  swell  it  out  of  focus. 
One  method  of  overcoming  this  problem  is 
increasing  the  cooling  of  the  film. 

A  method  has  been  devised  of  measuring 
radiant  energy  incident  on  the  film  and 
studies  have  been  made  of  the  absorption 
of  radiation,  both  visible  and  infra-red,  on 
films  of  varying  silver  densities.  When  film 
is  projected  at  high  intensities  two  phen- 
omena occur  which  make  it  impossible  to 
obtain  a  satisfactory  screen  image:  in-and- 
out  of  focus  and  blistering.  Other  phen- 
omena, such  as  negative  drift,  embossing, 
change  in  reflected  image  tone,  focus  drift 
and  image  flutter,  are  not  nearly  so  serious. 

Experiments  in  air-cooling  have  been  made 
in  which  air  jets  are  directed  at  the  film  in 
the  aperture.  In  addition  to  cooling,  these 
jets  are  used  to  minimize  mechanical  dis- 
placement of  film  by  contributing  to  the 
proper  positioning  of  the  film.  The  equip- 
ment used  in  these  experiments  is  described 
(Continued  on  page  27) 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


17 


IN  THE 


SPOTLIGHT 


A  DELEGATION  from  Hollywood, 
including  IA  President  Walsh  and 
Roy  Brewer,  IA  representative  on  the 
West  Coast,  was  received  by  President 
Truman  several  weeks  ago  and  discussed 
with  him  the  present  deplorable  condi- 
tions in  the  studios.  The  President  was 
shocked  by  Walsh's  report  that  aboui 
40%  of  the  studio's  technical  employes 
were  jobless,  and  since  Great  Britain's 
restrictions  on  American-made  movies 
were  hurting  the  industry,  he  promised 
to  take  the  matter  up  with  the  British 
foreign  secretary,  Ernest  Bevin,  who  was 
in  Washington  at  the  time. 

•  Fred  Parker,  secretary  and  business 
representative  for  Local  433,  Rock 
Island,  111.,  reports  the  signing  of  new 
2-year  contracts  with  the  Tri-States 
Theatres  and  the  Singer  Davenport 
Corp.,  providing  for  increases  of  7%% 
for  the  first  year  and  an  additional  5% 
the  second  year,  plus  vacations  with  pay. 
The  projectionists  working  in  the  two 
drive-in  theatres  in  the  Local's  jurisdic- 
tion receive  $115  per  week  on  a  39-hour 
work  week.  Negotiations  now  in  prog- 
ress with  the  independent  theatres  are 
expected  to  be  concluded  very  shortly. 
Assisting  Parker  in  the  negotiations  are 
Mark  M.  Maston  and  Edward  Short. 

•  In  commemoration  of  his  deep  interest 
in  civic  affairs,  the  city  of  Utica,  N.  Y. 
has  named  a  new  housing  project  in 
honor  of  the  late  Glenn  H.  Humphrey, 
former  business  agent  of  Utica  Local  337 
and  for  many  years  secretary  of  the  10th 
District. 

•  The  first  of  a  series  of  educational 
meetings  on  the  technical  aspects  of 
theatre  television  was  held  several  weeks 
ago  at  the  Loew-Poli  College  Theatre  in 
New  Haven,  Conn.,  under  the  sponsor- 
ship of  the  Connecticut  State  Association 
and  the  five  IA  Locals  in  New  Haven — 
Nos.  74,  273,  795,  B  B-41,  and  F  F-41. 
About  400  persons,  including  district  and 
theatre  managers,  stagehands,  projec- 
tionists, and  other  theatre  employes  at- 
tended the  meeting,  which  is  the  fore- 
runner of  a  series  of  such  meetings  to 
be  held  in  many  other  key  cities. 

C.    Y.    Kean,    engineer    at    the    RCA 
Laboratory,  Camden,  N.  J.,  discussed  the 


technical  aspects  of  theatre  television. 
Following  the  showing  of  National  Car- 
bon Company's  Technicolor  film,  "Car- 
bon Arc  Projection,"  technical  questions 
pertaining  to  the  subject  were  answered 
by  the  company's  representatives — A.  B. 
West,  Paul  Reis,  and  Neil  Croarkin. 

Other  speakers  included  Prof.  E.  W. 
Bakke,  director  of  the  Yale  Labor  and 
Management  Center;  Joseph  M.  Rourke, 
secretary-treasurer,  Connecticut  Federa- 
tion of  Labor;  and  William  Scanlan,  IA 
representative. 

Anthony  N.  Basilicato  was  chairman 
of  the  General  Educational  Committee 
for  Local  273.  Other  members  of  the 
Local  serving  on  the  board  were  Alfred 
Frazier,  president;  Louis  LaVorgna,  Jr., 
vice-president;  Ernest  De  Gross,  secre- 
tary; Edwin  Boppert,  treasurer;  and 
Matthew  Kennedy,  business  representa- 
tive. 

•  Clarence  Jalas,  secretary  of  Chicago 
Local  110,  was  appointed  by  Mayor  Ken- 
nelly  of  Chicago  to  the  board  of  exami- 
ners for  motion  picture  projectionists. 

•  A  gala  affair  was  the  Silver  Anniver- 
sary celebration  last  months  by  Local 
631,  Orlando,  Fla.  The  festivities  began 
at  3  o'clock  in  the  afternoon  with  open 
house  at  the  Angebilt  Hotel  and  con- 
tinued until  10  o'clock  at  night,  followed 
by  an  elaborate  midnight  banquet  at 
Chef  Manuels. 

IA  President  Walsh  and  International 
Secretary-Treasurer  Raoul,  the  honored 
guests,  were  the  speechmakers  of  the 
evening.  Among  the  out-of-town  guests 
were  A.  S.  Johnstone,  New  Orleans  Local 


Loeiv's  Earnings  Refute  Yelps 
Anent  Film  Industry  'Death' 

Loew's,  Inc.,  which  through  its  ownership 
of  Metro-Goldwyn-Mayer  is  active  in  all 
three  branches  of  the  motion  picture  indus- 
try— production,  distribution,  and  exhibition 
—had  a  net  profit  of  $4,117,117  for  the  28 
weeks  ending  on  March  17  last.  This  figure 
is  after  all  charges,  including  taxes,  and 
also  a  reserve  of  $1  million  for  "contingen- 
cies" and  a  depreciation  write-off  of  $2% 
millions.  Net  profit  in  same  period  last 
year  was  $3,886,745. 


293  and  IA  representative  for  the  7th 
District;  Jake  Pries,  business  representa- 
tive, Local  225,  Atlanta,  Ga.;  Earl 
Walker,  Local  236,  Birmingham,  Ala.; 
John  N.  Spearing,  business  representa- 
tive, Local  511,  Jacksonville;  A.  H. 
Greeley,  business  representative,  Local 
552,  St.  Petersburg;  Arthur  Bowden, 
secretary,  Local  643,  Lakeland;  M.  E. 
Forsyth,  business  representative,  Local 
558,  Daytona  Beach;  C.  W.  Crow,  busi- 
ness representative,  and  J.  W.  Cummings, 
secretary,  West  Palm  Beach;  George 
Raywood,  business  representative,  Local 
316,  Miami;  W.  E.  Sullivan,  business 
representative,  Local  321,  Tampa,  and 
many  others. 

•  We  regret  to  report  the  passing  of  Roy 
Y.  Carlson,  54,  member  of  Denver  Local 
230.  He  was  a  member  of  the  Local 
since  1915,  and  for  the  past  17  years  had 
been  employed  as  projectionist  by  the 
Fox  Inter-Mountain  Theatre  Corp.  Carl- 
son was  one  of  the  founders  and  a  charter 
member  of  the  Francis  Brown  Lowry 
Post  No.  501,  Veterans  of  Foreign  Wars, 
and  a  member  for  the  past  25  years  of 
the  Masonic  Highlands  Lodge  No.  81, 
Colorado  Consistory  No.  2,  and  El  Jebel 
Shrine.  He  is  survived  by  his  widow, 
mother  and  a  sister. 

•  The  poor  projectionist  attendance  at 
the  technical  sessions  of  the  SMPE  con- 
vention held  this  month  in  New  York 
should  serve  notice,  we  think,  to  the 
powers  that  be  that  the  Society's  brush- 
ing aside  from  its  agenda  of  practical 
projection  problems  in  favor  of  the  more 
advanced  technological  aspects  of  kin- 
dred arts  is  finally  bearing  fruit.  We 
have  never  seen  so  few  projectionists  at 
any  SMPE  gathering,  and  we  believe 
that  the  Society's  bid  for  projectionist 
support  should  be  backed  up  with  a 
more  active  interest  in  the  practical 
aspects  of  projection  problems.  At  the 
recent  meetings,  the  closing  half-day 
session  listed  the  only  strictly  projection 
paper  on  the  program. 

•  About  18  months  ago,  nine  members 
of  the  ILGWU's  Winona,  Minnesota, 
Local  were  discharged  by  their  em- 
ployers for  "union  activities."  The  offi- 
cials of  the  Local  refused  to  accept  these 


18 


INTERNATIONAL  PROJECTIONIST 


April  1949 


dismissals  and  fought  to  have  the  em- 
ployes returned  to  their  former  jobs. 
The  Local's  determination  to  protect  the 
welfare  of  its  members  resulted  in  the 
re-instatement  of  the  discharged  workers 
with  back  pay.  The  members  of  this 
Local  are  fortunate  in  the  knowledge 
that  their  interests  are  safeguarded  by 
capable  and  fearless  officials. 

•  Here  are  further  details  on  the  new 
contracts  agreed  to  between  Los  Angeles 
Local  150  and  the  theatre  supply  houses. 
As  we  mentioned  last  month,  Local  150 
members  employed  by  the  supply  houses 
were  given  a  20c-per-hour  increase, 
retroactive  to  December  31,  1948.  Pro- 
jection sales  engineers  now  receive  $133 
per  week,  and  the  cinetechnicians  get 
$106.40.  These  salaries  are  based  on  a 
40-hour  week,  Monday  to  Friday,  with 
time  and  one-half  for  overtime  and  for 
Saturdays  and  Sundays,  and  double  time 
for  holidays.  Emergency  calls  on  Satur- 
days, Sundays  and  holidays  are  4  hours 
minimum.  The  men  are  allowed  7c  per 
mile  for  the  use  of  their  cars  while  on 
the  job.  Projectionists  running  special 
shows  receive  $16,  with  a  4-hour  mini- 
mum call;  each  additional  hour  at  $4. 
Magnus  Nielsen,  the  newly-elected  busi- 
ness representative  for  Local  150,  was 
in  charge  of  negotiations. 

•  Charlie  Muller,  chief  projectionist  for 
Radio  City  Music  Hall,  is  a  mighty 
proud  dad  these  days.  His  daughter, 
Hazel  Barr,  successfully  defended  her 
title  in  the  Metropolitan  Senior  Women's 
Low-Board  Diving  championship.  She 
retained  her  crown  with  a  score  of  96.3 
against  87.8,  the  next  highest  score. 

•  Visiting  the  offices  of  IP  during  the 
past  few  weeks  were  Clarence  Jalas, 
secretary,  Chicago  Local  110;  Jack 
Behlke,  Chicago  Local  110,  field  repre- 
sentative   for    Motiograph;    Frank    Rob- 


bins,  secretary,  Irish  Transport  Workers 
Union,  Dublin,  Ireland;  H.  Paul  Shay, 
Local  289,  Elmira,  N.  Y.,  and  secretary 
for  the  10th  District;  Louis  Williamson, 
business  representative,  Local  186, 
Springfield,  Mass.;  Herbert  Aller,  secre- 
tary-business representative,  Camera- 
men's Local  659,  Hollywood,  Calif.; 
Arthur  Miller,  Local  659  and  three-time 
Academy  Award  winner;  and  Allen  Gor- 
don Smith,  NTS  New  York  City  branch 
manager   (what,  again?). 

•  Taking  his  cue  from  Grandma  Moses, 
who  began  a  successful  painting  career 
when  she  was  well  past  70,  George  H. 
Weil,  member  of  Local  233,  Buffalo, 
N.  Y.,  has  embarked  upon  a  new  hobby — 
landscape  painting.  Weil  has  been  a 
projectionist  for  the  past  37  years,  taking 
up  painting  only  four  years  ago.  He 
began  his  career  as  an  artist  without  any 
formal  instruction,  merely  relying  upon 
a  few  tips  from  a  neighbor  of  his  who 
is  a  portrait  painter.  "You're  never  too 
old  to  start  doing  something  you  really 
enjoy,"  said  Weil.  "As  a  youngster  in 
school,  I  loved  to  work  with  crayons  and 
pencil.  Finally,  I  decided  I'd  like  to  be 
an  artist  and  I  bought  an  easel,  some 
brushes  and  paint  and  went  to  it." 

Although  Weil  paints  just  for  the  love 
of  it,  he  has  sold  several  canvases.  Last 
year  two  of  his  paintings  were  shown  at 
an  industrial  exhibit  in  New  York. 

•  Pete  Benard,  Local  277,  Bridgeport, 
Conn.,  was  elected  president  emeritus 
of  the  Bridgeport  Central  Labor  Union. 
Pete  has  been  interested  in  the  labor 
movement  for  over  half  a  century,  and 
helped  to  organize  Local  277  about  35 
years  ago. 

•  Due  to  the  efforts  of  Bert  Ryde,  busi- 
ness representative  for  Buffalo  Local  233, 
Jack  Sawyer,  member  of  the  Local,  still 
is  at  his  old  stand  as  chief  projectionist 


Sam  Bonansinga 


for  the  Loew  circuit  in  Buffalo.  Due  to 
the  split  in  theatre  interests,  Jack's 
status  was  a  bit  uncertain,  but  a  huddle 
between  Ryde  and  Lester  Isaac,  Loew's 
projection  supervisor,  ironed  things  out 
in  fine  shape. 

•  Our  very  good  friend,  Sam  Bonan- 
singa,  business   representative   of   Local 

138,  Springfield,  111., 
was  recently  appointed 
8th  vice-president  of 
the  Illinois  Federation 
of  Labor.  A  labor 
leader  for  more  than 
30  years,  Sam  has  held 
the  post  of  president 
of  the  Springfield  Fed- 
eration of  Labor  since 
1940,  being  re-elected 
each  year  without  op- 
position. He  has  been 
business  representative 
for  Local  138  since  1918,  and  for  the  past 
22  years  has  been  stage  manager  of  the 
Orpheum  Theatre  in  Springfield.  He  is 
extremely  popular  in  labor  circles  and 
is  held  in  high  esteem  by  his  associates. 
To  sum  it  all  up,  Sam  Bonansinga  repre- 
sents the  type  of  labor  leader  we  proudly 
call  our  own. 

•  We  were  glad  to  hear  that  Harry 
Barco,  business  representative  for  St. 
Louis  Local  143,  has  completely  re- 
covered from  a  gall-bladder  operation 
and  is  back  on  the  job. 

•  One  of  our  overseas  subscribers,  Frank 
Robbins,  from  Dublin,  Ireland,  paid  us  a 
surprise  visit  last  month.  He  is  secretary 
of  the  Theatre  and  Cinema  branch  of  the 
Irish  Transport  and  General  Workers 
Union,  and  is  spending  several  months 
in  this  country  to  get  first-hand  informa- 
tion on  the  many  phases  of  American 
know-how  in  technical  and  organizational 


MEMBERS  AND  GUESTS  AT  RECENT  LOCAL  631,  ORLANDO,  FLA.,  TWENTY-FIFTH  ANNIVERSARY  CELEBRATION 


Grogan  Photo  Co.,  Orlando,  Fla. 
Standing  (left  to  right):  A.  H.  Greely,  L.  552,  St.  Petersburg;  Arthur  Bowden,  L.  643,  Lakeland;  Brack  Beasley,  Pat  Grier,  L.  631,  Orlando;  Fred 
Raoul,  L.  225,  Atlanta  (Ga.);  Ed  Forsyth,  L.  558,  Daytona  Beach;  Arthur  Pope,  F.  B.  Eades,  John  Lovejoy,  Walter  Creamer,  L.  631,  Orlando;  C.  W. 
Crow,  L.  623,  West  Palm  Beach;  Geo.  Raywood,  L.  316;  Miami;  Paul  Buress,  L.  666,  Chicago  (III.);  J.  W.  Cummings,  L.  623,  West  Palm  Beach; 
Angelo  Sands,  L.  545,  Miami;  R.  M.  Sligh,  L.  115,  Jacksonville;  Leon  Cazin,  W.  E.  Sullivan,  L.  321,  Tampa;  John  Bender,  L.  552,  St.  Petersburg;  Geo. 
Dougherty,  R.  B.  Ambrose,  L.  631,  Orlando;  Spencer  Locke,  president,  Central  Labor  Council;  Shields  Bennett,  L.  643,  Lakeland;  Earl  Walker  L.  236, 
Birmingham  (Ala.);  B.  L.  Bradford,  L.  643,  Lakeland;  Dan  Altomond,  L.  631,  Orlando. 

Seated  (left  to  right):  Chas.  Toy,  L.  115,  Jacksonville;  A.  M.  Johnstone,  L.  293,  New  Orleans  (La.);  IA  President  Richard  Walsh;  J.  B.  McGee, 
L.  631,  Orlando;  General  Sec.-Treas.  W.  P.  Raoul;  J.  N.  Spearing,  L.  511,  Jacksonville;  Richard  Gabel,  L.  631,  Orlando;  Jake  Pries,  L.  225,  Atlanta 
(Ga.);  R.  Noble,  L.  552,  St.  Petersburg;  Joe  Sanders,  Jim  Scobie,  L.  412,  Sarasota;  J.  M.  Vost,  L.  558,  Daytona  Beach;  A.  H.  Montgomery,  L.  462, 

Vineland  (N.  J.);  L.  R.  Moss  and  W.  Hoffman,  L.  631,  Orlando. 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


19 


matters.  The  IT&GWU  differs  from  our 
own  IA  in  that  it  admits  to  membership 
everybody  working  in  a  theatre — projec- 
tionists, stagehands,  chorus  girls,  char- 
women, porters,  cashiers,  etc. 

Robbins  was  very  much  impressed  with 
his  visits  to  Radio  City  Music  Hall  and  to 
the  RCA  Exhibition  Hall.  Charlie  Mul- 
ler,  chief  projectionist  at  the  Music  Hall, 
took  Frank  on  a  personally-conducted 
tour  through  this  world-renowned  estab- 
lishment; and  at  the  Exhibition  Hall 
both  Charlie  Kellner  and  Mike  Springer 
made  his  visit  a  most  pleasant  and  in- 
formative one. 

•  Frank  Morrison,  secretary  of  the  AF 
of  L  for  43  years  until  his  retirement  in 
1940,  died  last  month  at  the  age  of  89. 
A  prominent  figure  in  the  labor  move- 
ment, he  saw  the  AF  of  L  grow  from  a 
membership  of  250,000  to  its  present 
strength  of  nearly  8,000,000  members. 
He  devoted  his  life  to  the  cause  of  labor 
and  proved  a  very  good  friend  to  the 
International  Alliance  in  its  early 
struggles. 

•  The  10th  Anniversary  celebration  for 
Local  723,  Norwood,  Mass.,  was  held 
last  month  at  the  Fox  and  Hounds  Club, 
Boston.  It  was  a  gala  evening,  topped 
with  plenty  of  refreshments  and  enter- 
tainment. Among  the  invited  guests 
were  IA  Representative  Wm.  C.  Scanlan; 
Joseph  Nuzzolo,  president,  and  Walter 
F.  Diehl,  business  representative,  Boston 
Local  182,  and  Delmont  Merrill,  business 
representative,  Waltham  Local  505. 

•  We  regret  to  report  the  passing  of 
another  old-timer.  Roy  Grove,  old-line 
member  of  Pittsburgh  Local  171  and 
projectionist  at  the  Stanley  Theatre  for 
more  than  20  years,  died  after  a  linger- 
ing illness.  During  our  many  years  of 
traveling   around  the   country,  we  never 


Unique  Method  of  Alternate-Frame,  16-mm  Projection 


By  H.  HILL 
British  Observer  for  IP 

SINCE  the  inception  of  16-mm  sound 
motion  pictures  the  sound  reproduc- 
tion of  such  films  has  always  been  at  a 
great  disadvantage  to  its  bigger  brother, 
the  35-mm  soundfilm.  The  great  differ- 
ence in  relative  film  speeds  is  that  with 
16-mm  film  reduction  printing  must  be 
employed,  with  its  consequent  losses  and 
inefficiencies,  and  that  very  fine  slits  must 
be  used  to  obtain  reproduction  in  the 
upper  frequencies. 

This  situation  has  been  altered  radi- 
cally by  the  introduction  of  an  ingenious 
projector  which  combines  some  of  the 
advantages  of  both  35-  and  16-mm  sound- 
film.  The  high  quality  of  visual  and 
sound  reproduction  afforded  by  this  unit 
promises  a  bright  future  for  the  equip- 
ment and  the  system  it  employs. 

Developed  in  London  after  40  years  of 
experimentation  by  Martin  Harper,  this 
unorthodox  device  is  certainly  a  most 
significant  technological  development. 

Alternate-Frame  Projection  Used 

Realizing  the  tremendous  scope  of  16- 
mm  film  usage,  Harper  hit  upon  the  idea 
of  doubling  the  speed  of  the  film  and,  as 
a  necessary  concomitant,  projecting  alter- 
nate frames.  This,  of  course,  brought 
the  linear  film  speed  into  conformity 
with  35-mm  soundfilm  and  permitted  the 
soundtrack  to  be  contact-printed  direct 
from  35-  to  16-mm  film.  The  device  was 
patented  in  England  in  1938. 

This  process  requires  special  film  and 

passed  through  Pittsburgh  without  stop- 
ping off  at  the  Grove  home.  We  lost  a 
very  good  and  sincere  friend  when  Roy 
Grove  passed  on. 


MEMBERS  OF  KANSAS  CITY  LOCAL  170-A  MEET  WITH  ST.  LOUIS  LOCAL  143-A  MEN 


Television  in  the  theatre  was  the  chief  topic  of  conversation  at  the  meeting  held  recently  between 
Local  170-A  and  Local  143-A  men.  Pictured  above,  taking  part  in  the  discussions,  were  (front 
row):  L.  H.  Parker,  secretary.  Local  143-A;  Jack  C.  Pickett  (standing),  board  member.  Local  170-A; 
H.  Cuffie,  business  representative,  Local  143-A;  Norval  G.  Parker,  president.  Local  170-A.  (Back 
row):  Wm.  S.  Thompson,  vice-president.  Local  170-A;  Mel  T.  Tivis,  treasurer,  Local  170-A; 
M.  William  Walker,  secretary.  Local  170-A;  George  L.  Smith,  president.  Local  143-A;  Orville 
Copeland  and  John  H.  Adams,  Jr.,  members  of  Local  170-A. 


a  suitable  non-standard  projector  with 
which  to  use  it.  The  accompanying 
sketch  shows  how  this  film  is  constructed. 
Instead  of  the  usual  perforations  down 
the  side  of  the  film,  they  are  placed 
between  the  alternate  frames,  arranged 
in  alternate  ones  and  twos.    The  frames 


Construction  of  the  Harper 
film  strip.  Perforations  are 
placed  between  alternate 
frames,  which  are  pro- 
jected alternately.  Sound 
tracks  are  at  each  side  of 
the  film. 


are  projected  alternately;  and  when  the 
film  has  been  run  through  the  projector 
once  it  is  simply  re-threaded  and  run 
back  in  reverse,  utilizing  the  inverted 
frames  which  were  unused  on  the  pre- 
ceding run. 

System's  Advantages,  Limitation 

The  respective  soundtracks  are  at  each 
side  of  the  film,  and  since  the  track  is 
contact-printed  direct  from  35-mm  film, 
it  means  that  the  running  speed  must  be 
90  feet  per  minute. 

The  advantages  of  this  novel  method 
of  16-mm  projection  are:  (1)  high- 
quality  sound;  (2)  no  rewinding  of  film 
in  certain  cases;  (3)  perfectly  steady 
picture,  and  (4)  Maltese-cross  movement. 
Its  limitation  is  that  it  requires  special 
film  which  cannot  be  projected  on  stand- 
ard projectors. 

Recently  a  projector  has  been  devel- 
oped which  will  project  both  standard 
and  the  Harper  films.  This  equipment 
is  a  precision  machine  through  the  use 
of  which  film  damage  is  almost  com- 
pletely eliminated.  Although  these  units 
are  not  yet  available  generally,  a  vast 
extension  of  its  use  is  looked  for  within 
the  not  too  distant  future. 


PERSONAL    NOTES 


Stephen  Wiedmann  has  been  appointed 
vice-president  in  charge  of  Alpine  Western 
Electric  Co.,  announces  the  Westrex  Corp. 
During  the  past  year  he  supervised  Westrex 
activities  in  Norway,  Sweden  and  Finland. 

H.  Tscherning  Petersen,  manag-er  of 
Western  Electric  of  Denmark,  will  tempor- 
arily assume  managership  of  Stockholm, 
Sweden,  office,  dividing  his  time  between 
both  cities. 

Joseph  G.  Csida,  for  more  than  15  years 
associated  with  The  Billboard,  has  joined 
the  RCA  Victor  Division  of  RCA  as  assistant 
director  of  public  relations. 


20 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


Lens  Design  and  Manufacture 


CAMERA  and  projection  lenses  are 
made  of  optical  elements,  concave 
or  convex  in  form  according  to  the 
design  which  has  been  arrived  at  mathe- 
matically by  the  lens  computer,  and  in 
various  types  of  optical  glass.  These 
different  optical  glasses  possess  charac- 
teristic physical"  properties  but  are  quite 
indistinguishable  one  from  another  to 
the  unaided  eye. 

The  properties  in  which  the  optical 
designer  is  particularly  interested  are 
refractive  index  and  dispersive  power. 
It  is  necessary  to  have  available  a  great 
variety  of  types  of  optical  glass  to  enable 
the  designer  to  reduce  to  a  minimum  the 
aberrations  peculiar  to  the  particular  lens 
system  he  is  designing. 

The  properties  required  to  be  known 
by  the  lens  designer  are  characteristic 
not  only  of  the  type  of  glass  but  of  each 
melt  of  glass,  and  are  dependent  upon 
the  chemical  composition  of  the  glass. 
Optical  glass  consists  mainly  of  silica — 
that  is,  sand — together  with  sodium  and 
potassium  carbonates  and  other  metallic 
salts  which  impart  particular  properties. 

Good  Optical  Glass  Requisites 

The  art  of  making  good  optical  glass 
lies  in  the  melting  together  of  the  chemi- 
cals to  produce  a  glass  which  is  free 
from  color  and  inclusions,  uniform  in 
chemical  and  physical  characteristics, 
while  possessing  a  high  degree  of 
stability. 

When  reasonable  quantities  of  lenses 
are  to  be  made,  it  is  usual  to  commence 
with  mouldings  approximating  the  shape 
of  the  finished  elements.  When  small- 
quantity  production  has  to  be  carried 
out,  the  blanks  are  cut  roughly  to  shape 
from  slab  glass,  using  a  diamond-loaded 
saw.  It  will  be  appreciated  that  it  is 
less  economical  to  cut  from  slab  glass 
than  to  start  from  a  moulded  shape. 

Each  melting  of  a  particular  type  of 
glass  has  its  own  physical  characteristics, 
and  the  optical  designer  must  know  them 
to    great    accuracy.     There   are   various 


Supplementing  the  wealth  of  data  on 
optics  which  has  appeared  in  IP  re- 
cently is  this  paper,  delivered  before 
the  British  Kinematographic  Society, 
which  constitutes  a  worthy  addition 
to  the  literature  of  the  art. 

By  A.  HOWARD  ANSTIS 

instruments  available  for  measuring  the 
refractive  index  and  dispersive  power. 
Samples  of  each  melting  are  tested  as 
received  from  the  glass  manufacturer, 
and  the  constants  are  recorded  for  use 
in  subsequent  lens  calculations. 

The  lens  data,  specifying  the  melts  of 
glass  to  be  used,  the  diameters,  radii  of 
curvature,  and  thicknesses  of  the  various 
elements,  are  passed  to  the  works  from 
the  design  department. 

For  small-quantity  production  the  sur- 
faces of  the  blanks  are  roughed  to  curva- 
ture by  hand.  The  operator  rubs  the 
blank  against  the  surface  of  a  rotating 
spherical  tool  made  of  brass  or  cast  iron, 
while  feeding  on  coarse  carborundum  and 
water  as  abrasive.  For  larger  quantity 
production  the  blanks  are  spherically 
milled  with  diamond-loaded  milling  tools. 

Lens  Grinding  Process 

Lens  elements  have  a  spherical  surface 
on  both  sides,  and  each  surface  has  to 
be  processed  separately.  One  side  is 
rough-ground,  smooth-ground,  then  pol- 
ished. This  is  then  repeated  on  the  other 
side,  bringing  the  center  thickness  of 
the  element  to  its  computed  value,  and 
the  element  is  then  edge-ground  to  the 
diameter  specified. 

The  abrasive  used  for  rough  grinding 
is  quite  coarse.  For  smooth  grinding  a 
range  of  fine  abrasives  is  used,  until  a 
very  smooth  surface  is  finally  obtained. 
The  action  of  polishing  is  to  smooth  out 
the  fine  pits  left  by  the  grinding,  the 
surface  of  the  glass  actually  flowing. 


Comparison  of  uncoated 
(left)  and  coated  pro- 
jection lenses,  showing 
marked  reduction  in 
reflections  and  freedom 
from  glare  in  the  coated 
lens. 


Hi 

lllit 

^nTrr^-j — ~~ 

\  Ik  HE  - 

~ 

F* 

'      "  'mU 

1 ';; 

INTERNATIONAL  PROJECTIONIST     •     April  1949 


It  is  convenient  to  perform  this  smooth 
grinding  and  polishing  with  the  lens 
blanks  stuck  with  pitch  on  so-called  run- 
ners, so  that  many  can  be  processed  at 
one  time:  they  then  form  what  is  called 
a  block  of  lenses.  The  number  of  lenses 
that  can  be  accommodated  on  a  block 
will  depend  on  the  diameter  and  the 
radius  of  curvature. 

The  blanks  are  sometimes  roughed 
singly  and  stuck  into  a  block,  or  some- 
times the  blanks  are  roughed  as  a  block 
by  being  cemented  into  recesses  in  a 
machined  runner.  The  roughed  block  of 
lenses  is  then  screwed  onto  the  spindle 
of  a  smoothing  machine  for  smooth 
grinding.  The  size  of  the  machine  used 
will  depend  on  the  radius  of  curvature 
of  the  block,  but  the  principle  is  always 
the  same. 

The  block  is  rotated  on  a  vertical 
spindle  and  the  grinding  tool  moved  in 
an  oscillatory  motion  over  the  surface 
of  the  lenses.  Emery  and  water  is  used 
as  abrasive,  and  the  lapping  is  continued 
with  successively  finer  grades  of  abrasive 
until  the  surface  is  of  a  sufficiently  fine 
greyness  for  polishing. 

The  same  type  of  machine  is  used  for 
polishing  (the  polishing  tool  being 
similar  to  the  grinding  tool)  by  having 
a  layer  of  about  1/6  inch  of  pitch  on 
the  surface.  The  polishing  tool  moves 
over  the  ground  surface  of  the  lenses, 
lubricated  by  rouge  or  other  metallic 
oxides  and  water. 

Checking  Radius,  Sphericity 

Quite  a  high  degree  of  polish  is  ob- 
tained after  30  minutes,  and  it  is  then 
that  the  operator  commences  to  take  an 
interest  in  the  figure  of  the  surface.  By 
"figure"  is  meant  the  shape  of  the  sur- 
face being  produced.  The  lens  surface 
must  be  perfectly  spherical  and  must  also 
comply  accurately  with  the  designed 
radius  of  curvature.  The  surface  is 
tested  by  means  of  a  glass  plate  which  is 
of  opposite  curvature  to  the  surface 
being  produced. 

Interference  fringes,  known  as  "New- 
ton's rings,"  are  obtained  between  the 
surface  and  the  test  plate:  by  means  of 
these  fringes  the  departure  from  radius 
of  curvature  and  sphericity  of  the  surface 
under  test  can  be  ascertained  to  great 
accuracy.  After  several  hours  polishing, 
the  block  will  be  fully  polished  and  also 
acceptable  for  curvature. 

The  making  of  the  test  plates  is  a 
very  skilful  task,  involving  much  check- 
ing by  interference  fringes  and  for  radius 
of  curvature. 

The  highest  quality  grinding  and 
polishing  still  is  performed  by  hand  by 


21 


skilled  craftsmen.  With  large  lenses  and 
prisms,  it  is  very  difficult  to  produce  the 
glass  perfectly  homogeneous.  If  inhomo- 
geniety  of  the  glass  is  indicated,  then 
one  surface  of  the  lens  or  prism  is  rubbed 
by  a  small  polisher  to  deform  the  surface 
so  as  to  neutralize  the  effect:  only  a  few 
wave-lengths  of  glass  would  be  so  re- 
moved. 

The  removal  of  the  lenses  from  the 
pitch  is  facilitated  by  putting  the  blocks 
of  lenses  into  a  refrigerator.  The  pitch 
contracts  at  a  different  rate  to  the  lenses 
and  the  lenses  can  easily  be  removed 
quite  clean. 

Edge-Grinding  and  Assembly 

Lenses*  after  being  polished  on  both 
surfaces,  have  to  be  edge-ground  so  that 
the  optical  axis  is  true  with  the  edge. 
To  do  this  the  lens  is  stuck  with  wax 
onto  a  chuck.  The  lens  is  warmed  and 
moved  on  the  chuck  until  reflected 
images  seen  in  the  lens  surfaces  are 
perfectly  steady.  The  spindle,  together 
with  the  lens,  is  then  transferred  to  a 
mechanical  edge-grinding  machine  and 
the  lens  is  edged  to  the  correct  diameter. 

For  work  of  the  highest  accuracy,  the 
lenses  are  edge-ground  by  hand,  the 
operator  checking  the  concentricity  of 
the  lens  continually.  Chamfers  are  pro- 
duced at  the  same  time  as  edging. 

Lenses  which  have  to  be  cemented  are 
now  stuck  together  with  Canada  balsam, 
and  set  up  concentric  on  a  chuck  as  if 
setting  up  for  edging.  The  lenses  are 
then  ready  for  mounting  and  are  bevelled 
into  their  cells.  The  cells  are  assembled 
into  the  lens  bodies,  and  the  completed 
lenses  are  ready  for  test. 

Anti-Reflection  Coating  of  Lenses 

When  visible  light  passes  through  an 
optical  system,  about  2%  is  absorbed 
per  centimeter  of  glass.  At  each  air-glass 
or  glass-air  transmitting  surface  between 
4  and  8%  is  lost  by  reflection,  dependent 
on  the  refractive  index  of  the  glass.  The 
reflected  light  which  is  lost  suffers  mul- 
tiple reflection  between  the  lens  surfaces 
and  finally  makes  its  presence  felt  as  a 
general  background  of  illumination  in 
the  image,  whether  photographic  or  pro- 
jected, causing  a  reduction  in  contrast. 
In  bad  cases,  flare  spots  are  present  also. 

By  means  of  surface  coating,  very 
nearly  all  the  reflected  light  is  eliminated, 
passing  instead  through  the  system  to 
increase  the  brightness  of  the  image. 
The  prime  advantages  of  surface  coating 
are,  therefore,  increased  transmission  and 
improved  contrast.  The  film  is  only  a 
few  millionths  of  an  inch  in  thickness, 
being  produced  in  high-vacuum  plants. 

The  surface  treatment  of  lenses  has 
opened  the  way  to  more  complicated  lens 
systems,  since  the  necessity  of  keeping 
the  number  of  elements  to  a  minimum 
has  been  largely  removed.  The  large- 
aperture  projection  lenses  now  employed 


resemble  photographic  anastigmat  lenses 
more  and  more  in  their  construction. 
The  separation  of  the  various  elements  is 
critical,  and  if  dismantled,  the  lens  has 
to  be  very  carefully  re-assembled.  Such 
lenses  should  therefore  be  sealed. 

Transmission  Calibration  Scale 

To  quote  an  example  of  the  increase 
in  transmission  caused  by  blooming:  one 
class  of  F:3.5  lenses  has  a  transmission 
of  70%  prior  to  blooming  and  91%  after 
blooming. 

The  transmission  difference  between 
various  makes  of  lens,  bloomed  and  un- 
bloomed,  when  set  to  the  same  aperture 
value,  has  become  serious  in  the  case  of 
taking  lenses  for  color  films,  and  it  has 
been  proposed  to  mark  photographic 
lenses  with  a  transmission  scale.  The 
scale  will  take  into  consideration  the 
light-transmitting  power  of  the  lens,  so 
that  all  lenses  of  whatever  make,  bloomed 
or  unbloomed,  would  transmit  exactly  the 
same  amount  of  light  when  set  to  the 
same  T-number.* 

There  are  mechanical  and  optical  tests 
to  be  applied  to  the  finished  lenses,  and 
from  an  optical  point  of  view  the  focal 
length  and  resolution  are  the  important 
criteria. 

Formulating  Resolution  Data 

Photographic  lenses  were  formerly 
tested  by  photographing  a  test  chart  to 
ascertain  that  the  resolution  was  satisfac- 
tory over  the  area  to  be  covered  by  the 
lens.  The  testing  of  long  focus  lenses 
in  this  way  is  costly,  as  the  plates  are 
very  big;  also  much  storage  room  is 
required  to  keep  the  records  of  lenses 
which  have  been  manufactured.  A 
method  of  test  was  devised,  therefore, 
which  enables  the  equivalent  focal  length 
of  the  lens  to  be  ascertained,  and  at  the 
same  time  test  visual  and  photographic 
resolution. 

The  instrument  used  is  called  a  "nodal 
slide".    The  lens  under  test  is  arranged 


*  See  "T-Number  vs.   F-Number  Lens  Markings,"  IP 
for  March,   1949,   p.  17. 


Coarse  emery  particles  at   12x  magnification. 
These  sharp  particles  are  used  in  grinding  lenses. 


by  trial  so  that  a  pivoting  point  on  the 
lower  carriage  passes  through  the  back 
nodal  point.  In  front  of  the  lens  is  a 
collimator  with  a  resolution  graticule. 
The  image  of  this  resolution  graticule, 
called  a  Cobb-type  test  object,  is  focused 
by  the  microscope  and  the  visual  resolu- 
tion as  the  lens  is  swung  through  any 
angle  can  be  examined. 

The  photographic  resolution  on  any 
type  of  emulsion  can  be  determined  by 
removing  the  microscope  and  putting  a 
2%  x  3%-inch  plate  into  the  repeating 
back  of  the  instrument.  A  series  of 
resolution  photographs  is  made  with  the 
lens  rotated  through  various  angles,  then 
further  sets  of  photographs  are  made  in 
and  out  of  the  visual  focus  position. 

In  this  way,  the  resolution  data  for 
any  focal  length  lens  can  be  obtained 
on  a  very  small  plate.  The  equivalent 
focal  length  of  the  lens  is  shown  on  a 
scale  and  is  the  distance  between  the 
pivoting  point  and  the  focal  plane. 

Projection  lenses  are  tested  usually  for 
resolution  and  focal  length  on  a  small 
nodal  slide,  and  then  finally  in  an 
ordinary  projector,  using  a  piece  of 
transparent  quartz  bearing  a  multitude 
of  fine  detail  as  the  test  object. 

A  foco-collimator  is  used  for  the  pre- 
cise determination  of  the  equivalent  focal 
length  of  short  focus  lenses.  Special 
test  benches  are  used  for  testing  enlarg- 
ing and  process  lenses,  also  for  testing 
such  lenses  as  wide-angle  survey  and 
gauge  projection  lenses,  for  which  free- 
dom from  image  distortion  is  the  impor- 
tant criterion. 

The  standardization  of  a  transmission 
scale  is  one  of  a  number  of  optical 
matters  at  present  receiving  consideration 
by  the  British  Standards  Institution.  An- 
other example  is  a  recent  draft  specifica- 
tion for  35-mm  projection  lenses  which 
makes  provision  for  a  barrel  diameter  of 
80  mm,  permitting  a  range  of  lenses 
working  at  F:1A.  This  indicates  the 
trend  of  new  design. 

The  popular  projection  lens  barrel 
diameter  size  in  the  past  was  52.4  mm, 
but  more  recently  with  the  introduction 
of  F:1.9  collecting  systems  and  lenses 
to  match,  the  70.65  mm  diameter  jacket 
has  become  almost  universal.  There  are, 
however,  certain  mechanical  restrictions 
in  some  projectors  which  do  not  permit 
the  use  of  this  larger  diameter  jacket  in 
all  focal  lengths. 

Modern  projection  lenses  are  surface- 
treated  and  hermetically  sealed,  the  inner 
optical  surfaces  are  thus  always  clean, 
and  the  projectionist  need  only  wipe  over 
the  external  surfaces. 

Discussion : 

Question.  To  what  light  does  the  quarter 
wave-length  refer?  Is  the  transmission  selec- 
tion according  to  the  wave-length  of  light? 

Answer.    We   generally  coat   the   surfaces 

(Continued  on  page  26) 


22 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


RCA's  Kinephoto  System  for  Tv-to-Film   Transfer 


RCA  has  given  the  first  public  demon- 
stration of  its  new  Kinephoto  system 
for  recording  Tv  images  on  motion  pic- 
ture film.  The  system  consists  of  a 
Kinephoto  equipment  (Type  TMP-20B) 
which  is  basically  a  projection-type  kine- 
scope, with  its  associated  video  amplifier, 
deflection  circuits,  and  power  supplies; 
and  a  suitable  16-  or  35-mm  soundfilm 
camera. 

The  equipment  utilizes  standard  video 
signals  supplied  directly  to  the  unit  from 
the  switching  system  in  the  Tv  studio. 
The  signal  is  fed  to  a  video  amplifier, 
where  it  is  amplified  and  separated  into 
a  signal  for  synchronizing  the  scanning 
raster  of  the  kinescope  with  that  of  the 
Tv  pickup  camera,  and  a  modulating 
signal  which  is  amplified  and  used  to 
control  the  kinescope  beam  which  forms 
the  visual  image. 

A  regulated  power  supply  furnishes 
necessary  plate  voltages  to  all  units,  in- 
cluding the  25  kv  required  for  kinescope 
operation.  The  control  functions  of  the 
equipment  are  grouped  on  a  central 
panel  with  metering  circuits  to  indicate 
proper  operating  adjustments. 

The  kinescope  (Type  5WP11)  is  a 
special  5-inch,  flat-face  aluminized,  pro- 
jection-type cathode-ray  tube  having  a 
short-persistence  blue  phosphor  screen 
of  high  actinic  value,  which  makes  pos- 
sible the  use  of  high-resolution,  low-cost, 
positive-type  film  stock. 

Timing   Difference   Compensation 

In  addition  to  the  Kinephoto  unit,  the 
system  requires  a  16-mm  motion  picture 
recording  camera.  This  camera  compen- 
sates for  the  timing  differences  between 
the  Tv  system,  which  has  a  scanning 
frequency  of  30  complete  frames  or  60 
interlaced  fields  per  second,  and  the 
conventional  motion  picture  system  of  24 
frames  per  second.  Since  1/12  of  a 
second  is  the  time  interval  for  five  inter- 
laced Tv  fields  and  for  two  frames  of 
film,  compensation  can  be  made  by  ex- 
posing each  film  frame  for  the  duration 
of  two  Tv  fields  and  advancing  the  film 
during  an  interval  representing  one  Tv 
field  out  of  five. 

Because  of  differences  in  phasing,  each 
film  frame  may  represent  parts  of  as 
many  as  three  Tv  fields,  but  a  precision 
timing  shutter  and  pull-down  mechanism 
provides   for   precise   matching   between 


the  cutoff  point  in  one  field  and  the  point 
of   pickup   in   the   next. 

The  camera  exposure  time  in  terms  of 
the  Tv  system  must  be  accurate  to  less 
than  %  scanning  line,  or  roughly  one 
part  in  30,000.  It  must  be  timed  to 
expose  exactly  the  proper  number  of 
picture  lines  for  each  frame,  or  525  lines, 
no  more  or  less,  or  an  effect  known  as 
"banding"  will  take  place  on  the  exposed 
film.  This  exposure  is  controlled  by  a 
mechanical  shutter. 

The  camera  and  shutter  are  driven  by 
synchronous  motors  which  are  synchro- 
nized with  the  entire  Tv  system.  The ' 
shutter  drive  is  isolated  from  the  main 
camera  drive,  and  a  3600-rpm  synchro- 
nous motor  drives  the  shutter  at  the 
necessary  1440-rpm  through  a  set  of 
precision  gears.  Another  motor,  syn- 
chronized with  this,  drives  the  film  trans- 
port and  intermittent  mechanism.  This 
arrangement  insures  rotational  accuracy 
and  freedom  from  inter-action. 

Density  of  Film  Recording 

The  density  of  film  recording  depends 
not  only  on  the  length  of  exposure  but 
on  the  brightness  of  the  cathode-ray 
picture  tube.  Since  the  exposure  time 
is  fixed,  the  highlight  brightness  of  the 
picture  is  varied  by  means  of  the  video 
gain  control;  the  kinescope  bias  control 
will  set  the  black  level  or  point  of  visual 
extinction  of  the  return  lines.  The  beam 
current  of  the  picture  tube  is  measured 
by  a  microammeter  on  the  control  panel 
of  the  monitor:  since  there  is  a  direct 
relationship  between  this  current  and  the 
fight  output  of  the  tube,  the  measurement 
of  the  beam  current  provides  a  good  in- 
dex to  the  brightness  of  the  picture. 

Normally,  the  positive  kinescope  im- 
ages are  filmed  on  standard  stock,  pro- 
ducing negative  film  images  which  can 
be  used  for  rebroadcast  by  reversing  the 
video  phase  in  the  Tv  camera.  The  nega- 
tive is  then  available  to  produce  as  many 
positive  prints  as  desired.  For  applica- 
tions where  quick  processing  and  projec- 
tion  is   required,   such   as  in  theatres,  a 


Terrific  CBS  Tv  Surge 

Progress  Report:  Tv  advertising  volume 
on  Columbia  Broadcasting  System  for  the 
first  three  months  this  year  was  40  times 
(not  40%  but  40  times)  greater  than  for 
the  comparable  period  during  1948. 


polarity  switch  makes  it  possible  to  ad- 
just the  kinescope  to  produce  negative 
images.  Such  images  can  be  photo- 
graphed and  processed  as  direct  film 
positives  for  immediate  projections. 

RCA  asserts  that  with  Kinephoto  it 
is  possible  to  project  the  finished  pictures 
within  40  seconds  after  they  are  filmed. 
Using  this  technique,  theatres  could  take 
pictures  "off  the  air,"  rush  them  through 
processing,  and  use  standard  film  pro- 
jectors to  show  them  as  newsreels. 

16-mm  Wins  Wide  Acceptance 

Either  16-  or  35-mm  cameras  can  be 
used  with  Kinephoto.  The  16-mm  film 
has  been  chosen  initially  because  of  the 
importance  of  costs  of  film  stock  and 
film  processing,  together  with  the  safety 
problems  involved,  that  16-mm  fine-grain 
films  with  suitable  processing  can  pro- 
duce excellent  picture  quality,  at  a  cost 
of  about  1/3  that  of  35-mm  film.  Con- 
sidering that  it  takes  1200  feet  of  film 
to  record  a  half-hour  performance,  cost 
of  film  and  developing  is  an  important 
factor. 

The  camera  can  be  equipped  with 
RCA  sound  recording  equipment  to  place 
the  sound  track  and  picture  on  the  same 
film,  or  the  sound  signals  may  be  fed 
to  a  separate  sound  recorder  which  per- 
mits editing,  re-recording,  and  dubbing. 

The  Kinephoto  system  uses  a  power 
source  of  110-120  volts,  60  cycles,  750 
watts.  The  input  impedance  is  72  ohms. 
The  equipment,  exclusive  of  camera,  is, 
in  inches,  50  long,  26  wide  and  56  high, 
and  weighs  about  500  pounds. 


New  RCA  Life-Size  Tv  System 

A  new  life-size  Tv  projection  system 
(TLS-87)  featuring  an  optical  barrel 
which  for  the  first  time  is  suspended  from 
a  convenient  ceiling  mounting,  has  been 
announced  by  RCA.  Construction  is 
such  that  all  the  equipment  can  be  out 
of  the  way  of  the  viewing  audience. 

In  use,  the  optical  barrel  is  focused 
on  a  screen  up  to  6-  x  8  feet  in  size,  of 
either  front-  or  rear  projection  type.  The 
optical  barrel  is  connected  to  the  control 
console  by  a  40-foot  cable. 

The  TLS-87  has  a  30-watt  amplifier, 
with  microphone  and  phonograph  inputs 
provided  so  that  the  unit  can  be  used  as 
a  public  address  system  when  Tv  pro- 
grams are  not  on  the  air.  The  amplifier 
also  can  be  used  in  conjunction  with  a 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


23 


record  player  or  with  wired  music.  Ap- 
propriate types  of  loudspeakers  can  be 
utilized  to  meet  the  requirements  of 
various  types  of  installations. 


Tv  Will  Help  Not  Hurt  Movies, 
Soys  Paramount  Video  Head 

Television  has  already  indicated  that  it 
will  be  responsible  for  the  ultimate  elimina- 
tion of  the  "B"  picture  but  has  thus  far  pro- 
duced no  serious  competition  for  top  quality 
film  product,  Paul  Raibourn,  Paramount, 
vice-president,  told  the  Investment  Bankers 
Association,  in  an  address  recently. 

Raibourn  expressed  the  opinion  that  "dur- 
ing the  next  several  decades  Tv  will  have 
become  a  feature  in  the  American  home 
without  the  slightest  setback  to  all  those 
other  industries  which  satisfy  the  wants  of 
leisure  time,  namely,  the  motion  picture,  the 
newspaper,  the  magazine,  the  automobile  or 
the  'dress  up'  apparel  business."  Raibourn 
admitted  that  theatre  attendance  among 
video  set  owners  had  declined  about  25  per 
cent,  but  said  that  this  loss  would  eventually 
be  more  than  recovered  when  video  was 
used  as  a  promotion  medium  for  pictures. 

Sees  Tv  as  'Marvelous'  Theatre  Aid 

"The  Tv  set  in  the  home  is  going"  to  be 
such  a  marvelous  instrument  for  making 
people  want  to  see  motion  pictures  that  one 
wonders  sometimes  if  it  wasn't  just  devised 
for  that  purpose,"  the  Paramount  Tv  chief 
declared.  "Only  15,000,000  of  America's 
148,000,000  see  the  average  so-called  'A'  pic- 
ture. I  feel  ashamed  of  our  advertising  and 
publicity  work  when  I  give  you  those  figures. 
But  there  are  limitations  to  the  static  printed 
page  in  portraying  the  appeal  of  the  action 
in  our  features. 

"We  believe  that  there  is  no  way  of  mak- 
ing a  person  hungry  as  completely  effective 
as  that  of  giving  him  a  small  taste  of  a  de- 
lectable dish.  Through  a  Tv  broadcast  we 
will  come  into  your  home  to  show  you  just 
enough  of  a  picture  to  make  you  hungry  for 
the  rest  of  it.  And  if  you  don't  come  to  the 
motion  picture  theatre  to  see  it  after  that, 
then  either  we  have  done  a  bad  job  or  you 
are  becoming  old  and  blase.  We  will  take 
care  of  the  first  part.  We  believe  you  will 
take  care  of  the  second." 


image.  Gordon  contends,  further,  that  when 
Tv  film  producers  can  afford  to  use  35-mm 
film  and  equipment,  instead  of  16-mm  re- 
duction prints,  the  definition  now  lacking  in 
televised  films  will  be  present. 

In  explaining  the  mechanics  of  kinescope 
recording,  wherein  a  live  Tv  show  is  photo- 
graphed, Gordon  again  feels  that  the  use 
of  35-mm  film  will  improve  immeasurably 
the  quality  of  reproduction,  and  will  more 
nearly  approximate  the  quality  of  the  live 
show. 


Fine-Grain  35-mm  Positive  for  Tv 

Substitution  of  low-contrast,  fine-grain 
positive  film  for  standard  projection  prints, 
and  use  of  35-  instead  of  16-mm  film,  would 
improve  considerably  the  reproductive  qual- 
ity of  televised  motion  pictures,  according 
to  James  Gordon,  ASC,  (20th  Century-Fox) 
in  a  paper  presented  to  the  American  So- 
ciety of  Cinematographers  Tv  Research 
Committee. 

The  standard  projection  print  has  a  high 
contrast  and  wide  brightness  range  neces- 
sary for  the  theatre,  which  is  more  than  the 
Tv  transmitter  can  accommodate.  Attempted 
adjustment  results  in  empty  shadows  and 
monotonous  high  lights  on  the  Tv  receiver. 
In  addition,  the  regular  projection  print  is 
not    a    perfect    reproducer    of    the    negative 


New  RCA  Tv  Tube  Plant  in  Indiana 

Work  has  begun  on  the  new  RCA  plant 
in  Marion,  Indiana,  in  which  100,000 
square  feet  of  space  will  be  added  to  the 
160,000  square  feet  RCA  already  has  in 
Marion  for  the  manufacture  of  16-inch, 
direct-view  metal  picture  tubes  for  Tv. 
The  new  tube  differs  radically  from  pre- 
vious Tv  tubes  in  that  it  uses  a  metal 
cone  or  center  section  instead  of  an  all- 
glass  envelope. 


IA     ELECTIONS 


LOCAL  165,  HOLLYWOOD,  CALIF. 

Walter  McCormick,  pres.;  Howard  Edgar, 
vice-pres.  (both  elected  unanimously)  ;  Rich- 
ard Hennley,  sec.-treas.;  Jas.  J.  Eddy,  bus. 
rep.;  Frank  Chaney,  Paul  R.  Cramer,  Rich- 
ard B.  Frisbie,  Daniel  F.  Haworth,  Harold 
Masser,  board  dir.;  James  Brigham,  Wm. 
E.  Hunger,  trustees;  Leo  S.  Moore,  C.  W. 
(Pat)  Offer,  Harold  G.  Swanson,  exam, 
board;  Jas.  J.  Eddy,  Chas.  Groman,  Richard 
Hennley,  Walter  R.  McCormick,  del.  Central 
Labor  Union;  Jas.  J.  Eddy,  del.  Calif.  State 
Fed.  of  Labor. 

LOCAL  316,  MIAMI,  FLA. 

Bob  Lewis,  pres.;  Wen.  Thaggard,  vice- 
pres.;  Frank  Raufer,  rec.-sec;  Frank  Lewis, 
cor. -sec;  Wm.  Reardon,  fin.-sec;  George  E. 
Raywood,  bus.  rep.;  Harry  Raywood,  sgt.-at- 
arms;  Jack  Shafer,  E.  E.  French,  Joe  Corn- 
phell,  W.  S.  Roberts,  exec,  board;  Bruce 
Burnell,  M.  Padula,  D.  Armstrong,  trustees. 

LOCAL  433,  ROCK  ISLAND,  ILL. 

Edward  Short,  pres.;  Mark  M.  Maston, 
vice-pres.;  Fred  Parker,  rec.-sec;  Warren 
Castle,  fin.-sec;  Fred  Parker,  bus.  rep.; 
Lloyd  Burrs,  treas.;  F.  E.  Wright,  trustee 
(3  years)  ;  Lloyd  Burrs,  exec,  board;  A.  W. 
Young,  del.  Iowa  State  Ass'n;  Edward  Short, 
del.  Illinois  State  Ass'n. 

LOCAL  486,   HARTFORD,  CONN. 

L.  H.  Albee,  pres.;  Gus  Soderburg,  vice- 
pres.;  Donald  MacDonald,  cor-sec;  Pete 
Di  Carli,  sec.-treas.;  Charles  North,  bus. 
rep.;  Harry  Avery,  sgt.-at-arms;  Tom  Har- 
ries, Frank  Panton,  exec,  board;  Tom  Pierce, 
trustee. 

LOCAL  571,  PORTSMOUTH,  OHIO 

W.  H.  De  Lotel,  pres. ;  C.  F.  Etzkorn,  vice- 
pres;  Roy  W.  Reeg,  rec.-sec;  E.  S.  Gahm, 
fin.-sec;  O.  H.  Osborne,  cor. -sec;  C.  F.  Etz- 
korn, bus.  rep.;  R.  Osborne,  sgt.-at-arms. 


Mass-Produce  Tape  Records 

The  final  technical  obstacle  in  the 
way  of  mass  production  of  recorded 
music  on  tape  has  now  been  overcome. 
A  machine  has  been  perfected  by  Minne- 
sota Mining  and  Mfg.  Co.,  St.  Paul,  that 
can  simultaneously  reproduce  48  hour- 
long  tape  recordings  indistinguishable 
from  the  master  transcription  in  one 
hour. 

These  pre-yecorded  reels  of  tape  will  be 
designed  to  compete  with  disc  records 
for  use  in  the  home,  in  broadcasting,  in 
schools  and  theatres.  Since  many  sound 
engineers  contend  that  magnetic  sound 
tape  has  better  fidelity  than  any  other 
known  sound  recording  medium,  it  is  to 
be  expected  that  recorded  music  on  tape 
may  enjoy  a  competitive  advantage  over 
disc  recordings,  whether  of  the  78,  45, 
or  33  1/3  r.p.m.  variety. 

Single  or  Double  Tracks 

Tape  can  be  recorded  with  a  single 
magnetic  pattern  in  the  center,  or  with 
a  double  pattern  of  two  magnetic  paths 
side-by-side  on  the  tape.  One  path  plays 
as  the  reel  unwinds  forward,  the  other 
path  functioning  when  the  tape  reverses, 
which  is  accomplished  automatically  in 
a  fraction  of  a  second.  The  double  pat- 
tern affords  twice  the  playing  time  with 
the  same  amount  of  tape. 

Reels  having  600  feet  of  tape,  double 
pattern,  and  a  playing  speed  of  3% 
inches  per  second  can  be  turned  out  at 
the  rate  of  48  per  hour,  each  reel  having 
a  full  hour's  playing  time.  Reels  with 
1,200  feet  of  tape,  double  pattern,  and 
a  playing  speed  of  7V2  inches  per  second 
can  be  turned  out  at  the  rate  of  32  per 
hour,  each  reel  having  one  hour  of  trans- 
cribed material. 


New  Lens  Measuring  Method 

A  new  degree  of  realism  in  television, 
motion  pictures  and  still  photography 
may  result  from  a  new  method  of  meas- 
uring contrast  characteristics  of  both 
optical  and  electrical  lenses  which  was 
described  recently  by  Otto  H.  Schade, 
advance  development  engineer  for  RCA. 
It  is  also  applicable  to  contrast  measure- 
ments for  different  types  of  photographic 
film  and  television  screen  materials. 

Employing  what  is  essentially  a  Tv 
pickup  and  reproduction  system,  this 
method  provides  the  optical  and  photo- 
graphic industries,  as  well  as  the  Tv 
field,  with  the  first  known  practical 
method  of  analyzing  and  rating  the  abil- 
ity of  various  types  of  lenses  to  show  pic- 
ture detail. 

For  industries  developing  or  using 
image-forming  devices,  this  method 
means  the  end  of  guesswork  and,  for  the 
first  time,  permits  objective  selection  of 
lenses  that  will  produce  the  best  results 
in  various  types  of  systems.   Data  on  the 


24 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


imaging  power  of  the  human  eye  have 
been  incorporated  in  the  procedure  for 
plotting  the  overall  response  of  lenses 
and  other  elements,  so  that  the  practical 
value  of  improvements  in  picture  quality 
can  be  determined  in  terms  of  the  observ- 
er's ability  to  detect  them. 

Expanded  Power  of  Resolution 

The  theoretical  values  by  which  lenses 
have  been  rated  heretofore,  Mr.  Schade 
explained,  are  based  on  their  limiting  or 
highest  power  of  resolution — that  is,  the 
greatest  number  of  lines  of  picture  detail 
per  mm  which  they  can  focus  on  film  or 
viewing  screen. 

However,  useful  resolutions  for  photog- 
raphy and  television  are  limited,  respec- 
tively, by  the  response  of  photographic 
film  and  the  width  of  Tv  frequency  chan- 
nels. To  improve  picture  detail  within 
these  limitations,  the  research  engineer 
in  these  fields  must  strive  for  sharper 
contrast  of  light  and  dark  picture  ele- 
ments within  lower  ranges  of  resolution — 
about  50  lines  per  mm  in  photography, 
and  one-fifth  as  many  lines  in  Tv. 

The  system  developed  by  Mr.  Schade 
affords  the  first  practical  means  of  de- 
termining the  contrast  response  of  lenses 
in  these  ranges,  or  in  any  specified  range 
from  zero  to  the  limiting  resolution. 


H.  P.  Niemann  Heads  Hertner; 
C.  Dash  Ends  30- Year  Span 

H.  P.  Niemann  has  been  elected  president 
and  a  director  of  The  Hertner  Electric  Co. 
He  has  served  as  vice-president  and  general 
manager    of    this    Cleveland    manufacturing 


H.  P.  Niemann, 

recently  named 

president  of 

Hertner  Electric  Co. 


plant  for  the  past  two  years.  He  previously 
was  executive  head  of  The  Askania  Regula- 
tor Co.  of  Chicago,  which,  like  the  Hertner 
company,  is  a  General  Precision  Equipment 
Corp.   subsidiary. 

Niemann  succeeds  C.  C.  Dash,  who  has 
retired  after  30  years  association  with  Hert- 
ner. H.  P.  Sherer,  who  has  been  serving 
as  vice-president  and  chief  engineer,  has 
recently  been  elected  a  director. 

Operating  since  1901,  the  Hertner  plant 
manufactures  a-c  and  d-c  motors  and  gener- 
ators, battery  chargers,  and  motor  generator 
sets,  with  the  Transverter  being  made  espe- 
cially for  use  in  the  motion  picture  field. 


Ampro's  16-mm  Planning  Service 

To  answer  important  questions  relative  to 
the  proper  use  of  16-mm  high-intensity  arc 
projectors,  Ampro  Corp.  has  announced  a 
new  planning  and  consultation  service.    Free 


of  charge  for  the  asking,  this  Ampro  service 
will  advise  on  such  things  as  audience  size 
and  seating  arrangements,  projection  throw, 
screen  size,  equipment  layout,  sound  hook- 
up, and  many  other  factors  which  contribute 
to  efficient  16-mm  performance. 

A  brochure  on  16-mm  arc  projection  may 
be  had  by  writing  Ampro  at  2835  N.  Western 
Ave.,  Chicago,  18. 


286    Drive-ln    Spots   Already   Open 

Reliable  estimates  indicate  that  the  Easter 
weekend  saw  the  opening  for  the  season  of 
286  drive-in  theatres,  while  about  325  others 
have  fixed  Memorial  Day  for  their  openings. 


New  Wenzel  Projector  Base 

Designed  especially  for  drive-in  theatres, 
a  new  base  (WB-600)  has  been  produced 
by  Wenzel  Projector  Co.  This  base  permits 
an  up-tilt  angle  of  25  degrees  and  a  down- 
tilt  angle  of  28   degrees. 

The  base,  made  in  two  sections  to  facili- 
tate handling,  weighs  about  350  pounds. 
On  the  front  is  a  large  shelf  for  tools,  car- 
bons, etc.  The  center  of  gravity  is  kept 
low  and  assures  practically  complete  absence 
of  vibration.  The  lamp  sliding  carriage  is 
cast  aluminum  and  is  accurately  machined 
so  as  to  accommodate  any  present  standard 
arc  lamp. 


IMPART 


TO  YOUR 


PRESENTATIONS 


THE  STRONG  TROUPER 


A.  C.  CARBON  ARC  SPOTLIGHT 


;: 


for  theatres,  auditoriums  and  night  clubs  where  the 


jth  of  tl 


feet. 


Produces  a  snow  white  uniformly  illuminated 
spot,  with  crisp  edges,  far  surpassing  in  bril- 
liancy any  incandescent  or  vertical  arc  type 
spotlight,  and  actually  equalling  many  large 
theatre  type  spotlights.  Supplies  a  sparkle  to 
presentations  obtainable  only  with  high  in- 
tensity arcs. 
Easily  operated. 

A  silvered  glass  reflector  collects  the  illumina- 
tion from  the  source  and  directs  it  to  a  cir- 
cular aperture,  from  where  it  is  projected  to 
the  stage  by  means  of  a  two-element  variable 
focal  length  lens  system. 
At  60  feet  the  size  of  the  spot  is  variable 
from  a  30-inch  "head  spot"  to  a  33-foot 
"flood". 

Draws  only  10  amperes  from  any  110-volt  A.C. 
convenience  outlet.  A  highly  efficient,  adjust- 
able, self-regulating  transformer  which  is  an 
integral  part  of  the  spotlight  base  reduces  the 


current  supply   to  a    low  arc  voltage,  for   the 
first  time  making  possible  a  high  intensity  arc 
■  spotlight   without    the    use    of    heavy    rotating 
equipment. 

The  carbons  are  fed  automatically  by  an  elec- 
tric motor  which  maintains  a  constant  arc 
gap.  This  results  in  a  steady  light,  free  from 
hiss  or  flicker. 

A  trim  of  carbon  consists  of  two  6mm  x  7" 
heavy  copper  coated  high  intensity  carbons 
with  a  burning  time  of  one  hour  and  twenty 
minutes  at  21  volts  and  45  amperes  arc  cur- 
rent. 

A  horizontal  masking  control  can  be  angled 
at  45  degrees  in  each  direction  from  hori- 
zontal. 

The  color  boomerang  contains  six  slides  and 
an  ultraviolet  filter  holder. 
Mounted  on   casters.     Easily  disassembled   for 
shipment. 


SOLD  BY  INDEPENDENT  THEATRE  SUPPLY  DEALERS. 
Use  the  coupon  to  obtain  further  details,  prices  and  name  of  your  nearest  dealer. 


THE 

STRONG 

ELECTRIC  CORP. 

"The  World's  Largest  Manu 
icturer  of  Projection 
Arc  Lamps" 


Please  send  free  literature,  prices  and  name  of  the 
nearest  dealer  in  Strong  Spotlights. 


NAME 


COMPANY     

STREET    

CITY   and    STATE 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


25 


British  35-mm  Film  Standard 
in  Accord  with  U.  S.  Specs 

Specifications  for  35-mm  theatre  re- 
lease prints  which  will  constitute  a 
British  Standard  have  been  announced 
by  the  British  Kinematograph  Society 
(B.S.  1492-1948).  The  Standard  details 
requirements  for  reels,  cue  marks,  lead- 
ers and  trailers,  and  also  makes  recom- 
mendations on  the  protection  of  prints 
and  the  avoidance  of  emulsion  pickup. 

The  specification  is  substantially  in 
accord  with  American  standards,  except 
that  an  additional  sound  synchronizing 
mark  is  provided  for  use  when  reduction 


prints  are  made  to  16  mm:  this  addi- 
tional mark  takes  the  form  of  a  circle 
imposed  upon  a  transverse  line,  26 
frames  from  the  picture  start-mark.  The 
maximum  length  of  reel  is  fixed  at 
2,050  ft. 

Wood  Reel  Cores  Still  Used 

It  is  recommended  that  a  protective 
band  (e.g.,  of  tough  paper)  be  provided 
around  every  reel,  and  where  transit 
spools  (reels)  are  not  provided,  that  a 
hardwood  core  shall  be  used.  Edge- 
waxing  or  other  treatment  to  prevent  in- 
crustation of  gelatine  is  also  recom- 
mended. 


fsjsaJ 


HERE'S  THE  INCREASED  LIGHT 

YOU'VE  WANTED  FOR 

DRIVE-IN  &  LARGE 
INDOOR  SCREENS 


m 


I      ..  ...  X}<7*/;% 


^ 


Operating  at  85  amperes,  the  Motiograph-Hall  produces  19,000  lumens — more  light 
than  condenser-type  high  intensity  lamps  operating  at  more  than  twice  this  am- 
perage. 

A  rotating  positive  carbon  (an  exclusive  feature)  permits  even  burning  of  the 
carbons  and  a  proper  crater  form. 

Due  to  the  extremely  high  intrinsic  brilliancy  of  the  Motiograph-Hall  arc,  the 
total  light  output  contains  a  much  larger  percentage  of  visible  light,  making  unnec- 
essary the  use  of  a  filter  which  would  reduce  the  amount  of  visible  light  passed. 

The  automatic  focus  control,  another  exclusive  feature,  constantly  holds  the 
crater  of  the  positive  carbon  at  the  exact  focal  point  of  the  mirror,  preventing 
variations  in  the  character  of  the  light  at  the  screen. 

The  Motiograph-Hall  lamp  is  designed  to  use  9-mm.  or  11 -mm.  high  intensity 
positive  carbons  and  5/16"  negative  carbons,  the  cost  of  which  is  about  one-third 
that  of  the  cost  of  the  larger  carbons  used  in  condenser-type  lamps  operating  in 
the  140-180  ampere  range. 

Other  Motiograph  products  include  Motiograph  1  K.W.  and 
46-ampere  high  intensity  arc  lamps,  Motiograph  projectors, 
indoor  and  outdoor  sound  systems,  generators  and  rectifiers, 
in-car  speaker  equipment  and  junction  boxes,  ramp  switching 
panels  for  drive-ins,  turntables,  etc. 

Literature  and  Complete  Information  May  be  Obtained  from 


New  Soundhead  by  Wenzel 

A  new  soundhead,  the  WSH-3,  is  now  in 
production  at  Wenzel  Projector  Co.  The 
head  is  supplied  complete  with  a  single- 
phase,  50-60  cycle  motor  operation  on  110 
volts,  and  the  head  is  driven  by  two  sturdy 
V  belts.     The  photocell  mounting  has  been 


monoGRAPH,  inc., 


4431     W.     LAKE     ST.,     CHICAGO     24, 


Interior    view    of    redesigned    Wenzel    sound- 
head, WSH-3,  now  being  distributed. 

redesigned,  and  it  is  no  longer  necessary  to 
purchase  a  mounting  tube,  the  cell  being 
connected  by  means  of  two  binding  posts. 
The  cell  can  be  changed  within  a  few  sec- 
onds time. 

The  motor  table  is  attached  directly  to  the 
center  frame  of  the  head  and  may  be  moved 
easily  to  insure  belt  tension  at  all  times. 
The  exciter  lamp  is  of  the  prefocus  type  and 
is  instantly  adjustable  without  the  use  of 
tools. 

An  attractive  illustrated  brochure  relating 
to  this  soundhead  is  available:  address  Wen- 
zel at  2505  So.  State  St.,  Chicago,  111. 

LENS    DESIGN,   MANUFACTURE 

(Continued  from  page  22) 

to  have  a  maximum  transmission  and  mini- 
mum reflectivity  in  the  apple-green  part  of 
the  spectrum  at  about  5,500A.  Away  from 
that  minimum  position,  you  do  get  a  certain 
amount  of  light  reflected. 

Q.  If  you  coated  for  a  particular  wave- 
length, what  percentage  gain  would  you  ex- 
pect for  a  particular  monochromatic  light? 

A.  There  is  a  condition  that  the  refractive 
index  of  the  film  should  be  the  square  root 
of  the  refractive  index  of  the  glass.  It  is 
not  possible  to  obtain  that  condition  pre- 
cisely, because  there  are  not  many  minerals 
of  a  suitable  type  for  evaporating  on  to  the 
glass  surface.  We  have  to  use  magnesium 
fluoride. 

Q.  How  does  the  reflectivity  curve  con- 
tinue into  the  infra-red?  At  12.000A  would 
there  be  any  improvement  with  coated 
lenses? 

A.  Yes,  there  would  still  be  a  considerable 
improvement.  It  is  possible  by  evaporating 
successive  layers  of  different  minerals  to 
attain  an  achromatic  effect. 

Light-Collecting   Facilities   Lagging 

Q.  Is  it  likely  that  faster  aperture  lenses 
than  are  now  available  will  come  into  use 
soon?  If  that  is  so,  it  will  mean  re-designing 
the  collecting  system  of  the  arc  lamp. 

A.  The  case  is  really  that  the  light  collect- 
ing end  of  the  system  is  lagging  behind  the 
projection  lens.  The  wider  the  angle  of  pick- 
up the  greater  the  trouble  with  heating. 

Q.   Regarding  the  desirability  of  matching 


26 


INTERNATIONAL  PROJECTIONIST 


April  1949 


apertures  from  the  mirror  to  the  lens,  recent 
papers  in  American  journals  have  suggested 
that  the  illumination  at  the  edges  of  the  pic- 
ture is  improved  if  the  projection  lens  is  of 
wider  aperture  than  the  mirror.  What  are 
Mr.  Anstis's  views  on  this  subject? 

A.  I  think  that  one  American  writer  was 
endeavoring  rather  to  point  out  that  certain 
American  projection  lenses  gave  some  cutoff 
of  light  due  to  their  improper  design.  You 
have  that  case  in  some  American  projectors 
using  F:\.9  lenses  giving  only  F:1.9  at  the 
center.  If  you  are  free  to  increase  the  diam- 
eter, you  will  get  F-.1.9  at  the  margin.  (See 
Editor's  Note  following  this  discussion) 

Q.  What  do  you  consider  is  a  natural  basis 
for  the  calibration  of  lenses  in  transmission 
values? 

A.  The  old  basis  was  the  relation  of  the 
diameter  of  the  lens  to  the  focal  length. 
This  gave  the  F-value.  That  does  not  take 
into  consideration  the  transmission  of  the 
lens.  If  one  imagines  a  lens  of  100%  effi- 
ciency, that  is  the  theoretical  basis  of  the 
T-scale. 

Q.  Am  I  not  right  in  thinking  that  the 
coating  is  not  permanent?  The  F-number 
of  a  lens  is  permanent,  but  the  T-scale  would 
vary  in  time. 

A.  Modern  coatings  are  hard  and  sub- 
stantial. Over  a  number  of  years  the  trans- 
mission would  not  vary  appreciably. 

Q.  How  is  an  aspherical  surface  produced? 

A.  They  cannot  be  produced  in  the  man- 
ner as  for  ordinary  lens  surfaces.  The  grind- 
ing and  polishing  tools  when  producing 
spherical  surfaces  oscillate  in  a  free  motion 
over  the  top  of  the  lens.  In  making  aspheri- 
cal surfaces,  one  has  usually  to  depend  on 
some  kind  of  a  formula  or  link  mechanism 
for  producing  the  curvature  mathematically. 

[Editor's  Note:  This  is  undoubtedly  a 
reference  to  IP  in  which  have  appeared  sev- 
eral penetrating  articles  on  the  topic  of 
"matched"  optics,  notably  those  by  Dr.  John 
L.  Maultbetsch  (Kollmorgen  Optical  Co.), 
and  by  R.  H.  Mitchell,  regular  contributor 
to  IP.] 


SMPE  CONVENTION   ROUNDUP 

{Continued  from  page  17) 

and  the  conclusion  is  reached  that  a  sub- 
stantial increase  in  screen  illumination  may 
be  obtained  by  these  methods,  such  increase 
being  from  30  to  60%  beyond  the  present 
safe  maximum. 

ELECTRONIC    PROJECTION    LAMP 

J.  K.  Elderkin 

Forest  Electronic  Company 

A  major  problem  in  the  operation  of  arc 
lamps  for  projection  is  the  feeding  of  the 
two  carbons  as  they  burn.  In  general,  it  is 
held,  present  motor-driven  arc  feed  mechan- 
isms do  not  maintain  the  crater  in  correct 
focus  for  any  considerable  time  and  do  not 
maintain  a  constant  arc  length,  thus  re- 
quiring almost  constant  attention  by  the 
projectionist. 

A  new  lamp  mechanism  with  completely 
separate  feeding  mechanisms  for  each  of 
the  carbons  has  been  developed.  Feeding 
rates  of  each  carbon  are  controlled  independ- 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


sm»i:i;-s\\ii»m  i: 


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SEALED 
HERMETICALLY 


.  ONE-PIECE 
MOUNT 


ANODIZED 
FINISH 


COATED 
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DOES  THE  F/1.9  SUPER-SNAPLITE  HAVE  A  TRUE  SPEED 
OF  F/1.9? 

Yes — in  all  sizes  from  2"  up  through  4%".  The 
5"  size  has  a  speed  of  f/2.0. 

WHY  DOES  THE  5"  SUPER-SNAPLITE  HAVE  A  DIFFERENT 
SPEED  FROM  THE  SHORTER  FOCAL  LENGTHS? 

Because  of  the  limited  space  in  the  projector.  In 
other  words,  a  5"  lens  with  a  speed  of  f/1.9 
would  not  fit  into  present  projectors  because  of 
the  large  diameter  needed  for  the  lens  barrel. 

DOES  THE  SUPER-SNAPLITE  LENS  HAVE  DIAPHRAGMS? 
No — the  full  aperture  is  utilized  in  all  focal 
lengths. 

DOES  A  FAST  LENS  ELIMINATE  THE  "HOT  SPOT"? 

To  a  very  large  extent  The  faster  the  lens,  and 
the  higher  its  quality,  the  more  uniform  the 
screen  illumination  will  be. 

IS  THE  "HOT  SPOT"  WORSE  WITH  SHORT  FOCAL  LENGTH 
LENSES? 

Usually.  The  falling  off  in  illumination  at  the 
corners  can  be  quite  severe  with  poor  lenses. 
This  problem  was  given  full  consideration  when 
Super-Snaplite  lenses  were  designed.  Even  in 
the  shorter  focal  lengths,  they  give  re- 
markably even  screen  illumination. 


"You  Get  the  Most  Uniform  Light  with  Super-Snaplite" 

i:om,a\oim;1Tn    ,      @t 

2  Franklin  Avenue  t        ^»^~rJ^^m/  ......  >.  -«-..-. 

Brooklyn  11,  New  York         \^/^U/COl     CORPORATION 


27 


ently  and  with  extreme  accuracy  by  employ- 
ing a  nearly  constant  speed  a-c  motor  as  the 
driving  means  for  each  mechanism  and  a  sep- 
arate electronic  pulse  generator  for  each  feed 
motor.  Any  desired  feeding  speed  may  be 
obtained  simply  by  adjusting  the  number 
of  pulses  per  minute  fed  to  the  motor. 

To  accomplish  these  results  a  very  accu- 
rate electronic  impulse  generator  energized 
from  the  110-volt  illuminating  current  supply 
has  been  devised.  The  paper  also  discusses 
the  Suprex,  simplified  high-intensity,  high- 
intensity  and  electronic  type  arcs. 

THE  SOCIAL  IMPACT  OF  TELEVISION 
Ralph  B.  Austrian 

In    the    New    York    Metropolitan    area,    a 


14%%  saturation  point  in  regard  to  homes 
with  Tv  has  already  been  reached,  and  the 
outlook  in  this  area  is  for  a  saturation 
point  of  between  90  and  100%  in  no  more 
than  five  years,  barring  external  interfer- 
ence. An  important  need  today  is  the  pro- 
duction of  a  receiver  to  retail  complete  at 
between  $100  and  $125. 

Judging  by  the  effect  of  sound  on  silent 
motion  picture  theatres,  network  radio,  as 
it  exists  today,  is  about  to  enter  the  first 
stages  of  a  rapid  decline.  A  recent  survey 
shows  a  decline  in  motion  picture  atten- 
dance among  Tv  set  owners  ranging1  from 
23  to  36%.  Similarly,  radio  listening  among 
these  people  has  declined  drastically. 

Tv  has  already  been  reported  as  cutting 
into  motion   picture  attendance   at  the  rate 


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of  about  500,000  admissions  per  week,  a  loss, 
even  today,,  of  some  $243,000  each  week  at 
the  box-office.  Even  this  seemingly  small 
figure  is  of  extreme  importance.  The  mo- 
tion picture  industry  cannot  preserve  its 
present  state  of  prosperity  by  doing  nothing. 
Tv  is  an  ideal  medium  for  the  advertising  of 
motion  pictures.  It  is  imperative  that  the 
engineers  of  the  motion  picture  industry 
turn  ever  increasing  attention  to  the  techni- 
cal phases  of  Tv. 

16-MM    FILM   COLOR   COMPENSATION 

O.   Ken   Kendall 

National  Film  Board,  Canada 

Second-generation  color  duplicates  in  16- 
mm  are  so  noted  for  problems  of  contrast 
and  color  fidelity  as  to  be  responsible  for  a 
widespread  practice  of  printing  from  the 
original.  Release  printing  from  originals 
having  the  required  corrections  would  prob- 
ably involve  too  many  operations  to  be 
economically  feasible.  Techniques  and 
equipment  have  therefore  been  devised  for 
making  at  reasonable  cost  a  key  film  from 
which  release  prints  may  be  made. 

These  key  films  seek  to  require  conventional 
timing  to  maintain  general  color-casts  of 
significant  images  on  a  scene-to-scene  basis, 
to  retain  transmission  brightness  relative  to 
other  hues  in  the  same  frame,  retain  detail 
in  under-exposed  shadows  and  limit  the  in- 
crease in  contrast  that  may  occur  with  each 
generation  of  printing  from  reversals.  A 
chart  is  given  showing  various  settings  for 
blue,  green  and  red  in  the  printer  which 
compensate  for  different  faults  in  the 
original. 

Test  duplicates  made  from  key  masters  in 
the  manner  described  have  demonstrated  the 
same  contrast  as  the  original,  less  color  dis- 
tortion than  the  original  considered  on  a 
scene-to-scene  basis,  superior  color  than  an 
original  over-exposed  throughout  a  shot,  and 
more  natural  color  for  the  shadow  sides  of 
faces,  than  in  conventional  first-generation 
prints. 

APPLICATION    OF   MAGNETIC   RECORDING 

TO   MOTION    PICTURE  TECHNIQUES 

J.  G.  Frayne  and  H.  Wolfe 

Western  Electric  Company 

The  background  of  magnetic  recording  is 
discussed,  starting  with  the  experiments  of 
Poulsen  in  1898.  In  1941  the  work  of  Bell 
Telephone  Labs  enabled  production  of  the 
first  high-quality  magnetic  recorder  available 
to  the  public. 

A  d-c  bias  applied  to  magnetic  recording 
makes  it  possible  to  record  over  a  large  por- 
tion of  the  magnetization  curve  without  ap- 
preciable distortion.  However,  d-c  bias  does 
not  give  sufficiently  outstanding  quality  nor 
a  sufficiently  good  signal-to-noise  ratio.  A-c 
bias  has,  therefore,  been  generally  used  in 
contemporary  magnetic  recording  systems. 

The  Germans,  during  the  war,  developed 
the  Magnetophon,  which  used  plastic  tape 
with  an  impregnated  or  coated  layer  of  a 
magnetic  iron  oxide  powder  and  gave 
quality  superior  to  that  of  all  previous  mag- 
netic recorders.  The  experience  gained  from 
study  of  this  equipment  made  it  apparent 
that  magnetic  recording  could  be  adapted  to 


28 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


motion  picture  recording  at  the  relatively 
low  speed  of  18  inches  per  second. 

It  was  necessary  that  frequency  response, 
signal-to-noise  ratio,  and  flutter  performance 
he  at  least  comparable  to  recordings  made 
by  optical  means.  This  has  been  accom- 
plished in  the  new  Western  Electric  method. 
The  magnetic  recorder  utilizes  the  RA-1231 
photographic  film  recorder  as  a  basis,  using 
a  number  of  added  or  substituted  conversion 
parts.  The  recorder  may  also  be  used  for 
photographic  recording. 

The  method  of  installing  the  magnetic 
parts  is  described.  Recordings  are  made  on 
a  250-mil  wide  track  0.450  inch  from  the 
edge  of  the  film.  If  desired,  the  recorder 
itself  can  be  employed  as  a  reproducer.  The 
design  of  the  magnetic  heads  is  described, 
as  are  the  recording  transmission  system  and 
controls  and  the  use  of  pre-  and  post-equali- 
zation. Flutter  measurements  indicate  total 
flutter  to  be  about  0.1%. 

The  RA-1251B  rerecorder  has  similarly 
been  adapted  to  magnetic  operation.  This 
equipment  may  be  used  for  both  recording 
and  playback.  The  RA-1435  theatre  type 
sound  reproducer  has  also  been  adapted  to 
magnetic  operation  to  provide  review  room 
facilities. 

The  conclusion  is  made  that  recordings  of 
music  and  dialogue  made  on  this  system  show 
an  excellence  of  quality  unsurpassed  in  any 
previously  known   recording  system. 

16-MM  SOUNDFILM  PRACTICES 

John  A.  Maurer 

J.  A.  Maurer,  Inc. 

Numerous  improvements  in  the  technique 
of  producing  16-mm  soundfilms  and  in  repro- 
ducing the  sound  tracks  make  possible  today 
a  substantially  higher  quality  than  is  gen- 
erally obtained  commercially  at  present. 
Recognition  of  this  fact,  coupled  with  a  de- 
mand by  the  Tv  industry  for  16-mm  sound 
of  consistently  high  quality,  has  led  to  a 
proposal  that  the  industry  adopt  a  standard 
16-mm  reproducing  characteristic. 

This  proposal,  it  is  believed,  would  make 
it  possible  for  16-mm  sound  to  be  of  sub- 
stantially the  same  quality  as  35-mm  sound 
as  commonly  heard  in   theatres. 

This  paper  presents  an  analysis  in  engi- 
neering terms  of  substantially  all  the  factors 
known  to  be  measurable  or  calculable  which 
determine  what  quality  is  possible  with  16- 
mm  sound  films,  assuming  that  cost  of  repro- 
ducing equipment  is  not  a  primary  limiting 
factor.  While  a  wide  frequency  range  is  de- 
sirable, noise  and  distortion  must  be  taken 
into  account  in  determining  how  wide  a  fre- 
quency range  it  is  practical  to  use. 

Various  factors  in  recorder  design  are 
discussed  from  the  standpoint  of  their  con- 
tributions to  overall  noise  and  distortion, 
and  a  similar  analysis  is  made  of  the  various 
elements  in  the  sound  reproducer.  Different 
sy-tems  of  recording,  such  as  neg'ative-posi- 
tive  variable  area  and  variable  density,  and 
direct  positives,  are  compared.  The  effect  of 
film  laboratory  processes  on  overall  quality 
is  discussed  in  considerable  detail. 

16-mm  Film  Now  Threatens  35-mm 

The  conclusion  is  reached  that  at  the  pres- 
ent lime  the  well-accepted  standard  of  35- 
mm   theatre  sound   quality  can   be   equaled. 


using  16-mm  films  and  equipment,  with  rela- 
tively little  difficulty,  and  that  where  a 
higher  standard  of  quality  is  required,  as 
may  be  the  case  in  Tv  film  production,  it 
can  be  obtained  if  more  than  ordinary  care 
is  exercised  in  the  work  of  the  film  labora- 
tory. 

The  various  points  brought  out  in  the  dis- 
cussion were  illustrated  by  the  use  of  16-mm 
films  re-recorded  from  an  original  master 
record  on  magnetic  tape,  which  includes  the 
entire  audible  frequency  spectrum  and  has 
very  low  distortion. 

Samples  of  speech,  music,  and  sound  ef- 
fects from  this  high-quality  original  are  re- 
recorded to  film  using  the  various  techniques 
discussed,  and  these  records  are  reproduced 
in  such  a  way  as  to  simulate  the  effect  of 
different  reproducing  systems  and  charac- 
teristics by  the  use  of  a,  high  quality  16-mm 
playback  and  electrical  filters  which  modify 
its  characteristics  in  known  ways. 

WATER-COOLED,  HIGH-PRESSURE  MER- 
CURY   DISCHARGE   LAMP    FOR   D-C 
W.   Elenbaas  and   E.  W.  van   Heuven 
Philips   Lamp   Works,   Holland 

A  water-cooled  high  pressure  mercury 
lamp  operated  on  d-c  is  described,  which 
has  been  in  use  in  motion  picture  projection 
for  many  years  and  which  is  a  powerful  light 
source.  The  lamp  has  a  bore  of  somewhat 
less  than  2  mm  and  an  arc  length  of  12% 
mm.  It  may  be  loaded  continuously  at 
1000   watts   and  has   a   brilliancy  of  50,000 


stilb  in  the  axis.  With  a  lamp  of  double 
length  consuming  2  Kw  the  illumination 
level  may  be  increased  considerably. 

HALF    A    MILLION    STATIONARY    IMAGES 

PER  SECOND  WITH  REFOCUSED  REVOLVING 

BEAMS 

C.  D.  Miller 

Battelle  Memorial  Institute 

A  motion  picture  camera  has  been  devel- 
oped in  the  laboratories  of  the  National  Ad- 
visory Committee  for  Aeronautics  which  has 
made  photographs  of  combustion  phenomena 
in  an  engine  cylinder  at  500,000  frames  per 
second. 

In  this  camera  the  film  remains  stationary 
while  the  beam  from  a  rotating  mirror  sweeps 
across  fixed  refocusing  lenses,  providing  an 
effect  similar  to  that  of  still  cameras  with 
high-speed  shutters  timed  to  open  at  slightly 
different  times. 

Recent   studies   show  that   knocking  com- 


Free  Pamphlet 

On  The  Care  Of  Your  Screen 
And  The 

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Method  Of  Resurfacing  Screens 

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THE  PROJECTIONIST 

No    matter   what    you    need 
in    the    way    of    equipment  and 
supplies  ...  no  matter  what 
the    hour   of   an    emergency 
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INTERNATIONAL  PROJECTIONIST     •     April  1949 


29 


bustion  in  an  engine  often  involves  detona- 
tion waves  traveling  more  than  a  mile  a  sec- 
ond. The  photographs  obtained  with  this 
camera  have  provided  valuable  new  informa- 
tion on   engine  knock.     It  is  believed   that 


DL 


u  re  a 


uaranlee 


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Precision  designed,  ruggedly 
constructed,  factory  "aged" 
and  thoroughly  tested  for 

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CONSTANT    POWER  SUPPLY 

LONG   LIFE 


Guaranteed  fori, 200 op- 
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at  their  proper  rating. 


ASK  YOUR   DEALER 
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GORDOS   CORPORATION 


86   SHIPMAN   STREET 


NEWARK  2,  N.  J. 


nuinRD  uiinnER 

Flutter  Suppressor  Wins 
ACADEMY   AWARD! 


redesign  of  the  camera  will  provide  improved 
definition,  and  the  camera  should  find  wide 
application  in  the  study  of  explosion  and 
detonation  phenomena,  shock  waves,  ballis- 
tics, rapid  stress  changes  in  mechanical 
parts  as  observed  by  photoelasticity,  and 
even  the  action  of  very  small  high  speed 
mechanism. 


PRECISE  LENS  CALIBRATION 

(Continued  from  page  15) 
standard  diaphragms  give  an  accurate 
indication  of  the  amount  of  light  trans- 
mitted. The  second  curve,  on  the  other 
hand,  will  not  in  general  be  a  straight 
line  unless  the  marked  F-numbers  are 
accurate  in  terms  of  light  transmission 
or  are  affected  by  a  constant  error. 

The  F-number  corresponding  to  a 
marked  F-number  is  then  obtained  by 
locating  the  point  on  the  first  curve  where 
the  scale  deflection  is  the  same  as  that 
for  the  given  F-number.  The  value  of 
the  abscissa  for  this  point  is  the  corre- 
sponding    ^-number.      An     approximate 


"'•I 


The  Academy  of  Motion  Picture  Arts  &  Sciences  recog- 
nized the  value  of  this  development  in  making  its  1947 
award  to  C.  C.  Davis  of  the  Western  Electric  Co. 

CENTURY  can  give  you  this  outstanding  improvement 
in  sound  reproduction   NOW. 


O 

o 
o 
o 
o 
o 
o 
o 


Tfce  Award- 
winning  Hydro 
Flutter  Suppressor 
as  used  in  the 
new  Century 
sound  reproducer. 


Improve 

ance    quality   in    your    theatre  —  see 

your  dealer  or  write  for  information. 

CENTURY  PROJECTOR  CORP 

New  York,  N.  Y. 


h   8° 


OBJECTIVES  OF  F:l  APERTURE  AND  GREATER      |   -< 

Edward  K.  Kaprelian  3   2 , 

Progress  during  the  past  60  years  has  2 
enabled  the  relative  aperture  of  a  well-cor-  I 
rected  objective  for  normal  field  of  view  to  ' 

be  increased  from  about  F:5  to  about  F:1.4. 
The  factors  involved  in  the  design  of  larg'e- 
aperture  objectives  and  some  of  the  general 
approaches  to  the  reduction  of  various 
aberrations  are  presented.  Both  refracting 
and  reflecting  systems  are  considered,  in- 
cluding objectives  having  spherical  and  as- 
pherical  surfaces  and  those  employing  the 
immersion  principle.  Applications,  testing, 
and  performance  of  extreme  aperture  objec- 
tives  are   discussed. 


1   1    1 

LENS  N0.5 

/ 

// 

172.7 

-f-4CM 

# 

0.76  TRANSMITTANCE 

/ 

// 

// 

16  0      22.6        32.0 


GEOMETRIC   F- NUMBER 


FIGURE  2 


Century  Sound  Reproducer 


measure  of  the  light  losses  within  the 
lens  may  be  obtained  directly  from  the 
lateral  displacement  of  the  two  curves. 

The  errors  in  marking  the  stop  num- 
bers of  the  lenses  under  study  were  also 
carefully  investigated,  with  particular 
attention  to  those  arising  from  errors  in 
focal  length  and  effective  aperture,  either 
separately  or  together.  It  was  found  that 
the  magnitude  of  these  errors  was  fre- 
quently as  great  as  the  difference  be- 
tween stop  openings  at  the  larger  F- 
numbers. 

Coordination  of  Data 

In  connection  with  this  phase  of  the 
investigation,  a  method  was  developed 
for  presenting  all  calibration  information 
on  a  single  graph  (Fig.  2).  The  inter- 
vals between  successive  stop  openings 
are  equal  and  can  be  taken  as  a  unit  on 
each  scale. 

The  marked  values  of  the  F-numbers 
(indicated  by  circles  on  the  graph)  and 
the  values  of  the  calibrated  F-numbers, 
or  F-numbers  (indicated  by  crosses),  are 
plotted  against  the  true  geometric  F- 
number  (the  quotient  of  measured 
equivalent  focal  length  and  measured 
effective  diameter  of  the  stop  opening). 
A  straight  line  is  drawn  through  the 
crosses,  and  a  dotted  diagonal  line  with 
unit  slope  is  also  drawn. 

If  there  are  no  errors  in  the  marked 
F-numbers — that  is,  if  the  indicated  F- 
number  equals  the  true  geometric  F-num- 
ber — all  the  circles  will  fall  on  the 
dotted  line.  On  the  other  hand,  if  the 
circles  do  not  fall  on  the  dotted  line,  the 
error  in  F-number  can  be  easily  esti- 
mated from  the  curve  as  a  fraction  of  the 
interval  between  stop  openings. 

All  of  the  crosses  would  also  fall,  on 
the  dotted  line  if  the  transmittance  were 
100%.  The  displacement  of  a  cross  from 
the  dotted  line  is  thus  a  measure  of  the 
transmittance  of  the  lens  at  that  stop 
opening.  If  the  crosses  fall  on  a  straight 
line  parallel  to  the  dotted  line,  the  cali- 
bration is  consistent  and  the  measure- 
ment of  the  true  geometric  F-number  is 
correct. 


30 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


THE  USE  OF  FILMS   IN  Tv 

(Continued  from  page  14) 
era  shutter  remains  open  for  exactly  two 
Tv  fields,  closes  for  exactly  x/2  field  while 
the  film  is  advanced,  then  opens  again 
for  the  exact  equivalent  of  two  more  Tv 
fields  (actually  %  plus  1  full  plus  % 
field ) .  It  then  closes  for  %  field  while 
the  film  is  advanced  a  second  time,  and 
again  opens  at  exactly  the  beginning  of 
the  next  field.  The  two  non-symmetrical 
cycles  are  then  repeated. 

One  serious  objection  to  the  mechani- 
cal shutter  for  Tv  picture  recording  lies 
in  the  need  for  perfect  synchronization 
between  the  motor  that  drives  the  shutter 
and  the  Tv  frame-rate  generator  which 
may  not  necessarily  operate  from  the 
same  60-cycle  a-c  current  power  line. 
The  shutter  action  is  critical  in  that  it 
must  rotate  with  extremely  low  flutter 
content,  since  minute  changes  in  angular 
velocity  will  result  in  banding,  the  effect 
of  over-  or  under-exposure  of  scanning 
lines  adjacent  to  the  cutoff  point. 

With  the  electronic  shutter  now  being 
used  with  some  installations,  this  prob- 
lem is  minimized  because  the  Tv  picture 
tube  is  electronically  blanked  or  turned 
off  at  the  end  of  each  525  lines  (one 
complete  Tv- frame  cycle)  and  is  not 
turned  on  again  until  the  film  has  been 
pulled  down  and  brought  to  rest.  Also, 
the  electronic  shutter  can  accommodate 
any  film-frame  rate  less  than  a  given 
maximum  determined  by  the  practical 
limitations  of  film-pulldown  time. 

Equipment  Choice:  16-  vs.  35-mm 

The  majority  of  Tv  film  recordings 
are  made  on  16-mm  rather  than  35-mm 
film.  The  major  reason  is  economic, 
since  the  cost  of  35-mm  film  is  some- 
what more  than  three  times  the  cost  of 
16-mm  per  unit  of  recording  time.  The 
current  quality  of  Tv  images,  which  un- 
doubtedly will  undergo  gradual  refine- 
ment, is  considered  to  be  roughly  equiva- 
lent to  16-mm  home  motion  pictures. 

No  marked  improvement,  however,  is 
to  be  had  by  recording  on  35-mm  rather 
than  16-mm  film  at  the  present  time. 
With  the  use  of  fine-grain,  high-resolu- 
tion, 16-mm-film  emulsions,  no  loss  of 
resolution  in  recording  the  Tv  image 
is  noticeable. 

Fire  regulations  covering  the  use  of 
35-mm  film,  which  apply  regardless  of 
whether  the  film  is  acetate  safety  base 
or  the  combustible  nitrate  base,  are  rig- 

Garver  Electric's  New  Indiana  Plant 

Garver  Electric  Co.,  manufacturers  of  pro- 
jection rectifiers  since  1915,  has  purchased 
a  new  factory  building  in  Union  City,  In- 
diana, which  will  provide  6500  square  feet 
of  working  space.  Many  improved  facilities, 
including  modern  test  equipment,  have  been 
added. 


orous.  The  cost  of  providing  space  that 
meets  these  regulations  is  extremely  high 
and  the  changes  needed  in  existing 
space  are  difficult  to  accomplish.  Six- 
teen-mm  films  are  available  only  in  ace- 
tate safety  base  which  is  classified  by 
the  Underwriters'  Laboratories  as  having 
a  safety  factor  slightly  higher  than  that 
of  newsprint.  The  use  of  16-mm  films, 
therefore,  is  not  restricted  by  fire  regu- 
lations. 

It  should  be  noted  that  in  New  York 
City  these  restrictions  apply  to  space  in 
which  equipment  capable  of  operating 
with  35-mm  film  is  installed,  so  in  order 
to  forestall  trouble,  all  equipment  should 
be  single-purpose,  16-mm  equipment 
rather  than  dual-purpose,  35-mm  or  16- 
mm  equipment. 

Another  factor  in  the  choice  of  16-mm 
film  is  the  high  cost  of  35-mm  projec- 
tion equipment.  Most  Tv  stations  are 
providing  projection  facilities  for  16-mm 
film  only  for  this  reason.  In  order  to 
service  these  stations  with  syndicated 
programs  photographed  from  the  picture 
tube,  16-mm  prints  will  be  needed. 

Emulsion  Spectral  Characteristics 

There  are  three  general  classifications 
of  film  emulsions  in  terms  of  their  spec- 
tral characteristics  and  they  can  be 
matched  to  the  phosphor  spectral  char- 


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for  18  years  and  consider  it  a 
'must'  for  proper  operation  of 
my  theatres." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


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For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reels. 
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THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reels. 

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WITH   ANY     LAMP      IN  ANY  SIZE     THEATRE     I 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


31 


dCteristic    of    the    Tv    picture    tube,    for 
greatest  actinic  efficiency. 

1.  Panchromatic  emulsions  are  most 
sensitive  in  the  range  from  the  ultraviolet 
(4000  angstrom  units)  through  the  red 
(7000  A).  The  spectral  response  of  these 


SAMUEL  ROSEN— Vice-President 
&  Treasurer,  Fabian  Theatres,  New 
York,  N.  Y. — says: 

"From   our  first   theatre  to 
now,  it  has  uninterruptedly 
been  RCA  Service." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


emulsions  corresponds  approximately  to 
that  of  the  eye  and  so  are  generally  used 
for  direct  photography; 

2.  Orthochromatic  emulsions  are 
sensitive  from  the  ultraviolet  through 
green  (5700  A)  and  are  used  in  direct 
photography  where  it  is  desirable  to  re- 
duce the  red  sensitivity; 

3.  "Ordinary,"  blue-sensitive  emul- 
sions, respond  to  the  ultraviolet  and  blue 
portions  of  the  light  spectrum.  This  type 
of  emulsion  is  used  in  coating  films  and 
papers  generally  employed  in  making 
positive  prints  from  negatives.  It  is  eco- 
nomical in  comparison  to  the  panchro- 
matic and  orthochromatic  types.  Another 
advantage  is  the  ease  of  handling  as  rela- 
tively bright  safelights  may  be  used. 

Picture  Tube  Phosphors 

To  match  these  film  characteristics, 
picture-tube  phosphors  are  available  with 
light  output  ranging  from  the  ultraviolet 
through  the  entire  visual  spectrum. 
Three  types  of  phosphors  in  common  use 
in  television  techniques  are  as   follows: 

1.  PI,  green  fluorescence,  commonly 
used  in  oscillographic  work.  It  is  the 
most  efficient  visually,  but  has  poor  ac- 
tinic efficiency. 

2.  P4,  white  fluorescence,  used  for  b- 
and-w  reproduction  of  Tv  images  in  most 
home  receivers.  It  has  the  advantage  in 
picture-tube  photography  that  picture 
quality  is  most  readily  judged  visually. 


"HOW  IT 
WORKS' 


STOP 

"Wondering 

About" 
Television 

Sold  mine  of  practical  facts 

By  JOHN  F.  RIDER 

Television  is  in  the  eye  of  the  public 
and  in  the  minds  of  everyone  associ- 
ated with  the  motion  picture  industry. 


Here  Are 
The  Facts  on: 


How    TV     Pictures 
Produced  and  Sent 


are 


What     is 
Receiver 


in 


the     TV 


3.  Installation   and 
Orientation   of  TV 
Antennas 

4.  Recognition  of  Troubles 
in  TV   Receivers 

This  book  is  written  in  down-to-earth 
language.  You  don't  have  to  be  an 
engineer  to  understand  it.  The  entire 
book  carries  the  practical  along  with 
the  theoretical. 

203  Pages  Illustrated  $2.70 
Send  Coupon  Below  TODAY! 


.... ......  ORDER    WITH   THIS    COUPON---- 

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19  West  44  St.,  New  York  18,  N.  Y. 

Enclosed  find  $2.70  for  Television  "How  It  Works" 

Name    

Address    

City 


Zone. 


State. 


However,  some  P4  screens  have  unde- 
sirable decay  characteristics. 

3.  P5  and  Pll,  these  two  phosphors 
are  blue  with  high  ultraviolet  output. 
Photographically  they  are  very  efficient. 
There  is  the  difficulty  in  using  a  blue 
phosphor  in  judging  the  quality  of  image 
visually,  because  of  the  fact  that  the 
human  eye  has  a  low  response  in  the  blue 
region  and  cannot  evaluate  the  quality 
of  the  ultraviolet  component  of  the  image- 
light  output  at  all. 

Tests  have  indicated  that  for  recording 
of  Tv  images  a  blue-fluorescing  screen 
(P5  or  Pll)  is  desirable,  since  it  makes 
possible  the  use  of  high-resolution,  low- 
cost,  positive  types  of  film  stocks.  The 
P5  screen  has  excellent  persistence  char- 
acteristics but  produces  a  somewhat 
lower  light  level  than  that  which  can  be 
obtained  with  Pll. 

Emulsion  position  in  the  final  print  is 
of  importance  in  Tv  because  films  may  be 
spliced  with  other  films  for  special  pur- 
poses. The  use  of  a  nonstandard  emul- 
sion position  requires  a  change  of  focus 
in  the  film  projector  when  interspliced 
with  films  using  a  standard  emulsion 
position.  This  would  require  the  con- 
stant attention  of  the  projectionist  to 
maintain  optimum  focus  throughout  the 
spliced  film,  therefore  it  is  advantageous 
to  insist  upon  a  standard  emulsion  posi- 
tion for  all  film  to  be  used  in  Tv.  The 
American  Standard  for  16-mm  film  is 
emulsion  "toward  the  screen." 

In  the  recording  of  Tv  images  there 
are  several  methods  of  obtaining  the  final 
print: 

Obtaining  the  Final  Print 

1.  The  use  of  reversible  film  stock  in 
photographing  a  positive  cathode-ray- 
tube  image.  A  dupe  negative  may  be 
made  of  this  material  from  which  addi- 
tional prints  can  be  made.  The  prints 
then  have  standard  emulsion  position; 

2.  Photography  using  high-contrast 
positive  stock  and  a  negative  picture-tube 
image  resulting  in  a  positive  print  from 
which  dupe  negatives  may  be  made  if 
production  prints  are  required.  These 
prints  will  have  standard  emulsion  posi- 
tion; 

3.  The  use  of  a  positive  image,  pho- 
tographing with  a  negative  type  of  film 
from  which  final  prints  are  made,  result- 
ing in  a  non-standard  emulsion  position. 
(By  reversing  the  direction  of  horizontal 
scanning,  however,  the  original  negative 
may  be  made  to  have  the  same  emulsion 
position  as  that  of  a  dupe  negative. 
Prints  made  from  this  negative  then  have 
standard  emulsion  position.) 

When  production  prints  are  required 
Method  3  is  now  used  almost  exclusively 
since  it  eliminates  the  use  of  a  dupe  nega- 
tive and  consequently  introduces  less 
total  degradation.  Methods  1  and  2  do 
not  produce  production  prints  of  suitable 
quality  for  present-day  commercial  Tv. 


32 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


PROJECTION    PREPARATIONS 
FOR    'SEASONAL'    THEATRES 

(Continued  from  page  10) 
ating  corrosion  of  the  metal.  The  con- 
dition of  the  flexible  asbestos-insulated 
cables  must  also  be  checked,  for  these 
cables,  being  composed  of  many  fine 
strands  of  wire,  are  particularly  liable 
to  oxidation. 

The  cut-out  points  of  arc  relays  may 
be  touched  up  by  drawing  00  sandpaper 
between  them  while  lightly  pressing  them 
together.  (For-  routine  cleaning  use 
heavy  writing  paper  in  place  of  the  00 
sandpaper.    Never  use  emery  paper!) 

Check  the  feed-motor  rheostat  and 
then  proceed  to  the  feed  motor  itself. 
Clean  and  check  the  condition  of  the 
commutator  and  the  brushes.  If  the 
commutator  is  scored,  touch  it  up  with 
00  sandpaper  followed  with  writing 
paper.  Do  not  use  emery  paper  or  cloth 
on  commutators! 

14.  Lamp  Optics.  Mirrors  and  con- 
densing lenses  must  be  taken  out  of  the 
lamphouse  for  thorough  cleaning.  The 
very  gentlest  handling  of  these  optical 
elements  is  the  best  protection  against 
accidental  breakage.  Approved  cleaning 
methods  for  lamphouse  optics  have  al- 
ready appeared  in  IP1.  Damaged  and 
defective  mirrors  should  be  replaced 
without  delay. 

The  projector  optical  train  may  now 
be  lined  up  by  any  of  the  usual  methods 
— passing  an  aligning  rod  or  stretching 
a  string  through  the  optical  centers  of 
the     components,     or     simply     sighting 

1  "Optical  Efficiency  in  Projection,"  IP  for  May, 
1948.  Refer  to  the  section  headed  "Optical  Surfaces 
Cleanliness"  on  p.  6  of  that  issue. 


BUILDING 


DRIVE-IN 


Write  for  book  on 
the  design,  construc- 
tion and  equipping 
of  drive-in  theatres. 

MONOGRAPH 

INC. 
4431  W.  lok.  SI.. 
Chitogo  14,  III. 


through  the  machine.  The  arc  should 
not  be  struck  until  the  generator  or 
rectifier  has  been  checked. 

15.  Generators  or  Rectifiers. 
Check  the  condition  of  the  ballast  rheo- 
stats and  their  connections.  When  the 
current-supplying  device  is  a  motor-gen- 
erator set,  proceed  as  follows: 

Turn  the  generator  over  by  hand  to 
note  the  "feel"  of  the  machine.  Care- 
fully blow  out  all  dust  from  the  interior. 
Examine  the  commutator  and  the  brushes 
for  wear  and  defects.  Clean  the  com- 
mutator, scrape  away  all  dirt  from  the 
mica  spacers  between  the  copper  bars, 
and  dress  the  commutator  by  applying 
a  mere  trace  of  petroleum  ("Vaseline") 
to  its  surface.  Correct  improper  brush 
tension. 

Grease  the  generator  per  manufac- 
turer's instructions.  Run-in  the  genera- 
tor for  30  minutes  before  drawing  cur- 
rent from  it. 

If  the  current-supplying  outfit  is  a  recti- 
fier, clean  the  cabinets  and  note  the 
condition  of  the  chemical  stacks,  blower 
motors,  etc.  In  the  case  of  tungar-type 
rectifiers,  test  all  tubes  for  plate  current 
and  replace  the  weak  ones. 

All  switches  not  previously  examined 
should  now  be  checked.  Familiarize 
yourself  with  the  switchboards,  fuse 
blocks,  etc.,  and  replenish  the  supply  of 
spare  fuses. 

16.  Light  Test.  Burn-in  a  new  trim 
of  carbons  in  each  lamp.  Adjust  the 
arc-feed  mechanisms  to  maintain  the 
correct  arc  gap. 

Project  blank  light  to  the  screen. 
(Guard  against  lens  injury  by  running 
the  projectors,  if  rear-shutter  models,  and 
employing  only  brief  flashes  of  light  for 
the  test.)  Adjust  the  reflector  for  the 
most  uniform  screen  illumination,  and 
adjust  arc-mirror  distance  to  obtain  the 
brightest  light.  Now  adjust  the  arc- 
indicator  so  that  the  image  of  the  positive 
crater  coincides  with  the  line  on  the  arco- 
scope  card. 

Adjustment  of  mirror-aperture  distance 
may  be  necessary  in   some  cases,  espe- 


\ 


Wenzel  Presents  . . .  SOUND  HEAD  WSH- 


\<WN 


\\* 


*P 


/. 


7 


Send  for  complete  descriptive  circulars,  giving 
full  details  of  the  many  advantages  of  this 
new  WENZEL  product. 

WENZEL   PROJECTOR   CO 


2505-19   S.   State  St. 
Chicago     16,     III. 


CAROL  A.  NATHAN— Co-Partner, 
Marina  and  El  Presidio  Theatres, 
San  Francisco,  Calif. — says: 

"We  have  been  using  RCA  Ser- 
vice exclusively  in  our  theatres 
since  the  inception  of  sound.  Con- 
gratulations on  your  marvelous 
service  and  organization." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


33 


cially  when  the  light  output  of  the  pro- 
jectors is  not  balanced. 

"With  the  lens-holder  of  each  machine 
loosened  and  the  focusing  carriage  in 
midway  position,  move  the  lens  in  or  out 
by  hand  until  a  sharp  image  of  the 
aperture  edges  is  projected  on  the  screen. 
Then  carefully  pull  the  lens  out  toward 
the  screen  until  the  aperture  image  is 
only  very  slightly  blurred.  Tighten  the 
nuts  of  the  lens-holder  with  the  lens  in 
this  position. 

If  necessary,  make  pedestal  adjust- 
ments so  that  the  projected  fields  of  both 
projectors  coincide  on  the  screen.  Men- 
tally note  desired  changes  in  the  place- 
ment of  the  screen  masking  battens. 

17.  Screen  and  Curtains.  Make  the 
necessary  changes  in  the  screen  masking 
and  note  the  condition  of  the  screen. 
Dust  spots  may  sometimes  be  brushed 
away  with  a  soft  brush  or  clean  cloth. 

Check  grand-drape  and  title-curtain 
controls,  and  ascertain  the  closing  time 
of  the  title  curtain — information  needed 
for  "cueing"  films. 

Check  striplights,  footlights,  etc.,  for 
burned-out  bulbs  and  bulbs  of  the  wrong 
size  or  color.  Make  certain  that  all  pro- 
jection and  observation  port  glasses  are 
of  the  best  quality  and  scrupulously 
clean.  (See  "Emphasis  on  the  Port 
Side"  by  A.  Buckley,  IP  for  January, 
1949,  p.  12.) 

18.  Picture  Test.  Use  a  good- 
quality  print  for  test  purposes.  Before 
threading  up,  however,  check  the  timing 
of  the  occulting  shutter.  Bring  the 
manual  shutter  adjustment  to  the  mid- 
way point.    Free  the  shutter  on  its  shaft. 


Place  a  reference  marker  over  any  tooth 
of  the  intermittent  sprocket  when  at  rest. 
Turn  the  mechanism  by  hand,  and  when 
the  second  tooth  from  the  first  comes 
under  the  marker,  turn  the  loosened 
shutter  to  mid-occultation  position. 
Tighten  the  shutter  screws.  (See  ad- 
jacent boxed  comment  on  shutter  blade 
width.) 

Set  the  framer  midway  and  thread  up 
the  reel  of  film.  Project  the  picture  and 
sharpen  focus  and  framing  adjustments. 
Note  carefully  any  defects  which  require 
correction — the  adjustment  of  the  lateral 
guide  rollers,  for  example.  (There  is  no 
need   for  sound   during  this   test.) 

19.  Sound  System  and  Sound  Test. 
It  is  assumed  here  that  the  complex  tests 
and  adjustments  necessary  in  connection 
with  the  sound  system  will  be  made  by 
a  sound  service  engineer.  The  projec- 
tionist not  having  the  benefit  of  sound 
service  ordinarily  must  rely  on  the  usual 
circuit-  and  tube-testing  methods.  The 
focus  of  soundhead  optics  may  be  set  by 
the  "flicker-test"  method.3  The  lenses 
of  the  optical  tubes  must  be  cleaned 
from  time  to  time,  of  course,  but  care 
should  be  taken  not  to  disturb  the  focus. 

A  final  check-up  on  the  sound  may  be 
conducted  by  running  films  in  both  pro- 
jectors simultaneously  and  switching  the 
fader  back  and  forth  to  determine 
whether  the  output  level  of  both  ma- 
chines is  the  same.  The  closeness  of  the 
"match"  should  be  within  x/2  db.  Sound 
quality,  particularly  the  clearness  of  the 


3  See  "Control  of  Sound-Film  Reproduction,"  IP  for 
July,  1948,  p.  5.  The  flicker  test  is  given  on  p.  7  of 
that  is9ue. 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

INTERNATIONAL    PROJECTIONIST. 
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□  2   years — 24   issues — $4.00 
Foreign  and  Canada:    Add  50c  per   year. 


Enter  my  subscription  for 


Name 


Address 


City 


State 


S.  EDWARD  KAPNER— Owner, 
Park  Theatre,  Philadelphia,  Penn- 
sylvania— writes: 

"For  the  last  4  years  RCA  Ser- 
vice has  maintained  my  sound 
system  at  top-quality  perform- 
ance. I  would  not  be  without 
the  dependable  services  of  this 
organization." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


higher  tones,  should  be  checked  from  the 
auditorium. 

The  correlation  between  correct  "aver- 
age" auditorium  and  projection-room 
monitor  volume  levels  may  now  be  estab- 
lished. 

All  is  now  in  readiness  for  a  complete 
2-  or  3-reel  picture-and-sound  rehearsal 
which  will  provide  practice  in  opening 
and  closing  the  show  and  in  making 
changeovers. 

20.  Auxiliary  Apparatus.  A  check 
of  film  rewinders,  splicers,  storage  cabi- 
nets, stereopticons,  spotlights,  etc.,  is  in 
order.  The  non-synchronous  phonograph 
is  also  to  be  examined  for  mechanical 
and  electrical  defects.  Frequency  re- 
sponse changes  may  be  necessary  when 
disk  reproduction  is  unsatisfactory. 

Projection  preparations  in  drive-in 
theatres  are  comparatively  simple.  This 
type  of  theatre  is  a  fairly  recent  innova- 
tion, hence  the  projection  equipment  in- 
stalled in  such  operations  is  compara- 
tively modern.  Sound  tests  in  drive-in 
theatres  include  a  check  of  all  plug-in 
boxes  and  in-car  speakers. 

Screen  problems,  too,  are  different  from 
those  in  permanent  theatres.  Evidences 
of  weathering  on  the  screen  surface  call 
for  a  repainting  of  the  entire  screen. 

The  suggested  procedure  for  lining  up 
the  equipment  in  the  "permanent"  type 
of  theatre  is  applicable  in  a  general  way 
to  drive-in  and  "temporary"  theatres. 
The  projectionist  assigned  to  a  summer 
theatre  can  make  certain  of  conserving 
time  and  effort  by  taking  this  copy  of 
IP  along  with  him,  or  else  jotting  down 
in  his  notebook  the  numbered  capital- 
letter  headings  of  the  20  steps  presented 
herein. 


34 


INTERNATIONAL  PROJECTIONIST     •     April  1949 


SO  MUCH 


for  so  LITTLE 


$Q.OO 


3 


per  copy 
postage   prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


Sand  foh  it  Wow! 


(Do  Wot  (DsLcuf 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street,  New  York  18,  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a   copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
Name  


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aty   


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SOUTH  OF  THE  BORDER 

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SOUND   AND   PROJECTS© 


The  last  word  in  luxury  and 
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Mexico,  has  installed  SIMPLEX  Sound 
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MANUFACTURED    BY    INTERNATIONAL    PROJECTOR    CORPORATION   •    BLOOMFIELD,    NEW  JERSEY 


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mister 


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Cancer's  annual  toll  of  200,000  lives  is  grim  proof  of  the  need 
for  your  continued  generosity.  The  money  you  contribute 
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Cancer  .  . ,  people  who  might  otherwise  have  died.  Your  money 
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INTERNATIONAL 

fOECTIONISlI 

With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


/ 


MAY  1949 


Number  5 


Index  and  Monthly  Chat 3 

Elementary    Laws    of    Electron- 
Optics 5 

A.  Buckley 

Letters  to  the  Editor   8 

Tv  Film  Projectors   9 

G.  W.  Tunnell 

The  Man  in  the  Tropical  'Box'       12 
Run  Run  Shaw 

Psychological  Elements  in  Pro- 
jection         14 

Robert  A.  Mitchell 

In  the  Spotlight 16 

Harry  Sherman 


IA  Elections   17 

Safety  Film  is  Now  Vq  of  All 
Prints;  Estimate  14  Level  by 
Sept.   1    18 

Optical    Factors    in    Arc    Lamp 

Design   19 

J.  K.  Elderkin 
R.  A.  Mitchell 

Telecasts    20 

Addendum  to  SMPE  Screen 
Brightness  Report    21 

Book  Review    23 

Personal  Notes 24 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING   CO.,   INC. 

19  West  44  Street,  New  York   18,  N.   Y. 

R.  A.   ENTRACHT,   Publisher 

SUBSCRIPTION   REPRESENTATIVES 

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Publishing  Co.,  Inc.  International  Projf.ctionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


>420 


MONTHLY    CHAT 


RECENT  joint  efforts  of  the  Theatre 
Owners  of  America  and  the  SMPE  to 
formulate  a  practical  plan  for  theatre 
television  was  ridiculed  by  a  streamer- 
headed  story  in  The  Film  Daily,  the 
Washington  correspondent  of  which 
quoted  a  "source  close  to  the  Federal 
Communications  Commission"  as  stating 
that  it  was  "preposterous"  for  the  theatre 
field  to  expect  the  allocation  of  exclusive 
channels  for  the  transmission  of  motion 
pictures  to  theatres.  The  story  added 
that  the  opinion  was  in  line  with  the 
oft-expressed  views  of  the  FCC  anent 
"freedom  of  the  air." 

Now,  this  story  seems  to  us  to  consti- 
tute the  erection  of  a  straw  man  solely 
for  the  purpose  of  knocking  him  down, 
because  it  is  "preposterous"  to  imagine 
experienced  hands  such  as  those  com- 
prising the  TOA-SMPE  committee  ap- 
proaching the  FCC  on  any  such  basis. 
It  would  seem,  also,  that  somebody  with 
a  deep  interest  in  transmission  by 
coaxial  cable  helped  mightily  in  creating 
the  mood  for  the  story. 

There  is  a  well-defined  path  for  the 
TOA-SMPE  group  to  tread  in  approach- 
ing the  FCC,  a  path,  let  it  be  said  em- 
phatically, that  augurs  well  for  ultimate 
success.  The  first  step  would  be  to  re- 
quest an  experimental  license  for  a  serv- 
ice which  is  considered  to  be  useful, 
technically  feasible,  and  in  the  public 
interest.  Such  a  license  would  undoubt- 
edly be  granted. 

Three  months  later  the  FCC  could  be 
approached  again  for  an  extension  of 
the  license  on  the  basis  that  preliminary  j 
tests  had  proven  very  encouraging  but 
that  more  time  was  required  to  improve 
the  system.  This  request,  too,  likely 
would  be  granted.  Six  months  later,  on 
the  basis  of  intensive  tests  and  accumu- 
lated experience,  the  FCC  could  be  peti- 
tioned to  hold  a  public  hearing  at  which 
testimony  from  all  interested  parties,  pro 
and  con,  and  engineering  data  could  be 
aired.  Following  such  a  hearing,  and 
in  the  likely  absence  of  any  serious  op- 
position, application  could  be  made  for, 
say,  12  channels;  and  the  motion  picture 
people  would  probably  wind  up  with 
three  channels. 

Thus  the  procedure,  one  which  is  held 
by  experienced  people  to  hold  out  great 
promise  for  the  motion  picture  field. 
Meetings  of  the  TOA  and  SMPE  are 
held  regularly,  and  it  is  reported  that 
sufficient  progress  has  been  made  to 
render  likely  an  early  request  of  the 
FCC  for  an  experimental  license. 

The  theatre  field  is  laboring  under 
the  dual  handicap  of  a  very  late  start 
in  the  Tv  field  and  the  inevitable  division 
of  opinion  and  interest  among  exhibitors. 
The  task  ahead  is  tough  enough  without 
having  to  saddle  the  added  burden 
created  by  such  uninformed  stories  of 
the  kind  mentioned  above. 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


How  the  Navy  uses 
Western  Electric 
recording  equipment 


Wesfern  Electric  "300"  recording  system  in 
use  aboard  Navy  Electronics  Laboratory  ves- 
sel at  sea.  (Official  photograph  U.  S.  Navy) 


U.  S.  Navy  scientists  use  Western 
Electric  sound  film  recording  equip- 
ment to  make  on-the-spot  records  of 
the  operation  of  sonar,  radar,  fire  con- 
trol and  other  naval  electronic  equip- 
ment. These  sound  motion  pictures 
provide  a  permanent  record  for  labora- 
tory study  whenever  and  wherever 
needed. 

Of  particular  value  for  use  at  sea — 
and  beneath  the  sea  in  submarines — 


is  the  "300"  recording  system  shown 
above.  Compact  and  portable,  with 
the  dependability  needed  for  extended 
cruises,  this  equipment  effectively  re- 
cords the  low  frequency  sound  reflec- 
tions and  the  high  frequency  transients 
encountered  in  sonar  and  radar  studies. 
It  is  this  dependability  and  fine  sound 
quality  which  have  made  Western 
Electric  recording  equipment  the  fa- 
vorite throughout  the  Avorld.   - 


Wfim 


9K 


Electrical  Research  Products  Division 


Western  Electric  Company 

INCORPORATED-  *  M 


5H 


■ 


120  BROADWAY,  NEW  YORK  5,  N.Y. 

Hollywood    office  —  6601    Romaine.  St. 


VOLUME  XXIV 


MAY  1949 


NUMBER  5 


Elementary  Laws  of  Electron-Optics 


THE  thorough  study  of  light  and  op- 
tics entails  quite  some  mathematical 
work  even  for  the  student  who  is 
well-versed  in  such  matters;  for  the  lay- 
man, conversant  with  abbreviated  formu- 
lae, a  certain  degree  of  interest  may 
exist.  But  the  majority  of  people  regard 
involved  formulae  as  very  dry  and  a 
necessary  evil;  while  still  another  group 
of  the  uninitiated  regard  math  as  a  lot 
of  undecipherable  hieroglyphics. 

If  the  appended  observations  err,  they 
do  so  on  the  score  of  simplicity,  with  the 
mathematical  angles  being  completely 
ignored. 

The  Cathode-Ray  Tube 

Most  engineers  and  projectionists  are 
familiar  with  cathode-ray  tubes,  since  so 
many  were  used  during  wartime  in  all 
the  services,  and  today  they  are  common- 
place in  the  electronic  art.  The  term 
"cathode-ray  tube"  is  not  quite  apt,  for 
since  the  basic  principle  depends  upon 
an  "electron  beam"  or  "electron  jet," 
possibly  a  more  suitable  name  would  be 
"electron  tube." 

In  its  simplest  form,  a  cathode-ray 
tube  consists  of  an  evacuated  glass  bulb 
— or  one  containing  an  inert  gas — and 
three  electrodes:  (a)  filament  (cath- 
ode) ;  (b)  anode,  and  (c)  cylinder.   Nor- 


FIGURE  1 


Some  notes  regarding  electrons  in 
motion,  and  a  comparison  of  their 
behavior  with  that  of  light. 

By  A.    BUCKLEY 

mally,  the  filament  is  heated  by  a  two- 
volt  supply,  a  positive  potential  is  ap- 
plied to  the  anode,  and  a  negative  bias  is 
applied  to  the  cylinder. 

Figure  1  illustrates  in  schematic  form 
the  general  idea.  Electrons  emitted  by 
the  cathode  are  attracted  by  the  concen- 
tric anode,  and,  due  to  the  repulsion 
exerted  by  the  negative-biased  cylinder, 
they  are  concentrated  into  a  "pencil"  or 
beam. 

Often  in  a  "hard"  tube  (i.e.,  one  highly 
evacuated)  additional  anodes  are  used  to 
bring  the  electron  beam  to  a  focus  on 
the  fluorescent  screen  at  the  end  of  the 
tube.  In  such  a  tube  the  pencil  of  rays 
is  quite  invisible  until  it  reaches  the 
chemical  screen  (which  in  a  primitive 
tube  may  consist  of  zinc  sulphide)  when, 
due  to  the  bombardment  by  high-velocity 
electrons,  visible  light  is  produced. 

The  Rectilinear  Propagation 
of  Light  and  Electrons 

In  the  case  of  a  gas-focused  tube,  the 
electron  beam  can  often  be  seen,  for  the 
electrons  moving  with  high  velocity  hit 
the  gas  particles  and  become  luminous. 
Similarly,  in  a  "soft"  power  tube  the 
modulations  of  speech  and  music  can  be 
"seen"  in  the  form  of  varying  degrees  of 
ionization.     The  result  is  a  bluish  glow 


which    varies    constantly    in    brilliancy. 

Normally,  electrons  moving  in  the 
form  of  a  beam  from  cathode  to  anode, 
and  beyond,  as  shown  in  Fig.  1,  proceed 
in  perfectly  straight  lines,  just  like  light 
rays.  When  either  electrons  or  light 
rays  proceed  in  perfectly  straight  lines, 
their  behavior  is  said  to  be  "rectilinear." 

Light  rays  are  reflected  by  mirrors  and 
refracted  by  lenses.  Electron  beams  are 
controlled  by  either  electrostatic  or  elec- 
tromagnetic means.  Let  us  discuss  sev- 
eral points  relative  to  this  means  of 
control  which  has  given  rise  to  the  term 
"electron-optics." 

From  first  principles  we  know  that 
electrons,  being  characteristically  nega- 
tive, are  attracted  by  a  positively-charged 
body  and  repelled  by  a  negatively- 
charged  one;  also,  the  presence  of  a 
magnetic  state  causes  the  bending  (or 
changing  of  the  shape)  of  an  electron 
beam.  Figs.  2,  3,  and  4  show  just  how 
simple  deflection  occurs. 

When  light  passes  through  a  block  of 
glass  at  exactly  90  degrees,  its  course  is 
not  altered  (Fig.  5).  Similarly,  when  a 
pencil  beam  of  electrons  passes  between 


FIGURE  2 


FIGURE  3 


INTERNATIONAL  PROJECTIONIST 


May  1949 


FIGURE  4 


N 


FIGURE   5 


While  in  some  instances  almost  exact 
similarities  exist  between  light  and  elec- 
tron-optics, in  other  cases  the  behavior 
of  the  two  exhibits  a  direct  contrast.  The 
general  ideas  are  the  same  in  connection 
with  reflection,  refraction  and  deviation, 
but  in  detail  there  are  certain  differences. 
For  instance,  when  light  passes  from  air 
to  glass  the  change  is  abrupt;  whereas 
in  the  case  of  electron  movement  the 
strength  of  the  electrostatic  or  magnetic 
field  is  gradual. 

Of  special  interest  is  that  the  speed  of 
light  is  reduced  when  passing  through  a 
denser  medium  (i.e.,  when  light  passes 
from  air  to  glass,  it  passes  from  a  rarer 
to  a  denser  medium)  ;  but  in  the  case 
of  electrons  in  motion,  the  velocity  is 
increased  within  the  refracting  space. 

The  comparison  between  the  perform- 
ance of  a  simple  double-convex  lens  and 
its  electrostatic  counterpart  is  indeed  of 


FIGURE  10 


FIGURE  T1 


two  uncharged  plates,  its  course  is  un- 
changed (Fig.  6).  If,  however,  a  beam 
of  light  enters  a  block  of  glass  at  any 
angle  up  to  a  critical  limit,  its  direction 
will  be  bent  toward  the  normal*,  or  per- 
pendicular, as  it  passes  through  the 
denser  medium.  Upon  emerging  it  will 
again  take  up  a  similar  but  displaced 
course    (Fig.  7). 

Change  in  Velocity  Effect 

Similarly,  an  electron  beam  entering  a 
region  such  as  is  shown  in  Fig.  8,  con- 
sisting of  two  fine-wire  meshes  at  differ- 
ent potentials,  will  be  bent  toward  the 
normal.  The  degree  of  electronic  refrac- 
tion will  depend  upon  the  intensities  of 
the  charges  on  the  wire  meshes,  the 
dimensions  of  the  screens,  and  the  close- 
ness of  the  mesh.  Likewise,  the  degree 
of  light  refraction  is  dependent  upon  the 
substance  through  which  the  beam 
passes. 

*  An  imaginary  line  at  right  angles  to  the  surface. 


FIGURE   6 


FIGURE   8 


FIGURE  7 


FIGURE  9 

interest.  Fig.  9  shows  the  usual  candle 
and  paths  of  the  light  rays  through  the 
lens,  and  the  resultant  image  on  the 
screen.  The  investigations  into  the  elec- 
tronic counterpart  of  this  and  other  ex- 
amples are  due  to  Knoll  and  Ruska  who 
constructed  an  electrostatic  lens  as 
shown  sectionally  in  Fig.  10.  This  sketch 
shows  how  the  curved  surfaces  of  the 
bi-convex  lens  were  replaced  by  two 
shaped  fine-wire  meshes  at  different 
potentials. 

Rays  of  Parallel  Origin 

Parallel  rays  proceeding  from  a  para- 
bolic mirror  or  from  a  light  source  at  a 
great  distance  (such  as  from  the  sun) 
may  be  brought  to  a  focus  by  a  double- 
convex  lens  as  shown  in  Fig.  11.  Simil- 
arly, in  a  cathode-ray  tube  the  electrons 
are  emitted  at  right  angles  from  a  rela- 
tively large  source;  therefore,  this  move- 
ment can  be  said  to  be  parallel  to  the 
axis  of  the  tube  (Fig.  12).    This  parallel 


FIGURE  12 

beam   can   be   focused   by   means   of   a 
Wehnelt  cylinder    (W). 

Another  law  of  optics  relative  to  the 
reflection  of  light  also  has  its  counter- 
part in  electron  optics.  A  source  ot 
light  can  be  seen  apparently  behind  the 
mirror  at  a  distance  equal  to  the  distance 
of  the  source  from  the  mirror,  as  shown 
in  Fig.  13.  In  like  fashion,  by  using 
fine-wire  meshes  an  exact  counterpart 
can  be  produced  in  connection  with  an 
electron  beam.  The  angles  of  incidence 
and  reflection  obey  the  same  laws  as  in 
light  optics   (Fig.  14). 

Deviation  by  Electrostatic  Prism 

When  a  beam  of  light  enters  a  plate 
of  glass  with  polished,  parallel  sides,  the 
angles  of  entrance  and  exit  will  be  equal, 
although  displaced  in  certain  instances. 
If  the  sides  of  the  glass  be  not  parallel, 
then    the    light    beam    will    be    bent    as 


"* 


FIGURE    13 


FIGURE   14 


INTERNATIONAL  PROJECTIONIST 


May  1949 


and  make  box  office 


UV\.  */./.V,/„/ 


! 


"National"  H.I.  Arc— 

"Brightest  spot 

in  the  world! 


The  term  "National" 
is  a  registered  trade-mark  of 

NATIONAL  CARBON  COMPANY,  INC. 

Unit  of 
Union  Carbide  and  Carbon  Corporation 

EH3 

30  East  42nd  Street,  New  York  17,  N.  Y. 

Division  Sales  Offices: 

Atlanta,  Chicago,  Dallas,  Kansas  City, 

New  York,  Pittsburgh,  San  Francisco 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


FIGURE  15 


FIGURE   16 

shown  in  Fig.  15.  This  block  of  glass 
is  called  a  "prism." 

In  electron  optics  the  same  thing  may 
be  accomplished  by  using  two  control 
plates  at  different  potentials.  As  in  all 
other  cases  of  electron  lenses,  the  amount 
of  deviation  will  depend  upon  the  magni- 
tude of  the  charges,  the  separation  of  the 
plates,  and  their  position  relative  to  the 
electron  beam.  Fig.  16  is  a  simple  ex- 
position of  how  this  occurs. 

Figure  17  shows  how  in  an  optical 
combination  two  lenses — one  of  crown, 
the  other  of  flint  glass — are  used  in  con- 
tact to  minimize  aberration  or  distortion. 
The  electron-optical  equivalent  of  such  a 
scheme  is  seen  in  Fig.  18,  together  with 
the  resultant  field.  The  bending  of  the 
electron  beam  and  its  focusing  will  be 
noted,  thus  the  analogies  are  again  very 
similar. 

Wire  Mesh  Screen  Deficiency 

Although,  as  wel  have  seen,  the  experi- 
mental use  of  wire  mesh  screens  is  the 
nearest  approach  to  the  glass  lenses  and 
mirrors  used  in  connection  with  light, 
they  are  not  used  in  cathode-ray  tubes. 
The  distortion  produced  by  these  mesh 
screens  is  considerable,  therefore  in  early 
cathode-ray  tubes  the  elements  consisted 
of  sheet  metal  tubes,  concentric  and  flat 
plates.  In  the  modern  tubes  magnetic 
focusing  and  deflection  are  used  more 
often. 

For  practical  explanations  and  com- 
parisons the  laws  of  light-optics  and 
electron-optics  are  very  similar;  but  the 
refracting,  reflecting  and  deviating  media 
are  totally  different  in  these  two  branches 
of  physics.  Lenses,  mirrors  and  prisms 
have  fixed  dimensions  and  constant  prop- 


FIGURE   17 


erties;  but  electron-optical  "lenses"  and 
other  devices  are  changeable  in  strength 
and  effects. 

In  light-optics  the  correction  of  spheri- 
cal aberration  or  distortion  may  be  ac- 
complished by  using  two  kinds  of  glass 
in  a  composite  lens;  in  electron-optics 
such  distortion  is  Usually  corrected  ex- 
perimentally by  changing  the  intensity 
or  direction  of  the  controlling  field.     A 


FIGURE  18 


To  the  Editor  of  IP: 

I  have  found  brand-new  Warner  Bro- 
thers prints  considerably  more  brittle 
than  those  .of  most  other  distributors. 
Since  the  film  stock  is  the  same  (East- 
man) it  seems  to  me  that  this  brittleness 
must  be  due  to  some  WB  variation  in 
processing  or  treatment. 

I  do  not  mean  that  WB  prints  are  likely 
to  break  in  projection — far  from  it.  The 
brittleness  consists  of  the  inability  of  the 
film  to  be  sharply  creased  without  break- 
ing. Paramount  prints,  on  the  other 
hand,  may  be  creased  and  "unbent" 
without  severance  of  the  print.  No,  I 
don't  run  prints  that  have  been  creased: 
I  cut  out  the  creased  part  and  splice. 
My  interest  lies  in  the  direction  of  a 
rather  fine  point  of  processing  technique. 
State  of  Maine  Projectionist 

[Warners  uses  exactly  the  same  Eastman 
system  of  edge-waxing  as  is  employed  by 
Metro  and  other  major  distributors.  No 
Warner  print  is  waxed  over  the  entire  film 
surface.  No  complaints  anent  brittleness  or 
any  other  deficiency  has  been  received  by 
the  Warner  lab  through  normal  channels. 

There  is  always  to  be  considered,  of 
course,  the  matter  of  climatic  conditions. 
In  Maine,  for  example,  the  atmosphere  is 
not  only  cold  but  dry,  and  this  might  con- 
ceivably contribute  to  the  "brittleness"  re- 
ferred to  by  this  correspondent — although 
this  does  not  explain  why  the  reference  is 
confined  to  Warner  prints. — Ed.] 

To  the  Editor  of  IP: 

Quite  a  few  years  back  a  group  of 
practical  projection  people  got  together 
and  did  a  splendid  piece  of  work  by 
establishing  the  Standard  Release  Print. 
This  was  a  wonderful  example  of  co- 
operative effort  among  several  branches 
of  the  industry  which  neither  before  nor 
since  have  jointly  supported  such 
projects. 

All  this  worthy  effort,  however,  is  being 
negatived  by  the  increasing  practice  of 
using  film  leaders  to  make  density  tests 
and  leaving  blank  spaces  in  the  rundown 
and  other  similar  variations  in  the  lead- 
ers of  reels. 

These  blank  spaces  in  leaders  make 
it  very  tough  for  the  projectionist  to 
frame     properly     when     threading     up. 


further  point  is  that  the  possibilities  of 
interaction  between  the  focusing  and 
modulating  electrodes  sometimes  exist. 
Although  the  subject  matter  of  this 
article  is  by  no  means  new,  it  is  felt 
that  this  simplified  exposition  of  a  diffi- 
cult subject  will  be  of  interest  to  those 
who  may  someday  handle  that  modern 
miracle  of  the  electronic  art — television. 


TO    THE    EDITOR 

Upon  inspecting  a  show  prior  to  its 
initial  run  the  writer  has  to  check  each 
and  every  reel  and  either  use  the  edge- 
markings  or  actually  measure  the  blank 
inserts  in  order  to  frame  correctly. 
Moreover,  these  blanks  almost  invariably 
have  one  or  two  patches  in  them,  thus 
making  them  unreliable  for  framing. 
Even  without  patches,  I  know  of  nobody 
who  can  frame  on  a  blank. 

It  would  seem  to  me  that  this  is  a  job 
for  the  Projection  Committee  of  the 
SMPE,  there  being  no  other  agency 
through  which  positive  corrective  action 
may  be  taken. 

Ken  Caldwell 
IA  Local  233,  Buffalo,  N.  Y. 

[This  is  by  no  means  the  only  departure 
from  SRP  standards  but  it  is  certainly  one 
of  the  more  flagrant  examples.  Corrective 
action  would  be  aided  by  supplying  the  title 
of  the  feature  and  its  distributor. — Ed.]  ' 

To  the  Editor  of  IP: 

My  recent  articles  covering  the  new 
British  projection  gear  seem  to  have 
caused  quite  a  lot  of  comment.  There- 
fore, let  me  say  here  and  now  that  in 
my  unbiased  opinion  there  is  little  amiss 
with  either  American  or  British  projec- 
tion gear.  All  new  machines,  whatever 
their  origin,  are  subject  to  teething  trou- 
bles, and  neither  American  nor  British 
machines  are  exempt  from  their  little 
worries  at  first. 

The  question  of  preference  for  one 
machine  or  the  other  depends  on  one's 
outlook,  just  as  if  one  is  buying  a  car 
or  a  typewriter.  Basically,  picture  pro- 
jection was  as  good  15  years  ago  as  it 
is  today.  The  weakest  link  in  any 
motion  picture  outfit  still  is  the  human 
element.  Skilled  hands  can  usually  get 
more  out  of  old,  obsolete  equipment  than 
unskilled  ones  can  get  out  of  the  new. 

H.  Hill,  British  Observer  for  IP 


God  (and  Science)  Save  the  King 

If  you  were  a  projectionist  in  Siam,  you 
would  be  required  by  law  to  close  each  pro- 
gram with  a  screen  projection  of  the  like- 
ness of  the  King  the  while  you  played  a 
recording!  of  the  Siamese  national  anthem. 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


FIG.  1.  Simplest  arrangement  of  RCA  16-mm 
Tv  projector  (left)  and  film  camera  (right). 
The  image  is  projected  through  the  rectangu- 
lar opening  in  the  camera  onto  the  face  of  an 
Iconoscope  tube. 

TELEVISION  (Tv)  film  projectors 
are  fundamentally  similar  to  stand- 
ard 16-mm  and  to  35-mm  theatre- 
type  motion  picture  projectors.  The 
principal  difference  is  that  the  Tv  pro- 
jector must  synchronize  with  the  Tv 
system.  In  the  RCA  16-mm  Tv  pro- 
jector this  is  assured  by  the  fact  that 
both  the  Tv  synchronizing  generator 
(which  drives  the  beam  in  the  camera 
pickup  tube)  and  the  motor  (which 
drives  the  projector)  have  a  common 
source  of  power  in  the  60-cycle  power 
line. 

To  insure  that  the  shutter  will  be  "in 
step"  at  all  times,  a  large-size  motor  with 
a  separately-excited  d-c  field  is  used.  The 
d-c  field,  being  polarized,  makes  the 
motor    always    "look"    in    proper    phase 


Tv  Film 
Projectors 


By  G.  W.  TUNNELL 

Engineering  Products  Section 
Radio  Corporation  of  America 


relationship      with      the      synchronizing 
generator. 

In  the  Tv  system,  the  projector  pro- 
jects the  image  onto  the  face  (mosaic) 
of  an  Iconscope  pickup  tube  which  is 
located  in  the  film  camera.  Fig.  1 
represents  a  typical  arrangement  of  the 
projector  and  the  film  camera. 

Iconoscope  Film  Pickup 

Let  us  consider  the  Iconoscope  in  the 
film  camera  as  the  electronic  eye  which 
rapidly  scans  the  projected  image  and 
thus  transforms  the  picture  information 
received  from  the  film  projector  into  the 
proper  electronic  signals  for  Tv  trans- 
mission purposes. 

In  order  to  obtain  complete  picture 
information  it  is  necessary  that  this  elec- 
tronic eye  open  and  close  at  a  uniform 
rate  of  speed.  A  speed  of  60  times  per 
second  has  been  chosen  for  Tv  because 
it  may  easily  be  referenced  to  the  power- 
line  frequency  which  is  standardized 
nationally.* 


*  With    a    few    exceptions. 


FIG.  3.   Closeup  of  shutter  and  takeup  mechan- 
ism.    The  sound  preamplifier  is  located  below. 
Projector  covers  removed   for  this  shot. 

This  process  is  called  "scanning"  and 
is  accomplished  by  causing  the  electron 
beam  to  travel  across  the  image  on  the 
mosaic  in  a  series  of  horizontal  lines. 
Two  scannings  or  fields  (1/60  second 
duration  each)  are  required  to  make  a 
complete  Tv  frame  (1/30  second  dura- 
tion) due  to  a  process  called  "inter- 
lacing" (alternate  line  scanning).  It 
may  be  seen,  therefore,  that  30  complete 
frames  are  scanned  each  second. 

If  motion  picture  practice  utilized  a  30- 
frame-per-second  rate  of  exposure,  then 
a  single  Tv  frame  would  correspond 
exactly    to    a    frame    of   motion    picture 


FIG.  2.  Showing  the  time  relationship  of  the  framing  light  and 
the  scanning  sequences  employed  in  the  RCA  16-mm  Tv  pro- 
jector (Type  TP-16B).  Line  A  shows  the  pull-down  interval  in 
a  standard  16-mm  projector,  which  is  about  1/6  of  the  total 
frame  cycle.  Line  B  shows  the  effect  of  speeding  up  the  pull- 
down, which  is  now  only  1/8  the  total  frame  cycle. 

Line    C    indicates    the    duration    and    repetition    rate    of   the 


short  intervals  during  which  light  is  allowed  to  fall  upon  the 
film.  Note  that  Frame  1  is  illuminated  twice,  Frame  2  three 
times,  and  so  on.  Line  D  shows  the  scanning  intervals.  Note 
that  scanning  is  accomplished  during  the  unlighted  interval 
following  each  period  of  illumination.  This  is  made  possible  by 
the  "storage"  or  "memory"  property  of  the  Iconoscope,  the  tube 
which  has  been  greatly  improved  since  its  introduction. 


Pulldown 
Standard 
Projector 


-  £J  SECOND 


'A 


B.    Pulldown  in 
Television 
Projector 


PULLDOWN 
V7, 


C.    Light    Flashes 
60  Per  J 

Second 


FRAME  '2 


—j  [—  T2B5  SEC0ND 

o       a 


D.    Scanning 
Fields  60   Per 
Second 


I—  eb  second— \ 


TIME-*- 
INTERNATIONAL  PROJECTIONIST 


May  1949 


-I  I- A 


D 


SECOND 


r^i 


A 


a 


PULL  DOWN  CLAW 


film.  Since  motion  picture  technique  has 
already  established  a  24-frame  rate,  it 
was  necessary  to  develop  a  method  of 
using  the  24-frame  projector  with  the 
30-frame  Tv  system. 

Alternate  Scanning  Frequency 

In  the  RCA  16-mm  projector  this 
method  is  often  referred  to  as  2-3-2-3 
scanning.  This  method  permits  the  film 
camera  to  scan  the  first  film  frame  twice, 
the  second  three  times,  the  third  twice, 
the  fourth  three  times,  etc. 

The  average  rate,  then,  is  21/2  scan- 
nings per  film  frame,  which,  when  multi- 
plied by  24  film  frames  per  second, 
provides  60  scanned  fields  per  second, 
which,  when  interlaced,  is  30  Tv  frames 
per  second.  Thus  is  accomplished  the 
use  of  a  24-frame  projector  with  a  30- 
frame  Tv  system. 

Figure  2  reveals  how  this  type  of  scan- 
ning is  accomplished.  Line  D  shows  a 
standard  Tv  film  camera  cycle.  Tivo 
successive  scans  of  1/60  second  duration 


tCA    3Smm    TELEVISION 

PROJECTOR    OR    RCA 

14mm    PROJECTOR 


RCA  Multiplexer — For  uninterrupted  pro- 
jection of  multireel  films  where  two  pro- 
jectors are  needed.  This  ingenious  device 
eliminates  the  need  for  an  additional  film 
camera.  It  consists  of  a  V-shaped  mirror 
for  reflecting  images  from  either  projector 
to  film  camera,  and  a  slide  film  projector  for 
inserting  station  breaks,  commercials,  etc. 


FIG.  4. 
Diagramati- 
cal  represen- 
tation of  the 
optical  system 
and    film-feed 
arrangement 
of  the  RCA 
16-mm  Tv 
projector. 


are  required  to  make  one  complete  Tv 
frame,  which,  of  course,  results  in  the 
30-frame  rate  mentioned  previously. 

The  spaces  shown  between  the  scan- 
ning   fields    are    known    as    "blanking 


FIG.  5.  Graphical 
comparison  between 
standard  theatre  and 
Tv  35-mm  intermit- 
tent movements. 


THEATRE 

periods."  It  is  during  this  blanking 
period  that  bursts  of  light  containing 
picture  information  are  transmitted  from 

FIGURE  6 

How  it  Works — Line  A  shows  the  pull- 
down timing  of  a  standard  35-mm  film  pro- 
jector (no  lighting  during  90°  pull-down). 
Line  B  shows  pull-down  timing  of  the  RCA 
35-mm  television  projector — and  the  dura- 
tion and  repetition  rate  of  the  short  intervals 
during  which  light  passes  through  the  film. 
Line  C  shows  the  projector  lighting  inter- 
val of  the  35-mm  television  projector.  The 
"light-on"  intervals  are  produced  by  a  pulse- 
controlled    camera    lamp    that    produces    an 


360°  (1/24  SECOND) 


FRAME  No.  1 


-90° 


288°  (1/30  SECOND) 


the  projector  through  the  film  to  the  film 
camera.  The  Iconoscope  used  in  the 
film  camera  has  a  storage-of-memory 
characteristic  which  permits  it  to  retain 
the  information  received  from  the  light 
burst  for  a  period  long  enough  to  scan 
one  field.  The  source  of  light  is  a  1000- 
watt,  115-volt  lamp. 

The  duration  of  these  light  bursts  is 
controlled  by  the  size  of  the  opening 
in  the  rotating  shutter  (Fig.  3).  It  is 
now  evident  that  these  bursts  of  light 
will  deposit  intelligent  picture  informa- 
tion on  the  mosaic  of  the  Iconoscope  only 
if  the  motion  picture  film  is  stationary 
in  the  aperture. 

Shortened  Pull-Down  Period 

If  pull-down  periods  of  standard  dura- 
tion were  used  as  in  Line  A  (Fig.  2), 
the  light  bursts  would  transmit  informa- 
tion appearing  in  the  aperture  during 
the  pull-down  period.     In  view  of  this, 


TELEVISION 

it  is  necessary  to  shorten  the  pull-down 
period  to  the  point  where  it  will  not 
disturb  the  transmission  of  the  picture 

800-microsecond  flash  every  l/60th  second. 
The  picture  images  are  projected  onto  the 
film  camera  pick-up  tube  during  the  retrace 
(blanking)  interval  of  its  scanning  beam. 
The  "storage"  property  of  the  tube  permits 
scanning  during  the  unlighted  interval  be- 
tween flashes. 

Scanning  releases  the  picture  charge — - 
converts  it  into  a  video  signal.  A  synchroni- 
zing generator  keeps  the  projector  and  film 
camera  in  phase. 


FRAME  No.  2 


K-  1  /60  SECOND  -H 


TELEVISION 
FIELD 


5%  LIGHTING  INTERVAL 


TELEVISION 
FIELD 


TELEVISION 
FIELD 


TELEVISION 
FIELD 


TELEVISION 
FIELD 


TELEVISION 
FIELD 


UNLIGHTED  INTERVAL 
'.FILM  CAMERA  SCAN) 


TELEVISION  FRAME  - 


10 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


$£> 


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/ 


THE  STRONG  MOGUL 

PROJECTION      ARC      LAMP 

PROJECTS  THE  MAXIMUM  LIGHT  THAT  FILM  WILL   ACCEPT  WITHOUT  DAMAGE 


USE  THIS  COUPON  TODAY  FOR  DEMONSTRATION  OR  LITERATURE 


II 


THE  STRONG  ELECTRIC  CORPORATION 

"The  World's  Largest  Manufacturer  of  Projection  Arc  Lamps" 
II    31   City  Park  Avenue  Toledo  2,  Ohio 

Q  I  would  like  a  demonstration  of  Strong  lamps  in  my  theatre,  without  cost 
or  obligation. 
Please  send  free  literature  on  the: 

□  Mogul  Lamp  □  Utility  1  K.W.H.  I.  Lamp  □  Strong  Rectifiers 

I    |  Strong  Reflectors  Q  Strong  Arc  Spotlamps 

NAME 


^fcwTj^^ew^  STRONG -fa pktuteutvffr/  j 


THEATRE- 
STREET — 


CITY  AND  STATE- 


information.  Pull-down  periods  of  the 
duration  shown  in  Line  B,  Fig.  2,  are 
those  used  in  the  RCA  16-mm  Tv  pro- 
jector. 

The  shorter  pull-down  period  must 
be  provided  without  destroying  the  aver- 
age film  speed  of  24  frames  per  second 
through  the  projector,  inasmuch  as 
sound  reproduction  must  continue  at  a 
24-frame  rate.  RCA  has  chosen  elliptical 
gears  for  use  in  the  pull-down  mechan- 
ism. These  gears  increase  the  pull-down 
speed  by  about  50%  as  compared  with  a 
standard  projector.  However,  the  24- 
frame  rate  through  the  sound  optical 
system  still  is  maintained. 

The  discussion  up  to  this  point  has 
centered  around  the  16-mm  projector; 
however,  a  few  facts  anent  the  RCA 
35-mm  Tv  projector  should  prove  help- 
ful. The  principal  constructional  differ- 
ences  between   the  two   projectors   are: 

(1)  the  action  of  the  intermittent,  and 

(2)  the  type  of  light  source  utilized. 

35-mm  Tv  Projector  Intermittent 

The  intermittent  mechanism  in  the 
35-mm  Tv  projector  is  a  special  Geneva 
movement.  A  comparison  of  this  move- 
ment with  one  of  conventional  design  is 
shown  in  Fig.  5.  The  Tv  intermittent  is 
designed  to  allow  the  film  to  remain 
stationary  in  the  aperture  for  a  longer 
period  of  time  for  alternate  film  frames. 

Figure  6  shows  a  standard  35-mm 
intermittent  cycle  (Line  A)  and  a  Tv 
35-mm  intermittent  cycle  (Line  B)  com- 
pared with  the  requirements  of  the  film 
camera  (Line  C).  It  can  be  seen  that 
the  Tv  intermittent  causes  pull-down  to 
occur  at  positions  which  will  not  affect 
the  light  flashes  which  transmit  picture 
information  to  the  film  camera. 

The  light  flashes  occur  at  the  same 
rate  as  those  in  the  16-mm  Tv  projector, 
however,  they  are  created  by  a  flashing 

FIG.  7.  Closeup  of  the  35-mm  projector  head 
showing    lamphouse   with   gap    lamp    in    place. 


Herewith  the  verbatim  publication,  including  the  title,  of  a  contributoin  from  an  IP  subscriber 
for  many  years  (and,  incidentally,  a  Simplex  distributor)  whose  progressive  social  ideas  obviously 
are  not  affected  either  by  his  remote  location  or  his  intriguing  name. 

The  Man  in  the  Tropical    Box' 

By  RUN  RUN  SHAW 

Shaw  Enterprise,  Singapore,  Straits  Settlements 


NO  TENT  SHOWS,  THESE  TYPICAL  PROJECTION  ROOMS  IN  THE  STRAITS  SETTLEMENTS 
Capitol  Theatre,  Singapore  (left):  Simplex  E-7  projectors  and  sound  equipment,  Peerless  lamps, 
Brenkert  effect  projector,  Rect-O-Lite  rectifiers.  The  largest  in  Singapore,  this  theatre  was 
opened  in  1929.  Note  "surface  wiring."  The  Rex  Cinema,  Singapore  (right):  Super  Simplex 
projectors,  RCA  sound.  Peerless  lamps,  and   tungar  rectifiers. 


PROMPTLY  at  11  o'clock  every  morn- 
ing the  fire  shutter  is  flicked  back,  the 
beam  is  released,  and  once  again  a  team 
of  crack  projectionists  is  off  on  the  first 
lap  of  its  regular  daily  routine — a  routine 
which  will  run  through  five  complete  pro- 
grammes and  will  cover  more  than  a  full 
round  of  the  clock. 

This  particular  scene  is  set  in  the  pro- 
jection room  of  The  Capitol,  Shaw 
Brothers'  palatial  1700-seater  cinema  in 
the  heart  of  tropical  Singapore.  Pro- 
jectionists accustomed  to  working  in  more 
temperate  climates  will  doubtless  view 
with  concern  the  thought  of  13  or  more 
hours  work  for  man  and  machine  under 
exacting  equatorial  conditions — but  this 
is  a  cinema  with  a  difference,  backed  by 
an  organization  that  is  progressive  al- 
most to  the  point  of  being  futuristic. 

The  machinery  is  the  most  modern  that 
the  industry  can  provide,  and  the  condi- 

gas  lamp  instead  of  a  shutter.  This 
gas  lamp  is  caused  to  flash  60  times  per 
second  by  a  special  power  source  known 
as  the  "pulsed  light  power  supply." 
Light  rays  from  this  type  of  system  have 
very  little  heating  effect  on  the  film;  in 
fact,  this  so-called  "cold  light"  in  the 
aperture  permits  stopping  the  film  and 
projecting  single  frames  without  the 
slightest  danger  to  the  film. 

A  cabinet  rack  houses  two  of  these 
power  supplies  as  well  as  a  monitor  and 
two  switching  panels. 


tions  under  which  the  staff  works  will  be 
the  envy  of  projectionists  the  world  over. 
The  "Box"  stretches  for  60-ft.  across  the 
entire  span  of  the  theatre,  and  with  a 
width  of  14-ft.  and  an  average  ceiling 
height  of  20-ft.,  it  must  rank  among  the 
most  spacious  of  projection  rooms.  The 
"Box"  is  air-conditioned  by  means  of 
large  vector  exhaust  fans. 

There  are  no  continuous  showings  in 
Malaya,  and  the  "Capitol"  has  a  staff  of 
four  projectionists  to  carry  through  its 
five  complete  programmes  each  day. 
Their  tour  of  duty  is  amicably  arranged 
by  the  senior  projectionists  in  order  to 
provide  adequate  coverage  for  each  show- 
ing and  reasonable  off-duty  time  for  the 
men. 

Craft  Welfare  Prime  Concern 

Staff  welfare  has  always  played  a  large 
part  in  maintaining  harmony  and  good- 
will in  the  Shaw  Brothers  organization — 
long-term  employees  predominate — and 
the  projectionists  enjoy  all  the  benefits 
of  a  comprehensive  welfare  scheme. 
Probably  the  most  important  feature  of 
the  scheme  is  the  provision  of  free  medi- 
cal attention,  and  in  a  country  where 
medical  services  are  of  necessity  expen- 
sive, it  is  much  appreciated  by  those  eli- 
gible to  use  it. 

Employees  of  the  firm  are  also  the  re- 
cipients of  a  handsome  yearly  bonus — - 

(Continued  on  page  30) 


12 


INTERNATIONAL  PROJECTIONIST 


May  1949 


The  Armat  Vitascope  which  projected  the 
first  theater  movie,  April  23,  1896. 


With  this,  the  "unseen  showman" 
got  his  epoch-making  start . . . 


THE  projectionist  has  come  a 
long,  long  way  .  .  .  since  the 
I890's  when  he  put  on  his  show 
with  equipment  such  as  this. 

And  today,  as  then,  much  of  a 
motion  picture's  success  depends 
upon  the  unseen  showman  in 
his  booth. 

To  his  sure  sense  of  split- 
second  timing  ...  to  his  alert 
control  of  sound  ...  to  his  deft 


handling  of  elaborate  equipment 
.  .  .  the  film  illusion  owes  much 
of  its  dramatic,  realistic  presen- 
tation on  the  screen. 

Helping  the  projectionist  to 
keep  the  mechanics  of  the  me- 
dium from  intruding  is  the  top 
quality  of  Eastman  motion  pic- 
ture films  (both  sight  and  sound)  . 
.  . .  members  of  a  famous  family 
started  more  than  fifty  years  ago. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.    Y. 

J.   E.   BRULATOUR,   INC.,   DISTRIBUTORS 
FORT    LEE     •    CHICAGO     •    HOLLYWOOD 


Psychological   Elements 


An  ardent  protagonist  of  rounded  screen  corners 
cites  the  reasons  for  his  attitude,  despite  the 
almost  universal  preference  for  square  corners. 


in    Projection 


THE  requirements  of  motion  picture 
screens  as  such  are  understood  suffi- 
ciently well  to  permit  recommenda- 
tions which  insure  satisfactory  projec- 
tion results  under  a  diversity  of  audi- 
torium conditions.  Unfortunately,  the 
same  cannot  be  said  of  the  psychological 
factors  which  surround  the  screen  and 
influence  its  effectiveness.  The  obscurity 
of  the  subject  has,  in  fact,  caused  many 
people  to  disparage  the  psychological 
aspect  of  projection  and  regard  the  pro- 
cess as  a  strictly  mechanical  reproducing 
medium  for  sight  and  sound. 

This  erroneous  point  of  view  tacitly 
denies  that  the  exhibition  field  has  any- 
thing to  do  with  motion  pictures  as  a 
medium  of  dramatic  expression. 

Observation  and  experience  give  rise 
to  very  different  opinions.  The  universal 
popularity  of  theatrical  motion  pictures 
is  due  almost  wholly  to  their  remarkable 
power  to  play  upon  the  emotions,  and 
that  the  average  patron  expects  an  emo- 
tional experience,  not  a  mere  succession 
of  animated  views.  We  are  therefore 
enabled  to  sense  the  existence  of  projec- 
tion factors  of  a  psychological  nature, 
even  though  we  have  no  means  of  weigh- 
ing or  measuring  them. 

Sense  of  Reality  Imperative 

The  secret  of  the  motion  picture  is  to 
be  found  in  the  mysterious  realm  of  the 
extrasensory.  We  are  required  to  recog- 
nize the  potency  of  intangible  emotional 
forces,  if  dramatic  films  are  to  be  suc- 
cessfully created  and  presented. 

The  screen  is,  accordingly,  much  more 
than  a  flat  surface  upon  which  pictorial 
elements  appear.  It  is  even  more  than  a 
window  through  which  magically  lifelike 
scenes  are  viewed.  The  screen  is,  in 
fact,   a   portal  through  which  the   audi- 


By  ROBERT  A.  MITCHELL 

ence  is  drawn  into  a  make-believe  world 
of  fascinating  illusion  where  events  and 
situations,  however  exaggerated  and  fan- 
tastic, seem  to  be  real. 

If  we  deny  this,  if  we  maintain  that 
a  motion  picture  is,  after  all,  nothing 
but  a  picture  and  that  the  screen  should 
mirror  events  in  coldly  accurate  tones 
because  no  glamorizing  medium  places 
rose-colored  glasses  before  our  eyes  in 
real  life,  then  we  should  not  complain 
when  the  public  tires  of  the  movies. 

The  projectionist's  function  in  the 
scheme  of  things  cinematic  is  vastly  more 
complex  than  most  people  realize.  He  is 
a  creator  of  "living  dreams".  The  tech- 
nique of  motion  picture  presentation  is 
just  as  much  a  part  of  the  projection  art 
as  oiling  a  projector  or  splicing  a  film. 
The  projectionist  is  a  technician,  to  be 
sure,  but  he  is  also  a  showman,  an  artist. 
All  his  mechanical,  optical,  and  electrical 
skills  are  directed  toward  the  production 
of  intangible  dramatic  effects. 

Psychological  Effect  of  Masking 

Now,  it  is  impossible  for  the  theatre 
patron  to  obtain  an  emotional  experience 
from  the  screen  unless  the  dramatic 
quality  of  the  picture  and  the  technique 
of  presentation  are  such  that  he  readily 
loses  himself  in  the  emotional  currents 
of  the  film.  This  means  that  all  factors 
which  distract  attention  from  the  them- 
atic atmosphere  of  the  picture  must  be 
eliminated  as  far  as  possible,  and  that 
the  framing  of  the  picture  must  be  such 
that  attention  is  naturally  drawn  away 
from  the  edges  of  the  screen  image  to 
the  center,  where  the  concentration  of 
mood   and  significant  action  is  greatest. 


The  first  matter  to  be  considered  in 
any  intensive  effort  to  improve  projection 
effectiveness  from  the  psychological  view- 
point is  the  problem  of  screen  masking. 
It  is  assumed  here  that  the  screen  sur- 
face, itself,  is  satisfactory,  and  that  the 
projection  itself  is  good. 

There  are  several  methods  of  masking 
screens.  Obviously,  one  of  these  methods 
is  correct,  and  all  the  others  are  wrong. 

The  prevalent  practice  of  masking 
screens  with  square  corners  is  open  to 
considerable  criticism.  It  violates  a  para- 
mount prerequisite  of  satisfactory  screen- 
image  framing  because  the  sharp  cor- 
ners have  a  strong  tendency  to  distract 
attention  (not  necessarily  direct  vision) 
from  the  central  areas  of  the  screen.  The 
corners  thus  act  as  reminders  to  the 
patron  that  he  is  observing  a  picture  on 
a  flat  surface  of  limited  area,  and  this 
effect  obtains  even  when  the  observer  is 
not  consciously  aware  of  it. 

Frequently  the  result  of  subconscious 
distraction  is  a  vague  restlessness  and  a; 
disturbing  wandering  of  the  thoughts, 
especially  during  long  scenes  having 
more  dialog  than  action.  In  the  course 
of  time  the  dissatisfied  patron,  associat- 
ing motion  pictures  with  discomfort  and 
boredom,  will  seek  more  diverting  forms 
of  entertainment. 

Sharp  corners  have  the  same  distract- 
ing effect  as  the  zig-zag  line  used  as  the 
conventional  symbol  of  electricity. 
Rounded  screen-image  corners,  on  the 
other  hand,  free  the  boundaries  of  the 
picture  from  all  attention-arresting' 
points.  By  the  use  of  rounded  corners 
vision  passes  naturally  to  the  central 
portions  of  the  picture  and  stays  there. 

Whether  or  not  a  round-cornered 
screen  "looks  better"  than  a  square- 
cornered  one  is  a  moot  point.    The  ap- 


FIG.  1.     Comparison  of  square-  and  round-cornered  screens  of  the  same  dimensions.     Rounded  corners 

are  advocated  in  the  belief  that  square  screen  corners  are  points  of  distraction  which  psychologically 

compete  with  the  projected  picture  for  the  attention  of  the  audience. 


14 


INTERNATIONAL  PROJECTIONIST     •     May  1949> 


Standard  Projector  Aperture 

Dimensions:  0.825  x  0.600" 

Corners:  0.047"   radius 

FIG.  2.    Standard   round-corner  aperture  plate 
of  the  slip-in  type. 

pearance  of  a  blank  screen  hardly  mat- 
ters, for  the  public  seldom  sees  a  theatre 
screen  "white".  The  important  thing  is 
that  a  round-cornered  screen  image 
greatly  facilitates  the  pc  tron's  absorption 
into  the  drama  of  the  picture. 

When  the  patron  "loses  himself"  in  a 
picture,  the  boundaries  of  the  image 
virtually  vanish  from  conscious  percep- 
tion. This  is  true  of  any  screen,  regard- 
less of  the  type  of  masking  used.  Psycho- 
logically speaking,  the  picture  becomes 
indefinitely  bounded.  Round-cornered 
screens  establish  this  desirable  effect  with 
remarkable  rapidity  and  succeed  in  main- 
taining it  satisfactorily  throughout  a  two- 
houre  show. 

Picture-Boundary  'Indefinition' 

The  phenomenon  of  picture-boundary 
"indefinition"  is  worth  considerable 
thought  because  it  has  been  objected 
that  a  round-cornered  screen  appears  to 
restrict  overall  area.  This  may  be  true 
when  blank  screens  are  viewed,  or  when 
a  round-cornered  picture  is  observed  mo- 
mentarily through  a  projection-room  port. 
The  effect  is  admittedly  variable  and 
slight. 

The  writer  fails  to  see  that  it  has  an 
adverse,  if  any,  effect  upon  the  patron. 
The  effect  of  a  round-cornered  screen 
image  is  such  that  the  picture  appears 
neither  larger  nor  smaller  than  a  square- 
cornered  picture  of  the  same  area.  Para- 
doxically, it  may  not  appear  to  be  the 
same  size,  either,  for  an  enhanced  bound- 
ary indefinition  blurs  or  dulls  the  con- 
sciousness of  definite  picture  area  in  the 
mind  of  the  engrossed  patron. 

The  well-known  perference  of  movie- 
goers for  seats  not  too  close  to  the  screen 
is  convincing  proof  that  physical  huge- 
ness is  undesirable. 

Figure    1,    sketched    from   the   projec- 


tion room  of  a  theatre,  shows  a  screen, 
the  same  size  in  both  instances,  before 
and  after  conversion  to  round-cornered 
masking.  When  one's  gaze  is  directed 
steadily  at  the  center  of  each  of  these 
screens  for  a  minute  or  two,  it  can  be 
seen  that  square  corners  impress  them- 
selves sharply  even  upon  averted  vision; 
while  rounded  corners  tend  to  "melt"  the 
boundaries  of  the  rectangle. 

Corners  having  larger  curves  would 
demonstrate  this  effect  more  readily,  but 
artistic  considerations  fix  the  radius  of 
the  corner  curves  at  1/16  the  width  of 
the  screen. 

The  actual  projection  of  pictures  indi- 
cates that  the  round-cornered  screen 
makes  the  flatness  of  a  two-dimensional 
picture  less  obvious.  Not  that  this  type 
of  screen  masking  produces  anything 
like  a  three-dimensional,  or  stereoscopic, 
effect,  but  it  confuses  the  screen  distance 
in  a  darkened  theatre  in  such  a  way  that 
the  observer  is  helped  to  overlook  the 
inherent  flatness  and  fixed  distance  of 
the  projected  scenes. 

Effect  on  Image  Steadiness 

Another  noteworthy  effect  of  round- 
cornered  screen  images  is  an  apparent 
reduction  of  image  unsteadiness.  Every 
now  and  then  a  defective  print  comes  our 
way.1  The  picture  sways  and  jumps  be- 
cause the  camera  was  poorly  supported 
oi  because  something  went  wrong  with 
the  printing  process.  In  such  instances 
any  "trick"  which  tends  to  minimize  the 
defect,  even  if  by  optical  illusion,  is  too 
valuable  to  pass  up. 

Many  theatre  men  make  the  mistake 
of  considering  round-cornered  screen  im- 
ages passe.  Historically,  round-cornered 
projector  apertures  were  universally  em- 
ployed until  square-cornered  screen 
masking  attained  its  present  position  of 
favor  only  because  of  the  ease  of  setting 
it  up.  A  few  exhibitors,  keenly  aware 
of  the  significance  of  many  seemingly 
small  details,  still  cling  bravely  to  the 
time-tried  round-cornered  picture;  but 
most  managements  slavishly  conform  to 
an  artless  "modern"  practice. 

Round-cornered  apertures  still  are 
standard  in  motion  picture  cameras.  Fig. 
2  shows  a  round-cornered  projector  aper- 
ture of  the  familiar  slip-in  type,  which  is 


1  See  "Factors  Affecting  Image  Steadiness"  in  IP  for 
January,  1948,  p.  5,  for  comprehensive  trouble-shooting 
measures. 


Insert 


Height  to  widtk 
in  ratio  3:4 


\ 


Corner  radius  =        J 
Vis    screen    width  * 


FIG.  4.    Suggested  method  for  masking  theatre  screen  with  rounded  corners. 


FIG.    3.     Proposed    standard    form    of    round- 
cornered   screen   image. 

used  in  conjunction  with  round-cornered 
screen  masking. 

The  psychological  importance  of  the 
form  of  the  projected  picture  asserted 
itself  strongly  during  the  period  of  con- 
version from  silent  to  sound  pictures. 
The  frames  on  35-mm.  silent  film  had  a 
height-to-width  ratio  of  approximately 
3:4.  The  addition  of  the  sound  track  al- 
tered the  proportions  of  the  frame  and 
resulted  in  a  picture  almost  square  in 
form. 

The  psychological  effect  was  so  bad 
that  technologists  restored  the  old  3:4 
silent  picture  ratio  by  diminishing  the 
height  of  the  frame.  It  is  difficult  to  ex- 
plain why  nothing  but  a  3:4-proportional 
screen  image  can  be  used  successfully  in 
a  motion  picture  theatre,  but  it  is  abso- 
lutely true. 

The  same  could  be  said  concerning 
rounded  corners,  for  they  provide  the 
most  satisfactory  framing  for  scenes  of 
all  types.  Fig.  3  illustrates  the  form  of 
what  the  writer  holds  is  the  correctly 
masked  screen.  The  height  and  width 
are  in  the  3 :4  ratio,  and  the  radius  of  the 
rounded  corners  is  1/16  the  width  of 
the  screen. 

Despite  the  almost  universal  use  of 
square-cornered  rectangles  for  screen  im- 
ages, the  popular  association  of  round- 
cornered  quadrilaterals  with  projected 
pictures  stubbornly  persists.  Nine  out  of 
ten  artists  who  depict  the  interiors  of 
motion'  picture  theatres  delineate  the 
screen  images  with  rounded  corners ;  and 
what  is  more,  they  intuitively  adopt  the 
most  desirable  corner  radius!  This  may 
be  explained  as  a  subconscious  prefer- 
ence for  that  type  of  screen  image,  and 
regarded  as  a  trustworthy  sampling  of 
public  opinion. 

Proper  Procedure  for  Masking 

The  actual  task  of  masking  a  screen 
with  rounded  corners  is  usually  very  sim- 
ple, but  it  calls  for  painstaking  work- 
manship. A  sloppy  masking  job  is  worse 
than  none. 

The  easiest  method  of  inserting  the 
corners  is  suggested  by  Fig.  4.  The  con- 
(Continued  on  page  28) 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


15 


IN  THE 


SPOTLIGHT 


By 

HARRY 

SHERMAN 


THE  widely-heralded  move  by  John  L. 
Lewis's  catch-all  District  No.  50, 
United  Mine  Workers  of  America,  to  gain 
control  of  theatre  employes  throughout 
the  country  was  checked  at  Philadelphia 
last  month  where  it  collided  head-on  with 
the  IA.  In  a  collective-bargaining  elec- 
tion conducted  by  the  Pennsylvania  Labor 
Relations  Board,  theatre  employes 
throughout  the  city  (cashiers,  doormen, 
ushers,  matrons,  cleaners  and  porters) 
gave  a  better  than  two-to-one  confidence 
vote  to  IA  Local  B-100,  which  had  rep- 
resented them  for  the  past  11  years.  The 
IA  victory  was  a  clean  sweep  among  the 
employes  of  three  theatre  circuits  and 
one  service  contractor.  District  No.  50 
sent  a  large  number  of  organizers  into 
the  Philadelphia  drive,  while  the  tightly- 
knit  IA  organizing  group  was  headed  by 
Larry  Katz,  International  representative. 
In  a  personal  letter  to  all  members  of 
Local  B-100,  President  Walsh  promised 
that  the  IA  would  fight  for  a  "fair  and 
adequate  wage  increase"  for  the  Phila- 
delphia theatre  employes,  and  that  an 
"absolute  condition"  of  any  final  settle- 
ment would  make  all  benefits  retroactive 
to  August  3  last. 

•  Pete  Mole,  president  of  the  Mole-Rich- 
ardson Company  on  the  West  Coast  and 


executive  vice-president  of  the  SMPE, 
is  on  a  three-months  European  tour 
through  England,  Switzerland,  France, 
and  Italy. 

•  The  first  inter-city  bowling  match  held 
recently  between  Detroit  Local  199 
(Nightingale  Club)  and  Cleveland  Pro- 
jectionists Local  160  resulted  in  a  victory 
for  the  Nightingales.  The  William 
Kramer  Trophy,  named  in  memory  of 
William  Kramer,  member  of  the  Cleve- 
land Local  who  died  shortly  after  these 
match  games  were  inaugurated,  now 
holds  the  place  of  honor  in  the  office  of 
Roger  M.  Kennedy,  Local  199  business 
manager. 

These  inter-city  bowling  matches  were 
sponsored  and  promoted  by  W.  Haartge 
and  Floyd  H.  Akins  of  Detroit,  and  R. 
Sheridan  and  Tom  Fitzgerald  of  Cleve- 
land. The  first  block  of  five  games  was 
rolled  in  Cleveland,  with  the  home  team 
scoring  a  54-pin  lead.  The  Detroit  team 
overcame  this  lead,  however,  by  scoring 
458  pins  on  the  return  match. 

The  Cleveland  bowlers  were  J.  Sobota, 
A.  Zill,  F.  Lane,  G.  Bullock,  and  T.  Smart 
on  Team  No.  1;  R.  Sheridan,  E.  Fitz- 
gerald, E.  Gehringer,  W.  Nobbe,  and  T. 
Fitzgerald,  made  up  Team  No.  2.  Play- 
ers for   the   Nightingale    Club   were   W. 


THREE  CHARTER  MEMBERS  OF  LOCAL  159,  PORTLAND,  ORE.,  STILL  ON  THE  JOB 


Forty-one  years  ago  20  men  affixed  their  signatures  to  the  charter  of  Local   159.    Shown  here 

(left  to  right)  are  three  of  these  original  signers  who  still  work  daily  at  the  craft:  Arthur  Phillips, 

Homer  Haynes  and  George  Grischow.    Gold  life  membership  cards  in  Local  159  were  presented 

these  three  veterans  by  President  L.  R.  Smith,  extreme  right. 


Fouchey,  E.  Waddell,  W.  Haartge,  J. 
Colwell,  and  R.  Thompson  on  Team  No. 
1 ;  E.  Douville,  R.  Haskin,  C.  Larsen,  M. 
Haskin,  and  G.  Light  played  on  Team 
No.  2. 

•  Otto  A.  Trampe,  54,  member  of  Mil- 
waukee Local  164  since  1919  and  its  busi- 
ness manager  for  the  past  four  and  one- 
half  years,  died  last  month  after  a  pro- 
longed illness.  During  the  past  30  years, 
Trampe  served  the  Local  in  many  official 
capacities  and  was  well-known  through- 
out the  Alliance.  He  was  an  active  and 
ardent  worker  in  the  labor  movement  and 
was  held  in  high  esteem  by  all  branches 
of  the  film  industry. 

Large  delegations  from  the  Chicago, 
Racine,  Kenosha,  and  Sheboygan  Local 
Unions  attended  the  funeral  services, 
which  were  held  in  the  Zion  Lutheran 
Church.  He  is  survived  by  his  widow,  a 
son,  Philip  (member  of  Local  164),  and 
two  daughters. 

•  Jottings  from  Local  623,  West  Palm 
Beach,  Fla.:  Johnny  Cummings,  secre- 
tary of  the  Local,  moved  into  his  new 
home  and  is  spending  his  leisure  time 
puttering  around  the  place.  .  .  .  James 
Bursey  was  the  delegate  to  the  State 
AF  of  L  Convention  held  recently  in 
Lakeland.  .  .  .  Charles  Crow,  business 
manager,  has  been  appointed  delegate  to 
the  forthcoming  7th  District  Convention. 
.  .  .  C.  C.  Dodds  is  the  proud-chested 
father  of  a  son — his  first-born.  .  .  .  Davey 
Day,  Chicago  Local  110,  is  still  hiber- 
nating on  the  sands  of  West  Palm  Beach, 
waiting  for  the  warm  breezes  to  hit  the 
Windy  City  before  departing  for  points 
north.  .  .  .  The  Local's  recent  annual 
banquet  was  voted  tops  by  the  members 
and  guests. 

•  One  of  the  more  pleasant  happenings 
during  the  past  month  was  a  telephone 
chat  with  P.  A.  McGuire,  whose  name 
looks  a  bit  strange  when  not  bracketed 
with  the  famous  slogan  "Better  Projec- 
tion Pays"  which  he  featured  for  so  many 
years  in  his  advertising  for  International 
Projector  Corp.  Mac  phoned  in  from  his 
home  in  Amityville,  L.  I.,  where  he  has 
been  making  steady  progress  in  recover- 
ing from  a  physical  setback.    He  is  very 


16 


INTERNATIONAL  PROJECTIONIST 


May  1949 


appreciative  of  the  many  messages  reach- 
ing him  from  his  host  of  friends  in  the 
craft. 

Although  Mac  has  been  enjoying  a  tele- 
vision set  for  many  weeks  now,  he  insists 
that  Tv  has  a  long  road  to  go  before  it 
can  compete  with  the  entertainment  value 
offered  by  the  motion  picture  theatre. 
More  than  ever  before,  says  Mac,  projec- 
tionists must  be  on  their  toes  to  keep 
their  equipment  up  to  snuff  so  as  to  pro- 
ject the  best  screen  image  possible. 
That's  Mac,  always  in  there  pitching. 

•  Wm.  P.  Covert,  business  manager  for 
Toronto  Local  173  and  second  IA  vice- 
president,  was  appointed  technical  ad- 
viser to  the  labor  delegate  attending  the 
32nd  session  of  the  International  Labor 
Conference  which  will  be  held  in  Geneva, 
Switzerland,  June  8  to  July  2  next.  Covert 
was  recommended  for  the  appointment  by 
the  Trades  and  Labor  Congress  of  Can- 
ada and  was  named  for  the  post  by  the 
Federal  Government.  Bill  sailed  on  the 
Aquitania  from  Halifax  May  17. 

•  New  York  City's  Fire  Commissioner, 
Frank  J.  Quayle,  takes  pride  in  the  fine 
fire  safety  record  of  his  city.  There  has 
not  been  a  single  loss  of  life  in  theatre 
fires  in  New  York  City  since  the  1890's, 
and  Quayle  attributes  this  to  the  splendid 
cooperation  between  the  theatre  owners 
and  the  public.  What  the  Commissioner 
failed  to  state  explicitly  is  that  the  two- 
man  operation  in  the  projection  rooms  of 
motion  picture  theatres  in  New  York* 
plays  a  major  role  in  keeping  theatres 
safe  for  the  movie-going  public. 

•  Two  vacancies  in  Milwaukee  Local 
164,  one  of  which  was  created  by  the 
death  of  its  business  manager,  Otto 
Trampe,  and  the  other  by  the  retirement 
of  George  Wittman,  treasurer  of  the 
Local  for  the  past  16  years,  were  filled 

NIGHTINGALES  WIN  KRAMER  1949  TROPHY 


NEW  BRUNSWICK,  N.  J.,  LOCAL  534  HONORS  TWO  ORIGINAL  MEMBERS  OF  UNION 


Roger  Kennedy  (left),  business  manager  for 
Detroit  Local  199,  accepts  the  William  Kramer 
Trophy  awarded  the  Detroit  Nightingales  in 
the  first  of  a  series  of  annual  bowling  matches 
with  Cleveland  Local  160.  Tom  Fitzgerald, 
president  of  the  Cleveland  Local,  assures  Ken- 
nedy that  the  return  match  in  1950  will  see 
the  trophy  back  in  Cleveland. 


Among  the  75  guests  at  the  party  were,  in  the  usual  order,  Eddy  Kane,  toastmaster;  Louis 
Marciante,  president,  N.  J.  State  Federation  of  Labor;  IA  President  Walsh,  who  presented  the 
gold  life  membership  cards;  Thomas  Coyne,  charter  member;  Pat  Rick,  president  Local  534; 
Thomas  Shea,  assistant  IA  president;  Thomas  V.  Green,  secretary  I A  14th  District;  and  Richard 

Fitz,  business  agent   Local   534. 


at  the  regular  election  held  last  month. 
Oscar  E.  Olson,  business  manager  of  the 
Local  from  1933  to  1944,  was  once  again 
elected  to  office,  and  George  Brader  was 
elected  secretary. 

The  news  of  Olson's  return  as  an  act- 


IA     ELECTIONS 


LOCAL  1,  NEW  YORK,  N  .Y. 

Joseph  Dwyer,  pres.;  George  Fitzgerald, 
vice-pres.;  John  C.  McDowell,  rec.-sec;  John 
J.  Garvey,  sec.-treas.;  Solly  Pernick,  John 
Goodson,  business  managers;  Louis  Yeager, 
tele,  organizer;  Jack  Shapiro  (chairman), 
John  Brousseau,  Frank  Kaiser,  board  of 
trustees;   E.  J.  Mortimer,  sgt.-at-arms. 

LOCAL   164,  MILWAUKEE,  WIS. 

Glenn  C.  Kalkhoff,  pres.;  Walter  Behr, 
vice-pres.;  Robert  Lucht,  rec.-sec;  Oscar  E. 
Olson,  bus.  rep.;  George  Brader,  treas.;  Au- 
gust Mommer,  sgt.-at-arms;  Myrl  Melton, 
trustee;  John  Black,  Norman  Habersat, 
Charles  Beggs,  Irvin  Rotter,  exec,  board; 
Oscar  Olson,  Glenn  Kalkhoff,  del.  Wisconsin 
State  Fed.  of  Labor;  Oscar  Olson,  Glenn 
Kalkhoff,  Robert  Lucht,  del.  IA  Convention. 

LOCAL  277,  BRIDGEPORT,  CONN. 

Roland  J.  McLeod,  pres.;  Frank  Toth, 
vice-pres.;  Leroy  Nickerson,  fin. -sec; 
Thomas  E.  Colwell,  rec.-sec;  John  A.  Mar- 
tin, bus.  rep.;  Fred  Lewis,  treas.;  John  C. 
Lynch,  sgt.-at-arms;  John  Benard,  Frank 
Gorman,  Harold  Ryckman,  Joseph  Cossette, 
Roland  McLeod,  Frank  Toth,  Leroy  Nicker- 
son, exec,  board;  Leslie  C.  Blakeslee,  Harry 
Kaplan,  George  Antoniak,  James  Liburdi, 
and  Joseph  Cink,  trustees.  Peter  Benard, 
John  Benard,  Roland  J.  McLeod,  Leroy 
Nickerson,  Joseph  Cink,  del.  Central  Labor 
Union;  John  Martin,  Roland  McLeod,  con- 
vention del.;  Frank  Toth,  Harold  Ryckman, 
alternates. 

LOCAL  324,  ALBANY,   N.  Y. 

Rocco  Memole,  pres.;  Eugen  Kelsey, 
vice-pres.;  Edward  E.  Wendt,  bus.  rep.; 
Charles  U.  Hill,  sec.-treas.;  Don  B.  Shepard, 
rec.-sec;  Samuel  Cooke,  sgt.-at-arms ;  George 
W.  Selley,  John  H.  Ray,  LeRoy  Lehr, 
trustees. 


ive  participant  in  Local  affairs  after  an 
absence  of  four  years,  during  which  time 
he  lived  on  the  West  Coast,  was  hailed 
by  the  members  who  have  benefited 
handsomely  in  the  past  by  Oscar's  adept 
handling  of  their  interests. 

•  We  mentioned  in  these  columns  last 
month  that  Sam  Bonansinga,  business 
manager  for  Local  138,  Springfield,  111., 
was  appointed  to  the  vice-presidency  of 
the  Illinois  State  Federation  of  Labor. 
We  neglected  to  state  that  Sam  is  the  first 
IA  man  to  hold  such  high  office  in  the 
Illinois  organization. 

•  An  inspiring  picture,  "The  City  of 
Hope,"  depicting  the  humanitarian  work 
carried  on  at  the  famous  tuberculosis 
sanatorium  at  Duarte,  Calif.,  was  shown 
at  a  meeting  last  month  of  the  delegates 
of  the  Central  Labor  Council  of  Los 
Angeles.  Charlie  Vencill,  secretary,  and 
Paul  Mahoney,  assistant  business  man- 
ager, Los  Angeles  Local  150,  supervised 
the  presentation,  and  Nick  Abdo,  mem- 
ber of  the  Local,  ran  the  film. 

•  Correction :  In  IP  for  April,  under  the 
heading  "IA  Elections"  (page  24),  we 
misspelled  the  name  of  Joe  A.  Campbell, 

MONKEYSHINES  IN   HOLLYWOOD 


Pat     Offer,     projection     chief     at     Monogram 

studios,  with  a  little  helpmate  at  the  preview 

screening  of  "Bomba." 


INTERNATIONAL  PROJECTIONIST 


May  1949 


17 


Al  Boudouris  of  Theu'fre  Equipment  Co.,  Toledo, 
Ohio,  contributes  this  shot  of  the  Century  pro- 
jector installation  at  the  Paramount  Theatre, 
Toledo.  Shown  are  projectionists  Francis 
Mclncrow,  Harold  Plumadore  (also  business 
agent  of  Local  228),  and  Harold  Neuart, 
electrical  engineer. 

member  of  the  executive  board  of  Local 
316,  Miami,  Fla.    Please  excuse  us,  Joe. 

•  Virus  X  bedded  our  good  friend  Jake 
Pries,  business  manager  for  Atlanta  Local 
225,  for  quite  a  spell.  No  sooner  had 
Jake  left  his  bed  than  the  very  person- 
able Mrs.  Pries  was  stricken  with  the 
same  malady.  Both,  we  are  happy  to  re- 
port, are  completely  recovered. 

•  Miami,  Fla.  boasts  of  having  one  of 
the  very  few  daylight  Masonic  Lodges  in 
the  country.  The  Meridian  Daylight 
Lodge  No.  274,  F  and  AM,  has  a  mem- 
bership composed  almost  entirely  of  men 
who  work  at  night,  with  meetings  being 
held  at  10  o'clock  in  the  morning.  The 
annual  installation  of  officers  is  held  at 
5  a.m.  each  December  27,  which  is  the 
beginning  of  the  Masonic  year.  Joe  A. 
Campbell,  executive  board  member  of 
Miami  Local  316,  is  secretary  of  the 
Lodge. 

•  Frank  Kinsore,  president  of  Detroit 
Local  199,  was  appointed  to  the  Michigan 
State  Fair  Board  of  Managers. 

•  Rudy  Knuer,  55,  died  on  May  6  after 
a  long  illness.  Rudy  was  associated  for 
more  than  30  years  with  the  manufacture 
and  sale  of  Simplex  Projectors,  first  with 
Peerless  Machine  Co.,  then  with  Inter- 
national Projector  Corp.,  and  finally 
with  National  Theatre  Supply  Co. 

Rudy  traveled  extensively  through  the 
United  States  and  Canada  on  behalf  of 
Simplex  and  thus  became  known  to 
thousands  of  projectionists  who  appre- 
ciated his  fine  technical  skill  no  less 
than  his  affable,  generous  nature.  He 
is  survived  by  a  daughter  and  by  a  son 
who  is  a  priest  of  the  Roman  Catholic 
church. 


First   Movie   Show   in   a   Theatre 

April  23  marked  the  53rd  anniversary 
of  the  first  exhibition  of  motion  pictures 
in  a  theatre.  That  evening  in  1896 
Thomas  Armat  operated  a  projector  of 
his  own  design  in  Koster  &  Bial's  Music 
Hall  in  downtown  New  York  City. 


Safety  Film  is  Now  1/6  of  All  Prints; 
Estimate  1/4  Level  by  Sept.  1 


RELIABLE  information  reaching  IP 
from  the  exchange  centers  through- 
out America  indicates  that  the  use  of  the 
new  Eastman  Safety  Film  (High  Acetyl 
Film  5302,  as  it  is  officially  designated) 
has  reached  such  proportions  as  to  con- 
stitute almost  one-sixth  of  the  total  num- 
ber of  release  prints  now  in  circulation. 
The  Safety  Film  figure  would  be  consid- 
erably larger  were  it  not  for  the  existence 
of  a  large  backlog  of  features  made  and 
for  which  prints  have  already  been  pro- 
vided. 

It  is  understood  that  Eastman  hopes  to 
provide  sufficient  Safety  Film  by  Septem- 
ber 1  next  to  increase  the  proportion  to 


one  out  of  every  four  of  the  total  number 
of  release  prints  then  in  circulation. 

The  introduction  of  Safety  Film  was 
attended  by  comparatively  little  difficulty, 
considering  the  many  complex  problems 
which  had  to  be  overcome.  Of  course, 
even  the  most  careful  advance  planning 
and  detailed  briefing  of  laboratory,  ex- 
change and  projection  personnel  did  not 
suffice  to  prevent  those  errors  which 
seemingly  are  unavoidable  in  any  project 
of  such  magnitude. 

The  labs  were  tripped  up  on  not  a  few 
occasions;  the  exchanges  made  the  ex- 
pected errors  of  improper  casing  and 
(Continued  on  page  27) 


INSTRUCTION   CHART   ON   SPLICING 


a  A  good  cine  splice  is  a  WELD  which  joins  two 
like  surfaces  together.  To  do  this,  the  film  base 
must  be  prepared  by  removing  the  layers  cover- 

' D   ing  it.  The  film  has  more  layers  than  is  com- 


monly known.  First,  there  is  the  emulsion  layer  A,  then  a  thin  invisible 
binder  layer  B,  which  binds  the  emulsion  to  the  base,  and  then  the  base 
itself  C  which  is  about  one  two-hundredth  of  an  inch  in  thickness.  The 
back  of  the  film  may  also  have  a  layer  D  of  oil  or  of  residue  from  proc- 
essing which  can  be  removed  by  delicate  scraping  or  by  wiping  with 
a  cloth  wetted  with  alcohol. 

GOOD  AND  BAD  SPLICES 

This  is  bad.  The  emulsion  has  not  been  removed 
completely. 

This  is  also  undesirable  but  may  hold  for  a 
while.  The  emulsion  has  been  removed  but  the 
invisible  layer  and  the  deposit  on  the  back  of  the 
film  remain. 

This  is  weak.  Careless  scraping  has  gouged  the 
film.  This  splice  will  eventually  break  in  this 
weakened  area. 

This  is  best.  Both  emulsion  and  invisible  layers 
have  been  removed  and  the  deposit  on  the  back 
scraped  away.  This  permits  a  perfect  weld  be- 
tween the  two  surfaces. 

Too  little  cement  causes  a  starved  joint  that  will 
soon  separate.  Inadequate  pressure  in  splicing 
also  produces  this  condition.   ■ 

Too  much  cement  makes  the  splice  buckle  and 
hence  produces  a  noticeable  effect  on  the  screen. 

In  splicing,  close  the  clamp  immediately  after 
applying  cement  to  the  scraped  portion.  A 
WELD  will  form  only  when  the  joint  is  wet. 

The  above  diagrams  show  the  film  thickness  exaggerated  to  a  much 
greater  degree  than  the  width  of  the  splice  for  purposes  of  illustration. 


Oo 


18 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


Optical  Factors  in  Arc  Lamp  Design 

This  exchange  of  views  between  author  and  manufacturer  is  in  line 
with  IP's  long-standing  policy  of  providing  a  forum  for  the  exchange 
of  views  between  anybody  and  everybody  having  anything  interesting 
to  say  anent  the  projection  process. 


By  J.  K.  ELDERKIN 

Forest  Manufacturing  Corporation 

IN  THE  article  "The  'Matching'  of 
Projector  Optics"  in  IP  for  Marchf,  it 
appears  to  me  that  the  author,  Robert  A. 
Mitchell,  has  not  considered  some  of  the 
practical  points  which  must  be  met  in 
lamp  and  projector  combinations. 

In  order  to  obtain  maximum  light  from 
a  lamp  and  projector  lens  system,  one 
must  start  from  the  aperture  and  work 
back  from  there.  A  35-mm  film  aperture 
is  26  mm  across  diagonally,  therefore  the 
spot  diameter  must  be  more  than  26  mm 
or  the  corners  of  the  screen  will  be  very 
dark  and  discolored.  The  spot  must  over- 
lap the  corners  of  the  aperture  suffi- 
ciently to  give  some  semblance  of  even 
light  distribution.  The  greater  the  spot 
size,  the  more  even  will  be  the  light  dis- 
tribution. 

Correlating  the  Various  Factors 

Let  us  assume  that  the  spot  diameter 
should  be  32  mm  ±  in  diameter  for 
suitable  light  distribution.  The  next  step 
is  to  arrive  at  a  magnification  ratio  to 
reduce  the  size  of  the  spot,  since  the 
diameter  of  the  crater  X  the  magnifica- 
tion ratio  give  spot  diameter. 

The  crater  of  the  carbon  is  approxi- 
mately 23/32,  or  0.719  X  the  carbon 
diameter.  Assuming  that  a  9-mm  carbon 
is  being  used,  the  crater  diameter  is  6.47 
mm,  then  the  magnification  ratio  must 
be  5  to  obtain  the  32  mm  —  spot. 

We  now  have  two  things  fixed:  spot 
diameter  and  magnification  ratio.  The 
next  thing  requiring  consideration  is 
how  close  to  the  reflector  can  the  arc 
burn  without  injury  to  the  former.  By 
cut-and-try,  we  find  that  a  75-  to  90- 
ampere  arc  must  be  burned  at  a  distance 
from  the  reflector  of  from  61/2  to  7  inches 
to  prevent  cracking. 

This  condition,  then,  sets  for  us  the 
equivalent  focus  of  the  reflector.  With 
7  inches  as  the  equivalent  focus,  our 
working  distance  is  set,  because  the 
magnification  ratio  X  the  effective  focus 
equals  the  working  distance;  or  5  X  7 
equals  35  inches,  which  is  our  working 
distance. 

We  now  have  working  distance,  effec- 
tive focus  and  magnification  ratio  deter- 
mined for  us  by  the  nature  of  the  equip- 
ment. The  only  thing  left  that  is  vari- 
able, then,  is  the  diameter  and  depth  of 
reflector  and  its  F  speed. 

Since  working  distance  is  already  fixed 


at  35  inches,  as  cited  previously,  then 
the  diameter  of  the  reflector  X  the  de- 
sired speed,  plus  the  reflector  depth, 
must  equal  35  inches.  Assuming  16 
inches  for  the  diameter  of  the  reflector 
and  a  speed  of  F:  2,  then  16  X  2  equals 
32,  which  means  that  the  depth  of  the 
reflector  must  be  3  inches  to  make  the 
35-inch  working  distance. 

Suppose  we  were  to  use  a  12-inch 
diameter  reflector  with  a  speed  of  F:  2.5 
— then  the  reflector  depth  would  have  to 
be  5  inches.  On  the  other  hand,  where 
we  want  a  speed  of  F.T.5  with  a  12-inch 
reflector,  its  depth  would  have  to  be  too 
great  to  be  practical.  On  the  basis  of 
F:1.5,  reflector  diameter  must  be  in- 
creased greatly  to,  say,  20  inches,  and 
then  a  5-inch  depth  could  be  used. 

The  point  to  all  this  is  that  we  must 
have  a  certain  size  spot,  we  must  keep 
the  arc  a  certain  distance  from  the  re- 
flector, we  must  hold  to  a  practical  work- 
ing distance  in  order  to  place  the  lamp 
behind  the  projector  with  front  shutters, 
we  cannot  make  reflectors  larger  than 
will  fit  into  a  lamp,  etc. 

We  are  thus  left  with  just  a  few  factors 
which  are  variable  and  these  are  limited 
by  practicability.  We  can  only  hope  to 
produce  the  greatest  possible  light  at 
the  aperture. 

Speed  of  Objective  Lens 

The  same  holds  true  for  the  objective 
lens,  which  should  be  selected  to  take 
advantage  of  the  light  from  the  reflector 
without  overcrowding.  There  are  limita- 
tions here,  also,  based  on  practical  con- 
siderations, but  if  the  same  formula  be 


used  as  is  used  for  the  reflector,  it  makes 
no  difference  whether  you  call  its  F-speed 
0.5,  1.6,  2,  or  any  other  number.  The 
point  is  that  they  should  match  each 
other  insofar  as  is  practical. 

A  new  formula  does  not  change  the 
mechanics  of  light  transmission,  which 
have  been  pretty  well  proven  with  the 
passage  of  time. 

By  ROBERT  A.  MITCHELL 

THE  information  contained  in  Mr. 
Elderkin's  most  interesting  letter  has 
little  bearing  on  the  principles  of  lamp- 
projector  optical  matching  which  formed 
the  main  subject  of  my  article;  but  con- 
sidered as  an  addendum  to  that,  Mr. 
Elderkin's  comment  serves  to  emphasize 
the  various  practical  considerations  by 
which  the  unwary  may  easily  be  ensnared. 
The  statement  that  lamp  manufacturers 
"cannot  make  reflectors  larger  than  will 
go  into  a  lamp"  injects  an  element  of 
humor  into  the  discussion. 

The  procedure  by  which  any  manufac- 
turer "roughs  out"  a  tentative  lamp 
optical  system  merely  sets  the  stage  for 
the  really  tough  problems  to  follow.  Had 
I  intended  to  offer  a  review  of  these 
matters  in  the  article  in  question,  I 
should  certainly  have  mentioned  some  of 
the  paramount  problems  which  folloiv 
the  elementary  preliminaries  outlined  by 
Mr.  Elderkin. 

Light  Distribution  Vital  Factor 

That,  however,  was  not  my  intention,, 
hence  I  do  not  consider  that  I  am  in  any 
way  guilty  of  ignoring  "some  of  the 
practical  points  which  must  be  met  in 
lamp  and  projector  combinations."  And 
if  that  had  been  my  intention,  I  would 
have  concentrated  attention  on  projec- 
tion lenses,  rather  than  lamps. 

Now  that  the  subject  has  been  intro- 
(Continued  on  page  25) 


t  Page  7. 


NATIONAL  THEATRE  SUPPLY  CO.  EASTERN  MANAGERS  DISCUSS  NEW  PRODUCTS,  METHODS 


Jn  the  usual  order: 
Jack  Servies,  district 
supervisor  and  pur- 
chasing agent;  H.  J. 
McKinney,  Boston; 
A.  F.  Baldwin,  export 
manager;  R.  W.  Pries, 
Philadelphia.  Seated: 
W.  J.  Hutchins, 
Albany -New  Haven; 
Allen  Gordon  Smith, 
New  York;  N.  C. 
Haefele,  Baltimore; 
V.  G.  Sanford,  Buf- 
falo; and  W.  J.  Turn- 
bull,  sales  promotion 
manager. 


INTERNATIONAL  PROJECTIONIST 


May  1949 


19 


NBC  Advises  Exhibitors 
of  Tv  Facilities  Available 

ALTHOUGH  the  National  Broadcast- 
ing Co.  will  not  permit  the  use  of 
its  Tv  program  material  on  the  large 
screens  of  motion  picture  theatres  with- 
out a  specific  license,  the  network  places 
no  barriers  on  the  use  of  home  receivers 
in  theatre  lounges  or  lobbies,  Charles  R. 
Denny,  executive  vice-president,  has  in- 
formed the  Theatre  Owners  of  America. 

In  addition  to  a  clarification  of  this 
long-confused  issue,  Denny  told  the  TOA 
that  three  principal  types  of  Tv  pro- 
grams were  potentially  available  for 
large-screen  theatre  exhibitions  when 
licensed.     These  included: 

Three  Principal  Program  Types 

(1)  programs  which  NBC  might  build 
specially  on  order  from  the  theatres  for 
their  primary  use;  (2)  special  event  pro- 
grams which  form  part  of  NBC's  Tv 
programming  and  are  not  normally  spon- 
sored, such  as  a  Presidential  inaugura- 
tion or  an  important  public  address;  and 
(3)  NBC's  regular  Tv  programs  which 
are  sponsored  by  advertisers  or  are 
carried  on  a  sustaining  basis. 

"Only  the  first  category  of  programs, 
those  which  NBC  might  build  on  order 
from  theatres,  might  be  made  available 
for  exclusive  theatre  use,"  Denny  de- 
clared. "In  the  other  two  categories,  the 
broadcast  use  would  be  the  primary  use 
made  of  the  material  although  where 
NBC  controlled  or  could  clear  all  rights, 
arrangements  might  be  made  in  appro- 
priate cases  for  simultaneous  or  subse- 
quent showing  in  theatres." 

A  condensation  of  RCA's  answers  to 
the  TOA's  queries  follows: 

Will  NBC  provide  the  necessary  equipment  for 
theatre  Tv  screening? 

Barton  Kreuzer  of  RCA  Victor,  informs 
me  that  RCA  is  now  taking  orders  both  for 
the  instantaneous  or  direct  projection  equip- 
ment for  theatres  and  also  for  the  35-mm 
film  storage  equipment.  These  two  types 
of  equipment  for  theatre  Tv  will  be  avail- 
able in  limited  numbers  by  the  end  of  this 
year. 

Terrific  First  Cost  Foreseen 

Is  it  possible  to  approximate  the  cost  of  such 
theatre  installations? 

Mr.  Kreuzer  also  advises  me  that  the 
estimated  cost  of  the  instanteous  or  direct 
projection  equipment  is  about  $25,000,  not 
including  the  cost  of  external  relay  equip- 


ment, pickup  cameras,  or  the  expense  of 
installation.  The  cost  of  35-mm  film  storage 
equipment  is  variable,  depending  upon  the 
particular  type  of  installation  required,  but 
this  equipment  runs  higher  in  price  than 
the  instantaneous  equipment. 
Will  NBC  make  available  to  exhibitors  special 
sport  and  national  events  (such  as  Inaugura- 
tion) which  it  carries  on  either  sustaining  or 
other  basis  to  its  affiliates? 

Where  NBC  owns  or  can  clear  all  of  the 
rights  for  theatre  showing  of  programs  of 
special  sporting  and  national  events,  it 
would  be  prepared  in  appropriate  cases  to 
license  theatres  to  use  these  programs  for 
theatre  showings.  In  cases  where  NBC  is 
one  of  a  group  of  broadcasters  originating 
the  program,  NBC  could  not  make  commit- 
ments for  the  other  broadcasters,  and  any 
arrangements  for  theatre  showing  would 
have  to  be  made  with  the  group. 

Commercials  To  be  Included 

Where  the  program  is  sponsored,  as  for 
example  in  the  case  of  the  major  football 
games,  the  commercial  announcements  would 
have  to  be  included  in  the  material  shown 
by  the  theatre,  and  the  advertiser's  consent 
would  have  to  be  obtained. 
Will  service  be  made  available  to  any  and  all 
exhibitors  who  want  it  or  will  it  be  on  the  same 
basis  that  NBC  has  its  present  affiliates? 

In  the  case  of  programs  built  by  NBC 
specially  on  order  for  theatre  showings,  it 
should    be    possible    to    grant    the    theatres 

PROJECTION    IN  THE  ANTIPODES 


Comparing  favorably  with  America's  best  is 
this  projection  room  in  the  Regent  Theatre, 
Melbourne,  Australia.  Complete  installation 
by  Wcstrex,  including  Australian-made  arc 
lamps  of  indubitable  American  design  much 
like  the  Peerless. 


ordering  the  special  program  an  exclusive 
license  for  its  use.  In  the  case  of  programs 
created  primarily  for  Tv  broadcasting,  and 
available  for  theatre  showing,  it  would  not 
be  NBC's  policy  arbitrarily  to  exclude  any 
theatre  which  desired  to  make  arrangements 
for  a  license  from  NBC,  from  access  to  this 
material. 

On  what  basis  would  NBC  make  its  charges? 
The  fee  which  NBC  would  charge  the 
theatres  would  be  such  as  to  cover  its  ex- 
penses attributable  to  providing  the  pro- 
grams to  the  theatre,  plus  a  fair  profit  to 
NBC.  The  fee  would  vary  depending  on 
the  type  of  program  and  theatre  involved, 
and  initially,  at  least,  would  be  subject  to 
negotiations  in  each  case. 

Transmission  Means  Suggested 

What  mechanical  means  will  be  used  for  the 
transmission   of  programs  to  the  theatres? 

Where  theatres  are  sufficiently  close  to 
the  source  of  transmission  of  a  show  origi- 
nated by  NBC  for  broadcast  purposes,  direct 
pickup  of  the  broadcast  by  the  theatre  is 
possible,  with  NBC's  consent.  I  am  sure 
that  you  are  familiar  with  the  study  theatre 
operators  have  given  to  the  possibility  of 
using  coaxial  cable  or  radio  relay  circuits 
where  direct  pickup  is  not  feasible. 
Will  the  programs  made  available  to  the 
theatres  be  sponsored  by  advertisers? 

Presumably,  the  programs  created  spe- 
cially for  theatres  would  not  be  commercially 
sponsored.  As  indicated  previously,  if  ar- 
rangements were  made  with  the  advertisers' 
consent  for  showing  by  theatres  of  regular 
commercial  Tv  programs  for  which  the 
necessary  rights  had  been  cleared,  the  pro- 
grams as  shown  in  the  theatre  would  have 
to  carry  the  associated  commercial  announce- 
ments. 

*       *       * 

Predicts  100%  Theatre  Tv 

"As  surely  as  they  converted  to  sound  in 
the  1930's,"  all  exhibitors  eventually  will 
equip  their  theatres  for  showing  Tv  pro- 
grams on  their  screens,  Paul  Raibourn, 
Paramount  vice-president,  predicts  in  an 
article  in  Elks  Magazine  for  April. 

Expense  of  such  a  move,  Raibourn  said, 
will  be  justified  by  the  "best  guarantee  or 
protection  in  the  world — the  assurance  that 
human  nature  does  not  change.  Everything 
in  life  is  better  when  it  is  shared,  particu- 
larly an  emotional  experience." 

Arguing  that  Tv  will  not  hurt  the  theatre, 
but  can  be  put  to  work  for  it,  Raibourn 
declared,  "I'll  go  a  step  further  and  even 
venture  to  suggest  that  Tv  may  make  the 
neighborhood  movie  house  of  the  future  the 
community  center  and  focal  point  of  public 
opinion." 


20 


INTERNATIONAL  PROJECTIONIST 


May  1949 


Addendum  to  SMPE  Screen  Brightness  Report 


POINTING  up  the  more  significant  as- 
pects of  the  report  of  the  Screen 
Brightness  Committee  of  the  SMPE  (pub- 
lished in  IP  for  March,  1948,  p.  16, 
under  the  heading  "Wide  Variance  in 
Screen  Light  Levels")  is  the  appended 
discussion  which  followed  formal  presen- 
tation of  the  report  to  the  Convention. 
Procedural  methods  and  equipment  used 
are  detailed  in  this  discussion,  along 
with  the  opinions  of  various  members 
who  have  had  wide  experience  in  the 
light  projection  field. 

Q.  Has  the  Committee  established  what 
would  be  a  desirable  screen  brightness  for 
theatres? 

A.  The  present  standard  is  9  to  14  foot- 
lamberts  as  measured  at  the  center  of  the 
screen,  with  the  projector  running  but  no 
film  in  the  gate.  Whether  that  standard 
will  be  changed  I  am  not  prepared  to  say. 

SMPE  Standard  Ultimate  Aim 

Q.  The  concerns  that  sell  equipment  are 
not  equipped  to  advise  a  man  who  contem- 
plates building  a  theatre  and  comes  to  the 
supply  house  for  advice.  They  don't  seem 
to  know  just  what  results  will  ensue  from 
a  different  throw  in  a  house  of  given  size, 
for  one  thing.  "Why  should  they  not  know 
this  basic  information? 

A.    By  finding  out  the  present  practice  in 


theatres,  by  proper  measuring  instruments, 
and  by  knowing  what  each  piece  of  equip- 
ment will  deliver,  it  will  be  a  natural  evolu- 
tion that  that  sort  of  thing  will  occur:  the 
equipment  in  the  theatre  will  be  matched 
to  meet  the  SMPE  standards. 

Q.  Knowledge  of  the  surrounding  bright- 
ness is  very  important  in  interpreting  the 
data  you  have  given.  Is  there  any  intent 
on  the  part  of  the  Committee  to  gather  data 
on  the  screen-brightness  level,  excluding  the 
projected  light? 

A.  That  is  part  of  the  longer-range  objec- 
tive of  the  Committee,  but  it  has  not  been 
a  part  of  the  immediate  progTam.  The 
initial  phases  are  aimed  mainly  at  deter- 
mining what  methods  and  equipment  should 
be  used  to  measure  brightness  and  illumina- 
tion and  to  determine  present  practice. 
Some  of  those  other  things  we  all  hope 
will  come  along  a  little  later  in  the  program. 

Q.  I  assume  that  during  the  course  of 
your  survey  you  did  not  visit  any  studios. 
Do  you  intend  to  do  so? 

A.  Not  at  present.  The  main  intent  is 
to  determine  the  practice  in  theatres. 

Basic  vs.  Operational  Defects 

Q.  There  was  one  point  on  which  I  was 
not  exactly  clear.  You  mentioned  that  50 
of  the  theatres  were  getting  75%  of  the 
available  light.  Do  you  mean  that  there 
were    misadjustments   in   the    equipment   or 


do  you  mean  that  the  equipment  was  rated 
at  a  higher  rating  than  the  theatre  actually 
was  using? 

A.  Data  have  been  published  indicating 
the  total  quantity  of  light  that  could  be 
expected  from  various  combinations  of  arcs 
and  optical  systems.  Those  data  were  taken 
into  consideration  along1  with  the  exact  pro- 
jection equipment  in  the  theatre.  The  Com- 
mittee did  not  investigate  why  that  differ- 
ence occurred. 

Screen  Characteristics  Vital 

Q.  The  factor  of  the  screen  itself  and  the 
light  coming  from  it  represent  additional 
items  that  are  elusive.  I  wonder  if  this 
report  will  include  that  eventually?  One  is 
the  age  of  the  screen;  two,  the  location  of 
the  screen,  the  atmospheric  condition;  three, 
the  polar  characteristic  of  the  screen. 

Unless  we  investigate  all  these  things,  the 
changing  factor  of  what  you  are  getting  off 
that  screen  is  amazing.  Unless  we  add 
those  data,  we  do  not  know  what  actually 
is  getting  to  the  people's  eyes. 

A.  The  age  of  the  screen  with  its  condi- 
tion was  not  specifically  investigated.  The 
Committee  went  into  the  theatre  and  meas- 
ured what  the  condition  was  at  the  moment. 
Whether  it  was  a  new  screen  or  an  old,  a 
dirty  screen  or  a  clean  screen,  was  not  con- 
sidered. 

With  reference  to  the  condition  of  the 
atmosphere:  since  all  these  measurements 
were  made  without  any  people  in  the  house, 
I  suppose  we  could  assume  that  the  atmos- 


For  Screen  Images  .  .  . 

As  The  Camera  Took  Them 


THE  more  you  close  the  gap  between  the 
critically  precise  camera  image  and  the  pro- 
jected image  on  your  screen,  the  better  your 
presentations,  and  box  office  receipts,  will  be. 
That  is  exactly  what  the  Bausch  &  Lomb  Super 
Cinephor  projection  lens  is  designed  and 
built  to  do.  You  can  retain  all  the  original 
beauty  of  fine  detail,  subtle  tone,  and  brilliant 
color  of  your  films  by  replacing  your  old 
lenses  with  Bausch  &  Lomb  Super  Cinephor 
lenses.  Bausch  &  Lomb  Optical  Co.,  616-E  St. 
Paul  St.,  Rochester  2,  N.  Y. 


BAUSCH  &  LOMB 


OPTICAL  COMPANY 


ROCHESTER  2,  N.  Y 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


21 


pheric   conditions   were   best. 

We  expected  to  consider  the  polar  charac- 
teristic, and  we  still  hope  that  the  infroma- 
tion  we  have  will  show  that.  You  recall 
the  slide  on  which  was  shown  where  and 
how  the  brightness  was  measured.  The 
brightness  reading  was  taken  at  the  center 
of  the  screen  and  at  the  upper  left-  and 
lower  right-hand  corners,  from  four  extreme 
positions  in   the  theatre. 

When  we  have  sufficient  information  avail- 
able from  a  more  intensive  survey,  all  of 
those  data  can  be  analyzed  to  tell  what  is 
the  polar  characteristic  of  the  screen.  While 
the  indications  are  not  definite,  they  tend 
to  show  that  the  screens  all  were  matte  and 
had  a  fairly  uniform  reflectivity  within  the 


angles  encountered  in  the  particular  theatres 
surveyed. 

Brightness  vs.  Film  Density 

Q.  What  brightness  is  best  for  different 
density  conditions  of  film,  or  what  lambert 
will  produce  the  best  contrast  value  for  dis- 
cerning image  detail?  The  light  values  alone 
will  not  give  us  the  ultimate  answer  unless 
we  have  tests  made  with  actual  film  strips. 

A.  That  point  is  realized,  but  the  Com- 
mittee chose  to  consider  first  things  first. 
One  of  the  basic  unknowns  was  the  present 
value.  Once  that  is  determined,  our  activity 
can  be  enlarged  to  include  such  very  per- 
tinent  questions  as  you  have  raised. 

Q.    Will  not  that  affect  the  recommended 


IMPART 


TO  YOUR 


PRESENTATIONS 


TUE  CTDAIIft  TDAIID 

HE  SI  KUNu  1  KUUr 


A.  C.  CARBON  ARC  SPOTLIGHT 


Produces   a    sharp,   snow-white,    uniformly  arc    voltage,    for   the    first    time    making 

illuminated    spot    far    surpassing    in    bril-  possible    a    high    intensity    arc    spotlight 

Nancy    any    incandescent    or    vertical    arc  without  the  use  of  heavy  rotating  equip- 

spotlight,  and  equalling  many  large  thea-  ment. 

tre  type   spotlights  ...   a   light  such   as  Automatic  arc  control  maintains  constant 

is  obtainable  only  with  high  intensity  arcs.  arc    gap    ana    „    sready    light,    free    from 

Easily  operated.  hiss  or  flicker.     A  trim  of  carbons  burns 

Employs    a    silvered    glass    reflector    and  one  hour  and  20  minutes  at  21   volts  and 

two-element    variable    focal    length    lens  ^5  amperes. 

system.  Horizontal   masking  control.    Can  be  an- 

Draws  only  10  amperes  from  any  110-volt  3led    «*    45    degrees    in    each    direction. 

A.C.    convenience    outlet.    A    highly    effi-  Color  boomerang  contains  six  slides  and 

cient,    adjustable,    self-regulating    trans-  ultraviolet  filter  holder. 

former  which    is   an    integral   part  of  the  Mounted  on  casters.    Easily  disassembled 

base  reduces  the  current  supply  to  a  low  for  shipping. 

Use  coupon  to  obtain  literature,  prices  and  name 
of    nearest    independent    theatre    supply    dealer. 

Please  send  free  literature,  prices  and  name  of  the 
nearest  dealer  in  Strong  Spotlights. 

NAME      

COMPANY 

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TOLEDO   2,   OHIO  CITY   and   STATE 


THE 

STRONG 

ELECTRIC  CORP. 

"The  World's  Largest  Manu- 
facturer of  Projection 
Arc  Lamps" 


foot-lambert  measurement? 

A.  It  probably  will  if  it  is  demonstrated 
by  proper  tests  that  the  standards  should 
be  changed.  Right  now  the  standards  are 
9  to  14  foot-lamberts. 

Q.  Could  you  give  us  a  little  more  detail 
as  to  the  type  of  instrument  with  which 
you  measured  the  brightness? 

A.  That  was  a  Luckiesh-Taylor  visual 
photometer. 

.  .  Q.  I  am  not  familiar  with  that.  Can  you 
tell  definitely  what  part  of  the  screen  you 
are  looking  at  when  you  look  through  the 
instrument?     Is  it  a  focused  image? 

Sectors  of  Screen  Measured 

A.  You  can  use  either  a  view-finder,  which 
we  did  in  some  instances,  or  by  locating  on 
the  screen  at  the  same  time  some  one  is 
measuring  illumination  with  a  photronic 
cell,  it  is  possible  to  tell  where  you  are  on 
the  screen,  and  knowing  the  angle  of  ac- 
ceptance of  the  instrument  and  the  distance 
you  are,  you  can  tell  what  portion  of  the 
screen  you  are  actually  measuring  when  you 
are  measuring  brightness. 

Q.  I  assume,  then,  you  did  not  use  the 
Weston  instrument  that  is  available  to  a  lim- 
ited extent  right  now? 

A.    For  measuring  brightness? 

Q.   Yes. 

A.    I  am  not  familiar  with  that  one. 

A.  It  is  a  foot-lambert  meter  which  has 
been  put  out  on  a  small  scale. 

Q.  Based  upon  the  wide  variance  of  per- 
centages that  you  found  existing  in  different 
theatres,  would  you  not  come  to  the  con- 
clusion that  possibly  a  great  deal  of  the 
fault  is  based  upon  the  poor  quality  or  out- 
moded use  of  the  screens  and  the  projection 
equipment  used. 

A.  I  do  not  think  the  Committee  has 
done  enough  to  take  any  stand  at  all  on 
that. 

Q.  Because  of  the  wide  variance  in  your 
percentages  found — in  some  cases  your  re- 
sults were  of  a  high  degree  and  in  a  great 
many  cases  they  were  of  low  degree — you  can, 
therefore,  come  to  but  one  conclusion:  either 
the  screens  were  old,  dirty  and  outmoded, 
or  the  light  projected  from  the  projection 
room  was  not  adequate. 

A.  Certainly  if  you  are  investigating  the 
basic  reasons  for  those  things  which  were 
discovered,  you  have  two  factors  to  consider : 
what  light  is  projected  to  the  screen  and 
what  is  reflected.  On  a  very  broad  generali- 
zation, the  reasons  why  the  brightness  was 
not  up  or  why  the  light  intensity  was  not 
what  it  might  have  been  have  to  be  attrib- 
uted to  one  or  the  other.  That  was  not 
determined  in  this  survey. 

Q.  I  quite  understand  that,  but  I  think 
it  would  be  the  object  of  your  Commmittee 
to  find  out  whether  or  not  the  equipment 
in  use  in  the  theatres  of  the  country,  screens, 
projection  equipment,  light  sources,  and 
everything  involved  needs  replacing  and  can 
very  well  stand  it. 

Point-to-Point  Measuring 

Q.  I  notice  that  the  projection  distance 
was  measured  from  the  aperture  to  the 
screen.  I  have  always  considered  that  this 
distance  was  measured  from  the  front  sur- 
face of  the  lens  nearest  the  screen  to  the 


22 


INTERNATIONAL  PROJECTIONIST 


May  1949 


screen  itself.  The  lens  constitutes  the  last 
light  source  in  the  optical  train. 

Inasmuch  as  the  foot-candles  on  the 
screen  are  determined  absolutely  by  the 
brightness  of  the  lens  and  the  lens  area, 
the  effective  lens  area — which  varies  in- 
versely as  the  square  of  the  distance — the 
discrepancy  becomes  somewhat  larger.  Why 
was  the  distance  chosen  as  being  from  the 
aperture  to  the  screen? 

A.  It  is  more  a  question  of  saying  that 
it  was  from  the  aperture  to  the  screen, 
rather  than  a  specific  measurement.  The 
determination  of  that  distance  was  made  by 
measuring  from  the  screen  to  the  point  in 
the  theatre  on  a  parallel  under  which  we 
estimated  the  projector  to  be,  and  then 
calculating  from  the  projection  angle  what 
the  actual  distance  was. 

I  am  quite  sure  that  those  figures  are 
not  accurate  to  better  than  six  inches;  but 
even  considering  the  shortest  throw,  an  error 
of  plus  or  minus  six  inches  will  not  be 
more  than  1%. 

Q.  I  brought  the  question  up  merely  for 
the  sake  of  accuracy,  because  the  projection 
distance  is  actually  measured  from  the  last 
lens  in  the  system,  which  is  the  distance 
from  the  lens  to   the   screen. 

Reflection  Factor  of  Screen 

The  second  point  is  related  to  the  rela- 
tively low  values  of  reflection  for  these 
screens.  Was  that  reflection  factor  deter- 
mined on  the  basis  of  an  integrated  effect 
over  an  appreciable  area  of  the  screen 
which  took  into  account  the  screen  perfora- 
tions, or  was  that  intended  to  represent  the 
coefficient  of  reflection  of  the  screen  surface 
itself — tli-t  is.  the  reflecting  efficiency  of  the 
screen  surface? 

A.  That  was  determined  by  taking  the 
ratio  of  the  brightness  measured  at  the 
center  of  the  screen  to  the  light  intensity 
at  the  center  of  the  screen.  The  brightness- 
measuring1  instrument  probably  did  not  in- 
clude more  than  an  area  of  from  one  to  two 
square  feet.  It  certainly  took  into  considera- 
tion if  there  were  holes  in  the  screen  as  it 
existed   in  the  theatre  at  the  center. 

Q.    It  was  an  integrated  effect? 

A.  For  a  small  area  at  the  center  of  the 
screen. 

Q.  There  again  the  actual  coefficient  of 
the  reflection  of  the  screen  surface  would 
be  higher  than  is  shown. 

A.   You  mean  of  the  unperforated  screen? 

Q.    That  is  right. 

A.    I  expect  that  it  would  be. 


BOOK     REVIEW 


Sound  Track  Book  of  the  Theatre:  a 
compendium  of  articles  which  have  appeared 
from  time  to  time  in  "The  Sound  Track," 
merchandising  organ  for  Motiograph  deal- 
ers. 445  pages,  6%  x  9%,  profusely  illus- 
trated, including  color  plates,  indexed.  The 
Sound  Track,  1001  West  Washington  Blvd., 
Chicago  7,  or  Motiograph  dealers.    $10. 

Those  who  have  read  "The  Sound  Track," 
promotional  organ  for  products  distributed 
by  Motiograph  dealers,  are  very  familiar 
with  the  type  of  technical  articles  contained 


sijpi:i!-s\iii'MTi: 


SEALED 
HERMETICALLY 


,  ONE-PIECE 
MOUNT 


ANODIZED 
FINISH 


COATED 
'  OPTICS 


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gftte 


%fe 


&>. 


IF  THE  SPEED  OF  THE  LAMP  IS  SLOWER  THAN  THE  LENS, 

WHY  USE  A  FAST  LENS? 

This  is  answered  in  detail  in  an  article  by  Dr. 
J.  L.  Maulbetsch  in  the  "International  Projec- 
tionist" of  September,  1947.  In  brief,  a  fast  lens 
gives  more  uniform  illumination  because  hav- 
ing larger  lens  elements  it  picks  up  more  of  the 
edge  illumination  than  a  slower  lens  with  corre- 
spondingly smaller  lens  elements. 

ARE  ADAPTERS  NECESSARY  FOR  SNAPLITE  LENSES? 

Fittings  are  available  to  adapt,  where  neces- 
sary, Snaplite  lenses  to  all  currently  manufac- 
tured professional  projectors. 


WHERE    CAN 
OBTAINED? 


DRAWINGS    OF    THESE    ADAPTERS     BE 


The  required  adapters  are  shown  on  the  last 
page  of  Kollmorgen  bulletins  204  and  206. 
These  bulletins  are  available  at  your  theatre 
supply  dealers.  Dimensions  of  all  adapters  ex- 
cept the  shade  tube  are  fixed.  The  length  of  this 
shade  tube  varies  with  the  focal  length  of  the 
lens. 

HOW  MANY  LENS  ELEMENTS  ARE  THERE  IN  A  SUPER- 

SNAPLITE? 

Six — two  pairs  of  elements  are  cemented  to- 
gether and  two  elements  are  single. 

ARE  THE  CEMENTED  SURFACES 
COATED? 

No — treating  cemented  surfaces  with 
an  anti-reflection  coating  would  not  in- 
crease the  light  transmission  of  the 
lens. 

"You  Get  the  Most  Uniform  Light  with  Super-Snaplite" 

i:oi,M\oir<;fx    /      %% 

\^ofaa/  C0ltl>0lt  ATION 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


23 


in  this  volume.  Non-readers  will  understand 
that  the  bulk  of  the  articles  concern  Motio- 
graph  products,  but  the  foreword  states  that 
"the  models  described  incorporate  basic 
principles  of  design,  so  that  a  knowledge  of 
their  construction  and  operation  will  be 
found  applicable  in  nearly  all  cases." 

As  so  it  is,  particularly  with  respect  to 
those  articles  relating  to  the  principles  of 
sound  reproduction.  The  book  is  divided 
into  three  main  sections:  projection  and 
sound,  theatre  management  and  maintenance, 


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safety  cut-off  .  .  .  when  i/oor  ojiens 
or  film  breaks,  motor  stojis. 

Available  thru  Leading 
Theatre  Supply  Dealers 

Send  for  Bulletin  No.  456 


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and  recent  developments — the  latter  treating 
of  drive-in  theatres,  television,  and  stereo- 
phonic sound. 

Despite  its  almost  exclusive  concern  with 
Monograph  products,  this  volume  consti- 
tutes a  worthy  addition  to  the  technical 
literature  in  that  it  offers  rock-bottom  data 
on  the  basic  principles  of  visual  and  aural 
projection.  Particularly  effective  are  the 
large-scale  illustrations  in  both  line  and 
halftone  which  are  an  invaluable  aid  to  the 
text.  Especially  is  this  true  of  the  color 
plates,  which  are  models  of  clarity  and  pre- 
cision.' 

While  not  much  of  this  material  may  be 
said  to  be  revelatory  by  reason  of  its  new- 
ness, such  a  compendium  under  one  cover  of 
the  basic  principles  of  the  art  deserves  a 
cordial  reception  and  a  wide  distribution. 


PERSONAL     NOTES 

William  B.  Lodge,  vice-president  in 
charge  of  engineering  for  Columbia  Broad- 
casting System,  has  been  named  to  the 
Board  of  Governors  of  the  SMPE,  marking 
the  first  time  in  history  that  a  television 
engineer  has  been  so  designated. 

John  F.  Campbell,  for  some  time  vice- 
president  in  charge  of  production  for  Inter- 
national Projection  Corp.,  has  joined  the 
Luna  Metal  Craft  Co.,  Inc.,  as  operating1 
vice-president.  A  subsidiary  company,  Ro- 
An  Devices,  has  been  formed  to  manufacture 
motion  picture  devices  and  equipment. 

Western  Electric  Co.  has  announced  the 
appointment  of  Paul  L.  Palmerton  as  act- 
ing director  of  public  relations,  effective 
May  1.  He  will  succeed  Fred  B.  Wright  as 
director  of  this  activity  when  the  latter 
retires  on  May  31. 

E.  Allan  Williford  has  resigned  as  vice- 
president  and  general  manager  of  the  Ansco 
Division,  General  Aniline  &  Film  Co.  Willi- 
ford formerly  was  head  of  carbon  sales  for 
National  Carbon  Co.,  is  a  past  president  of 
the  SMPE  as  well  as  of  TESMA.  Future 
plans  not  announced. 


New  W.E.  16-mm  Rerecorder 

A  new  16-mm  rerecorder  designed  to  pro- 
vide the  basic  qualities  of  35-mm  equip- 
ment, has  been  made  available  to  its  licen- 
sees by  Erpi  unit  of  Western  Electric. 
Mounted  in  rack  type  cabinets,  the  ma- 
chines   may    be    placed    in    rows    for    easy 


/^BLK§080®l\ 

ALL   METAL 

PI 

IJMIguTO 

\2\1 17  Lb  15  (S  u  C°)  \w 

GUARANTEED  5  YEARS 

Manufactured  by 

HEYER-SHULTZ,  Inc. 

MONTCLAIR,  N.  J. 

^TatTona^I 

E,  Kimwi"""  M    ! 

access  and  pleasing  appearance.  The  film- 
pulling  mechanism  is  similar  to  that  used 
in  W.  E.  recording  equipment  and  reduces 
flutter  to  a  maximum  of  ±  .06%  total  or 
±  .04%  at  any  given  rate.  No  free  loops 
are  used  in  threading.  Correct  threading  is 
assured  by  a  small  target  which  causes  a 
black  line  to  be  centered  in  a  circular  open- 
ing when  the  correct  sprocket  hole  is  en- 
gaged. 

Reels  up  to  the  1600-foot  size  may  be  ac- 
commodated, with  ample  space  remaining 
for  manipulation  and  threading  without  con- 
gestion. The  lower  section  of  the  upright 
cabinet  is  available  for  mounting  such  equip- 
ment as  lamp  and  high-voltage  power  sup- 
plies. The  rear  of  the  cabinet  is  reached 
by  a  hinged  door  for  access  to  equipment. 
Openings  at  the  top  allow  for  film  exit  and 
the  use  of  an  overhead  loop  rack.  Motor 
driven    rewind    facilities   are    also    provided. 


Probe  'Aerial  Oxidation' of  Compounds 

How  some  chemical  compounds  "burn" 
or  are  oxidized  at  ordinary  room  tempera- 
tures is  explained  in  a  recent  paper  by  Dr. 
Arnold  Weissberger  of  Eastman  Kodak's 
synthetic  organic  research  laboratory.  His 
paper  is  entitled  "Recent  Developments  in 
Science". 

Dr.  Weissberger  said  that  "while  most  or- 
ganic compounds  burn,  or  are  oxidized,  at 
higher  temperatures,  some  chemical  com- 
pounds are  attacked  by  the  oxygen  of  the 
air  at  ordinary  room  temperatures".  Such 
oxidation  is  of  great  biological  importance. 
And  in  photographic  processing,  he  said,  it 
causes  waste  because  it  uses  up  the  chemi- 
cals with  which  the  film  is  developed. 

The  first  clue  as  to  how  "aerial  oxida- 
tions" of  some  of  these  compounds  proceed 
was  obtained  in  1927  through  chance  ob- 
servation.     "Since    then,"    said    Dr.    Weiss- 


LE  ROY  J.  FURMAN— In  charge 
of  operations  "Monarch"  Division, 
Gamble  Enterprises,  Inc.,  New  York, 

N.  Y. — says: 

"We  have  just  extended  our 
RCA  Service  agreement,  and 
included  Projection  Room 
Parts.  We  believe  it  is  a  good 
investment." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


24 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


berger,  "the  rate  of  a  number  of  oxidations 
has  been  studied.  The  compounds  studied 
include  the  most  important  photographic  de- 
veloping agents  and,  also,  compounds  such 
as  Vitamin  C".  From  this  research  scien- 
tists understand  better  the  effect  of  many 
of  the  compounds  and  how  to  avoid  oxida- 
tion waste. 


Kodak's  New  W  Film  Emulsion 

A  new  photographic  emulsion  developed 
io.r  identifying  atoms  or  chemicals  through 
analysis  of  their  radiant  energies  may  prove 
useful  for  study  of  the  sun  from  rockets, 
'.'.he  new  material,  called  a  "vacuum  ultra- 
violet" or  VU  emulsion,  may  be  used  in  the 
thin  atmosphere  250  miles  or  more  above 
tlie  earth,  or  in  near-vacuum  on  the  ground. 
ft  is  sensitive  to  light  far  into  the  ultra- 
violet. 

This  VU  emulsion,  developed  by  Eastman 
Kodak,  has  extremely  close-packed  silver 
grains,  with  very  little  gelatin.  The  gelatin 
cf  a  normal  photo  emulsion  absorbs  ultra- 
violet light.  The  new  emulsion,  with  little 
gelatin,  enables  the  ultraviolet  light  to  be 
recorded.  Ultraviolet  rays  of  the  sun  are 
intense  at  high  altitudes  where  the  VU 
emulsion  may  be  used.  While  the  sun's  rays 
in  this  form  cannot  penetrate  the  atmos- 
phere, study  of  them  is  important  because 
they  occasion  changes  in  our  weather  and 
radio  communications  facilities. 


Supersonic  Speed   Plus  via  Silver 

In  your  change  pocket  it's  a  dime —  "token 
money,"  metal  worth  less  than  six  cents. 
Treat  it  chemically  and  spread  it  thin — a 
thousandth  of  an  inch  or  less — and  it  be- 
comes a  miracle  metal,  as  silver  nitrate,  the 
foundation  of  photography.  Research  sci- 
entists and  engineers  who  have  gone  on 
refining  the  performance  of  this  light-sensi- 
tive substance  now  report  new  miracles  in 
speed. 

Film  now  is  made  which  will  record  an 
image  with  a  light  exposure  of  one-millionth 
of  a  second!  Also,  there  are  high-speed  mo- 
tion picture  cameras  which  will  take  up  to 
20,000  frames  per  second! 

These  speed  twins,  based  upon  one  of 
silver's  many  industrial  uses,  vastly  improves 
many  kinds  of  motion  analysis  studies,  im- 
portant to  research,  engineering  and  indus- 
trial operations.  Slow-motion  this  lightning- 
speed  stuff  and  it  becomes  possible  to  study 
many  things  heretofore  unobservable  and 
unknown. 


Return  to  Nomenclature  Normalcy 

Recent  industry  and  public  discussions  of 
Tv  assignments  have  demonstrated  the  con- 
fusion and  futility  of  such  terms  as  "Very 
High  Frequency"  and  "Ultra  High  Fre- 
quency" in  today's  ever-widening  electro- 
magnetic spectrum.  Such  comparative  defi- 
nitions have  already  become  meaningless 
and  should  be  dropped  from  any  further  use. 

To  avoid  further  confusion,  let's  get  back 
to  the  absolute  and  specific,  such  as  "50-MC," 
"500-MC"  and  similar  numerical  delineations 
that  will  leave  no  doubt  as  to  what  we  are 
talking  about!—  Tele-Tech. 


OPTICAL-ARC  FACTORS 

{Continued  from  page  19) 

duced,  what  are  some  of  the  really  prac- 
tical considerations  in  lamp  design?  Mr. 
Elderkin  mentions  efficiency  (maximum 
light  output),  and  his  entire  outlined 
procedure  indicates  well  how  that  end 
may  be  achieved.  ("We  can  only  hope 
to  produce  the  best  reflector  possible 
within  these  limitations  and  thus  produce 
the  greatest  possible  light  at  the  aper- 
ture.") 

No  mention  is  made  of  the  kind  of 
light  aimed  at,  the  distribution  of  light 
over  the  aperture  area.  Of  course  we 
want  efficiency  in  a  lamp,  but  we  also 
want  much  more. 


Projectionists  should  understand  that 
there  is  vastly  more  to  the  "figuring"  of 
mirror  curvature  than  simply  specifying 
mirror  "depth"  in  inches  or  centimeters. 
There  are  all  types  of  "curves"  available 
to  the  designer — the  simple  conic  sec- 
tions, such  as  the  circular,  the  elliptical, 
the  parabolic,  and  the  hyperbolic;  and 
the  not-so-simple  curves,  such  as  those 
utilized  in  the  Schmidt  compensating 
lens  system. 

Mirror  the  Heart  of  System 

We  naturally  do  not  expect  manufac- 
turers of  arc-lamp  mirrors  to  complain 
(as  if  they  were  telescope  makers)  if 
their  mirrors  deviate  from  perfect  form 
by  a  few  wave-lengths  of  violet  light,  but 


Meet  your  demand  for 

HIGH  INTENSITY  PROJECTION  and 
UNIFORM  SCREEN  ILLUMINATION 

'  wit h 

HERTNER  Type  CPlF 


Drive-in  and  deluxe  theatres,  large  auditoriums  and 
halls  must  have  plenty  of  light  on  the  screen  with 
uniform  illumination.  That's  why  the  Hertner  CP 
Transverter  is  so  popular  with  such  operators.  This 
Transverter  gives  you  these  advantages: 

1.  Range  of  capacities  3.  High  intensity 

2.  Close  voltage  regulation       4.  Uniform  screen  illumination 

Demand  equipment  that  gives  you  these  advantages. 
Specify  the  CP  Transverter.  For  complete  information 
consult  your  nearest  National  Theatre  Supply  dealer. 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


25 


ROBERT  H.  URLING  — Owner 
and  Operator,  Wayne  Theatre, 
Wayne,  West  Virginia — says: 

"The  theatre  I  operate  is 
small  but  I  know  that  I  can 
compete  with  the  biggest  and 
best  by  using  RCA  sound 
and  service." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


we  do  expect  sound  scientific  design. 
And  because  the  mirror  is  the  heart  of  a 
projection  lamp,  we  expect  a  lamphouse 
to  be  designed  for  a  specified  type  of 
mirror,  not  the  mirror  for  the  lamphouse. 

'Hot-Spot',  Vignetting  Effect 

Mr.  Elderkin  mentions,  by  way  of 
illustration,  the  crater  diameter  of  a  cer- 
tain high-intensity  carbon.  From  this 
quantity  he  determines  the  magnification 
ratio  required  to  give  a  spot  of  prede- 
termined size.  Well  and  good.  But  what 
is  not  mentioned  by  him,  however,  is  the 
fact  that  the  intensity  of  illumination 
varies  very  considerably  across  the  face 
of  a  high-intensity  crater,  the  brilliance 
being  greatest  at  the  center.  As  I  pointed 
out  near  the  end  of  my  article,  corrective 
optics  are  necessary  to  overcome  a  seri- 
ous hot-spot,  or  vignetting,  effect.  The 
same  point  is  brought  out  by  Mark 
Stevens'  article  in  the  same  issue  of  IP.J 

One  may  profitably  inquire,  therefore, 
if  a  given  lamp  mirror  is  so  inexpertly 
"figured"  that  a  light-wasting  oversized 
spot  is  necessary  in  order  to  obtain  a 
reasonably  uniform  field  of  light  on  the 
screen.  A  mere  "semblance"  of  uniform 
screen  illumination,  to  use  Mr.  Elder- 
kin's  own  term,  is  not  enough. 

Performance  is  measureable,  optimum 
performance  is  assignable,  and  perform- 
ance in  the  field  is  the  real  criterion  for 
any  commercial  device.  Performance, 
let  it  be  added,  has  qualitative  as  well 
as  quantitative,  aspects. 

Mr.  Elderkin  is,  of  course,  correct  in 


t  "Total   Lumens    vs.    Screen    Light   Distribution,"    by 
Mark   Stevens;    IP    for   March,    1948,    p.   20. 


200-Inch    Palomar   Telescope   Joins 
Photography  in  Epochal  'Shots' 

Even  the  power  of  a  million  human  eyes 
falls  short  of  that  of  the  new  Hale  Telescope 
atop  Mt.  Palomar  in  California.  The  200- 
inch  telescope  is  really  a  huge  camera — 
the  world's  biggest — and  it  has  the  strength 
which  photography  alone  can  give  it. 

In  theory,  the  "big  eye"  has  the  light-gath- 
ering power  of  a  million  human  ones.  Actu- 
ally, the  telescope  is  far  better  than  this 
would  suggest.  Why?  Because  the  photo- 
graphic plates  used  in  the  telescope  can: 
be  exposed  for  long  times — hours,  if  needed 
— to  catch  light  human  eyes  would  never 
see;  make  lasting  records;  provide  "observa- 
tions" for  many  people  to  see  and  study. 

Kodak  is  now  making  special  photoplates 
for  use  in  the  48-inch  Schmidt  telescope, 
which  will  work  in  partnership  with  the 
200-incher  at  Palomar.  Other  Kodak  plates 
will  be  used  in  the  Hale  telescope  when  it 
gets  into  operation  in  future  months. 

The  first  five-year  task  for  the  Schmidt,  or 
"Big  S,"  will  be  to  map  the  universe.  The 
main  use  of  the  Hale  telescope  will  be  to  col- 
lect the  faint  light  from  very  distant  stars. 
Its  "range"  is  a  billion  light  years.  A  light 
year  is  the  distance  light  travels  in  one  year 
at  186,000  miles  a  second — or  about  six 
trillion  miles. 


stating  that  "a  new  formula  does  not 
change  the  mechanics  of  light  transmis- 
sion." The  "new"  general  formula  for 
matched  optics  which  I  set  forth-  for  the 
convenience  of  projectionists  pays  ac- 
ceptable homage  to  the  geometric  prin- 
ciples of  light  transmission,  and,  like  any 
other  law  of  nature,  it  does  not  command 
that  something  shall  take  place  but  only 
states  how  something  happens. 

The  general  formula  permits  any  type 
of  lamp  to  be  designed,  good  or  bad, 
and  it  also  allows  any  spot  diameter  to 
be  used:  it  has  nothing  to  do  with  those 
matters.  I  feel  that  projectionists  are 
under  no  misconception  in  regard  to  the 
general  formula.  It  is  a  searchlight  to 
reveal  the  deficiencies  of  various  lamp 
and  projector  combinations.  Only  those 
who  would  say  that  there  is  no  room  for 
improvement  in  projection  optics  can 
logically  deny  this. 

Applicable  to  All  Optical  Systems 

The  general  formula  applies  to  all 
motion  picture  lamp  optical  systems  re- 
gardless of  the  diameter  of  the  mirror, 
the  working  distance,  and  the  geometric 
focus.  It  instantly  reveals  any  iailure  of 
a  projector  optical  system  to  meet  the 
requirements  of  perfect  optical  match- 
ing. Indeed,  this  may  sometimes  be  an 
embarrassing  revelation,  but  in  no  wise 


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86   SHIPMAN    STREET      •      NEWARK  2,  N.  J. 


26 


INTERNATIONAL  PROJECTIONIST 


May  1949 


does  it  reflect  unfavorably  upon  any  lamp, 
no  matter  how  unsound  its  design  or 
poor  its  performance. 

All  that  the  general  formula  discloses 
is  the  simple  fact  that  in  most  cases  the 
lamp  system  and  the  lens  are  unsuited  to 
each  other.  This  "optical  incompata- 
bility"  results  in  a  poorly  and  unevenly 
illuminated  picture  on  the  screen,  and 
the  defect  is  ordinarily  corrected  by 
changing  the  lens,  not  the  lamp. 

The  problems  connected  with  the  de- 
signing of  projection  lenses,  Mr.  Elder- 
kin's  statement  to  the  contrary,  are  in  no 
sense  strictly  analogous  to  those  involved 
in  mirror  design. 

Discussions  Serve  the  Art 

Of  course,  I  had  rather  be  100%  wrong 
than  to  have  no  attention  whatever  paid 
to  these  extremely  important  matters  by 
the  manufacturing  end  of  the  industry. 
Far  from  bristling  and  opposing  the  pub- 
lication of  such  data,  manufacturers 
should  enter  into  the  true  spirit  of  the 
occasion  and  cooperate  wholeheartedly 
in  an  effort  to  effect  improvement — for 
their  own  sakes  as  well  as  for  the  good 
of  projection  generally. 

I  personally  feel  that  the  welfare  of 
the  projection  craft  is  being  served  ad- 
mirably by  these  open  discussions  and 
little  controversies.  After  all,  no  fair- 
minded  person  wishes  to  hide  the  truth. 


SAFETY  PRINTS  INCREASE 

(Continued  from  page  18) 

marking,  not  to  mention  the  inevitable 
quota  of  defective  splices;  while  the  pro- 
jectionist craft  had  its  troubles,  particu- 
larly in  that  period  preceding  the  joint 
Eastman-IP  educational  program  which 
pretty  effectively  blanketed  the  theatre 
field  down  to  the  smallest  crossroads 
operation  with  precise  data  anent  the 
handling  of  the  new  stock. 

Despite  this  fine  educational  job  the 
pronounced  upsurge  of  Safety  Film  in 
the  theatre  field  (no  less  than  the  demon- 
strated truth  of  the  old  adage  that  one 
needs  not  so  much  to  be  told  as  re- 
minded) makes  it  advisable  to  reiterate 
those  salient  features  relating  to  the 
proper  handling  of  acetate  stock  by  the 
projectionist — and,  for  that  matter,  by 
the  exchanges. 

The  matter  of  attaining  a  satisfactory 
splice  with  Safety  Film  revolves  around 
the  twin  factors  of  a  proper  film  solvent 
and  correct  operational  procedure.  Since 
the  proper  solvent  is  now  generally  avail- 
able, the  only  remaining  consideration  is 
correct  procedure.  Bearing  on  this  point 
is  the  accompanying  instruction  chart 
which  not  only  conveys  data  relative  to 
the  fundamental  structure  of  the  film 
support  but  also  details  correct  splicing 
procedure. 

A  razor  blade  is  not  considered  to  be 


a  desirable  splicing  tool.  Its  use  creates 
rather  than  diminishes  splicing  trouble. 
Of  major  importance  is  the  condition  of 
the  splicer  used.  On  the  Griswold  splicer, 
for  example,  make  sure  that  the  center 
bar  (shear  plate)  is  not  etched,  because 
such  etching  will  tend  to  tear  the  corners 
of  the  film. 

Scraping  Blade  Replacement 

Highly  important  is  the  frequent  sub- 
stitution of  a  fresh  scraping  blade.  The 
blade  on  a  Griswold  splicer  may  be  turned 
frequently  to  offer  eight  different  scrap- 


ing surfaces.  About  25  scrapings  per  sur- 
face is  the  maximum  number  that  should 
be  made  before  the  blade  is  turned.  When 
all  eight  surfaces  have  been  utilized 
(200  scrapes)  a  new  blade  should  be  in- 
serted. Spare  blades  should  always  be 
on  hand. 

It  is  advisable  to  work  from  the  center 
of  the  film  frame  toward  each  edge, 
rather  than  to  make  one  continuous 
scrape  the  width  of  the  frame,  so  as  to 
avoid  those  errors  shown  in  the  accom- 
panying chart.  After  the  emulsion  has 
been  removed,  be  sure  to  scrape  off  the 


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Stan  fien£o>u*t<z*tce   with  STAR  CORE 

/ 
i 

£ 

JiorVtA^ tank**  A 

fV       ^^^k 

ra            '^H 

STAR  CORE,  exclusive  feature  with  the           J^taUfEIE X*TTt  .n=       fc*    \  \ 

Lorraine   Carbons  —  a   manufacturing               Ihrouohoul  the  world  ate  Lorraine  Corboni.           tei    _Jj    \ 

process  that  increases  the  performance                 •Feoiured  in  our  horizontal-food                     tHkv^ 
of  the  carbons.                                                 c.po.r.c.ot.d  corb.n.. 

A  more  brilliant,  steadier,  more  con-                w»"f  f°«  distribution  data 
sistent white  light — more  economically                PADRfiWC      INP                              A 
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ai,lons-                                                               NEW  YORK:  234  WEST  44U.  STREET                         \ 

■■-»»    WITHflNY     LAMP      IN  ANY  SIZE     THEATRE 

•^  J? 

INTERNATIONAL  PROJECTIONIST 


May  1949 


27 


invisible  binder  layer  (B  in  the  chart) 
until  the  rough  white  surface  of  the  base 
evidences  no  gloss  by  reflected  light.  It 
is  especially  important  that  the  area 
around  the  perforations  and  at  the  ends 
be  perfectly  clean. 

After  the  shearing  operation,  lift  the 
splicer  clamp  just  a  trifle  to  permit  ap- 
plication of  the  cement,  thus  keeping  the 
plate  as  clean  as  possible.  Apply  the 
cement  in  one  firm,  continuous  stroke 
with  the  brush,  as  opposed  to  a  "lather- 


M.  M.  MESHER— District  Mana- 
ger, Hamrick-Evergreen  Theatres, 
Portland,  Oregon — says: 

"RCA  Service  is  dependable 
and  we  have  found  it  to  be 
most  valuable  for  the  excel- 
lent   operation    we    always 
strive  to  maintain." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


ing"  up-and-down  motion  which  involves 
the  use  of  excess  cement  and  will  only 
cause  trouble,  usually  a  "bumpy"  patch. 

Application  of  Pressure  Vital 

Once  the  cement  is  applied,  it  is  im- 
portant that  the  pressure  clamp  be 
brought  down  immediately:  lower  it 
slowly  but  firmly  instead  of  with  an 
abrupt  clamping-down,  which  tends  to 
splash  the  cement  and  thus  thicken  the 
splice. 

Hold  the  pressure  clamp  down  for  not 
less  than  10  seconds:  additional  time  will 
not  compensate  for  previous  procedural 
errors  in  terms  of  effecting  a  stronger 
bind.  Upon  releasing  the  pressure 
clamp,  wipe  off  any  excess  cement  from 
the  splice  itself  and  from  the  center 
splicer  bar. 

The  removal  of  the  sub-layer  (see  B 
in  chart)  is  somewhat  more  critical  on 
Safety  than  on  nitrate  base  and  requires 
close  attention  on  the  part  of  the  pro- 
jectionist. Duplitized  film,  whether  Safe- 
ty or  nitrate,  has  emulsion  on  both  front 
and  back  surfaces  and  is  much  more 
difficult  to  splice  than  single-coated  stock. 
All  duplitized  film  stock  (Trucolor,  Mag- 
nacolor,  Cinecolor,  etc.)  must  have  both 
sub-bases  scraped  on  both  ends  of  the 
film  to  be  spliced  before  a  secure  join 
can  be  made. 

Important:  Always  examine  the  edge- 
markings  of  all  film,  features  or  shorts, 
before  projection,  so  as  to  distinguish  be- 
tween Safety  and  nitrate  stock.  Buy  the 
smallest  available  quantity  of  film  ce- 
ment at  one  time  so  as  to  insure  constant 
freshness.  Keep  the  cement  bottle  cov- 
ered at  all  times  when  not  in  use. 


nuunRp  unnnER 

Flutter  Suppressor  Wins 
ACADEMY   AWARD! 


The  Academy  of  Motion  Picture  Arts  &  Sciences  recog- 
nized the  value  of  this  development  in  making  its  1947 
award  to  C.  C.  Davis  of  the  Western  Electric  Co. 

CENTURY  can  give  you  this  outstanding  improvement 
in  sound  reproduction   NOW. 


The  Award- 
winning  Hydro 
Flutter  Suppressor 
as  used  in  the 
new  Century 
sound  reproducer. 


Improve  the  perform- 
ance qualify  in  your  theatre  —  see 
your  dealer  or  write  for  information. 

CENTURY  PROJECTOR  CORP 

New  York,  N.  Y. 


Century  Sound  Reproducer 


PSYCHOLOGICAL  ELEMEKTS 
IN   PROJECTION 

(Continued  from  page  15) 
struction  of  the  masking  frame  deter- 
mines whether  the  inserts  are  placed 
before  or  behind  the  battens.  Trial  cor- 
ner inserts  may  be  cut  from  dead-black 
cardboard  and  used  for  several  weeks,  if 
desired,  while  the  matter  of  a  permanent 
fitting  is  being  considered.  Attention  to 
the  following  points  is  imperative. 

(1)  The  corner  inserts  must  have  smooth 
quarter  curves  absolutely  identical 
one  with  another. 

(2)  The  radius  of  the  curvature  must  be 
exactly  1/16  screen  width.  (Divide 
the  screen  width  expressed  in  inches 
by  16,  or  else  multiply  screen  width 
in  inches  by  0.0625  to  obtain  the 
same  result.) 

(3)  The  blackness  and  "deadness"  of 
the  inserts  should  match  the  rest  of 
the  masking. 

(4)  Standard  round-cornered  apertures 
must  be  installed  in  the  projectors. 
(These  are  readily  procurable,  and 
the  cost  is  trifling.) 

In  most  cases  the  permanent  corner 
inserts  may  be  made  of  non-warping  ply- 
wood or  pressed  fiber-board.  The  inserts 
are  faced  with  the  same  type  of  cloth 
used  for  the  rest  of  the  masking.  In 
theatres  where  dyed  cotton  or  other  thin 
material  is  used,  a  complete  replacement 
of  the  masking  is  in  order.  Only  black 
velour  or  an  equally  "dead"  material  is 
suitable  for  screen  masking.  The  slight 
overlap  of  the  projection  on  the  mask- 
ing should  be  invisible  to  the  audience. 

Some  projectionists  consider  screen 
masking  undesirable.  The  objection  to 
masking  is  aimed  primarily  at  the  sharp 
cutoff  produced  by  the  inch  or  two  over- 
lap of  the  picture  on  the  masking  mate- 
rial. The  unpleasing  character  of  pro- 
jected aperture  edges  prevents  the  writer 
subscribing  to  the  views  of  that  group. 

Long-focus  lenses  project  a  sharp 
image  of  the  aperture  on  the  screen 
when  the  film  is  in  focus;  while  short- 
focus  lenses  give  a  rather  fuzzy  aperture 
image.  A  small  projection  angle  results 
in  a  properly  proportioned  aperture 
image;  but  a  steep  angle  introduces  key- 
stone distortion. 

Standardization  of  the  character  of  the 
"framing"  would  be  impossible  if  mask- 
ing were  entirely  discarded.  Moreover, 
the  accidental  lodgment  of  dust  particles 
upon  the  aperture  edges  would  cause  the 
outline  of  the  picture  image  to  become 
ragged,  and  thus  attract  the  eye.  "Whis- 
kers," no  matter  how  small,  are  annoying. 
Then,  too,  machine  movements  affecting 
the  image  as  a  whole  would  be  more  con- 
spicuous, and  changeovers  would  force 
themselves  upon  the  attention  of  the  audi- 


28 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


ence   by   a   minute,   but   readily   visible, 
alteration  in  the  image  outline. 

Vignetting  Proposal  Disapproved 

Another  group  advocates  a  vignetting 
type  of  screen  masking.  The  effect 
sought  is  a  fadeaway  of  light  at  the  edges 
of  the  picture  to  give  a  blurred  boundary. 
The  selling  talk  for  this  type  of  masking 
is,  in  general,  much  better  than  the  ac- 
tual masking.  The  results,  be  assured, 
are  disappointing  because  of  the  serious 
encroachment  upon  large  areas  of  the 
screen  and  a  disconcerting  impression 
that  panoraming  and  dollying  shots  are 
being  viewed  from  the  opening  of  a 
tunnel. 

Vignetting  of  the  screen  is  an  ill-ad- 
vised attempt  to  take  the  bull  by  the 
horns  and  physically  impose  on  the 
screen  image  that  which  is  introduced 
psychologically,  and  much  more  effec- 
tively, by  sharp  cutoff,  round-cornered 
masking.  When  vignetting  effects  are  re- 
quired to  increase  dramatic  effectiveness, 
the  cinematographer  will  mask  his  cam- 
era lens  to  produce  such  an  effect. 

Some  scenes  are  enhanced  when 
blurred  by  a  romantic  haze,  but  no  sane 
projectionist  would  consider  placing 
focus-softening  filters  over  the  projector 
lenses!  The  same  line  of  reasoning  ap- 
plies to  vignetted  screens.  A  sensitive 
showmanship  arising  from  inborn  intui- 
tion prefers  suggestive  rather  than  brute- 
force  measures. 

Many  scenes — most  scenes,  in  fact — 
are  better  without  vignetting.  A  sharp 
picture  cutoff  psychologically  raises  pic- 
ture illumination  at  the  edges  of  the 
screen,  thus  counteracting  to  some  extent 
defects  in  the  projector  optical  system 
which  give  rise  to  undesirable  vignetting. 
Admitting  that  the  desirability  of  avoid- 
ing vignetting  seems  to  contradict  the 
principal  purpose  of  rounded  screen  cor- 
ners, the  psychological  veiling  of  the  defi- 
niteness  of  the  picture  boundaries  by 
such  masking  allows  us  to  adopt  per- 
fectly uniform  screen  illumination  with 
impunity. 

Allied  Problems  Important 

Those  who  consider  screen  corners  un- 
important must,  if  they  are  logical,  con- 
tinue on  to  the  premise  that  the  whole 
matter  of  masking  is  of  no  consequence. 
The  writer  has  proved  to  his  own  satis- 
faction the  tremendous  importance  of 
screen  corners  faction  by  extensive  ex- 
perimentation under  a  variety  of  theatre 
conditions.  The  first  of  these  experi- 
ments was  reported  in  IP.2  Skeptics  are 
urged  to  carry  out  such  tests  and  to  re- 
port their  findings  for  the  benefit  of  the 
craft. 

A  discussion  of  screen  masking  from 

3  "Experiment  in  Screen  Masking"  in  IP  for  Decem- 
ber.  1947,  p.  25. 


the  psychological  point  of  view  suggests 
a  number  of  allied  topics.  Brief  mention 
will  be  made  of  those  holding  special 
interest  for  projectionists. 

The  interception  of  projector  light 
beams  by  valances  or  tormentors  which 
hang  a  trifle  too  low  is  a  common  source 
of  annoyance.  The  flickering  spot  or 
strip  of  light  on  the  hanging  seems  to  be 
more  distracting  to  patrons  than  the 
shadow  cast  upon  the  top  edge  of  the 
screen.  More  often  than  not,  this  fault 
is  invisible  from  the  projection  room, 
hence  the  projectionist  should  observe 
the   valances   from   the   orchestra   while 


flashes  of  blank  light  are  projected. 

Elaborate  chandeliers  and  proscenium 
decorations  should  also  be  revamped  if 
they  dip  into  the  beams  from  any  of  the 
projectors.  Judging  from  the  presence  of 
such  defects  in  many  "de  luxe"  houses, 
the  appreciation  of  projection  matters  by 
theatre  designers  apparently  has  scarcely 
attained  the  kindergarten  stage. 

Brightly  illuminated  clocks,  exit  signs, 
sidelights,  etc.,  at  the  front  of  the  audi- 
torium also  militate  against  patron  satis- 
faction. Never  forget  that  the  patron 
demands  emotional  experiences  from  the 
screen,   and  that  in  order  to  gain  them 


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CLAYTON  BALLBEARING 

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INTERNATIONAL  PROJECTIONIST 


May  1949 


29 


he  must  really  "lose  himself"  in  the 
picture! 

Clocks  are  never  placed  in  the  vicinity 
of  the  screen  in  well-appointed  theatres: 
an  acute  consciousness  of  time  is  not 
conducive  to  the  enjoyment  of  motion 
pictures.  Exit  signs  should  have  a  mini- 
mum of  illumination — just  enough  to 
satisfy  the  law.  Bright  sidelights  near 
the  front  of  the  auditorium  should  be 
extinguished  along  with  the  house  lights 
when  the  show  starts. 

If  the  management  refuses  to  permit 
the  removal  of  an  illuminated  clock  from 
the  front  wall  of  the  auditorium,  a  15-  or 
25-watt  green  bulb  may  be  tried  in  the 
lighting  socket.  Green  is  far  less  dis- 
tracting than  red,  white,  yellow,  or  any 
other  color. 

Unfortunately,  most  municipal  and 
state  ordinances  insist  upon  red  exit 
signs.  Now,  red  is  associated  with  fire, 
blood,  and  danger;  and  because  it  is 
psychologically  a  powerful  excitant,  its 
use  in  the  vicinity  of  the  stage  should 
be  avoided.  (This  does  not,  of  course, 
preclude  the  use  of  red  decorative  light- 
ing on  the  stage  during  intermissions.) 

Great  improvements  in  projection 
lighting  have  led  to  the  use  of  higher 
levels  of  general  illumination  in  theatres 
during  the  presentation  of  pictures.  Some 
general  illumination  is  a  requirement  of 
law,  and  is  desirable  to  assist  patrons 
finding  their  way  to  and  from  seats.  But 
excessive  general  illumination  draws  at- 
tention to  the  surroundings.  The  dark- 
ness, restful  in  itself,  is  not  the  least  of 
the  attractions  of  the  theatre,  as  it  in- 


tensifies the  dramatic  effectiveness  of  the 
screen. 

Motion  picture  psychology — the  psy- 
chology of  projection,  in  particular — is 
largely  an  unexplored  universe  of  infinite 
possibilities.  There  is  no  medium  of 
expression  which  has  the  vast  scope  of 
the  screen,  or  which  can  even  approach 
it  in  sheer  emotional  power.  Nothing 
must  be  left  undone,  therefore,  to  en- 
hance this  basic  appeal. 

MAN  IN  TROPICAL  'BOX# 

{Continued  from  page  12) 
paid  usually  in  late  January,  just  before 
the  Chinese  New  Year. 

The  smaller  houses  usually  have  late 
afternoon  and  evening  shows  only,  and 
the  equipment  and  staff  are  naturally  re- 
duced accordingly.  Two  projectors  and 
a  staff  of  two  projectionists  and  a  re- 
winder  is  the  normal  arrangement. 

Ambitious  plans  have  been  tabled  for 
bigger  and  still  more  efficient  cinemas  to 
operate  under  the  Shaw  banner,  cinemas 
that  will  rank  high  and  compare  favor- 
ably with  the  best  in  the  world,  cinemas 
where  projectionists  will  be  proud  and 
happy  to  work.  The  plans  cover  many 
countries,  but  wherever  the  theatres  may 
be  located,  the  projectionists  can  rest 
assured  that  even  if  the  audiences  take 
their  highly  skilled  labors  for  granted, 
their  employers  have  schemes  which  will 
ensure  that  the  task  is  made  as  congenial 
as  possible.  The  machines  used  will  be 
the  best  that  money  can  buy,  and  environ- 
ment will  be  as  near  ideal  as  it  can  be 
made;  above  all,  they  will  be  contented 
in  their  job,  for  their  personal  welfare 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you  ?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

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Foreign   and  Canada:    Add  50c  per  year. 


Enter  my  subscription  for 


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State 


N.  W.  HUSTON— Owner,  Liberty 
Theatre  in  Columbus  and  Maywood 
Theatre  in  Galena,  Kans. — says: 

"The  regular  RCA  Service 

we  have  maintained  since  we 

installed  RCA  sound  eighteen 

years  ago  has  been  of  vital 

importance  in  our  business." 

To  get  the  benefits  of  RCA  Service 

—write:  RCA  SERVICE  COMPANY, 

INC.,  Radio  Corporation  of  America, 

Camden,  N.  J. 


will  never  be  overlooked  nor  taken  for 
granted. 

Addendum 

Evidence  that  Mr.  Shaw  is  not  merely  an 
owner  talking  for  publication  but  is  sin- 
cerely interested  in  the  welfare  of  his  work- 
ers is  contained  in  the  following  excerpt 
from  "Projection  in  the  Far  East,"  by  H. 
Campbell  Bromley,  which  appeared  in  IP 
for  June,   1948: 

Also,  the  continuous  or  "repeater"  pro- 
gram is  quite  unknown  here.  A  regulation 
provides  that  theatres  must  be  closed  to  the 
public  for  20  minutes  between  performances 
for  cleaning  and  ventilating.  Apart  from 
maintaining  a  high  standard  of  hygiene, 
which  is  most  important  in  a  tropical  coun- 
try, this  scheme  also  enables  the  patron  to 
reserve  his  seat  in  advance  and  thus  view  the 
program   undisturbed. 

Strict  Operating  Regulations 

The  theatres  operate  under  strict  regula- 
tions, very  similar  to  those  applying  in  Great 
Britain,  which  lay  down  very  definite  rules 
for  the  projectionist's  health  and  safety. 
Adequate  working  space,  efficient  ventila- 
tion and  direct  access  to  the  fresh  air,  a 
separate  rewind  room  (also  with  access  to 
the  open  air) ,  a  special  room  set  aside  for 
switchgear,  and  a  comprehensive  kit  of  fire- 
fighting  apparatus  are  some  of  the  things 
required  before  a  license  to  open  the  theatre 
is  granted. 

In  addition,  the  projectionist  must  not 
leave  a  projector  while  it  is  running,  so  there 
must  always  be  at  least  two  men  on  duty. 
From  this  it  will  be  seen  that  the  one-man 
crew  is  quite  unknown  here.  The  average 
crew  consists  of  two  qualified  men  and  a 
trainee,  but  some  of  the  larger  theatres, 
which  run  four  or  five  shows  a  day,  will  have 
up  to  five  projectionists. 


30 


INTERNATIONAL  PROJECTIONIST     •     May  1949 


SO  MUCH 


ior  so  LITTLE 


$0.00 


3 


per  copy 
postage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


S&nd 


(Do  Thai  (bslmf 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18,  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a  copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
Name  


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&\ 


S.  PAT.  OFF. 


NOW 

and 

ALWAYS 


It  will  be  the  best  projector — 
soundly  engineered — quality  built. 
It  will  wear  well  and  last  long. 

It  will  be  distinctive  in  design — 
because  Simplex  was  first  to  be  so 
designed.  It  will  have  personality. 


It  will  perform  efficiently — run 
smoothly  —  project  the  best 
pictures. 

It  will  be  economical  —  giving 
you  more  years  of  operation. 

It  will  be  built  to  include  the 


basic  features  which  always  have 
been  part  of  Simplex  and  for 
which  Simplex  is  preferred  the 
world  over — 

Appearance   •   Performance 
Economy 


MANUFACTURED    BY    INTERNATIONAL    PROJECTOR    CORPORATION    •   BLOOMFIELD,    NEW   JERSEY 


IB 


JUNE 


1949 


VOLUME  24 


NUMBER  6 


30c  A   COPY    •    $2.50  A  YEAR 


^   #s»  J  > 


He  started  retiring  today! 


. . .  and  it  feels  good! 

It's  going  to  take  time,  but  the  point  is 
.  .  .  he's  taken  that  all-important  first  step 
.  .  .  he's  found  a  way  to  make  saving  a  sure, 
automatic  proposition  .  .  . 

He's  buying  Savings  Bonds,  the  safest  in- 
vestment there  is,  through  the  Payroll  Savings 
Plan! 

This  makes  saving  an  absolute  certainty! 
You  don't  handle  the  money  to  be  invested 
.  .  .  there's  no  chance  for  it  to  slip  through 
your  fingers  and  .  .  .  U.  S.  Savings  Bonds 


pay  you  4  dollars  for  every  3  invested,  in 
ten  years! 

Think  it  over!  We  believe  you'll  agree  that 
bonds  are  the  smartest,  surest  way  there  is 
to  save. 

Then — sign  up  for  the  Payroll  Savings 
Plan  yourself,  today!  Regardless  of  your 
age,  there's  no  better  time  to  start  retiring 
than  right  now! 

P.  S.  If  you  are  not  eligible  for  the  Payroll 
Savings  Plan,  sign  up  for  the  Bond-A-Month 
Plan  at  your  bank. 


Automatic  saving  is  sure  saving— U.  S.  Savings  Bonds 

Contributed  by  this  magazine  in  co-operation  with  the  Magazine  Publishers  of  America  as  a  public  service. 


©C1B    198474 

UM2719-;9 


INTERNATIONAL 

R0JECTI0NIS1 

With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


JUNE!  1949 


/ 
Number  6 


Index  and  Monthly  Chat   3 

Distortion     Factors     in     Sound 

Reproduction      5 

Robert  A.  Mitchell 

Nylon  Gears  on  the  RCA  '400' 
16-mm    Unit    8 

Addenda:     'Matched'    Projector 

Optics    11 

R.  H.  Cricks 
Robert  A.  Mitchell 

'Stilb'   and   Other   Irritants   Re- 
duced to  Americanese 12 

The  Effect  of  Carbon  Cooling  on 

High-Current  Arcs 14 

Wolfgang  Finkelnburg 


Letters  to  the  Editor 17 

In  the  Spotlight 18 

Polarity  Is  Strictly  Relative   .  .        20 
A.  Buckley 

Book  Review    22 

Harry     Shiftman,     Student     of 
Labor  Relations 23 

IA  Election    27 

News  Notes 

Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL   PROJECTIONIST   PUBLISHING   CO.,   INC. 

19   West   44  Street,  New    York    18,  N.   Y. 

R.    A.    ENTRACHT,    Publisher 

SUBSCRIPTION   REPRESENTATIVES 

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act  of  March  3,  1879.  Entire  contents  copyrighted  1949  by  International  Projectionist 
Publishing  Co.,  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


MONTHLY   CHAT 

Not  So  Random  Thoughts:  When 
Tv  penetrates  into  towns  such  as 
Syracuse,  N.  Y.  (with  other  locales  of 
150,000  population  that  lie  on  the  coaxial 
cable  line  due  to  debut  within  the  next 
few  months)  the  conclusion  that  there 
must  be  "something"  there  for  the  Tv 
boys  is  inescapable.  Without  regard  to 
the  quality  of  Tv  images  at  present,  one's 
thoughts  inevitably  hark  back  to  the  era 
when  radio  and  dog  tracks  and  Bingo 
were  regarded  as  the  prime  opposition 
to  the  theatre  box-office  for  the  almighty 
dollar  which  keeps  you,  and  you.  and  us 
and  a  lot  of  other  people  in  the  exhibi- 
tion field  going  along. 

Nobody  knows  at  the  moment  just  how 
the  theatre  box-office  will  fare  when  100 
more  Tv  outlets  are  spotted  in  Syracuse, 
in  Hartford,  in  Indianapolis,  in  Colum- 
bus, in  Portland  and  in  like  towns.  But 
that  such  Tv  outlets  are  definitely  oppo- 
sition to  the  theatre  box-office  may  not  be 
reasonably  denied. 

We  commend  to  our  readers,  and  par- 
ticularly to  those  forward-looking  indi- 
viduals who  can  see  beyond  their  noses, 
the  lead  item  of  "In  the  Spotlight"  on 
page  18  of  this  issue.  Tv  activity  is  cer- 
tainly not  going  to  sponge-up  all  the 
losses  certain  to  be  incurred  by  the  thea- 
tre field  as  a  result  of  the  incursions  of 
Tv  within  the  next  year,  but  it  cannot 
fail  to  provide  a  cushion  for  the  terrific 
impact  which  IP  thinks  Tv  will  exert 
against  the  motion  picture  theatre  as 
presently  constituted.  Half  a  loaf  .  .  . 

ARTICLES  appearing  in  recent  is- 
sues of  IP  have  lately  been  the 
focal  point  of  interest  for  motion  picture 
technicians  the  world  over — with  par- 
ticular emphasis  upon  those  cinemati- 
cians  in  the  British  Isles,  who  not  only 
are  convinced  that  post-war  British  pro- 
jectors are  the  "last  word"  in  design  and 
performance  but  also  refuse  to  accept  the 
IP  conception  of  the  ideal  projection 
optical  setup. 

For  all  too  long  now  projectionists 
have  extended  varying  degrees  of  accept- 
ance to  those  equipment  units  -^hich, 
issued  by  a  reputable  manufacturer, 
were  purchased  upon  the  basis  of  repre- 
sentation rather  than  performance  day-in 
and  day-out.  The  time  has  long  since 
passed  when  projectionists  need  accept 
any  equipment  other  than  on  the  basis  of 
detailed  data,  supported  by  impartial 
performance  records,  of  not  only  what 
but  how;  in  other  words,  how  does  a 
given  unit  get  that  way. 

IP  has  ever  sought  to  be  provocative 
in  terms  of  providing  food  for  thought, 
as  opposed  to  the  mere  ladling-out  of 
data  which  is  more  or  less  the  sugar- 
coating  on  fundamentals.  The  hackles 
rising  on  the  neck  of  our  British  and 
other  contemporaries  merely  serves  to 
prove  that  IP  still  is  in  there  serving  up 
those  data  which  best  serve  to  advance 
the  interests  of  the  art  and  the  craft. 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


/  ^  MAGNA 


M. 


£W 


MAGNARC 


TRADE    MARK    REG 


1-KW  TO  70  AMPS 


"HY-AX"  ARC  MAGNET 

HY-LUMEN"    REFLECTOR 


More  light  at  40  to  70  amperes  than  ever  thought  possible.  .  .  . 
Equals  and  excels  any  reflector  lamp  to  85  amperes.  .  .  .  Highest 
ratio  of  screen  lumens  per  watt  consumed  at  the  arc.  ...  At  70 
amperes,  with  a  projector  having  an  efficient  DISC  type  revolv- 
ing shutter,  it  develops  the  maximum  light  that  can  be  used 
without  a  heat  filter.  .  .  .  Operating  costs  under  these  conditions, 
are  far  below  that  of  85-ampere  lamps. 

Magnarc  Lamps  assure  80%  side-to-center  (SMPE  Standard) 
screen  light  distribution.  .  .  .  They  are  the  first  choice  and  pre- 
ferred lamp  of  large  or  small  Drive-Ins  and  Theatres. 


"FIRST    WITH    THE    FINEST' 


120-180  AMPERES 


TRADE  MARK   REG 


NEW    MAGNETIC    STABILIZER 

~\  This  modern  lamp  produces  all  the  light  there  is.  .  .  . 
It  is  the  standard  equipment  of  the  nation's  largest  and 
finest  theatres.  .  .  .  Used  by  90%  of  the  largest  Drive-In 
Theatres.  .  .  . 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  light  volume,  when 
used  with  projectors  that  have  efficient  DISC  type 
revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions. 


1  1 


WHY    EXPERIMENT? 


i  i 


J.E.McAULEY  MFG. CD. 


552 


554    WEST    ADAMS    STREET 

CHICAGO  6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


INTERNATIONAL    PROJECTIONS 


jmrnlmmmm^  Wim* 


VOLUME  XXIV 


JUNE   1949 


NUMBER  6 


Distortion  Factors  in  Sound  Reproduction 


FAR  more  anxiety  is  occasioned  in  pro- 
jection rooms  by  sound  distortion  than 
by  complete  outages  of  sound.  As 
sound  troubles  go,  a  total  loss  of  sound 
is  comparatively  definitive:  a  cursory  in- 
spection of  the  system  usually  reveals  the 
cause  at  once.  Moreover,  the  better  am- 
plifiers are  provided  with  emergency  cir- 
cuits which  enable  the  projectionist  to 
trace  the  trouble  at  his  convenience. 

Not  so  with  "bad  sound."  The  ampli- 
fier still  works — nothing  has  failed  com- 
pletely— yet  the  system  is  definitely  not 
functioning  as  it  should.  Particularly 
exasperating  are  those  cases  of  distortion 
so  slight  that  they  are  noticed  only  in  the 
relative  quiet  of  the  theatre. 

The  difference  between  good  and  poor 
sound  quality  is  often  obscure  and  in- 
capable of  exact  description.  We  notice 
such  effects  as  "fluttery"  sound,  "hollow," 
"tubby,"  "harsh,"  and  "noisy"  sound  and 
speak  of  all  of  them  as  "distorted."  Ob- 
viously, a  whole  world  of  phenomena  is 
included  under  this  heading. 

Sound  and  Hearing 

Sound  may  exist  without  anyone  hear- 
ing it.  There  are  sounds  too  low-pitched 
to  hear,  and  sounds  too  high-pitched  to 
hear.  A  "silent"  dog  whistle  is  a  case  in 
point.  The  human  ear  hears  nothing 
when  such  a  whistle  is  blown,  but  the 
canine  ear,  being  sensitive  to  certain 
sounds  we  describe  as  "supersonic,"  re- 
sponds to  the  whistle. 

Sound,  we  know,  is  nothing  but  a  suc- 
cession of  pressure  waves  in  a  medium  of 
some  kind — usually  air.  The  velocity  of 
sound  in  air  is  approximately  1,100  feet 


By  ROBERT  A.  MITCHELL 


per  second.  The  greater  the  pressure- 
amplitude  of  the  waves,  the  louder  the 
sound.  Volume,  therefore,  is  a  function 
of  the  energy  of  the  waves.  The  volume 
of  sounds  is  most  conveniently  measured 
in  decibels,  or  sensation-units,  a  logarith- 
mic system  familiar  to  all  projectionists. 

The  distinction  between  tones  and 
noises  is  very  important.  When  sound 
waves  beat  against  our  eardrums  irregu- 
larly we  hear  a  noise;  but  when  the 
dominant  wave-pattern  in  a  train  of  waves 
recurs  at  regular  intervals,  we  hear  a 
tone.  Periodicity,  then,  is  the  difference 
between  tones  and  most  noises. 

Tones  (and  quasi-tonal  noises)  possess 
the  property  of  "pitch,"  a  direct  result  of 
the  frequency  at  which  the  wave-patterns 
repeat.  High-pitched  tones  result  from 
rapid  vibrations  (high-frequency  waves)  ; 
low-pitched  tones  result  from  slow  vibra- 
tions (low-frequency  waves).  Because 
the  velocity  of  sound  in  any  specified 
medium  is  independent  of  frequency, 
high-frequency  sounds  have  shorter  wave- 
lengths   than    low-frequency    ones. 

The  frequency  of  tones  is  measured  in 
complete  cycles  per  second  (c.p.s.),  and 
it  is  customary  to  speak  of  a  complete 
cycle  of  sound  as  a  "double  vibration." 
The  conventional  abbreviation  D.v.  means 
"double    vibrations    per    second." 

Sounds  lower  than  20  d.v.  are  called 
subsonic  because  they  fall  below  the 
range  of  the  human  ear.  The  upper  limit 
of    hearing    varies    considerably    among 


different  individuals.  As  an  average,  how- 
ever, we  set  20,000  d.v.  as  the  highest 
pitched  sound  that  can  be  heard:  sounds 
of  greater  frequency  than  this  fall  within 
the  supersonic  range.  (Most  young  chil- 
dren are  able  to  hear  30,000  d.v.  easily; 
very  few  elderly  people  can  hear  above 
10.000  d.v.) 

The  average  listener,  therefore,  can 
hear  only  those  sounds  between  20  and 
20,000  d.v.  (easy  figures  to  remember), 
but  strong  subsonic  sounds  may  be  felt 
as  a  rumble,  while  intense  supersonic 
sounds  produce  nervous  irritation  and  a 
sensation   of  warmth  in  the  ears. 

Frequency  Range  Data 

The  standard  of  musical  pitch  is  the 
note  designated  as  "middle  C."  This  note 
is  ordinarily  assigned  a  frequency  of  256 
D.v.,  though  "international  concert  pitch" 
is  a  trifle  higher.  Now,  any  two  notes 
whose  frequencies  are  in  the  ratio  1 :2  or 
2:1  are  said  to  be  separated  by  an  octave. 
The  standard  piano  keyboard  has  a  range 
of  Sy^  octaves.  The  C  an  octive  above 
middle  C  accordingly  vibrates  512  times 
per  second,  and  the  C  an  octive  below 
middle  C  128  times  per  second.  The 
highest  note  on  a  piano  (four  C's  above 
middle  C)   has  a  frequency  of  4,096  d.v. 

It  has  been  known  for  many  centuries 
that  some  combinations  of  tones  are  much 
more  harmonious  than  others.  Any  three 
notes  whose  frequencies  stand  in  the 
simple  ratio  4:5:6  form  what  musicians 
call  a  "major  chord."  If  we  play  do,  mi, 
so  on  a  piano  or  organ,  using  middle  C 
for  any  higher  C)  for  do,  we  can  readily 
appreciate  the  warm,  harmonious  nature 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


of  the  C-Major  triad.  On  the  other 
hand,  if  we  play  do,  mi,  so,  using  for  do 
any  of  the  three  C's  below  middle  C,  we 
shall  hear  a  rather  confused  jumble  of 
sound  instead  of  a  pleasing  chord. 

The  chord  is  the  same  because  the 
vibration  ratios  are  still  4:5:6,  so  we  won- 
der why  distortion  should  appear  in  the 
bass.  It  would  appear  that  the  human 
ear  is  unable  to  judge  the  exact  pitch  of 
very  low  notes.  All  musical  compositions 
from  the  most  complex  symphonies  and 
"tone  poems"  to  the  most  elementary 
popular  ballads  have  considerably  fewer 
sustained  chords  in  the  bass  than  in  the 
treble.  Simple  "doubling  in  octaves"  is 
the  most  common  way  of  enriching  the 
low  bass. 

Theatre  Systems  Weak  on  L-F 

The  best  theatre  sound  systems  have 
a  reasonably  uniform,  or  "flat,"  fre- 
quency-response range  of  from  100  to 
4,000  D.v.,  and  they  also  reproduce  with 
more  or  less  fidelity  the  frequencies  from 
40  to  100  d.v.  and  from  4,000  to  9,000 
d.v.  The  maximum  range  of  soundfilm 
reproduction  is  accordingly  40  to  9,000 
d.v.  When  we  stop  to  consider  that  the 
highest  note  that  the  average  person  can 
detect  is  only  about  an  octave  above 
9,000  D.v.,  and  that  the  lowest  audible 
sound  is  only  an  octave  below  40  d.v., 
we  should  have  few  complaints  regarding 
the  over-all  frequency  range  of  modern 
sound  systems.  There  is  room  for  im- 
provement only  on  the  low-frequency  end. 
The  lowest  musical  note  of  definite 
pitch  is  found  in  the  diapason  "stop"  of 
the  largest  pipe  organs.  It  has  a  fre- 
quency of  only  16  d.v.,  and  since  this  is 
below  the  limit  of  distinct  audibility,  it 
is  felt  as  a  rumble  coming  through  the 
floor  of  the  building,  rather  than  heard. 
No  theatre  sound  system  can  reproduce 
this  tone,  for  to  do  so  (assuming  that  it 
could  be  recorded)  would  require  giant 
speakers  of  such  power  as  to  cause  the 
floor  and  walls  of  the  theatre  to  vibrate 
strongly  and  thus  impart  a  pulsating 
sensation  to  the  audience. 

Thunder  and  earthquake  noises  also 
contain  definite  tones  of  subsonic  fre- 
quencies, and  the  failure  of  theatre 
sound  systems  to  recreate  these  sounds 
realistically  is  familiar  to  all  who  have 
ever  heard  thunderstorms  or  earth- 
quakes. Thus  the  need  for  improvement 
on  the  low-frequency  end  of  sound  re- 
production. 

The  highest  note  on  the  standard  piano 
keyboard,  as  before  stated,  is  4,096  D.v. 
Some  pipe  organs  go  as  high  as  8,192 
d.v.  in  the  stop  called  flute  celestes  (but 
no  actual  flute  can  play  a  note  higher 
than  2,304  d.v.).  "Juke  boxes"  are 
often  arranged  to  cut  off  all  frequencies 
above  4,000  d.v.  to  eliminate  upleasant 
needle  scratch,  but  phonographs  de- 
signed for  high-fidelity  reproduction   of 


B 
C 


FIG.  1.  Variable-density  (B)  and  variable-area 
(C)  soundtrack  records  corresponding  to  the  sine- 
wave  oscilloscopic  graph  of  a  "pure"  tone  (A). 

the  finest  orchestral  music  in  the  home 
are  capable  of  giving  good  response  up 
to  10,000  D.v.  (The  writer  holds  that  a 
cutoff  at  about  8,000  D.v.  does  not  injure 
musical  reproduction,  and  that  a  smart 
record  company  will  one  day  produce  a 
superlong-playing  record  revolving  at  20 
r.p.m.)  Radio  programs  relayed  via 
network  hookups  cut  off  a  little  above 
6,000  d.v. 

Frequency  Distortion 

The  first  theatre  sound  systems  were 
considered  excellent  if  they  reproduced 
(after  a  fashion)  the  frequencies  from 
100  to  5,000  D.v.  Contrast  this  with  the 
modern  frequency  range!  Moreover,  a 
high  percentage  of  distortion  was  present 
in  the  output  of  the  older  systems — 
soundheads,  amplifiers,  and  speakers  all 
contributing. 

One  particularly  annoying  type  of 
distortion  was  the  over-amplification  of 
certain  frequencies  and  the  attenuation 
of  others.  This  is  called  frequency  dis- 
tortion, which  means  that  the  response 
curve  is  not  flat  but  rises  and  falls  in 
an  irregular  way  as  we  pass  from  the 
lowest  frequencies  to  the  highest. 

Poorly  designed  speaker  units  can  ruin 
sound  quality  by  introducing  frequency 
distortion.  No  "off-make"  speaker  should 
ever  be  purchased  for  use  in  a  motion 
picture  theatre  until  the  projectionist  has 
examined  and  approved  the  response 
data  obtained  by  energizing  the  speaker 
with  a  level  input  signal  covering  the 
entire  frequency  spectrum  from  30  to 
10,000  d.v.  Low-  and  high-frequency 
units  should  provide  satisfactory  re- 
sponse characteristics  over  that  part  of 
the  frequency  spectrum  which  each  is 
intended  to  cover,  and  generous  allow- 
ance made  for  overlap  of  the  frequency 
bands. 

Frequency  distortion  may  also  arise 
from  magnetically  saturated  or  other- 
wise defective  transformer  cores.  Amp- 
lifiers employing  transformer-coupling 
throughout  are  always  suspect.  The 
remedy?  Replace  obsolete  equipments 
with  units  of  modern  design.  It  is  truly 
astonishing  how  many  old-fashioned 
sound  systems  still  are  in  use.  Indeed, 
hardly  a  day  passes  when  a  sound  service 
man  somewhere  in  the  U.S.A.  does  not 


write  "quality  limited  by  equipment"  in 
a  service  report. 

A  rough  estimate  of  frequency  distor- 
tion may  be  made  by  simply  listening 
to  the  loudness  of  the  various  frequen- 
cies via  a  multi-frequency  test  reel.  (A 
more  accurate  method  will  be  discussed 
shortly.)  With  ordinary  recordings  fre- 
quency distortion  is  evidenced  by  the 
occasional  occurrence  of  unduly  sharp 
or  boomy  sounds,  and,  when  due  to 
speaker  resonance,  by  a  peculiar  timbre 
of  the  sound  quality  ("tubby,"  "wooden," 
"metallic,"  or  "hollow"). 

Tone  Color,  or  Timbre 

Tone  quality  or  timbre,"  together  with 
volume  and  pitch,  is  one  of  the  impor- 
tant characteristics  of  sounds.  Timbre 
enables  us  to  recognize  voices  and  to 
distinguish  different  musical  instruments 
by  listening.  Thus  the  sound  of  a  flute 
may  be  told  from  that  of  a  cornet  even 
when  playing  the  same  note.  The  tonal 
brilliance  and  range  of  an  orchestral 
pipe  organ  is  due  to  the  characteristic 
qualities  of  the  various  stops. 

What  factor  in  sound  waves  is  respon- 
sible for  tone  quality?  The  simplest 
sound  wave  consists  of  pressure  varia- 
tions which,  when  plotted  graphically 
(or  when  their  electrical  equivalents  are 
supplied  to  an  oscilloscope),  describe  a 
sine  wave — the  record  of  a  pure  tone. 

A  pure  tone,  even  though  the  simplest 
possible,  is  a  really  extraordinary  sound. 
It  is  quite  characterless.  Now,  nothing 
in  nature  ever  produces  a  pure  tone,  so 
it  is  only  by  striking  a  carefully  con- 
structed tuning  fork  with  a  felt-covered 
hammer,  or  by  feeding  sinusoidal  current 
into  a  loudspeaker,  that  we  can  obtain 
a  pure  tone  free  from  the  elements  which 
cause  timbre. 

How  does  a  pure  tone  sound?  It  may 
be  imperfectly  described  as  a  "hollow 
hum."  Strike  a  large  bell  with  the  fist. 
When  the  sharper  tones  have  all  nearly 
faded  away,  bring  the  ear  close  to  the 
bell.  The  "hum  tone"  of  the  bell,  a 
pure  tone,  will  then  be  heard. 

Part  A  of  Fig.  1  represents  an  oscillo- 
scopic record  of  a  pure  tone — a  sine 
wave.  B  illustrates  a  variable-density 
soundtrack  record  of  the  pure  tone  in 
A,  while  C  shows  a  corresponding  vari- 
able-area soundtrack.  Soundtracks  of 
pure  tones  of  various  frequencies  are 
encountered  in  test  films. 

Tones  Above  the  Fundamental 

All  musical  tones  and  sounds  of  defi- 
nite pitch  consist  of  periodic  vibrations. 
Every  such  tone  has  an  underlying  pure 
tone,  the  frequency  of  which  establishes 
the  pitch ;  but  the  pure  fundamental  tone 
is  seldom  heard  as  such  in  voices  and 
musical  instruments.  Instead,  our  ears 
hear  a  modified  tone,  the  resultant  of  a 
number  of  combined  pure  tones,  those 
higher   than   the  fundamental  providing 


INTERNATIONAL  PROJECTIONIST 


June  1949 


the  characteristic  tone  quality  of  the 
sound. 

The  tones  above  the  fundamental  in 
any  sound  are  called  partials,  or  over- 
tones. Most  overtones  have  frequencies 
which  are  2,  3,  4,  5,  6,  7,  etc.,  times  the 
frequency  of  the  fundamental  (that  is 
to  say,  they  are  2,  3,  4,  etc.,  full  octaves 
above  the  fundamental),  and  when  this 
is  the  case  they  are  called  harmonics. 
An  overtone  having  twice  the  frequency 
of  the  fundamental  is  called  the  "second 
harmonic";  one  having  three  times  the 
fundamental  frequency,  the  "third  har- 
monic," etc.,  the  fundamental,  itself, 
being  thought  of  as  the  "first  harmonic." 
Nevertheless,  not  all  overtones  bear  a 
harmonic  relationship  to  the  fundamen- 
tal. 

Figure  2  shows  the  graphs  of  two  pure 
tones  of  equal  amplitude,  but  one  of  the 
tones  has  exactly  tivice  the  frequency  of 
the  other.  When  these  are  combined  to 
form  a  compound  tone  having  a  definite 
quality,  the  tone  of  lower  frequency  is 
the  fundamental,  and  that  of  higher  fre- 
quency is  the  overtone.  These  two  tones 
are  shown  combined  in  four  different 
ways,  depending  on  the  phase  relation- 
ship between  the  fundamental  and  the 
harmonic  overtone;  but  even  though  the 
records  of  the  four  resultant  compound 
tones  look  different,  they  sound  the  same. 
Phase  difference,  therefore,  does  not 
affect  quality;  a  fortunate  fact,  foras- 
much as  electrical  circuits  often  cause 
a  shift  of  phase. 

The  compound  tone  created  by  com- 
bining a  strong  "second  harmonic"  with 
the  fundamental  tone,  as  in  Fig.  2,  is 
the  rich,  mellow  voice  of  the  organ's 
viol  d'amour. 

Not  all  compound  tones  are  formed  so 

zlwo   pure  tones^^ 

FUNDAMENTAJ? 


OVERTONE   WWWV 

combine  to  give : 


PHASE 
DIFFERENCE 


o£ 


90c 


WWWV 
0  VAXVA 


180 


270°    y\/v/\/x/\/x/\ 

FIG.  2.  The  combining  of  two  "pure"  tones  to 
give  a  compound  tone  possessing  a  character- 
istic tonal  quality.  Even  though  the  four  result- 
ant tones  have  a  different  appearance,  due 
to  differences  in  phase,  they  sound  the  same 
because  the  ear  takes  no  account  of  phase 
difference.  The  tone  is  that  of  the  v;o/  d'amour 
stop   of  an   organ. 


simply.  Interference  beats,  "disturbed 
harmonics,"  etc.,  all  play  a  part  in  the 
overtone  patterns  of  many  highly  indi- 
vidualized tones.  Major-chord  overtones 
impart  a  sturdy  fullness  to  a  tone,  while 
faint  minor-chord  overtones  result  in  a 
pensive,  mysterioso  tone.  In  addition  to 
the  presence  of  overtones,  musical 
sounds  are  sometimes  further  modified 
by  the  tremolo,  a  kind  of  wavering  effect. 
Figure  3  represents  oscilloscopic  rec- 
ords of  several  characteristic  compound 
tones.  All  of  these  are  of  the  same 
pitch  (same  frequency  of  the  fundamen- 
tal), five  complete  cycles  of  sound  being 
illustrated  in  each  case.  Let  us  briefly 
analyze  these  sounds. 

Characteristic  Compound  Tones 

The  tone  of  the  violin  contains  a 
strong  second  harmonic,  a  somewhat 
weaker  third  harmonic,  and  a  number  of 
fainter  harmonics  up  to  the  twelfth.  The 
best  violins  produce  fewer  harmonics, 
and  are  hence  less  "harsh"  than  the 
cheaper  instruments.  The  tone  of  the 
flute  is  very  nearly  a  pure  tone,  but 
a  weak  second  harmonic  perceptibly 
modifies  the  sound  quality. 

The  fundamental  of  the  clarinet  is 
modified  by  numerous  moderately  strong 
overtones,  notably  the  eighth,  ninth,  and 
tenth  harmonics.  The  oboe  is  unusual 
in  that  the  fundamental  is  weaker  than 
many  of  the  overtones.  This  state  of 
affairs  also  obtains  with  the  hautboy  stop 
of  the  organ  and  with  all  other  instru- 
ments producing  reedy,  oriental  tones. 

The  sound  of  a  bell  has  a  weak  funda- 
mental modified  by  a  multiplicity  of 
dissonant,  clashing  overtones,  very  few 
of  which  are  in  harmony  with  the  funda- 
mental. When  the  sound  of  a  distant 
churchbell  meets  our  ears,  we  hear  not 
the  fundamental,  but  only  the  strongest 
of  the  overtones.  The  "pitch"  of  such  a 
bell  is  ordinarily  two  or  three  octaves 
above  the  fundamental  hum  tone.  Cym- 
bals and  Chinese  gongs  are  so  dissonant 
that  it  is  indeed  difficult  to  assign  any 
definite  pitch  to  them. 

The  four  vowel  sounds  pictured  war- 
rant special  attention.  The  fundamental 
frequencies  of  the  female  voice  range 
from  about  180  d.v.  to  300  d.v.  ;  of  the 
male  voice,  from  100  d.v.  to  200  d.v.  If 
a  sound  system  cuts  off  at  about  300  D.v., 
we  can  hear  reproductions  of  the  human 
voice  readily  enough,  but  only  as  boomy, 
rumbling  sounds.  Hardly  a  single  word 
could  be  understood.  This  is  because 
articulation  depends  upon  the  overtones, 
not  the  fundamentals.  Now  the  over- 
tones in  speech  extend  up  to  4,000  d.v.; 
the  sibilants  and  other  transient  talking 
noises  may  go  even  higher.  At  any  rate, 
it  may  safely  be  said  that  sound  systems 
must  have  a  uniform  frequency  response 
from  100  to  4,000  d.v.  in  order  to  repro- 
duce speech  in  its  natural  quality. 

The   timbre   of  voice   tones   is   varied 


Violin      V\/VA/A/A, 


Flute 


Clarinet     \J\/\/\/^ 


Oboe 


\aW\4/AaJ^Ai^Aaj 


Bell  XFXMAvVX/1^ 

Voweiosound  \aMaVWvVaAa 

Vowel    sound 
AW 

Vowel  sound 
AH 

Vowel   sound 


FIG.  3.    Oscilloscopic  records  of  several  highly 

characteristic    sounds.     Five    complete    sounds 

(double  variations)  of  the  fundamental  tone  are 

shown  for  each  of  these  sounds. 

in  enunciation  by  altering  the  shape  of 
the  oral  cavity  and  by  changing  the 
relative  strength  of  the  fundamental 
emitted  by  the  vocal  cords.  As  many 
as  20  overtones  have  been  detected  in 
the  human  voice,  and  of  these  some  are 
harmonics  and  some  are  not. 

Distinguishing  Different  Sounds 

Many  of  the  characteristic  sounds  at 
the  beginning  and  end  of  speech  and 
musical  tones  are  mere  noises  called 
transients.  The  initial  p  and  the  final  t 
in  the  word  "projectionist"  are  transi- 
ents. They  have  no  definite  pitch.  The 
striking  of  the  bars  of  a  xylophone  and 
the  plucking  of  the  strings  of  a  guitar 
are  musical  transients.  Additional  transi- 
ents are  sometimes  given  to  notes  played 
on  the  organ  by  the  device  called 
Chinese   blocks. 

It  may  be  wondered  how  two  or  more 
notes  from  different  sources  may  be  dis- 
tinguished when  they  are  sounded  to- 
gether. This  is  sometimes  difficult,  par- 
ticularly when  the  tones  of  the  different 
instruments  have  the  same  pitch;  but 
two  important  factors  assist  the  ear  to 
disentangle  two  superposed  tones: 

First,  the  overtones  from  any  one 
source  are  usually  fainter  than  the  funda- 
mental (but  not  always),  hence  any  dis- 
crepancy in  the  subconsciously  presup- 
posed overtone  intensities  is  immediately 
interpreted  as  sound  from  more  than  one 
source.  Second,  two  musical  instruments 
can  seldom  be  made  to  begin  playing 
at  exactly  the  same  moment  and  to  main- 
tain the  same  sound  intensity  relative  to 
each  other  throughout  the  period  of 
sounding  the  note. 

An  outstanding  exception  is  the  organ 
which,  after  all,  is  an  orchestra  of  many 
instruments  played  on  a  keyboard  by  one 
person.     When  two   or  more   stops   are 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


coupled,  the  tones  usually  begin  and  end 
at  the  same  instant  and  maintain  the 
same  volume  relative  to  each  other  all 
the  time  they  are  "speaking."  The  ear 
is  thus  deceived — especially  when  the 
notes  do  not  differ  in  fundamental  pitch 
by  more  than  an  octave — and  a  new 
compound  tone,  different  in  quality  from 
any  of  the  compound  tones  which  com- 
pose it,  is  heard. 

The  number,  pitch,  and  relative  inten- 
sity of  the  various  individual  pure  tones 
which  go  to  make  up  a  compound  tone 
may  be  ascertained  from  oscilloscopic 
records  or  variable-area  soundtracks  by 
Fourier's  analysis.  The  work  is  so  diffi- 
cult, however,  that  wave-analyzing  ma- 
chines which  mechanically  perform  the 
necessary  integrations  are  often  used. 
The  results  of  such  analyses  are  valuable 
to  designers  of  electric  organs,  in  which 
complex  pipe-organ  and  other  instru- 
mental tones  are  imitated  by  electrically 
generating  and  combining  all  the  neces- 
sary pure  tones  in  the  correct  degrees  of 
intensity. 

Non-Linear  Distortion 

It  can  now  be  appreciated  that  any 
sound  amplifier  which  introduces  spuri- 
ous frequencies  into  the  sound  changes 
the  quality  of  the  recorded  sound.  This 
most  serious  type  of  distortion  is  termed 
/;  on-linear  distortion  because  it  is  due 
to  a  non-linear,  or  non-proportional, 
relation  between  signal  and  response. 
It  may  arise  from  electrical,  optical,  or 
mechanical  causes. 

An  oscilloscope  is  used  for  the  scien- 
tific determination  of  non-linear  response 
in  theatre  sound  systems.  Test  films  or 
disc  records  of  pure  tones  at  different 
frequencies  are  played,  and  the  spurious 
frequencies  become  visible  as  a  distor- 
tion of  the  sine  wave  on  the  cathode-ray 
tube. 

Any  departure  from  the  sine-wave 
form  indicates  that  two  or  more  pure 
tones  are  superimposed. 

Ordinary  listening  will  detect  non- 
linear distortion  as  a  "harsh,"  "shrill," 
"raspy,"  "mushy"  or  other  irritatingly 
unnatural  quality  of  the  reproduced 
sound.  As  a  rule,  this  type  of  distortion 
is  most  pronounced  at  high  volume  levels 
and  in  sound  of  moderately  high  pitch. 
In  many  cases  it  is  caused  by  nothing 
more  serious  than  a  defective  amplifier 
tube. 

Among  other  factors  affecting  sound 
quality  are  the  directional  characteristics 
of  the  speakers  (high-frequency  speak- 
ers, especially),  the  natural  resonance 
and  reverberation  of  the  auditorium,  ex- 
traneous noises  in  the  sound  (hums, 
squeals,  thumps,  clicks,  and  hisses),  and 
a  fiuttery  movement  of  the  film  or  disc 
record. 

[To  be  Continued] 


Nylon  Gears  on  the  RCA  400'  16-mm  Unit 


EVER  since  the  introduction  in  1931  of 
the  first  16-mm  projector  to  success- 
fully employ  a  photographic  sound 
track  "(the  PG-38)  RCA  has  been  dili- 
gently seeking  to  effect  an  improvement 
in  the  projector  gear  train.  It  is  obvi- 
ous, therefore,  that  the  decision  to  use 
nylon  gears  in  its  current  Model  400 
series  of  16-mm  projectors  was  not  made 
on  the  spur  of  the  moment. 

The  matter  of  obtaining  a  uniform 
supply  of  precision  cut  gears  have  the 
necessary  close  tolerances,  tooth  forms, 
etc.,  for  this  exacting  service  has  been 
a  general  problem  over  the  years.  While 
the  drawings  for  these  gears  have  always 
been  the  same,  individual  suppliers  of 
fabricated  steel  and  laminated  phenolic 
gears  have  always  tended  toward  a  cer- 
tain amount  of  compromise.  This  pre- 
sented a  new  problem  of  gear  supply 
with  each  manufacturer  who,  of  course, 
was  greatly  influenced  by  the  type  of 
fabricating  machinery  and  tools  in  his 
plant,  his  particular  manufacturing  tech- 
niques, supply  of  labor  and  its  degree  of 
skill. 

In  order  to  strike  at  the  root  of  this 
problem,  the  idea  of  a  molded  gear  often 
presented  itself  to  the  minds  of  RCA 
engineers.  But  for  the  lack  of  a  suitable 
material,  this  idea  might  have  been 
adopted  years  ago. 

Rigorous  Tests  Passed  Easily 

With  the  availability  of  nylon  plastics 
materials,  the  molded  gear  idea  seemed 
closer  to  realization,  thus  an  experi- 
mental set  of  gears  was  cut  from  nylon 
rod  stock  and  placed  on  life  test.  When 
after  1000  hours  of  continuous  normal 
use  these  gears  came  through  with  flying 
colors,  an  accelerated  test  under  excess 
load  was  made  which  firmly  convinced 
RCA  of  the  practicability  of  nylon  for 
this  purpose. 

Typical    nylon    gear    train    as    utilized    in    the 
RCA    16-mm   '400'   series    projectors. 


On  the  accelerated  test,  the  gears  ran 
well  beyond  their  expected  life  before 
showing  signs  of  wear  and  continued 
performing  satisfactorily  beyond  this 
point.  The  gears  ran  silently,  smoothly, 
without  lubrication,  and  without  atten- 
tion. Moreover,  it  was  found  that  gear 
center  distances  and  other  pertinent  tol- 
erances were  not  nearly  as  critical  as  in 
the  case  of  fabricated  gears.  This  al- 
lowed ready  assembly  in  the  factory  and 
replacement  in  the  field  without  critical 
adjustment  which  would  otherwise  result 
in  "whine"  when  fabricated  gears  were 
used. 

Various  Advantages  Cited 

The  problem  of  a  uniform  supply  of 
gears  was  therefore  solved  when  the 
gear  molds  were  ordered.  The  further 
advantage  of  a  cost  reduction  of  50% 
or  more  as  compared  with  other  fabri- 
cated gears  was  also  realized.  Since  it 
is  known  that  molded  gears  have  a 
tougher  outer  skin  than  gears  cut  from 
rod,  it  is  fully  expected  that  even  better 
service  will  be  obtained  than  from  the 
gears  cut  from  rod  stock. 

The  daily  accumulation  of  data  on 
the  new  train  of  gears  encourages  engi- 
neers to  say  "Long  life  to  nylon." 

Is  Aural  Acuity  Diminishing? 

The  results  of  the  survey  conducted  some 
time  ago  as  to  fidelity  preferences  was  very 
interesting.  It  seems  amazing  that  people 
should  prefer  imperfect  reproduction,  and 
thus  miss  much  of  the  true  quality  of  music. 

Since  its  inception  more  than  25  years 
ago,  radio  broadcasting  has  come  to  such  a 
point  that  many  people  do  their  musical 
listening  almost  entirely  through  it.  Thus 
they  learn  music  not  as  it  really  is,  but  as  an 
essentially  imperfect  instrument  repro- 
duces it. 

No  popular-priced  sets  have  fidelity  much 
better  than  100-8000  c.p.s.  and  very  few  are 
better  than  200-5000.  Thus  when  people 
are  confronted  with  a  system  with  a  range 
of  50-10,000  c.p.s.  or  better,  they  are  not 
familiar  with  the  new  sensation,  and  prefer 
the  reproduction  to  which  their  ears  have 
become  accustomed. 

This  situation  may  mean  that  aural  dis- 
crimination is  becoming  less  acute,  perhaps 
with  respect  to  such  factors  as  harmonic 
distortion  as  well  as  fidelity.  Consider  also 
that  the  people  tested  were  adults  who  had 
begun  to  feel  the  influence  of  the  radio  only 
relatively  late  in  life. 

What  about  those  of  the  present  genera- 
tion who  have  received  practically  all  of 
their  aural  entertainment  from  radios  and 
phonographs  of  decidedly  doubtful  quality, 
turned  up  far  beyond  the  distortion  point? 
What  about  television  which  is  bringing 
people  even  more  in  contact  with  the  dubi- 
ous quality  of  electronic  sound?  Is  the 
radio  ruining  our  ears? — Audio  Engineer- 
ing. 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


When  "the  dawn  comes  up  like  thunder"... 


HE'S  at  his  console — the  re-record- 
ing mixer — weaving  skeins  of  sound 
into  the  picture's  pattern  .  .  .  skill- 
fully matching  sound  to  sight,  mood 
for  mood. 

Under  his  sensitive  control,  dia- 
logue and  music  and  special  effects 
are  expertly  proportioned,  delicately 
balanced  to  round  out  the  realism 
and  drama  of  the  scene. 


To  fulfill  this  essential  contribu- 
tion to  the  picture,  the  re-recording 
mixer  requires  creative  understand- 
ing of  the  director's  desires  ...  a 
sense  of  the  dramatic ...  a  feeling 
for  mood  . . .  and  the  high  order  of 
faithful  sound  reproduction  and  re- 
recording  he  gets  from  the  large  and 
versatile  family  of  Eastman  motion 
picture  films. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.    Y. 

J.  E.   BRULATOUR,   INC.,   DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •    HOLLYWOOD 


N\N 


/// 


/<. 


m 


THE  STRONG  MOGUL 

PROJECTION      ARC      LAMP 

PROJECTS  THE  MAXIMUM  LIGHT  THAT  FILM  WILL   ACCEPT  WITHOUT  DAMAGE 


USE  THIS  COUPON  TODAY  FOR  DEMONSTRATION  OR  LITERATURE 


THE  STRONG  ELECTRIC  CORPORATION 

"The  World's  Largest  Manufacturer  of  Projection  Arc  Lamps" 
[I    31    City  Park  Avenue  Toledo  2,  Ohio 

[~"1  I  would  like  a  demonstration  of  Strong  lamps  in  my  theatre,  without  cost 
or  obligation. 
Please  send  free  literature  on  the: 

□  Mogul  Lamp  □  Utility  1  K.W.H.I.  Lamp  □  Strong  Rectifiers 

|~~]  Strong  Reflectors  Q  Strong  Arc  Spotlamps 

NAME — 


WtortkizmfHtm  STRONG  tAejoidutei*  < 


THEATRE- 
STREET — 


I 
I 
I 
I 
I 
I 

i 

i 

I 


CITY  AND  STATE- 


Addenda:  'Matched'  Projector  Optics 

The  wealth  of  article's  anent  projection  optics  appearing  in  recent  issues  of  IP 
has  attracted  world-wide  attention  within  cinematographic  technical  circles. 
Certainly  not  the  least  articulate  is  the  estimable  R.  H.  Cricks,  Technical 
Editor  of  "Ideal  Kinema"  (London),  whose  observations  are  appended  hereto. 


By  R.  H.  CRICKS 

AN  illuminated  object  upon  which 
a  camera  is  focused  is  reflecting 
light  in  all  directions,  and  the  bigger  the 
lens  the  more  of  this  light  it  will  collect. 
Is  this  still  true  of  a  projection  lens?  It 
remains  true  only  so  long  as  the  lens  is 
not  picking  up  all  the  light  passing 
through  the  film. 

Consider  Fig.  1:  obviously  the  smaller 
lens  is  not  picking  up  all  the  light  in  the 
beam  from  the  mirror,  consequently  any 
increase  in  lens  aperture  will  increase 
the  amount  of  light  reaching  the  screen. 
If  on  the  other  hand  the  lens  were  of 
larger  diameter,  as  shown  in  dotted  lines, 
it  would  be  picking  up  the  whole  of  the 
directly  transmitted  beam,  and  any  fur- 
ther increase  in  diameter  would,  on  the 
face  of  it,  result  in  passing  no  more  light. 
This  may  not  be  strictly  true,  but  for  the 
moment  we  will  accept  it. 

Focal  Length  or  Working  Distance 

Let  us  next  turn  to  the  arc  mirror.  By 
analogy  with  the  lens  the  mirror  may  be 
given  an  F  value,  which  is  frequently  cal- 
culated as  the  working  distance  W1  divi- 
ded by  the  diameter  (Fig.  1).  But  obvi- 
ously it  is  more  correctly  expressed  as 
W,  :  D.  Naturally,  we  should  not  speak 
of  focal  length,  as  in  the  case  of  a  lens, 
because  the  mirror  never  works  at  infin- 
ity; working  distance  is  the  correct  term. 

[Note:  Mr.  Mitchell  is  in  complete 
accord  with  Mr.  Cricks  on  this  point, 
and,  in  fact,  holds  that  Mr.  Cricks  has 
expressed  the  matter  in  substantially 
more  accurate  form  than  he  did.^ 

The  facile  argument  commonly  used 
is  that  a  mirror  of  F:2  matches  a  lens  of 
F:2,  and  that  we  then  secure  maximum 
efficiency.    Is  this  correct? 

Geometry  proves  that  this  is  perfectly 
true  for  the  center  of  the  gate  aperture. 
But,  equally,  Fig.  1  proves  that  it  is  far 


FIGURE  1 

from  being  the  case  when  we  have  to 
deal  with  an  aperture  whose  diagonal  is 
about  one  inch.  The  effect  of  using  a 
lens  of  an  F  value  the  same  or  less  than 
the    mirror   must   be   to    accentuate   the 


falling  off  of  illumination  at  the  edges 
and  corners  of  the  screen,  or  as  it  is 
properly  termed,  the  vignetting  effect. 

This  would  seem  to  be  the  case  even 
if  we  assumed  that  the  projector  aperture 
were  illuminated  evenly.  But  in  point 
of  fact  it  is  not.  An  interesting  experi- 
ment is  to  place  a  torch  bulb  in  front  of 
a  mirror,  in  the  position  of  the  positive 
crater,  and  view  the  mirror  through  an 
aperture  placed  at  the  working  distance. 

It  will  be  found  that  when  viewed  cen- 
trally the  whole  of  the  mirror  will  be 
"flashed,"  or  filled  with  light,  except, 
perhaps,  for  the  extreme  edges;  but  a 
half-inch  movement  of  the  eye  will  cause 
the  image  of  the  lamp  filament  to  move 
in  the  opposite  direction  on  the  mirror, 
with  the  effect  that  one  side  of  the  mirror 
will  appear  unilluminated. 

What  does  this  prove?  It  proves  that 
the  edges  of  the  picture  are  illuminated 
chiefly  by  rays  of  light  from  the  edges 
of  the  mirror.  If,  therefore,  our  lens 
aperture  is  too  small  to  pick  up  all  these 
marginal  rays,  the  effect  of  vignetting 
will  be  considerably  greater  than  Fig.  1 
would  suggest. 

The  American  Viewpoint 

Articles  have  appeared  recently  in  the 
American  press  (meaning  IP,  of  course 
— Ed.)  seeking  to  apply  orthodox  optical 
formulae  to  the  solution  of  this  problem. 
The  results  obtained  from  these  formu- 
lae indicate  the  entire  impossibility  of 
meeting  the  requirements. 
"  One  factor  of  which  these  formulae 
take  no  account  is  the  phenomenon 
known  as  eclipsing.  If  one  looks  centrally 
at  the  rear  glass  of  a  lens,  one  can  see 
the  whole  of  the  front  glass,  or  on  older 
lenses,  of  the  stop.  But  if  one  looks  at  it 
off-centre,  part  of  the  front  glass — or 
again,  of  the  stop — is  hidden  by  the 
mount.  It  follows  that  the  lens  will  pass 
more  light  from  the  central  part  of  the 
aperture  than  from  the  edges. 

From  these  arguments  it  would  seem 
logical  to  suggest  that  projection  lenses 
should  no  longer  be  rated  in  F  values. 
What  matters  is:  (1)  the  actual  diameter 
of  the  back  glass;  (2)  the  back  focal 
distance  B  in  Fig.  2;  (3)  the  ability  of 
the  lens  to  pass  the  beam  of  light  from 
a  mirror  of  given  F  value  when  the  back 
glass  is  completely  filled, 

None  of  these  factors  can,  as  far  as 
my  limited  optical  knowledge  goes,  be 
ascertained  by  orthodox  optical  for- 
mulae. A  basis  of  calculation  is  indi- 
cated in  Fig.  2,  which  is  an  enlargement 
of  the  right-hand  section  of  Fig.  1. 


The  lens  must,  according  to  our  pres- 
ent requirements,  be  capable  of  collect- 
ing the  whole  of  the  light  contained  in  a 
cone  whose  apex  is  not  the  surface  of  the 
film  but  the  crossover  point  of  the  mar- 
ginal rays  behind  the  film. 

If  we  approximate  our  film  frame  di- 
agonal to  1  inch,  the  distance  of  this 
point  behind  the  film  will  be  equal  to  F 
inches,  F  being  the  speed  of  the  mirror. 
If  B  is  the  back  focus  of  the  lens,  the 
distance  from  the  apex  of  the  cone  to 
the  lens  will  be  B  +  F  inches.  The 
necessary  diameter  L  of  the  lens  will  be: 


B  +  F 


L  = 


If  we  assume  a  mirror  having  a  speed 
of  F:2  and  a  lens  with  a  back  focus  of 
\x/l  inches,  we  find  that  the  necessary 
diameter  of  the  back  glass  of  the  lens 
will  be: 


1%  +  2 


1%  in. 


A  few  existing  lenses  may  possibly  meet 
this  requirement,  while  the  F:1.4  lens, 
which  is  foreseen  in  this  specification  as 
a  design  of  the  future,  should  certainly 
do  so,  having  a  maximum  back  diameter 
of  3.15  inches. 

In  putting  forth  these  views  I  am  in 
no  sense  seeking  to  instruct  opticians  in 
their  craft.  All  these  factors  are  well 
known  to  optical  computers.  In  spite 
of  this,  they — or  should  I  say  the  pub- 
licity experts? — continue  to  rate  lenses 
in  F  numbers,  a  characteristic  which,  as 
I  have  shown,  has  little  or  no  bearing 
upon  the  suitability  of  a  lens  for  a  given 
optical  system. 

[Note:  Mr.  Mitchell  is  definitely  not 
in  agreement  with  the  computations  given 
by  Mr.  Cricks  above,  and  he  also  holds 
that  F  numbers  are  absolutely  necessary 
for  geometric  computations. — Ed.] 

Stray  Light  Losses 

I  have  so  far  omitted  yet  another  fac- 
tor. I  have  assumed  that  all  the  light 
falling  upon  the  film  passes  straight 
through  it,  as  shown  in  the  sketches.  We 
all  know  this  is  not  the  case;  if  it  were, 


FIGURE  2 

then  one  could  look  sideways  at  the  cellu- 
loid side  of  the  film  in  the  projector  gate 
and  see  the  whole  of  the  frame  black. 
The  bright  spot  of  light  which  we  actu- 
ally see  is  due  to  the  dispersion  of  light, 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


11 


chiefly  by  the  silver  particles  of  the 
optical  image. 

It  is  obviously  not  practicable  to  col- 
lect much,  if  any,  of  this  stray  light.  But 
if  it  were,  would  it  be  desirable?  I 
rather  think  not. 

The  incident  light  is  dispersed  more 
by  the  particles  of  silver — that  is,  by  the 
blacks  of  the  image — than  by  clear  film. 
The  effect  of  stray  light  is  therefore  to 
degrade  the  blacks  of  the  picture  and  to 


reduce  the  contrast.  If,  therefore,  the 
lens  were  to  pick  up  much  of  this  stray 
light,  it  would  produce  a  brighter  picture 
at  the  expense  of  contrast.  To  carry  the 
argument  a  step  farther,  it  is  logical  to 
suggest  that  the  bigger  the  lens  aperture 
the  lower  the  contrast  in  the  projected 
image. 

[Note:    Mr.  Mitchell  does  not  agree 
with  this  contention  on  the  basis  that  the 


Stilb'  and  Other  Irritants  Reduced  to  Americanese 


The  use  of  designations  other  than  the 
familiar  "footcandle"  and  "footlambert" 
and  "lumen"  evidently  is  a  source  of 
minor  irritation  to  not  a  few  IP  readers, 
according  to  several  recent  communica- 
tions bearing  on  this  topic.  IP  has  long 
recognized  this  feeling  on  the  part  of  its 
readers,  but  occasionally  it  slips  up  and 
fails  to  provide  the  proper  factor  for 
conversion  into  good  old  Americanese. 

A  case  in  point  was  the  use  (sans  con- 
version factor)  in  our  April  issue  (p.  29) 
of  the  term  "stilb"  in  an  abstract  of  an 
SMPE  paper  issuing  from  the  Philips 
Lamp  Works  in  Holland.  Correspon- 
dents suggest  that  if  IP  just  must  use 


such  terms  as  "stilb"  and  other  unfamiliar 
designations,  the  proper  conversion  fac- 
tor be  given. 

No  sooner  suggested  than  done;  and 
as  a  well-rounded  service  of  a  more  or 
less  permanent  nature  IP  publishes  the 
accompanying  inclusive  table  of  conver- 
sion factors  which  not  only  deals  with 
"stilb"  but  with  all  other  lighting  unit 
designations. 

In  future  IP  will  exercise  the  utmost 
care  to  supply  via  a  footnote  the  proper 
conversion  factor;  but  if  human  frailty 
should  prevail  over  the  best  of  intention, 
it  may  not  be  said  that  nobody  suggested 
permanent  retention  of  the  accompanying 
table. 


CONVERSION  FACTORS  FOR  LIGHTING  UNITS 


ILLUMINATION 


1  lumen  =   1/650  lightwatt 

1  lumen-hour   =   60  lumen-minutes 

1  footcandle   =    1  lumen/sq.ft. 


1  watt-second  =  107  ergs 
1  phot  =  1  lumen/sq.cm 
1  lux  =  1  lumen/sq.M  =  1  meter-candle 


Number  of          ^ 
Multiplied  by 

Equals  Number  of      ^ 

FOOTCANDLES 

LDX 

PHOT 

MILLIPH0T 

1 
10.76 
0.00108 
1.076 

0.0929 

1 

0.0001 

0.1 

929 
10,000 

1 
1,000 

0.929 

10 

phot 

0.001 

1 

BRIGHTNESS 

1  stilb  =   1  candle/sq.cm 

1  apostilb    (international)    =   0.1  millilambert  =   1  blondel 

1  apostilb   (German  Hefner)    =  0.9  millilambert 


Number  of->  FOOT- 
LAMBERT 


Multiplied  by, 
Equals  No.  of 


1 


iJ 


Footlambert  . 

Lambert  

Millilambert 
candle/sq.in. 
candle/sq.ft. 
Stilb 


1 

0.00108 

1.076 

0.00221 

0.3183 

0.00034 


LAMBERT 


929 

1 

1,000 

2. 

295. 

0, 


054 

7 

3183 


MILLI- 
LAMBERT 


0.929 

0.001 

1 

0.00205 

0.2957 

0.00032 


CANDLE/ 
SQ.IN. 


452 

0.487 
487 

1 
144 

0.155 


CANDLE/ 
SQ.FT. 


3.142 

0.0034 

3.381 

0.00694 

1 

0.00108 


STILB 


2,919 

3.142 
3,142 

6.45 
929 

1 


INTENSITY 


center  of  a  lens  does  not  collect  dispersed 
light. — Ed.] 

Another  factor  of  a  purely  mechanical 
nature  which  I  have  omitted  is  the  smaller 
depth  of  focus  of  a  wide-aperture  lens. 
The  effect  of  this  is  that  film  buckle  be- 
comes more  noticeable  with  a  wide- 
aperture  lens,  and  if  such  lenses  are  to 
be  used,  the  avoidance  of  film  buckle  by 
the  use  of  a  curved  gate  is  essential. 

Summarization  of  Findings 

We  may  summarize  this  finding  as 
follows:    (1)   The  F  number  of  the  mir- 

w, 

ror  must  be  calculated  not  as  but 


D 


D 


-;   (2)   a  lens  of  the  same  F  value 


1  international  candle  =   1  bougie  decimale   =   1.11  Hefner  Kerze 


will  give  the  maximum  brightness  at  the 
centre  of  the  image,  but  serious  vignet- 
ting at  the  edges;  (3)  optimum  results 
—brightness  and  edge-to-center  ratio — 
will  be  secured  by  a  lens  having  a  back 
glass  of  diameter  L,  as  shown  in  Fig.  2, 
and  capable  of  transmitting  the  whole 
of  the  cone  of  light  received  from  the 
gate  aperture,  whose  apex  is  the  cross- 
over point  of  the  marginal  rays  behind 
the  film;  (4)  a  lens  of  still  larger  dia- 
meter will  pick  up  no  more  directly  trans- 
mitted light  and,  by  picking  up  stray 
light,  will  merely  degrade  the  projected 
image. 

[Immediately  following  are  Mr.  Mitchell's 
observations  on  the  comment  by  Mr. 
Cricks,  with  particular  reference  to  the 
general  formula  advocated  by  the  former.] 

By  ROBERT  A.  MITCHELL 

AT  the  outset  I  must  disagree 
with  Mr.  Cricks's  disparagement 
of  the  F-number  system  of  rating 
the  "speeds"  of  projector  lenses.  It  is 
true  that  this  rating  system  is  geometric 
rather  than  optical,  but  for  this  very  rea- 
son it  must  be  retained.  Optical  match- 
ing is  basically  a  matter  of  geometry; 
and  such  optical  refinements  tending  to- 
ward the  attainment  of  maximum  picture 
brightness,  optimum  image  contrast,  and 
uniformity  of  illumination  must  conform 
to  the  basic  geometric  requirements. 

It  is  curious  that  Mr.  Cricks  should  de- 
velop his  soundest  arguments  along  geo- 
metric lines  only  to  brush  them  aside 
with  the  statement:  "In  spite  of  this, 
they — or  should  I  say  the  publicity  ex- 
perts?— continue  to  rate  lenses  in  F- 
numbers — a  characteristic  which,  as  I 
have  shown,  has  little  or  no  bearing  on 
the  suitability  of  a  lens  for  a  given  op- 
tical system."  Still  more  curiously,  Mr. 
Cricks  utilizes  the  utterly  false  F -number 
ratings  of  condensing  elements  (mir- 
(Continued  on  page  29) 


12 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


and  make  box  office 


wnA.  /-  /./.V/  /../, 


» 


"National" M.I.  Arc 
"Brightest  spot 
in  the  world ! 


The  term  "National " 
is  a  registered  trade  ■  mark  of 

NATIONAL  CARBON  COMPANY,  INC. 

Unit  of 
Union  Carbide  and  Carbon  Corporation 

GH3 

30  East  42nd  Street,  New  York  17,  N.Y. 

Division  Sales  Offices: 

Atlanta,  Chicago,  Dallas,  Kansas  City, 

New  York,  Pittsburgh,  San  Francisco 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


13 


FIG.  1 — Experimental    lamp    with    probes    for    measuring    the 
net    arc    voltage,   without  water  cooling. 


FIG.  2 — Experimental  lamp  with  water  jackets  and  probes. 


The  Effect  of  Carbon  Cooling  on 

High  Current  Arcs* 


WATER-COOLING  of  the  positive 
as  well  as  the  negative  carbon 
of  high-intensity  carbon  arcs  has 
proved  to  be  of  great  advantage  in  cases 
where  highest  brightness,  and  therefore 
highest  current  density,  is  desired.  A 
systematic  study  of  the  influence  of  water 
cooling  on  the  properties  of  the  arc  and 
its  mechanism  therefore  seemed  desirable 
and  has  been  carried  out  at  the  Engineer 
Research  and  Development  Laboratories 
by  the  author  with  the  help  of  L.  R. 
Noffsinger  and  C.  Orr,  using  an  excellent 
new  super  high-intensity  experimental 
carbon  of  11-mm  diameter  (No.  070) 
manufactured  for  this  service  by  the 
National  Carbon  Co. 

Method  of  Measuring 

The  measurements  were  made  with  a 
Mole-Richardson  lamp  (Figs.  1-3)  which 
has  a  carbon  angle  of  52  degrees.  The 
lamp  was  designed  for  automatic  feeding 
but  for  these  studies  it  was  changed  to 
hand-controlled  feeding. 

The  carbons  were  cooled  by  copper 
jackets  through  which  water  was  circu- 
lated,  and  which  enclosed   the   carbons 


By  WOLFGANG  FINKELNBURG 

Research  and  Development  Laboratories,  Fort  Belvoir,  Virginia 


t  J.   Soc.  Mot.  Pict.  Eng.,  April,   1949,   p.  407. 


near  their  burning  ends  (Fig.  2).  The 
carbons  protruded  from  these  water 
jackets,  through  holes  only  slightly 
larger  than  the  carbons,  a  distance  of 
approximately  7  mm  for  the  positive, 
and  approximately  20  mm  for  the  nega- 
tive carbon. 

Water  jackets  in  the  form  of  semi- 
circular jaws,  pressed  from  both  sides 
against  the  carbons,  would  offer  certain 
technical  advantages ;  however,  they  were 
not  used  for  this  investigation,  because 
of  the  difficulty  of  manufacture. 

For  comparison  of  measurements  of 
water  cooling  with  forced-air  cooling,  a 
copper-finned  head  (Fig.  3)  was  used. 
This  head  was  cooled  with  compressed 
air  and  served  to  prove  that  identical 
effects  could  be  achieved  by  cooling  the 
positive  carbon  with  compressed  air  as 
with   water.     For   the   essential    set   of 


FIGURE    3 

Experi- 
mental 
lamp    with 
probes    and 

copper- 
finned  head 
for  forced- 
air    cooling. 


measurements,  9-mm  copper-coated  nega- 
tive carbons  were  used  with  the  11-mm 
positive  carbons;  the  arc  length  of  18 
mm  was  kept  constant  by  observing  a 
greatly  magnified  image  of  the  arc,  with 
marks  for  the  desired  position  of  the 
carbon  tips. 

A  pointer,  attached  to  the  rear  end 
of  the  positive  carbon,  permitted  its 
length  to  be  measured  on  a  mm  scale 
during  the  operation  of  the  arc.  Thus, 
with  a  stop  watch,  the  rate  of  consump- 
tion of  the  positive  carbon  could  be 
measured.  This  was  done  as  soon  as  a 
stationary  state  of  operation  had  been 
reached  for  each  respective  current. 

The  gross  voltage  of  the  arc,  including 
the  voltage  drop  in  the  carbon  tips,  was 
measured  by  connecting  the  voltmeter 
across  the  carbons  at  the  water-cooled 
heads  for  the  cooled  arc,  and  at  the 
negative  clamp  and  the  positive  brush 
for  the  uncooled  arc.  In  order  to 
measure  the  net  arc  voltage,  two  carbon 
probes  (Figs.  1  through  3)  could  be 
made  to  touch  the  carbon  tips  near  the 
burning  ends  by  means  of  a  magnetic 
relay.  The  crater  depth  was  measured 
by  means  of  a  special  gauge,  while  the 
crated  diameter  was  measured  with  a 
standard  caliper.  The  crater  brightness 
was  measured  by  projecting  the  crater 
image  with  a  lens  of  known  aperture  on 
a  photosensitive  cell. 

While  the  current  and  arc  length  were 
kept  constant  with  utmost  care,  voltage, 
crater  brightness,  and  positive-carbon 
consumption  were  measured  simultane- 
ously and  recorded  as  averaged  over  2- 
minute  runs.    After  each  run  the  crater 


14 


INTERNATIONAL  PROJECTIONIST 


June  1949 


DOUBLE-BEARING  INTERMITTENT- A 

perfect  example  of  unit-design.  The 
entire  mechanism  is  precision -as- 
sembled as  a  unit.  Accuracy  (to 
1/10,000  in.)  of  this  intermittent  is 
maintained  in  operation  by  double 
bearings,  three  times  usual  area,  and 
automatic  splash  lubrication  — with 
same  oil  (1  pint)  that  flows  over 
whole  projector  mechanism. 


FOOLPROOF  FRAMING  -Brenkert's 
framing  unit  is  unique  .  .  .  all  gears 
are  in  constant  mesh  in  any  framing 
position.  Smoother  and  quieter  op- 
eration .  .  .  much  longer  life  .  .  .  and 
again  —  automatically  lubricated! 


ow  VHIT-COHSTRUCTIOH  of  the  BRENKERT  "80"  makes  your  job  easier 


Wide  fan.  tk&ie  BaoMeU 


They're  Yours  for  the  Asking 

Send  for  free  copies  of  booklets  illus- 
trating and  describing  the  operating 
mechanism  of  the  Brenkert  "80"  and 
the  Brenkert  "60"  Projectors.  Write 
to:  Theatre  Equipment,  Dept.  47F, 
RCA,  Camden,  New  Jersey. 


The  Brenkert  "80"  Projector  is  a  masterpiece 
of  accurate  sub-assembly  construction  for  easy 
replacement  of  parts.  It  is  easier  to  operate  .  .  . 
and  far  simpler  to  maintain  than  any  other  pro- 
jector used  in  modern  theatres  and  drive-ins. 

As  an  example,  you  can  remove  and  replace 
the  entire  intermittent  assembly— and  re-time 
the  shutter— in  less  time  than  it  takes  to  run  off 
a  single  reel !  The  intermittent  sprocket  can  be 
replaced  in  one  minute  flat  without  disturbing 


the  intermittent  mechanism  or  projectortiming. 

Other  time-saving  advantages :  the  film  gate 
assembly  is  held  by  only  one  hand  screw,  ac- 
curately aligned  by  two  pins.  One  master  screw 
adjusts  all  gate  springs  at  once  with  uniform 
tension.  The  aperture  plate  slides  out  instantly 
for  cleaning. 

All  Brenkert  parts  are  assembled  by  units,  in 
the  same  easy-to-get-at  way— making  your  job 
easier— requiring  less  time  for  maintenance. 


THEATRE  EQUIPMENT 

RAD tO    CORPORATION  of  AMERICA 

ENGINEERING  PRODUCTS  DEPARTMENT.  CAMDEN.  N.J. 

In  Canada:  RCA  VICTOR  Company  Limited,  Montreal 


1800 
1600 

*  1400 

o 

< 

o  IZ00 

z 

S7 

<*y 

X 

f 

< 

ARC    CURRENT    IN  AMPERES 


FIG.  4 — Comparison  of  crater  brightness  of 
cooled   and    uncooled   arcs   at   equal   currents. 

depth  was  measured.  During  the  first 
tests,  the  crater  diameter  also  was  meas- 
ured, but  this  was  discontinued  since  it 
remained  constant  at  11  mm  for  the 
water-cooled  arc,  and  was  from  0.1  to  0.2 
mm  smaller  for  the  uncooled  arc. 

General  Properties  of  Cooled 
and  Uncooled  Arcs 

Comparison  of  arcs  without  carbon 
cooling,  with  water-cooling  of  both  car- 
bons and  with  exclusive  cooling  of  either 
the  positive  or  the  negative  carbon,  re- 
vealed that  water-cooling  increased  the 
steadiness  of  the  arc  and  of  its  radiation 
considerably.  Cooling  of  the  negative 
carbon  alone  had  no  effect  other  than 
that  of  steadying  the  arc;  while  cooling 
of  the  positive  carbon  increased,  to  a 
great  extent,  not  only  the  steadiness  of 
the  arc,  but  also  changed  important 
properties  of  the  arc,  such  as  arc  volt- 
age and  positive-carbon  consumption. 
Furthermore,  water-cooled  carbons,  espe- 
cially if  designed  for  this  kind  of  opera- 
tion, reached  a  much  higher  brightness 
than  uncooled  ones. 


With  the  best  uncooled  11-mm  car- 
bons, sputtering  and  hissing  of  the  arc 
began  at  a  brightness  of  approximately 
1500  candles  per  sq.  mm;  while  steady 
operation  of  the  same  carbons,  when 
water-cooled,  was  possible  up  to  a  bright- 
ness of  1850  candles  per  sq.  mm.  From 
all  measurements  the  conclusion  seems 
to  be  inevitable  that  cooled  positive  car- 
bons behave  quite  differently  in  the  high- 
current  carbon  arc  than  do  uncooled 
ones,  in  which  each  part  is  heated  to  a 
very  high  temperature  before  the  arc 
reaches  it.  A  detailed  study  of  the 
changes  in  the  carbon  core  resulting 
from  this  heating  is  under  way. 

A  quantitative  comparison  of  the  prop- 
erties of  the  high-current  carbon  arc 
with  cooled  and  uncooled  070  carbons 
is  presented  in  Figs.  4  through  12,  in 
which  averaged  results  of  a  large  num- 
ber of  measurements,  carried  out  with 
many  samples  of  070  carbons,  are 
plotted. 

Figure  4  shows  one  of  the  most  un- 
expected effects  of  cooling  the  positive 
carbons:  for  all  currents  the  net  arc 
voltage  (as  measured  with  the  probes 
between  the  carbon  tips)  is  considerably 
lower  than  without  cooling,  no  matter 
whether  the  negative  carbon  is  cooled 
or  not.  As  the  arc  stream  is  independ- 
ent of  the  positive  carbon,  it  seems  safe 
to  conclude  that  this  decrease  of  the 
arc  voltage  is  caused  by  a  decrease  of 
the  anode  drop,  and  this  conclusion  is 
in  agreement  with  earlier  investigations. 

According  to  the  theory  of  arc  radia- 
tion, developed  in  connection  with  the 
anode-drop  work,  a  decrease  of  the  anode 
drop  always  causes  a  decrease  of  the 
crater  brightness.  Fig.  5  proves  that 
water-cooling  of  the  positive  carbon  ac- 
tually does  cause  a  considerable  reduc- 
tion of  the  crater  brightness  at  the  same 
current. 


ARC    CURRENT   IN    AMPERES 

FIG.  5 — Decrease  of  net  arc  voltage  caused  by 
cooling  of  positive  carbon    (same  arc   length). 

In  Fig.  6,  the  crater  brightness  is 
plotted  against  the  arc  wattage.  The 
middle  curve  refers  to  the  water-cooled 
arc  (where  the  difference  between  the 
net  arc  wattage  and  the  gross  arc  watt- 
age falls  within  the  limits  of  accuracy 
of  our  measurements  because  the  carbon 
protrusions  are  short),  while  the  upper 
and  lower  curves  are  plotted  against  the 
net  arc  wattage  and  the  gross  wattage  of 
the  uncooled  arc. 

For  a  given  net  arc  wattage  the  un- 
cooled arc  gives  a  higher  brightness  than 
the  water-cooled  arc;  while  a  given 
gross  wattage,  actually  dissipated  in  the 
arc  and  the  carbons  from  the  negative 
clamp  to  the  positive  brush,  results  in  a 
higher  brightness  for  the  water-cooled 
arc. 

Light  Efficiency  Data 

Relative  to  the  total  light  efficiency, 
measured  for  convenience  in  candles  per 
watt  gross  arc  wattage,  the  uncooled  arc 
is  always  superior  to  the  water-cooled 
arc,  as  may  be  seen  from  Figs.  7  and  8, 
in  which  the  efficiency  in  candles  per 
watt  is  plotted  against  the  gross  arc 
wattage  and  brightness,  respectively. 

With  reference  to  the  gross  arc  watt- 


FIG.  6  (left):    Comparison  of  crater  brightness  of  cooled  and  uncooled  arcs  for  equal 

net  and  gross  arc  wattages. 
FIG.  7  (center):     Comparison    of    light    efficiencies    of   cooled    and    uncooled    arcs    for 

equal  gross  arc  wattages. 
FIG.  8  (right):     Comparison    of    light    efficiencies    of    cooled    and    uncooled    arcs    for 

equal  crater  brightness. 


ARC    WATTA0E    IN  KW 


GROSS    ARC  WATTAGE  IN  KW 


•00  IO0O  1*00  I40O 

CRATER   IRICHTNESS     IN    CANDLES/MM* 


16 


INTERNATIONAL  PROJECTIONIST 


June  1949 


CO 

3 

o 

*     80 

X 

Z      40 

o 
a. 

» 

V 

Y 

« 

m     30 
O 

z 
o 

a     20 

> 

g      10 

a 

•OO  1000  1200  MOO  WOO 

CRATER     BRIGHTNESS     IN  CANDLES  /  MM  2 


a. 
o&O 

i 

-40 

Z 

,       . 

• 

x^' 

a 

y^ 

z 
o 

z 
o 
£zo 

1      " 

•  • 

> 

li-^* 

0. 

FIG.  9 — Comparison     of    positive-carbon     consumption     of 
cooled    and    uncooled    arcs    for    equal    crater    brightness. 


CRATER     BRIGHTNESS     IN  CANDLES    /  MM  * 

FIG.  10 — Increase  of  positive-carbon  consumption  with  crater  brightness. 


age,  the  difference  is  about  12%,  while 
with  reference  to  the  same  crater  bright- 
ness it  is  only  approximately  6%.  This 
slightly  lower  light  efficiency  of  the 
water-cooled  arc  probably  is  caused  by 
the  fact  that  the  water  carries  away  part 


of  the  energy  transferred  to  the  positive 
carbon  by  the  arc. 

The  most  important  feature  of  the 
water-cooled  arc,  next  to  its  superior 
steadiness  at  highest  brightness,  is  its 
low  positive-carbon  consumption  as  seen 


from    Fig.    9,    where    consumption    is 
plotted  against  crater  brightness. 

Compared    with    other    carbons,    the 
consumption  of  the  experimental  carbon 
No.  070  is  very  low  even  without  water- 
(Continued  on  page  28) 


ETTERS    TO    THE    EDITOR 


&fi 


To  the  Editor  of  IP: 

Though  belated,  we  trust  that  this 
comment  will  lose  none  of  its  emphasis 
thereby.  In  your  November  1948  issue 
there  appeared  an  article  "Safety  Film: 
Projection  Factors"  which,  under  the 
subhead  "Procedure  Governs  Results" 
on  page  14,  contains  a  statement  which 
we  consider  erroneous.  We  quote:  "Fre- 
quent adjustment  of  this  splicer  (the 
Griswold)  is  advisable  because  of  the 
shear  blade  positioning." 

This  statement  is,  we  think,  very  mis- 
leading because  it  does  not  explain  why 
the  positioning  of  the  shear  blade  re- 
quires frequent  adjustment,  nor  does  it 
state  just  what  adjustments  should  be 
made. 

Field  Adjustments  vs.  Warranty 

As  the  manufacturer  of  this  splicer, 
we  stress  the  fact  that  adjustments  of  any 
nature  are  unnecessary  and  should  not 
be  attempted  in  the  field.  These  splicers 
are  set  up  at  the  factory  with  special 
fixtures  and  aligning  tools,  not  available 
on  the  outside,  and  an  attempt  at  adjust- 
ment in  the  field  will  tend  to  throw  the 
entire  unit  out  of   alignment. 

As  a  matter  of  fact,  adjustments  such 
as  you  recommend  would  void  the  liberal 
guarantee  anent  performance  which  we 
extend  for  one  year  from  the  date  of 
purchase. 

Griswold  Machine  Works 

[The  section  in  the  article  referred  to 
was  a  bit  misleading  and  might  well  have 


been  stated  somewhat  differently — simply  a 
matter  of  interpretation.  Instead  of  saying 
that  when  the  center  bar  of  the  splicer  be- 
comes etched  it  will  tend  to  wear  the  cor- 
ners of  the  film,  IP  might  have  more  accu- 
rately stated  that  such  etching  would  tend 
to   give   an   uneven   scraping  surface. 

By  "frequent  adjustment,"  the  phrase  to 
which  our  correspondent  especially  objects, 
IP  could  have  indicated  that  it  was  not  so 
much  the  positioning  of  the  shear  blade  but 
rather  its  surface  condition  which  formed 
the  basis  of  efficient  performance.  It  might 
have  been  specifically  stated  that  if  the  shear 
blade  becomes  etched,  it  should  be  either 
replaced  or  resurfaced  to  give  a  truly  flat 
scraping  surface. 

As  for  the  balance  of  the  article  relating 
to  splicing  technique,  it  is  readily  admitted 
that  very  few  projectionists  replace  scraper 
blades  after  25  scrapes;  but  IP  still  thinks 
the  practice  a  good  one  for1  optimum  results. 
After  all,  if  IP  doesn't  shoot  for  the  stars,  it 
will  be  put  in  the  position  of  tolerating,  if 
not  actually  advocating,  minimum  rather 
than  optimum  standards. 

In  passing,  it  might  be  observed  that  when 
IP  is  read  so  assiduously  and  so  much  im- 
portance is  attached  to  a  single  paragraph 
in  a  rather  lengthy  article,  it  is  surprising 
that  all  enterprising  manufacturers  do  not 
avail  themselves  of  such  tremendous  reader 
interest. — Ed. 

To  the  Editor  of  IP: 

Could  you  tell  me  where  I  could  get  an 
outfit  to  use  in  lining  up  the  optical  sys- 
tem of  the  lamp-projector?  I  have  read 
about  dummy  lenses  and  aligning  rods 
but  have  been  unable  to  locate  any.  I 
am  advised  to  "see  a  dealer,"  but  when 


I   see  a  dealer  he  knows   from  nothing 
about   such  items. 

How  about  these  film  splicers  utilizing 
heaters  to  aid  in  splicing  the  new  safety 
film? 

Oliver  K.  Blain,  Jackson,  Mich. 

[Aligning  rods  for  the  projection  optical 
system  are  such  a  commonplace  of  the  art 
that  IP  assumed  that  every  dealer  worthy  of 
the  name  had  such  equipment.  Inquiry  re- 
veals, however,  that  even  the  largest  supply 
houses  rely  upon  an  eye-view  and  rule-of- 
thumb  system  for  such  alignment. 

Failing  to  obtain  such  a  rod  from  a  sup- 
ply house,  it  is  almost  certain  that  the  serv- 
ice company  field  men  could  come  up  with 
such  a  tool. 

Splicers  with  heating  attachments,  used 
mostly  in  studio  and  laboratory  work,  are 
unnecessary  for  the  effective  splicing  of  the 
new  safety  film.  Detailed  instructions  on 
this  procedure  have  appeared  in   IP. — Ed.] 

To  the  Editor  of  IP: 

I  have  noticed  in  the  technical  litera- 
ture several  references  to  the  Veri-Vision 
system  of  producing  and  showing  stereo- 
scopic motion  pictures  (Veri  Vision 
Holdings,  The  Hague,  Netherlands).  The 
assertion  is  made  that  this  system  is  the 
answer  to  "true"  three-dimensionoal  mo- 
tion pictures.  What's  the  answer  on  this? 
Ray  McAllister,  Los  Angeles,  Calif. 

[The  answer  is  that  the  Veri-Vision  sys- 
tem is  just  another  variation  of  the  con- 
ventional method  of  producing  stereoscopic 
pictures  in  that  it  utilizes  an  analyzer  (col- 
ored spectacles  for  each  viewer)  much  in 
the  same  fashion  as  has  ben  demonstrated 
numerous  times  in  the  past.  The  most  not- 
able stereoscopic  pictures  shown  with  the 
aid  of  an  analyzer  was  the  Audioscopics 
series  produced  by  Jack  Norling  (Loucks  & 
Norling  Studios)    of  New  York  City.— Ed.] 


INTERNATIONAL  PROJECTIONIST 


June  1949 


17 


'^~7~ 


IN  THE 


SPOTLIGHT 


By 

HARRY 

SHERMAN 


WE  HAD  occasion  recently  to  examine  both  State  and  municipal  laws  relat- 
ing to  the  projection  of  motion  pictures  in  theatres.  Oddly  enough,  we 
found  that  the  emphasis  in  these  regulations  is  placed  upon  the  material  used  in 
the  process  rather  than  the  degree  of  craftsmanship  that  is  brought  to  bear  upon 
the  handling  of  these  materials.  Film  and  machinery  are  accorded  precedence  over 
craftmanship,  which  is  a  combination  of  know-how  and  experience. 

Our  thinking  along  this  line  was  crystallized  by  recent  stories  in  the  trade 
press  to  the  effect  that  the  introduction  of  the  new  tri-acetate  film,  the  use  of  which 
is  expanding  rapidly,  constitutes  a  valid  basis  for  requesting  a  reduction  in  pro- 
jection room  manpower.  We  anticipated  just  such  a  reaction  from  penny-pinch- 
ing exhibitors  who  for  years  have  been  more  concerned  with  box-office  intake 
rather  than  the  very  means  which  attracts  that  intake — namely,  the  projected 
image  on  the  screen. 

Noticeably  lacking  in  the  various  regulations  we  examined  is  any  reference  to 
projectionist  competency  based  upon  experience.  Moreover,  we  failed  to  find  a 
single  reference  to  the  extremely  high  voltage  utilized  in  modern  projection  prac- 
tice. There  are  instances  of  record  where  panic  has  been  induced  among  an  audi- 
ence confined  in  darkness  within  four  walls  wherein  not  a  single  frame  of  film 
was  ignited.  A  simple  film  break  which  results  in  a  blank  screen  has  been  known 
to  occasion  noticeable  unrest,  which  is  contagious  among  such  an  audience. 

Of  course,  when  theatre  Tv  comes  into  being,  voltages  will  run  to  60,000  and 
more,  thus  establishing  a  situation  wherein  consideration  of  a  film  fire  will  be 
relatively  unimportant.  Be  that  as  it  may,  our  advice  at  the  moment,  with  all  the 
force  at  our  command,  is  that  those  progressive  union  leaders  who  are  interested 
in  protective  legislation  for  their  members  immediately  take  stock  of  the  present 
legislative  status  in  their  respective  areas  and  move  quickly  and  vigorously  to 
have  such  laws  require  a  proper  recognition  of  the  intricacies  of  the  projection 
process.  No  more  vital  task  confronts  the  progressive  union  official  today!  We 
invite  those  who  desire  more  specific  information  on  this  topic  to  address  this 
department  directly. — H.  S. 


•  The  Rodger  Young  Auditorium  in  Los 
Angeles,  Calif.,  was  the  scene  of  a  testi- 
monial dinner  tendered  recently  to  Dick 
Green,  former  IA  official  and  a  member 
of  Locals  165  (Hollywood,  Calif.)  and 
2  (Chicago  Stagehands).  Grant  John- 
son, president  of  Local  2  planed  in  from 
Chicago  for  the  special  purpose  of  pre- 
senting Dick  with  a  gold  life  member- 
ship card  in  recognition  of  40  years 
meritorious  services  rendered  the  Local. 

Present  at  the  dinner  were  many  mem- 
bers of  the  IA  official  family,  including 
Carl  Cooper,  7th  IA  vice-president;  Roy 
Brewer  and  Steve  Newman,  IA  West 
Coast  representatives,  and  Floyd  Bill- 
ingsley,  3rd  IA  vice-president  and  busi- 
ness manager  for  San  Francisco  Local 
162.  Officers  and  members  of  many 
nearby  Locals  came  to  do  honor  to  one 
of  the  grand  old-timers  in  the  Alliance. 

•  Joe  Cifre,  member  and  former  presi- 
dent of  Boston  Local  182,  received  the 


"Great  Heart  Award"  at  a  luncheon 
given  in  his  honor  by  the  Variety  Club 
of  New  England.  The  luncheon,  held  on 
June  7  at  the  Copley  Plaza  Hotel  in 
Boston,  was  attended  by  many  industry 


leaders.  Joe  was  honored  at  a  citation 
dinner  last  Fall  for  his  work,  while  chief 
barker  for  Variety  Tent  No.  23  (New 
England),  in  raising  more  than  a  quarter 
of  a  million  dollars  for  the  Children's 
Cancer  Research  Foundation. 

•  We  were  happy  to  learn  that  our  very 
good  friend  C.  E.  (Red)  Rupard,  former 
business  manager  for  Dallas  Local  249, 
is  making  steady  progress  in  his  recovery 
from  an  injury  to  his  shoulder.  Enforced 
idleness  is  not  much  to  Red's  liking  and 
he  is  anxious  to  get  back  on  the  job. 

•  Stemming  from  the  elections  held  last 
month,  the  Pennsylvania  Labor  Relations 
Board  certified  IA  Local  B-100  as  collec- 
tive bargaining  agent  for  cashiers,  door- 
men, ushers,  cleaners,  porters,  and  ma- 
trons employed  in  Philadelphia  motion 
picture  theatres.  Paramount,  Fox,  and 
Warner  theatres  are  directly  affected  by 
this  certification. 

•  George  Anderson,  member  of  Mil- 
waukee Local  164  for  the  past  30  years, 
and  Mrs.  Anderson  celebrated  their  25th 
wedding  anniversary  last  month  at  the 
South  Shore  Yacht  Club  in  Milwaukee. 
More  than  150  friends,  including  the 
entire  executive  board  of  Local  164, 
helped  to  make  this  a  gala  event. 

•  Peter  Benard,  69,  member  of  Bridge- 
port Local  277  and  vice-president  of  the 
Connecticut  Federation  of  Labor,  died 
at  his  home  last  month  after  a  long  ill- 


DICK  GREEN  AWARDED  GOLD  LIFE  MEMBERSHIP  CARD  IN  CHICAGO  STAGEHAND  LOCAL 


Grant  Johnson  (center  left),  president  of  Chicago  Stagehand  Local  2  presents  Dick  Green  with 

a  gold  life  membership  card  in  the  Local.    Shown  above,  on  the  extreme  left,  is  Steve  Newman, 

IA  representative,  and  on  the  extreme  right,  Carl  Cooper,  7th   IA  vice-president 


18 


INTERNATIONAL  PROJECTIONIST 


June  1949 


ness.  A  prominent  figure  in  labor  circles 
for  the  past  50  years,  he  helped  organize 
the  Bridgeport  Local  back  in  1912  and 
served  in  an  official  capacity  for  many 
years.  In  April,  1948,  Local  277  spon- 
sored a  testimonial  dinner  for  Pete  and 
presented  him  with  a  gold  life  member- 
ship card. 

In  memory  of  Pete's  deep  interest  in 
educational  opportunities  for  the  girls 
and  boys  of  Bridgeport,  the  Central 
Labor  Union,  of  which  he  was  president 
emeritus,  and  The  Herald,  local  news- 
paper, have  donated  two  scholarship 
funds  of  $500  each  to  the  University  of 
Bridgeport  and  to  the  Fairfield  (Conn.) 
University.  These  scholarships  will  be 
known  as  the  Central  Labor  Union  Peter 
Benard  Memorial  Fund  and  The  Herald 
Peter  Benard  Memorial  Scholarship — a 
fitting  tribute  to  a  man  who  devoted  the 
greater  part  of  his  life  to  the  betterment 
of  his  fellowmen. 

Pete  is  survived  by  two  sons  and  three 
daughters. 

•  By  the  time  this  issue  goes  to  press 
Harvey  O'Laughlin,  past  president  of  St. 
Louis  Local  143,  will  have  become  a 
benedict.  He  was  married  on  June  10 
to  Miss  Helen  Brown,  who  is  prominent 
in  St.  Louis  business  circles.  Our  very 
best  wishes  go  to  the  happy  couple. 

•  Correction:  On  page  17  of  last 
month's  issue,  we  identified  the  man  on 
the  right-hand  side  of  the  picture  ap- 
pearing at  the  foot  of  column  one  as 
Tom  Fitzgerald,  when  it  should  have 
been  his  brother,  John,  president  of 
Cleveland  Local  160.  Tom,  who  is  also 
a  member  of  the  Cleveland  Local  and 
secretary  of  the  Local's  Bowling  League, 
did  not  appear  in  the  photo. 

•  Recent  out-of-town  visitors  to  the  off- 
ices   of    IP:     Leo    Moore,    member    of 


GALA  CELEBRATION    MARKS   35TH   ANNIVERSARY   FOR   LOCAL   323,   SPRINGFIELD,    ILL. 


A  dinner-dance  at  the  Terra  Plaza  commemorated  the  35th  anniversary  for  Local  323,  Spring- 
field, ill.  Delicious  food  plus  excellent  music  and  a  very  fine  floor  show  made  the  evening  an 
enjoyable  one.  The  showing  of  the  IA  Documentary  Film  was  a  highlight  of  the  party.  In 
addition  to  the  officers  and  members  of  the  Local,  present  at  the  affair  were  two  of  the  original 
charter  members — John    P.   Stutzman,   retired,   and   Walter   E.    Bryner,   of   the   Lincoln    Theatre. 


Hollywood  Local  165,  called  prior  to 
taking  off  for  a  three  months'  tour  of 
England  and  the  European  continent.  .  .  . 
A  visit  from  S.  N.  Agarwal,  head  of  Cine- 
fones,  one  of  India's  largest  dealers  in 
motion  picture  theatre  equipment,  was 
greatly  enjoyed  by  the  IP  staff,  who  were 
much  interested  in  Agarwal's  account  of 
present-day  customs  and  conditions  in 
India.  ...  J.  Gordon  Jackson,  member 
of  Vancouver  Local  348,  and  M.  Karp, 
member  of  Toronto  Local  173,  were 
among  our  Canadian  visitors.  .  .  .  From 
upstate  New  York  came  Richard  L. 
Kowell,  member  of  Syracuse  Local  376, 
and  Harry  H.  Lackey,  acting  business 
manager  for  Utica  Local  337. 

•  Nate  Golden,  member  of  Cleveland 
Local  160  and  chief  of  the  Motion  Pic- 
ture Division  of  the  U.  S.  Department 
of  Commerce,  left  for  Europe  early  this 
month  as  a  member  of  the  U.  S.  delega- 
tion at  Annecy,  France,  to  take  part  in 
the  discussions  relating  to  the  reciprocal 


CALIFORNIA    DISTRICT   NO.  2   DELEGATES   ENTERTAINED   BY   BAKERSFIELD   LOCAL   215 


Attending  the  recent  meeting  of  California  District  No.  2  were  representatives  from  Los  Angeles 
L.  150;  Hollywood  L.  165;  Bakersfield  L.  215;  San  Diego  L.  297;  Santa  Barbara  L.  442;  Santa 
Ana  L.  504;  Long  Beach  L.  521;  San  Bernardino  L.  577;  El  Centro  L.  656;  Hollywood  L.  659 
(cameramen);  Hollywood  L.  683  (laboratory  technicians);  Hollywood  L.  705  (costumers);  Holly- 
wood L.  706  (makeup  artists);  Ventura  Co.  L,  709;  Hollywood  L.  727  (utility  workers);  and  Los 
Angeles  L.  776,   (film  editors). 

Among  those  shown  in  the  group  above  are  Carl  Cooper,  IA  7th  vice-president;  Roy  Brewer, 
IA  West  Coast  representative;  Charlie  Vencill,  George  Schaffer,  Alonzo   Bennett,   Herb   Aller, 
Walter   McCormick,   James    Eddy,   Louis   Wutke,   John    Lehners,   and    Billy   Wise. 


NTERNATIONAL  PROJECTIONIST     •     June  1949 


trade  agreements  involving  motion  pic- 
tures and  equipment.  He  will  act  as 
consultant  and  advisor  to  the  negotiat- 
ing committee  on  problems  pertaining  to 
the  film  industry. 

At  the  conclusion  of  the  conference, 
Nate  and  Mrs.  Golden,  who  accompanied 
him  on  the  trip,  plan  to  visit  Germany, 
France,  Italy,  etc.,  for  the  purpose  of 
investigating  conditions  in  important 
European  motion  picture  centers. 

•  We  are  very  sorry  to  learn  of  the 
serious  illness  of  G.  (Newt)  Wallis, 
former  president  of  Local  105,  London, 
Ont.,  Canada.  Having  undergone  several 
operations  during  the  past  year,  Newt 
seemed  to  be  well  on  the  road  to  re- 
covery when  he  suffered  a  relapse. 

•  Prominent  in  Masonic  circles,  Orville 
Langheinrich,  member  of  Milwaukee 
Local  164,  had  a  public  installation  re- 
cently when  he  was  made  the  Eminent 
Commander  of  Henry  L.  Palmer  Com- 
mandery  No.  42,  Knights  Templar.  The 
entire  Local  membership  was  invited  to 
witness  the  ceremony. 

•  Charlie  Vencill,  secretary-treasurer  of 
Los  Angeles  Local  150,  has  requested 
this  department  to  inform  IP  readers 
who  are  contemplating  a  trip  to  the  West 
Coast  that  prevailing  conditions  in  Los 
Angeles  and  the  vicinity  do  not  allow 
for  the  employment  of  out-of-town  pro- 
jectionists. There  is  hardly  sufficient  work 
available  for  the  members  of  Local  150, 
and  the  chances  of  any  outsider  getting 
a  job  out  there  are  pretty  slim,  reports 
Vencill. 

•  Acting  as  business  manager  for  two 
Vancouver,  B.  C.  IA  Local  Unions — Pro- 
jectionists' Local  348  and  T-B  Local  72 
(cashiers,  ushers,  etc.) — proved  too  great 
a  strain  for  Bob  Foster  who  resigned  as 
business    manager    of    the    projectionist 

(Continued  on  page  26 


19 


Polarity  is  Strictly  Relative 


MAGNETISM  and  electricity  are  so 
related  that  it  is  rarely  possible 
to  discuss  one  without  some  refer- 
ence to  the  other.  Polarity  occurs  in 
each  subject:  but  whereas  N  and  S  poles 
are  the  terms  used  in  magnetism  to  show 
where  points  of  free  polarity  exist,  plus 
and  minus  signs  are  used  in  electricity 
to  indicate  points  of  reference  in  con- 
nection with  current  movement. 

In  algebra,  +  and  —  signs  are  used 
in  combination  as  additive  and  subtrac- 
tive  quantities,  but  they  must  be  used  in 
a  correct  sense.  For  instance,  the  ex- 
pression —  5  oranges  +  7  oranges  would 
be  quite  sensible,  since  the  actual  mean- 
ing would  be  +  2  oranges.  An  expres- 
sion such  as  ■ — 5  oranges  +  7  bananas 
would,  however,  remain  as  such,  for  one 
cannot  take  away  oranges  from  bananas. 

Similarly,  in  all  circumstances  where 
positive  ( + )  and  negative  ( — ) ,  or  N 
and  S  polarity  signs,  exist,  it  is  necessary 
to  indicate  some  reference  point — that 
is,  if  the  information  is  to  be  intelligible. 
A  few  observations  relative  to  this  topic 
will  undoubtedly  be  of  interest. 

For  the  sake  of  convenience  (if  nothing 
else)  it  is  usually  accepted  that  where 
an  air-gap  exists  in  a  magnetic  circuit, 
the  "lines  of  force"  leave  the  N  pole  and, 
after  passing  through  air,  reenter  the  S 
pole:  thus  the  lines  are  given  some  im- 
aginary direction. 

A  perfect  magnet — i.e.,  one  which  has 
no  losses  and  no  appreciable  external 
field — may  consist  of  a  complete  ring  of 
hard  magnetised  steel  (Fig.  1).  Accord- 
ing to  the  molecular  theory  of  magnet- 
ism, the  myriads  of  tiny  magnets  are 
arranged  end  to  end  and  in  perfect 
sequence,  and  since  there  is  no  break  in 
the    metal — no    air-gap — these    particles 


By  A.    BUCKLEY 

form  a  closed  ring  and  the  external  field 
of  influence  is  almost  non-existent. 

If  a  saw-cut  be  made  in  such  a  ring, 
at  any  point,  an  air-gap  will  exist  and 
a  free  intense  magnetic  field  will  be 
created  at  that  position.  Since  the  per- 
meability of  air  is  lower  than  that  of 
steel,  the  field  will  occupy  more  space 
that  it  did  when  only  steel  was  present 
(Fig.  2) .  Moreover,  the  ends  of  the  ring 
will  exhibit  "free"  polarity:  one  will  be 
North,  or  N,  and  the  other  South,  or  S. 
If  further  saw-cuts  be  made  at  any  points 
on  the  ring,  "free"  polarity  will  exist  at 
each  and  every  one. 

Obviously,  this  could  go  on  forever,  or 
nearly  so.  The  dominating  fact  in  these 
experiments  is  that  every  small  magnet 
has  two  points  of  reference — the  North 
and  the  South  poles. 

If  six  small  bar  magnets  be  positioned 
as  shown  in  Fig.  3,  the  magnetic  fields 
will  be  complex  and  every  magnet  will 
exhibit  "free"  polarity.  But  if,  as  shown 
in  Fig.  4,  the  magnets  are  placed  end 
to  end,  then,  apart  from  the  extreme 
points  of  assembly,  no  "free"  polarity 
will  exist. 

To  prove  that  points  of  polarity  are 
merely  relative,  refer  to  Fig.  1  where, 
assuming  the  direction  of  the  magnetic 
field  to  be  as  shown,  position  C  is  South 
relative  to  position  B  and  also  to  point 
D.  Positive  B  is  North  relative  to  C,  but 
South  is  relative  to  position  D.  The  same 
thing  happens  in  any  closed  magnetic 
ring,  for  from  any  point  of  reference  on 
the  magnet,  relative  positions  may  be 
either  North  or  South — according  to  the 
direction. 

Let   us   consider   an   interesting   point 


C     B     D 

FIGURE  1 


FIGURE  2 


which  has  an  exact  counterpart  in  elec- 
trical circuitry.  Referring  again  to  Fig. 
1,  where  point  A  at  the  top  and  point  B 
at  the  bottom  are  the  two  positions  under 
discussion.  Assuming  that  the  direction 
of  the  internal  field  is  as  shown,  then 
position  B  will  have  North  polarity  and 
A  South— if  the  left  side  of  the  ring  be 
under  consideration.  But  if  we  consider 
the  right  side  of  the  ring,  position  B  will 
be  South  relative  to  A. 

Graphical  Distribution 

In  a  simple  bar  magnet  the  intensity 
and  distribution  of  the  field  can  be 
shown  graphically,  as  in  Fig.  5.    It  will 


lOME 

slhin    silIJN    s:u;n    s 

FIGURE  3 

In      1 

1        1       1       1      sl 

FIGURE  4 

be  noted  that  the  center  of  the  bar  shows 
no  "free"  polarity.  If  the  magnet  be 
cut  in  half — exactly  in  the  same  way 
that  the  initial  ring  was  cut — then  "free" 


FIGURE  5 


N 


H 


FIGURE  6 

polarity  will  be  present.  Therefore,  free 
polarity  occurs  only  where  an  air-gap 
exists. 

When  a  bar  magnet  is  magnetized  in 
such  a  way  that  the  ends  are  of  similar 
polarity  and  the  center  point  is  of  an 
opposite  sign,  the  magnet  is  said  to 
possess  "consequent  poles."  Fig.  6  shows 
such  a  magnet.  In  any  case  of  this  type, 
two  separate  fields  will  exist,  for  the 
lines  of  force  leaving  the  North  pole 
must  complete  their  paths  through  air 
to  reenter  the  South  poles.  If  such  a 
magnet  be  cut  at  points  a  and  e,  "free" 
polarity  will  exist  at  these  points,  but 
the  center  section  will  still  possess  con- 
sequent poles.  Supposing  the  magnet 
to  be  cut  exactly  in  the  center,  then  the 
two  remaining  sections  will  be  ordinary 
bar  magnets  with  their  North  poles  op- 
posite each  other. 

Having  discussed  some  points  in  con- 


20 


INTERNATIONAL  PROJECTIONIST 


June  1949 


nection  with  magnetic  properties  and 
effects,  let  us  examine  several  conditions 
relative  to  electrical  circuits. 

A  simple  circuit  consists  of  a   closed 
loop  of  wire  which  can  be  represented 


AAAAA 


FIGURE  7 

by  Fig.  1.  Its  resemblance  to  the  per- 
fect magnet  will  be  at  once  apparent. 
In  such  a  loop  of  wire  any  current  created 
will  have  the  same  value  at  every  point, 
and  the  voltage  difference  between  any 
two  points  of  similar  measurement  will 
be  the  same. 

Taking  an  experimental  case  (exactly 
as  in  the  magnetic  example)  and  assum- 
ing current  direction  to  be  as  shown, 
point  C  will  be  negative  to  points  B  and 
D.  Point  D  will  be  positive  to  points  C 
and  B;  while  point  B  will  be  positive  to 
C  and  negative  to  D. 

Bearing  these  points  in  mind,  it  will 
be    seen  that  the   terms   "positive"   and 


FIGURE  8 

'"negative"  have  no  real  meaning  unless 
some  point  of  reference  is  indicated,  for 
any  point  can  be  either  negative  or  posi- 
tive. 

Let  us  use  a  somewhat  unusual  slant, 
having  a  resemblance  to  an  earber  mag- 
netic example.  Fig.  1  is  now  assumed  to 
be  a  closed  loop  with  points  A  and  B 
equidistant  from  each  other  in  both  di- 
rections. Neglecting  ohmic  resistance 
and  voltage  drop,  but  taking  current 
direction  as  shown,  if  we  consider  the 
left  side  of  the  loop,  point  B  will  be 
positive  to  point  A.  But  if  we  consider 
the  right  side  of  the  loop,  point  B  will 
now  be  negative  to  point  A. 

Reference  Point  Essential 

In  a  simple  cell  the  terminals  are 
marked  -f-  and  — .  The  +  terminal  is 
positive  and  current  is  assumed  to  enter 
the  cell  at  that  point.  Terminal  —  is 
negative    and    there    the    current    leaves 


the  cell.  Inside  the  cell,  however,  the 
terms  are  reversed,  as  shown  in  Fig.  7. 
It  must  be  remembered  that  the  same 
number  of  mobile  electrons  exists  in  all 
parts  of  a  closed  circuit,  and  that  whether 
a  simple  cell  or  dynamo  is  considered,  it 
merely  constitutes  an  electron  pump. 
Therefore,  the  terms  "plus"  and  "minus" 
are  really  meaningless  unless  some  point 
of  reference  is  mentioned. 

The  similarity  between  electrical  and 
magnetic  circumstances  is  shown  in  Fig. 
8.  At  point  a  the  position  is  positive  to 
points  b  and  c.  Similarly,  the  position 
a  on  the  magnet  is  North  to  positions  e 
and  /  .  Point  b  on  the  electrical  circuit 
is  +  to  point  c,  but  —  to  point  a.  Also, 
point  e  on  the  magnet  is  N  to  position 
f  but  S  to  point  d.  Therefore,  a  closed 
magnetic  ring — or  a  bar  magnet — has  a 
similar  counterpart  in  an  electrical  cir- 
cuit. 

In  ampHfier  work  the  point  of  refer- 
ence is  usually  the  chassis,  which  is,  in 
many  cases,  at  earth  potential.  Thus,  all 
voltages  existing  on  the  tube  elements, 
or  at  any  position  in  the  circuit,  are 
measured  from  this  reference  point. 
Anodes,  screens  and  cathodes  are  posi- 
tive with  respect  to  the  chassis,  while 
grids  are  often  negative  when  using  di- 
rectly-heated tube  filaments. 

Stream  of  Electrons 

A  mecury-arc  rectifier  is  a  fascinating 
instrument  and  lends  itself  well  to  the 
explanation  of  relative  plus  and  minus 
signs.  In  connection  with  this  device,  a 
very  able  projectionist  of  many  years 
standing  once  asked  the  writer  from 
whence  the  negative  point  of  the  circuit 
really  commenced.  Being  a  spot  ques- 
tion, it  made  the  writer  think  very 
quickly,  and  of  course  it  had  to  be  ex- 
plained that  the  negative  point,  or  the 
positive  one  too,  coud  be  anywhere  one 
wished. 

Figure  9  shows  the  fundamental  cir- 


cuit of  the  mercury-arc  rectifier.  The 
motion  of  electrons  is  from  the  mercury 
pool  to  whichever  anode  is  positive  at 
any  instant,  through  the  transformer 
windings  and  load  and  via  the  smooth- 


FIGURE  9 

ing  choke  back  to  the  mercury  pool.  In- 
side the  glass  bulb  the  cathode  is  the 
mercury  pool  which  emits  electrons  to 
the  anodes  in  turn:  these  are  positive 
when  conducting.  Outside  the  tube  the 
mercury  pool  is  the  positive  terminal  of 
the  outfit  and  the  connections  to  the 
center  tap  on  the  transformer  are  nega- 
tive. Thus,  we  give  further  proof  that 
signs  are  merely  relative. 

That's  the  important  thing  to  remem- 
ber: of,  by  and  in  themselves  signs  and 
symbols  are  almost  wholly  unimportant: 
they  must  be  interpreted  in  terms  of 
their  relation  to  other  signs  and  symbols. 


Peerless  Carbon  Dispenser 

The  peerless  Hy-Candescent  carbon 
disperser  provides  a  dry,  practical  and 
really  convenient  storage  cabinet  for  pro- 
jector arc  carbons.     It  attaches  directly 


to  the  under  side  of  the  base  plate  of 
the  Hy-Candescent  lamphouse,  with  very 
little  effort.  Each  carbon  compartment 
accommodates  one  full  package  (50 
pieces)  of  carbons.  Loading  is  easily 
done,  and  the  bottom  of  the  compart- 
ment is  so  designed  that  one  positive  and 
one  negative  carbon  is  served  at  a  time. 

One  end  of  the  dispenser  is  provided 
with  a  metal  fastener  to  which  may  be 
attached  a  hand  wiper  or  a  towel.  This 
dispenser  may  be  attached  to  all  Hy- 
Candescent  lamphouses  that  are  installed 
on  any  type  of  Simplex  pedestal. 


Peerless   Hy-Candescent  carbon   dispenser. 


New  Moriograph  In-Car  Speaker 

A  new  extremely  lightweight  in-car 
speaker,  featuring  great  strength,  attractive 
appearance,  improved  sound,  long  life  and 
low  maintenance  cost,  is  announced  by  Mo- 
tiograph.     The    round    housing    is    in    two 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


21 


pieces  of  moulded  plastic  with  a  flexural 
strength  of  10,000  pounds  and  a  tensile 
strength  of  9000  pounds  per  square  inch, 
permitting  unusually  rough  handling.  The 
housing  encloses  a  large  five-inch  weather- 
proofed  speaker  unit. 

The  speaker  housing  reportedly  will  with- 
stand 100%  humidity  and  200-degree  dry 
heat  tests,  the  equivalent  of  three  years'  out- 
door exposure,  without  warping,  chipping, 
cracking  or  marring  the  finish.  The  housing 
is  quickly  disassembled  by  the  simple  re- 
moval of  two  special  patented  screws. 

As  an  integral  part  of  the  shaft  of  the 
constant  impedance  volume  control,  the  vol- 
ume control  knob  cannot  drop  off  and  be 
lost.  This  knob,  as  well  as  the  concession 
signal  switch,  are  so  inset  in  the  side  of  the 
housing  as  to  prevent  damage  should  the 
speaker   be    dropped.    The    constant   imped- 


ance volume  control  permits  precise  adjust- 
ment of  sound  volume. 


Cautions  on  Tv  Surveys 

Interpreters  of  Tv  research  findings 
should  be  sensible  and  cautious  about 
swallowing — hook,  line  and  sinker — the 
results  of  surveys  made  of  that  medium 
thus  far,  Sidney  Roslow,  director  of 
The  Pulse,  told  the  American  Marketing 
Association  recently.  Pointing  out  that 
unwarranted  generalizations  have  been 
frequently  made,  Roslow  added: 

"The  questions  dealing  with  Tv  effects 
have  usually  come  in  the  course  of 
interviews  dealing  exhaustively  with  Tv. 
The  phrasing  of  the  question  has  been 
such  as  'Since  having  a  Tv  set  do  you 


ANSWER 
TO  YOUR 
TECHNICAL 
PROBLEMS . . . 


The  Altec 
Service  Man  and 
the  organization 
behind  him 


l6l  Sixth  Avenue, 
New  York  13,  N.  Y. 

PROTECTING  THE  THEATRE—FIRST  PLACE  IN  ENTERTAINMENT 


Manufactured  by 

HEYER-SHULTZ,  Inc. 


MONTCLAIR,  N.  J. 


ALL   METAL 

BM(Suto)B§ 

GUARANTEED  5  YEARS 


go  to  the  movies  more  often,  less  often, 
or  about  the  same?'  What  answer  could 
one  expect? 

"We  have  had  the  Tv  set  owner  say 
to  us  that  it's  not  Tv  that  keeps  him 
away  from  the  movies  but  rather  is  it 
the  poor  pictures  being  shown  at  the 
movies.  So  I  find  something  on  my  Tv 
set." 


Distributed  Exclusively  by 


Optical  Bulletin  by  U.  S.  Agency 

Optical  glass,  an  indispensable  raw  ma- 
terial for  precision  optical  instruments,  has 
been  developed  and  manufactured  by  the 
National  Bureau  of  Standards  since  World 
War  I.  Recently  the  Bureau  published  a 
description  of  the  procedures  it  uses  for  the 
production  of  optical  glass  in  its  experi- 
mental glass  plant.  This  publication,  "Opti- 
cal Glass  at  the  National  Bureau  of  Stand- 
ards," is  available  from  the  U.  S.  Govern- 
ment Printing  Office. 

Included  in  the  booklet  are  compositions, 
melting,  molding  procedures,  and  annealing 
schedules  for  many  types  of  optical  glass. 
Sections  are  devoted  to  such  topics  as  proper- 
ties of  optical  glass,  melting  pots,  batch 
materials,  the  melting  process,  preparing 
rough  glass  for  molding,  molding,  inspection 
of  molds,  and  annealing. 

Although  details  of  production  with  which 
an  experienced  glass  manufacturer  is 
familiar  have  been  largely  omitted,  sufficient 
information  is  given  to  enable  one  experi- 
enced in  the  trade  to  enter  the  optical  glass 
field. 

NBS  Circular  469,  Optical  Glass  at  the 
National  Bureau  of  Standards,  14  double- 
column  pages,  12  figures,  five  tables,  obtain- 
able from  the  Superintendent  of  Documents, 
U.  S.  Government  Printing  Office,  Washing- 
ton 25,  D.  C,  15c  a  copy.  Remittances 
from  foreign  countries  must  be  made  in 
U.  S.  exchange  and  must  include  an  addi- 
tional 1/3  of  the  publication  price  to  cover 
mailing  costs. 


BOOK     REVIEW 

The  Motion  Picture  Theatre — -Plan- 
ning and  Upkeep.  A  compendium  of  papers 
presented  at  the  SMPE  Theatre  Engineering; 
Conference.  428  pages,  profusely  illustrated, 
buckram.  $5.  SMPE,  342  Madison  Ave., 
N.  Y.  City. 

The  first  comprehensive  theatre  engineer- 
ing handbook,  detailing  the  physical  require- 
ments of  the  motion  picture  theatre  from 
the  blueprint  to  curtain  time  and  beyond, 
has  just  been  published  by  the  SMPE. 

This  generously  illustrated,  428-page  vol- 
ume, entitled  "The  Motion  Picture  Theatre 
— Planning  and  Upkeep,"  presents  in  non- 
technical language  a  wealth  of  data  on 
numerous  phases  of  theatre  design,  construc- 
tion modernization,  and  maintenance  under 
eight  major  headings:  Physical  Construc- 
tion, Auditorium  Design,  Ventilating  and 
Air  Conditioning,  Acoustics,  Lighting,  Floor 
Coverings,  Promotional  Display,  and  Tele- 
vision. 

The  book,  priced  at  $5,  is  now  available 
through  the  SMPE  offices,  342  Madison 
Avenue,  N.  Y.  City. 


22 


INTERNATIONAL  PROJECTIONIST 


June  1949 


Harry   Schiffman,   Student   of    Labor   Relations 


NOT  a  little  of  the  credit  for  the  re- 
cent successful  conclusion  Si  nego- 
tiations which  awarded  jurisdiction  over 
i  all  mechanical  and  machine  shop  work 
in  10  major  Hollywood  studios  to  the 
IA  is  being  deposited  in  the  lap  of  Harry 
Shiftman,  business  manager  for  IA  Cine- 
technicians  Local  789.  Members  of  789 
are  precision  machinists  and  toolmakers 
whose  function  is  to  keep  precision  equip- 
ment in  the  studios  in  top  operating  con- 
dition. 

Harry  Shiftman  is  interesting  to  IP 
readers  not  only  because  he  is  a  brother 
craftsman  but  also  because  he  always 
kept  his  chin  up  and  eyes  and  ears  open 
to  obtain  the  basic  facts  anent  smart 
labor  relations.  So  good  is  Harry  in  this 
field  that  his  projection  work  has  been 
on  the  strictly  limited  level. 

Migrating  from  Cleveland  to  Holly- 
wood in  1928,  Harry  found  the  projec- 
tion employment  situation  in  the  studios 
a  bit  on  the  rugged  side.  Necessity  dic- 
tated that  he  shift  from  one  classification 
to  another   on  the  various   lots,   and  in 


Harry 

Shiftman, 

business 

manager  for 

IA  Cinerech- 

nicians 

Local  789. 

• 


this  fashion  he  was  able  to  form  a  com- 
prehensive picture  of  the  Hollywood  la- 
bor situation  that  was  later  to  stand  both 
himself  and  the  IA  in  very  good  stead 
indeed. 

In  1936  the  IA  obtained  their  first  in- 
clusive closed-shop  contract  in  the  stu- 
dios, and  Harry  got  back  to  his  first  love 
— projection.  He  was  instrumental  in 
obtaining  the  separate  charter  for  Local 
165,  studio  projectionists,  of  which  he 
still  is  a  member.  In  fact,  the  first  name 
on  that  charter  is  Harry  Shiffman. 

Bang-up  Job  on  Machinists 

During  all  the  turmoil  engendered  in 
the  Hollywood  studios  in  1945  by  Sor- 
rell's  anti-IA  Conference  of  Studio 
Unions,  Shiffman  was  plugging  away  at 
the  assignment  to  bring  all  the  master 
machinists  under  the  IA  banner.  That 
Harry  did  a  masterful  job  is  evidenced 
by  the  contract  recently  signed  with  the 
IA,  no  less  than  by  the  fact  that  Harry 
was  practically  stolen  away  from  his 
projection  work  to  become  business  man- 
ager for  Local  789. 

In  Harry  s  job  there  isn't  any  too  much 
time  for  hobbying  around,  but  there  is 


one  Shiffman  hobby  that  gets  attention — 
steering  young  Gary  Shiftman's  career 
as  quarterback  for  Hamilton  High 
School.  Gary,  now  16,  is  merely  follow- 
ing in  his  father's  footsteps,  for  Harry 
did  quite  a  bit  of  pigskin-toting  back  in 
his  Ohio  days. 

Harry  Shiffman  is  much  more  than  a 
union  member  and  leader;  he  is  always 
digging  to  find  out  what  makes  unions 
tick  and  particularly  what  their  status 
is  with  respect  to  their  employers.  No 
degree  in  labor  relations  from  a  univer- 


sity has  Harry,  but  his  practical  store  of 
such  knowledge  places  him  away  out 
front  of  many  a  product  of  the  ivied 
walls. 


Silver  Vital  in  Photography 

Eighteen  tons  of  silver  are  used  annually 
in  putting  pictures  in  newspapers  and  in 
illustrating  books  and  magazines.  That's  as 
much  of  the  metal  as  goes  into  the  minting 
of  more  than  5  million  dimes.  But  for  print 
shop  use  it  is  spread  mighty  thin  and  must 
be  more  than  "mint  pure." 

Ancient  alchemists  helped  put  pictures  in 
your  newspapers.  They  tried  to  turn  silver 
into  gold.    In  the  course  of  failing,  they  dis- 


IMPART 


► 


TO  YOUR 


PRESENTATIONS 


Produces  a  sharp,  snow-white,  uniformly       makes  possible  a  high  intensity  arc  spot- 
illuminated    spot    far   surpassing    in    bril-       light   without   the    use   of   heavy   rotating 
liancy    any    incandescent   or   vertical    arc       equipment, 
spotlight  ...  a  light  such  as  is  obtainable 

only  with  high  intensity  arcs.                                   Automatic   arc   control    maintains   con- 
stant  arc   gap   and    a   steady    light,   free 

Easily  operated.                                                  *rom    mss   or   flicker.   A   trim    of   carbons 

burns  one  hour  and  20  minutes  at  21  volts 

Employs  a   silvered   glass   reflector  and       ond  45  amperes, 
two-element    variable    focal    length    lens            Horizontal    masking    control.     Can    be 
y         '                                                                     angled   at  45   degrees   in   each   direction. 

_               .     ,.                    ,                  ,,-         Color  boomerang  contains  six  slides  and 

Draws  only  10  amperes  from  any  110-       u|travio|et  fi|ter  ho|der. 
volt  A.C.  convenience  outlet.     Adjustable, 

self-regulating  transformer  which  is  an  in-           Mounted   on    casters.     Easily   disassem- 
tegral  part  of  the  base  for  the  first  time       bled  for  shipping. 

Use  coupon  to  obtain  literature,  prices  and  name 
of    nearest    independent    theatre    supply    dealer. 

THE 

STRONG 

ELECTRIC  CORP. 

Please  send  free  literature,  prices  and  name  of  the 
nearest  dealer  in  Strong  Spotlights. 

NAME                                                                                    

■    14  CITY   PARK  AVE.   D 
|      TOLEDO  2,  OHIO      | 

STREET                                                                        

INTERNATIONAL  PROJECTIONIST 


June  1949 


23 


covered  that  silver  nitrate  is  sensitive  to 
light.  That  Dark  Ages  discovery  slumbered 
for  centuries,  little  noted,  until  it  finally 
became  the  basic  chemical  principle  upon 
which  photography  is  built. 

Silver  Particles  on  the  Job  4  Times 

As  a  result,  silver,  as  particles  suspended 
in  gelatin  one-thousandth  inch  thick,  is  on 
the  job  four  times  in  the  course  of  helping 
to    illustrate    a    newspaper.      It    records    an 


image  on  a  negative  film  when  a  camera 
shutter  clicks.  It  transfers  that  image  as  a 
positive  onto  paper — slick  prints  for  pub- 
lishing use.  It  records  again  on  film  in  the 
photo-engraving  shop,  and  finally  on  the  cop- 
per plate  which  becomes  a  "half-tone  cut" 
—ready  for  printers'  ink. 

Nth  degree  purity  is  a  must;  but  even  if 
a  theoretical  100%  purity  could  be  attained, 
some  silver,  from  certain  mining  areas, 
would  not  do  because  through  all  refining 
processes  it  remains  faintly  radioactive. 
Press  photographers  and  photoengravers  can- 
not use  even  the  tiniest  trace  of  atomic 
energy. 

RCA  '400  Junior7  Single-Case 
16-mm  Soundfilm  Projector 

A  new  single-case  addition  to  the 
"400"  series  of  RCA  16-mm  sound  mo- 
tion picture  projectors,  known  as  the 
"400  Junior,"  will  be  available  in  June 
at  a  suggested  retail  price  of  $442.50. 
Compact  design  was  achieved  through 
an  ingenious  rearrangement  of  the  8-inch 
speaker  and  its  incorporation  in  the  lid 
of  the  case,  which  doubles  as  the  speaker 
baffle.  The  speaker  may  be  placed  adja- 
cent to  the  projector,  or  it  can  be  placed 
next  to  the  screen  through  the  use  of  a 
50-foot  cable.  The  lid  provides  adequate 
baffle  for  full  tonal  range. 

Many  Operational  Features 

A  unique  feature  of  the  "400  Junior" 
is  the  use  of  high-speed  gears  made  of 
nylon,  which  extensive  laboratory  tests 
have  shown  to  be  quieter  in  operation 
and  to  give  longer  life  than  steel  or  fibre 
gears.  Auxiliary  equipment,  in  addition 
to  the  speaker,  includes  a  15-foot  power 
cord,  a  reel  accommodating  400  feet  of 
film,  a  50-foot  speaker  cable  with  plug, 
upper  and  lower  reel  arms,  an  extra  ex- 
citer lamp,  oilcan,  box  fuses,  lens  tissue, 
aperture  brush,  and  a  threading  diagram. 

Among  the  operational  features  is 
constant  silent  speeds.  Selective  speed 
change  is  accomplished  mechanically,  so 
that  there  is  no  change  in  blower  speed, 
making  for  unusually  cool  running.  A 
second  feature  is  "theatrical  type"  fram- 
ing, which  adjusts  the  cooling  at  either 


CLAYTON  BALL-BEARING 

EVEN  TENSION  TAKE-UPS 

For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reek. 
Silent  Chain  Drives 

THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reels. 

CLAYTON    PRODUCTS    CO. 

31-45  Tibbett  Avenue  New  York  63,  N.  Y. 


Closeup  of  the  RCA  '400'  Junior  16-mm  pro- 
jector, without  lid  which  serves  as  baffle  for 
8-inch  speaker. 

sound  or  position  of  the  film  in  the  gate 
without  moving  the  aperture  plate. 

Visual,  Sound  Projection  Data 

An  embossed  guide-line  for  easy 
threading  is  incorporated  in  the  pro- 
jector, together  with  a  wide-swing  film 
gate,  and  cushion-action  sprocket  shoes. 
Rewinding  of  film  is  automatic,  requir- 
ing no  changing  of  reels.  Even  tension 
takeup  is  maintained  regardless  of  the 
amount  of  film  on  the  reel.  The  power- 
ful 4-stage  amplifier  delivers  a  full  10- 
watt  output  with  less  than  5%  distortion 
throughout  the  16-mm  recording  range. 

Die-casting  of  the  main  frame,  back- 
plate,  and  lamphouse  permits  a  high 
degree  of  accuracy  in  assembly  and  close 
control  of  fabrication. 


LOU  P ADOLF— Manager,  Virginia 
Theatre,  Parkersburg,  W.  Va. — 
writes: 

"For  the  past  10  years  I 
have  been  using  RCA  Ser- 
vice. I  feel  it  is  one  of  the 
best  investments  I  have 
made  for  this  theatre." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


24 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


Wenzel  Sound  Systems  Available 

Wenzel  Projector  Co.  has  resumed  the 
manufacture  of  complete  sound  repro- 
ducing systems  which  had  been  discon- 
tinued through  the  war  years.  The  new 
line  provides  soundheads  for  all  types 
and  sizes  of  theatres. 

Complete  units  now  supplied  by  Wen- 
zel include  amplifiers,  speaker  systems, 
soundheads,  upper  and  lower  magazines, 
rear-shutter  projectors,  and  the  de-luxe 
WB-600  or  the  5-point  pedestals.  Full 
details  available  from  Wenzel  at  2505 
South  State  St.,  Chicago. 


Robust  Paramount  Earnings  in  1949 

Paramount  Pictures  earned  $24,357,102 
for  the  fiscal  year  ending  Jan.  1  last,  as  com- 
pared with  131,440,477  for  the  previous  year. 
While  the  Par  net  is  down  some  $7  millions 
from  the  preceding  year,  and  considerably 
below  the  record  1946  figure,  it  is  consider- 
ably higher  than  the  nets  earned  during  the 
war  years  and  before. 

Barney  Balaban,  Par  president,  reiterated 
his  previously  expressed  contention  that 
Tv  "may  turn  out  to  be  our  companion 
rather  than  our  antagonist."  An  aggregate 
amount  of  $1,253,235  was  paid  by  Par  and 
its  subsidiaries  to  officers  and  directors  dur- 
ing the  year.  Balaban  received  $156,000, 
plus  benefits  under  a  pension  trust  plan  of 
$37,687. 


Tv  'Freeze'  to  Last  Through  Summer 

The  present  "freeze"  on  Tv  will  last 
throughout  the  Summer,  FCC  Chairman 
Coy  announced.  He  estimated  that  with- 
in five  years  40  to  50%  of  American 
homes  would  have  Tv  sets,  with  from 
600  to  800  stations  on  the  air  with  the 
UHF  band  in  use. 


FP  Canadian  '48  Profits  Increase 

Famous  Players  Canadian  in  1948  showed 
a  net  profit  of  $3,286,264,  equal  to  $1.89  per 
common  share,  according  to  the  Paramount 
subsidiary's  annual  report.  Figures  com- 
pare with  $3,156,446  profits  in  1947,  equal 
to  $1.81  per  common  share. 

J.  J.  Fitzgibbons,  FPC  president,  said 
gross  boxoffice  receipts  were  up  last  year, 
but  net  operating1  income  was  trimmed  by 
higher  costs.  He  expects  a  good  year  in 
1949. 


Exposure  Frame  of  1/1500  Second 

The  distance  of  the  3-kilometer  speed 
course  (approx.  1%  miles)  laid  out  at 
Rodg-ers  Dry  Lake,  Muroc,  Calif.,  was  sur- 
veyed by  the  U.  S.  Coast  and  Geodetic  Sur- 
vey to  an  accuracy  of  one  part  in  600,000, 
each  end  of  the  course  being  indicated  by 
bench  marks  set  in  concrete.  Three  inches 
behind  these  bench  marks  are  concrete  bases, 
three  feet  high,  used  as  rigid  mounts  for 
high-speed  cameras. 

A  four-point  perpendicular  datum  plane  is 
formed  at  each  end  of  the  course  by  (1) 
the  center  of  the  camera  lens  (2)  the  bench 
marks  (3)  an  alignment  cable,  and  (4)  an 
alignment  stake.  The  high-speed  camera, 
which  winds  16-mm  film  at  the  rate  of  500 


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LENS  ELEMENTS 


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ARE  SNAPLITE  LENSES  SEALED? 

All  Snaplite  Series  II  and  Super-Snaplite  lenses  manu- 
factured since  January  1946  are  of  sealed  construc- 
tion to  prevent  entrance  of  moisture,  dust  or  oil. 

HOW  ARE  THEY  SEALED? 

This  is  accomplished  by  using  a  one-piece  lens  barrel 
made  from  a  solid  bar  with  no  threaded  joints.  The 
front  and  rear  lens  elements  are  sealed  by  means  of 
synthetic  rubber  gaskets. 

SHOULD  SEALED  LENSES  BE  TAKEN  APART? 

No!  Never  disassemble  a  Snaplite  Series  II  or  Super- 
Snaplite  lens.  If  any  indication  develops  that  the  lens 
needs  to  be  taken  apart,  it  should  be  returned  to  the 
factory  for  complete  examination. 

WHY  IS  ALUMINUM  USED  FOR  SNAPLITE 
LENS  MOUNTS? 

Because  of  its  light  weight,  high  strength  aluminum 
alloy  is  preferred  to  brass  for  lens  mounts,  especially 
if  it  is  protected  by  anodizing.  Gold  anodized  finish 
is  used  on  Super-Snaplites,  while  black  was  selected 
for  Series  I  and  Series  II  Snaplites. 

ARE  PLASTIC  MOUNTS  USED  IN 
SNAPLITE  LENSES? 

Definitely  not.  The  black  anodized  aluminum 
barrel  has  been  mistaken  for  plastic,  but  we 
do  not  consider  plastics  as  being  suitable 
materials  for  mounting  lenses  of  high  pre- 
cision. 

'You  Get  the  Most  Uniform  Light  with  Super-Snaplite" 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


© 

OKPOICjITIOR! 


INTERNATIONAL  PROJECTIONIST 


June  1949 


25 


pictures  per  second,  records  the  flight  of 
the  plane  some  800  feet  out  beyond  the 
camera  stations,  parallel  to  a  line  joining 
the  bench  marks. 

The   optics   of  the   camera   are   such   that 


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Complete    information    on 

Servicing  a  Theatre  Sound  System 

is    contained    in    the 

SOUND  TRACK  BOOK  OF  THE  THEATRE 

Price    $10.00 

The    Sound    Track 

1001    W.    Washington    Blvd.  Chicago   7,    III. 


the  actual  exposure  per  frame  of  motion  pic- 
tures is  1/1500  second,  corresponding  to  an 
airplane  movement  of  0.655  feet  traveling  at 
670  miles  per  hour.  By  making  certain 
corrections,  it  is  said  to  be  possible  to  de- 
termine the  position  in  space  of  the  air- 
craft at  700  miles  per  hour  to  an  accuracy  of 
±0.25  feet  per  pass.  The  electronic  timing 
equipment  is  very  complicated.  The  second- 
ary timing  clock  is  recorded  on  each  exposed 
frame  of  the  motion  picture. 


DeVry  1949  In-Car  Speaker 

Many  of  the  new  weather-proofed  1949 
model  DeVry  In-Car  speakers  are  already 
installed  in  drive-in  theatres  throughout  the 
country.  Features  include  all  the  latest 
improvements  in  materials  and  finishes  that 
have  proved  best  after  years  of  extensive 
tests  in  the  laboratory  and  in  the  fie'd.  The 
speakers  are  streamlined  for  lightness  in 
weight,  yet  are  fabricated  of  materials  that 
will   stand  up   under  constant  use. 

The  speaker  case  is  of  anodized  heavy 
gauge  aluminum  alloy.  The  aluminite  finish 
is  highly  resistant  to  corrosion,  chipping  and 
peeling1,  as  well  as  being  easier  to  see  in 
the  dark  by  the  drive-in  patron. 

G.  E.  speaker  units  featuring  aluminum 
voice  coil  mountings  are  incorporated.  These 
mountings  will  not  alter  their  shape  or  be 
affected  by  heat  and  moisture.  A  heavy 
Alnico  V  permanent  magnet  speaker  assures 
the  highest  efficiency.  Drain  holes  empty 
rain  water  or  condensation  from  inside  of 
case.  The  transformer  is  likewise  weather- 
proofed  for  continuous,  trouble-free  service. 


Westrex  100-Wart  Amplifier 

A  new  100-watt  Class  A  amplifier  built 
as  a  single  unit  has  been  designed  by 
Westrex  Corp.  It  marks  the  first  amplifier 
of  its  kind  available  for  theatre  use.  The 
Class  A  push-pull  power  stage  reduces  har- 
monic distortion  to  less  than  1%%  at  the 
full  rated  output.  Microswitches  automati- 
cally provide  full  protection  against  high- 
voltage    hazards. 

The  voltage  driver  unit  is  identical  to  that 
used  in  all  Westrex  high-powered  amplifiers 
and  may  be  completely  replaced,  in  the 
event  of  failure,  simply  by  the  use  of  a 
screwdriver.  Only  one  electrolytic  condenser 
is  used   in   amplification,  that  being  of  the 


Stan,  fienfrvumsutce  with  STAR  CORE 


STAR  CORE,  exclusive  feature  with  the 
Lorraine  Carbons  —  a  manufacturing 
process  that  increases  the  performance 
of  the  carbons. 

A  more  brilliant,  steadier,  more  con- 
sistent white  light— more  economically 
. . .  proven  facts  as  shown  by  tests 
made  under  actually  operating  ton-, 
ditions. 


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Improved  1949  model  of  DeVry  in-car  speaker 

plugvin  type  which  may  be  replaced  as 
readily  as  a  tube.  All  resistors,  except 
those  in  the  power  stages,  are  of  a  precision 
type  with  a  maximum  tolerance  of  1%. 


M.  W.  Paarman  has  been  appointed  sales 
manager  for  the  DeVry  35-mm  Theatre 
Equipment  Division.  A  veteran  of  more  than 
20  years  with  DeVry,  Paarman  recently 
headed  up  the  16-mm  section  for  the  com- 
pany. 

Paarman  succeeds  Ira  L.  Fleming,  who  is 
now  associated  with  the  Midwest  Theatre 
Supply  Co.,  Chicago,  handling  DeVry  thea- 
tre  projection   equipment   in   Illinois. 


IN  THE  SPOTLIGHT 

{Continued  from  page  19) 

Local  to  devote  his  entire  time  to  the 
B  Local.  Ted  Foley,  recorder  for  Local 
348,  was  elected  to  fill  the  post  vacated 
by  Foster,  and  Les  Walker,  former  execu- 
tive board  member,  was  elected  recorder. 
About  18  months  ago  the  IA  granted 
a  charter  to  T-B  Local  72  and  appointed 
Bob  Foster  to  organize  it.  The  Local 
now  has  a  membership  of  200,  Foster 
having  recently  successfully  concluded 
new  contracts  for  the  members  calling 
for  increased  wages.  Results  are  what 
count — and  the  records  show  that  Bob 
certainly  produced  them. 

•  On  behalf  of  the  AK  Club  we  extend 
a  welcome  hand  to  our  old  friend,  Con- 
rad Krieger,  secretary  of  Local  586, 
Grand  Island,  Nebr.,  who  recently  joined 
the  ever-growing  ranks  of  grandfathers. 
It  is  an  old  story  to  yours  truly — we  made 
the  grade  three  times  to  date. 

°  Several  years  ago  Harry  Barco,  busi- 
ness manager  for  St.  Louis  Local  143, 
had  the  foresight  to  sign  up  Station 
KSD-TV  and  placed  one  of  his  members 
on  the  job.  Evidently  the  top  brass  at 
KSD  are  pleased  with  the  deal,  for  now 
that  the  station  has  expanded  its  activi- 
ties, they  recently  signed  up  for  a  second 
Local  143  man.  Each  man  on  the  job 
receives  $100  for  a  40-hour  week. 

•  Boston     Local     182    has     long     been 


26 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


TORONTO  LOCAL  173  HONORS  BILL  COVERT 


William  P.  Covert  (left),  business  manager  of 
Toronto  Local  173  and  2nd  IA  vice-president, 
was  presented  with  a  traveling  bag  by  the 
members  of  the  Local  prior  to  his  departure  for 
Geneva,  Switzerland,  where  he  will  act  as  ad- 
visor to  the  Canadian  delegation  to  the  Inter- 
national Labor  Conference.  James  Sturgess 
president  of  173,  made  the  presentation. 

plagued  by  the  existence  of  a  dual  or- 
ganization known  as  the  Knights  of 
Labor,  which  operated  under  a  State 
charter  for  more  than  30  years.  A  series 
of  conferences  extending  over  a  three- 
year  period  between  the  officers  of  the 
IA  and  K.  of  L.  locals  led  to  the  dis- 
solution recently  of  the  latter  organiza- 
tion and,  at  a  special  meeting  held  on 
May  16  last,  Local  182  granted  full  mem- 
bership to  the  K.  of  L.  members  work- 
ing in  its  jurisdiction. 

Representing  Local  182  at  the  negotia- 
tions were  Joseph  Nuzzolo,  St.,  and 
Walter  F.  Diehl,  president  and  business 
manager,  respectively,  and  the  Local 
executive  board.  William  C.  Scanlan,  IA 
trustee,  obligated  the  former  K.  of  L. 
members. 

25  Years  Ago— June  1924 

•  William  F.  Canavan  re-elected  presi- 
dent at  the  27th  IA  Convention  held  in 
Cincinnati,    Ohio.    .    .    .    Fred    Dempsey, 

BOSTON  LOCAL  ELIMINATES  RUMP  UNION 


Officers  of  Boston  Local  182  and  of  the  Knights 
of  Labor  in  a  final  get-together  after  the 
latter  outfit  surrendered  its  charter  to  the  IA 
Local.  Shown  above,  left  to  right,  are  Joseph 
Nuzzolo,  Sr.,  president  of  Local  182;  Harry 
Martin,  business  agent,  and  Samuel  Garfinkle, 
president  of  the  now  defunct  K.  of  L.,  and 
Walter  F.  Diehl,  business  manager  of  Local  182. 


Bill  Covert,  Bill  Elliott,  H.  Guy  Culver 
and  Cleve  Beck,  re-elected  IA  vice- 
presidents.  Two  new  vice-presidents, 
George  E.  Browne  and  Thomas  Flahive, 
were  elected.  Flahive  resigned  shortly 
after  the  election  returns  came  in  and 
the  General  Executive  Board  unanimously 
elected  John  P.  Nick  to  fill  the  vacancy. 
.  .  .  Charles  H.  Bonn,  IA  president  in 
1901,  obligated  all  the  elected  officers. 
.  .  .  Injunctions  against  labor  an  import- 
ant factor  in  labor  controversies.  Kansas 
State  Federation  of  Labor  assisted 
Wichita  Locals  190  and  414  in  appealing 
injunctions  obtained  by  theatre  man- 
agers. .  .  .  Charters  were  granted  to  mo- 
tion picture  studio  workers  in  Los  An- 
geles and  Greater  New  York.  .  .  .  The 
per  diem  for  convention  delegates  boosted 
from  $8  to  $10  per  day. 


I  A     ELECTION 

LOCAL  NO.  4,  BROOKLYN,  N.  Y. 

Richard  F.  Walsh,  pres.;  John  Hinchie, 
vice-pres.;  Linford  Risley,  sec;  Theodore 
Samuelson,  treas.;  Thomas  Murtha,  bus. 
mgr.  Harry  Bennett,  Parker  Mann,  Fred 
Marshall,  Thomas  Murphy,  Jack  Patten, 
Walter  Will,  exec,  board;  Fred  Kraus,  Al- 
bert Linde,  Fred  Schonberg,  trustees; 
Charles  Cohen,  sgt.-at-arms. 


B.  B.  ANDERSON— Owner,  An- 
derson Theatre  Company,  Mullins, 
South  Carolina — declares: 

"We  use  RCA  Service  in  every 
Anderson  Theatre  and  have 
found  the  service  very  satis- 
factory." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


PROJECTIONISTS' 
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NATIONAL 

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DJrtu'cm  «!  No%f«t*l  *  Simple*  *  Vt*4w*f%h,ln< 


INTERNATIONAL  PROJECTIONIST 


June  1949 


27 


CARBON  COOLING  OF  HIGH-CURRENT  ARCS 


(Continued  }r 

cooling.  By  water-cooling,  however,  its 
consumption  is  reduced  by  as  much  as 
35%.  In  order  to  demonstrate  the  scat- 
tering of  the  measurements,  some  con- 
sumption-brightness measurements  for 
the  uncooled  arc  are  plotted  in  Fig.  10. 

Influence  on  Crater  Depth 

There  is  also  a  marked  influence  of 
water-cooling  on  the~ crater  depth  which, 
referred   to   arc   wattage    (Fig.    11),   or 


The 

answers  on   HOW  TO  DESIGN,  CONSTRUCT 

&    EQUIP    A    DRIVE-IN    THEATRE 

are  contained   in 

THE  SOW  TRACK  BOOK  OF  THE  THEATRE 

Price    $1  0.00 

The    Sound    Track 

1001 

W.    Washington    Blvd.            Chicago   7,    III. 

om  page  17) 
brightness  (Fig.  12),  becomes  shallower 
by  cooling  the  positive  carbon.  This 
effect,  although  in  Fig.  12  amounting  to 
only  approximately  14%  at  higher 
brightness,  is  of  technical  importance, 
because  too  deep  a  crater  is  not  well 
suited  for  illuminating  lenses  or  mirrors 
of  large  apertures. 

Measurements  carried  out  with  the 
air-cooled  head  (Fig.  3)  gave  results 
similar  to  those  just  described;  however, 
the  differences  in  the  properties  between 
the  air-cooled  and  the  uncooled  arc  are 
not  quite  so  large  as  those  between  the 
water-cooled  and  the  uncooled  arc. 

All  described  results,  attained  with 
the  carbon  No.  070  were  checked  with 
two  further  experimental  carbons,  Nos. 
081  and  088,  and  with  regular  12-mm 
searchlight  carbons.  While  the  absolute 
values  of  all  arc  properties  varied  be- 
cause   of    different   values    of    core    and 


HOWARD  R.  JOHNSON— Man- 
ager, Strand  Theatre,  Hamderi; 
Conn. — says: 

"The  Showman's  Number  One 
consideration  is  his  booth's  oper- 
ation. RCA  Service  is  100  per 
cent  insurance  against  break- 
down and  a  top  boost  to  highest 
efficiency  of  light  and  sound 
quality." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  New  Jersey. 


NET   ARC  WATTAGE   IN    KW. 


FIG.  11 — Comparison  of  crater  depth  of  cooled 
and  uncooled  arcs  for  equal  net  arc  wattages. 

though   more   pronounced   with   carbons 
specially  designed  for  this  purpose. 

Results,  Theoretical  Conclusions 

From  the  technical  point  of  view, 
water-cooling  of  both  carbons  has  the 
advantage  of  making  possible  the  appli- 
cation of  considerably  higher  brightness 


FIGURE  12 

Q. 

Comparison     of    crater    depth     of     S  t 
cooled  and  uncooled  arcs  for  equal      5 

o 

crater  brightness. 


— 4r$ 

sA  *y 

&/    I  &/ 


800  IOOO  1200  1400  ICOO 

CRATER     BRIGHTNESS     IN  CANDLES   /  MM* 


shell  diameters,  the  change  of  the  arc 
properties  as  a  consequence  of  cooling 
the  positive  carbon  was  similar  to  that 
for  the  carbon  No.  070.  The  effect  of 
carbon  cooling  on  the  high-current  car- 
bon arc  thus  seems  to  be  a  general  one, 


\  w 


Wenzel  Presents  . . .  SOUND  HEAD  WSH- 


7 


/ 


Send  for  complete  descriptive  circulars,  giving 
full  details  of  the  many  advantages  of  this 
new  WENZEL  product. 


WENZEL    PROJECTOR    CO. 


2505-19   S.   State   St. 
Chicago     16,     III. 


than  was  hitherto  possible  with  good 
steadiness  of  the  arc,  with  a  shallower 
crater  depth,  and  with  greatly  reduced 
carbon  consumption.  The  only  disadvan- 
tage is  that  the  required  current  is  con- 
siderably higher  than  without  cooling, 
while  the  decreased  arc  voltage  does  not 
form  a  compensating  technical  advan- 
tage. 

From  the  physical   point  of  view  we 
have  three  important  results: 

1.  The  reduced  net  arc  voltage  indi- 
cates a  decrease  of  the  anode  drop 
as  a  result  of  cooling  the  positive 
carbon. 

2.  No  arc  property  was  found  which 
was  not  changed  by  cooling  the  posi- 
tive carbon,  leading  to  the  conclu- 
sion that  a  cooled  and  an  uncooled 
carbon  behave  like  carbons  of  differ- 
ent composition  or  structure,  these 
internal  changes  being  caused  by 
the  different  temperatures  immedi- 
ately behind  their  burning  ends. 

3.  These   internal   changes   in   the   car- 


28 


INTERNATIONAL  PROJECTIONIST     •     June  1949 


bons  have  been  confirmed  by  X-ray 
diffraction  studies,  the  results  of 
which  will  be  described  in  detail  in 
a  future  publication. 

Mechanism  of  Cooling  Influence 

The  mechanism  of  the  cooling  influ- 
ence follows  from  these  results  in  con- 
nection with  earlier  investigations  of  the 
arc  mechanism  by  the  author,  and  can 
be  indicated  here  only  briefly. 

The  electrons,  accelerated  by  the 
anode-drop  potential,  transfer  an  energy 
of  6  to  7  kilowatts  to  each  sq.  centimeter 
of  the  crater  surface  which  serves  to 
vaporize  anode  material  and  heat  it  to  a 
temperature  of  about  6000  to  7000  de- 
grees Kelvin. 

The  illuminant  vapor  is  heated  fur- 
thermore by  collisions  with  electrons  in 
and  immediately  in  front  of  the  positive 
crater,  the  electrons  dissipating  there  an 
additional  amount  of  2  to  3  kilowatts. 
The  resulting  vapor  temperature  of  7000 
to  8000  degrees  Kelvin  is  responsible 
for  the  high  brightness  of  the  crater 
vapors. 

The  limit  of  load  which  a  positive 
carbon  can  stand,  and  which  determines 
the  maximum  brightness,  is  given  by  the 
transition  to  an  unsteady,  explosive  va- 
porization instead  of  the  desirable 
smooth  and  steady  evaporation.  This 
limit  depends  on  the  chemical  and  physi- 
cal structure  of  the  carbon. 

The  possibility  of  using  higher  current 
density  and  thus  attaining  higher  bright- 
ness by  cooling  the  positive  carbon 
seems  to  be  caused  by  two  effects :  First, 
we  have  a  reduction  of  the  anode  drop 
which  means  a  reduction  of  the  energy 
spent  for  vaporization  at  a  given  current. 
Second,  the  carbon,  being  kept  cool  up 
to  a  point  quite  near  to  the  crater,  keeps 
its  original  structure  unchanged  (com- 
pared with  the  highly  heated  uncooled 
carbon)  and  therefore  is  able  to  stand 
a  higher  load  before  beginning  to  evapo- 
rate unsteadily. 


Editor's  Note — Another  article  on  the  water- 
cooling  of  carbon  arcs,  by  National  Carbon 
technicians,  will  appear  in  an  early  issue,  prob- 
ably the  next. 

MATCHED'  PROJECTOR  OPTICS 

(Continued  from  page  12) 

rors),  a  spurious  and  misleading  system 
that  I  have  attacked  time  and  again. 

I  pointed  out1  why  F-numbers  should 
be  used  for  rating  projection  lenses,  and 
should  not  be  used  for  rating  condensing 
elements. 

1  "This  'Matching'  of  Projection  Optics,"  by  Robert 
A.    Mitchell;    IP    for    March,    1949,    p.    7. 


Your  Best  Buy  .  .  . 

U.  S.  SAVINGS  BONDS 


The  measurement  of  working  distance 
from  the  periphery  of  the  mirror  to  the 
film  plane  instead  of  from  the  center  of 
the  mirror  to  the  film  plane  is  an  interest- 
ing point  brought  out  by  Mr.  Cricks,  and 
one  which  I  had  carelessly  overlooked. 
I  believe  that  both  measurements  of  dis- 
tance are  useful,  but  they  should  be  given 
distinguishing  names  upon  which  all 
workers  in  the  art  agree. 

For  the  present  I  shall  use  the  mirror- 
center  to  film-plane  "working  distance" 
for  the  calculation  of  mirror  focal  char- 
acteristics, and  the  mirror-periphery  to 
film-plane  "working  distance"  for 
matched   optics  computations. 

Definition  of  Terms 

The  "experiment"  mentioned  by  Mr. 
Cricks  to  reveal  the  direction  of  the  rays 
which  illuminate  different  portions  of  the 
projector  aperture  are  entirely  in  line 
with  my  exposition  of  the  subject  in  the 
article  referred  to.1 

I  attributed  part  of  this  effect  to  spher- 
ical aberration  of  the  mirror.  I  neglected 
to  mention  that  the  remainder — the  great- 
est part — of  the  effect  is  due  to  the  fact 
that  the  rear  element  of  the  projection 
lens  lies  considerably  beyond  the  focal 
image  plane  of  the  mirror  (the  image  of 
the  arc)  which,  it  may  be  assumed,  coin- 
cides with  the  film  plane  at  the  aperture. 

It  is  impossible,  therefore,  for  the  pro- 
jection lens  to  "look"  through  the  aper- 
ture and  "see"  a  uniformly  illuminated 
mirror.  Hence  different  areas  of  the  lens 
"see"  different  areas  of  the  film  picture 
in  the  aperture  under  varying  degrees  of 
illumination.  All  this  is  in  complete 
agreement  with  Mr.  Cricks's  discussion. 

The  reference  by  Mr.  Cricks's  to  "or- 


thodox" optical  formulas  of  recent  ap- 
pearance in  the  American  trade  press 
naturally  turns  my  thoughts  to  the  "gen- 
eral formula"   for  matched  optics  which 


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29 


I  developed  for  the  convenience  of  read- 
ers of  IP  (it  appeared  in  two  forms  on 
page  9  of  IP  for  March,  1949). 

True  it  is  that  this  formula  does  not 
take  account  of  "eclipsing"  in  the  pro- 
jection lens — indeed,  that  would  require 
a  separate  formula  for  each  type  of  lens! 
However,  eclipsing  is  negligible  in  pres- 
ent-day lenses.  There  are  no  stops  in 
any  modern  American  projection  lens 
that  I  know  of;  and,  furthermore,  when 
an  American  manufacturer  rates  a  lens 
at  a  given  speed,  he  means  that  the  com- 
plete, assembled  lens  has  that  speed — 
not  just  the  back  element  alone. 

The  Vignetting  Effect 

The  vignetting  effect  arising  in  the 
projection  lens  is  therefore  ordinarily 
due  to  the  fact  that  the  lens  in  question 
simply  is  not  large  enough  to  match  the 
lamp  condensing  element.  My  general 
formula  enables  calculation  of  the  F- 
number  of  any  lens  matching  a  given 
lamp.  If  it  were  possible  to  use  a  lens 
having  the  exact  speed  given  by  the  gen- 
eral formula,  there  would  be  absolutely 
no  vignetting  caused  by  the  lens — any 
vignetting  present  would  be  due  to  a 
poorly  designed  lamp. 

In  many  cases  it  is  quite  possible  to 
use  lenses  sufficiently  large  to  reduce 
lens  vignetting  to  a  negligible  quantity, 
but  in  most  cases  perfect  matching  can- 
not be  attained  because  lenses  large 
enough  are  not  available.  Of  course,  I 
regret  exceedingly  that  "the  results  ob- 
tained from  these  formulas  indicate  the 
entire  impossibility  of  meeting  the  re- 
quirements"   (of   perfect   optical  match- 


Back 
Element 


Illustrating  the  points  made  in  accompanying  article  by  R.  A.  Mitchell. 


irig),  but  things  are  as  they  are,  no  more 
and  no  less,  and  the  general  formula 
conforms  to  unalterable  facts. 

Conception  of  F-N umbers  . 

It  interests  me  greatly  to  see  that  Mr. 
Cricks  attempts  to  traverse  the  ground 
which  already  bears  my  footprints;  viz., 
the  preliminary  determination  of  the  di- 
mensions of  the  cone  of  light  which  em- 
erges from  the  aperture.  But  his  analysis 
of  the  situation  is  erroneous  because  of 
his  refusal  to  reject  the  false  and  worth- 
less F-number  ratings  of  mirror  speeds. 
Although  his  formula 

B  +  f 
L  =  

f 

(in  which  L  is  back-element  diameter,  B 
the  distance  from  back  element  to  aper- 
ture, and  /  is  the  distance  from  "cross- 
over point"  to  aperture)   is  correct  as  it 


How  Many? 


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many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
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Use  coupon  below. 


INTERNATIONAL    PROJECTIONIST. 
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stands,  his  definition  of  F  is  incorrect. 

The  distance  of  the  crossover  point  of 
the  marginal  rays  behind  an  aperture  of 
1  inch  diagonal  is  not  given  by  the  F- 
number  of  the  mirror.  His  error  ap- 
proaches 0  as  the  spurious  mirror  F- 
number  approaches  0,  and  his  error  ap- 
proaches an  infinitely  great  number  when 
the  mirror  speed  approaches  infinity. 
For  the  average  projection  set-up  the 
error  is  in  the  neighborhood  of  10%. 

The  true  value  of  F  is  derived  as  fol- 
lows. (Refer  to  the  accompanying  dia- 
gram for  the  meaning  of  w  and  y.)  Be- 
cause w  =  /  +  y,  the  value  of  w  in  terms 
of  /  is  given  by  w  —  f  +  fr,  in  which  r 
is  the  ratio  of  y  to  /.  Solving  for  /  we 
obtain : 


f 


1  +  r 

which  is  the  desired  correct  solution  of 
the  distance  of  the  cross-over  point  from 
the  aperture. 

The  dispersion  of  light  by  silver  grains 
in  the  film  emulsion  and  the  suspected 
reduction  of  image  contrast  values  from 
this  cause  when  extremely  "fast"  lenses 
are  employed  is  an  interesting  topic. 
Such  an  effect  cannot  possibly  result 
when  Technicolor  film  is  projected,  how- 
ever, for  there  are  no  silver  grains  in  the 
dye  image. 

While  admitting  the  existence  of  dis- 
persion in  black-and-white  films,  the 
writer  is  not  convinced  that  the  effect 
would  ever  be  sufficiently  pronounced  to 
show  up  on  the  screen.  More  contrast  is 
lost  through  soiled  and  scratched  lenses 
and  port  glasses  and  by  stray  light  in 
the  auditorium  than  by  any  other  assign- 
able causes.  We  must  remember,  of 
course,  that  the  processers  of  film  can  ad- 
just the  contrast  characteristics  of  prints 
over  a  wide  range.  In  fact,  prints  are 
deliberately  made  more  "contrasty"  than 
the  actual  scenes  photographed. 


30 


INTERNATIONAL  PROJECTIONIST 


June  1949 


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Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


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Gentlemen:  Enclosed  find  S3.00  for  a   copy  of  PROTECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 

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VOLUME  24       •       NUMBER  7 


30c  A  COPY    •    S2.50  A  YEAR 


fAlRACLE  PRUGS  CANNOT  CURE  THIS  SICKNESS 


We  only  wish  there  were  a  miraculous  drug 
to  stop  a  man  from  worrying. 

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because  constant  worry  over  money  literally 
makes  sufferers  sick! 

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cannot  cure. 

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can! 

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your  company's  Payroll  Savings  Plan. 

Or,  if  you're  in  business  or  a  profession, 
enroll  in  the  Bond-A-Month  Plan  at  your 
local  bank. 

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INTERNATIONAL 

PROJECTIONIST 

With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


JULY  1949 


Number  7 


Index  and  Monthly  Chat 3 

Distortion  Factors  in  Sound  Re- 
production            5 

Robert  A.  Mitchell 

Cadmium-Mercury  Vapor 

Lamps:    Present  Status 8 

Henry  B.  Sellwood 

British  vs.  American  Projectors     10 
An  Exchange  of  Views 


High-Brightness  Carbon  Arcs 
M.  T.  Jones 
F.  T.  Bowditch 


12 


In  the  Spotlight 16 

Harry  Sherman 


Telecasts     18 

Newton's  Rings:    Yardsticks   of 

Optical  Science 19 

Bausch  &  Lomb  Optical  Co. 

Century  Projector  Develops 

Water-Cooled  Aperture  Unit         20 

Improved    Magnets    in    Peerless 
Lamps   20 

Larry  Davee  Heads  SMPE  Pro- 
jection Practice  Committee  .        20 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING   CO.,   INC. 

19  West  44  Street,  New  York   18,  N.  Y. 

R.  A.   ENTRACHT,  Publisher 

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appearing  in  signed  articles  in  its  columns. 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


MONTHLY   CHAT 

IT'S  time,  we  think,  that  an  inclusive 
look-see  be  had  at  the  various  devices 
now  being  employed  as  "effective"  cool- 
ing agents  for  motion  picture  equipment. 
The  problem  posed  by  the  ever-increas- 
ing amperages  utilized  for  projector  arcs 
in  all  categories  is  a  two-sided  one  in- 
volving the  arc  lamp  and  the  film.  Ob- 
viously, no  single  cooling  unit  can  solve 
this  duplex  problem,  notwithstanding  the 
preposterous  assertions  anent  effective- 
ness that  are  being  bandied  about  by  the 
sponsors  of  such  devices. 

The  word  "cooling,"  as  used  here  to 
denote  the  specific  function  of  a  unit,  is 
subject  to  considerable  elasticity  of  in- 
terpretation, depending  in  this  instance 
upon  which  horse  is  being  backed  by 
whom.  We  think  it  imperative  that  the 
true  functions  of  these  various  devices 
be  assayed  in  terms  of  actual  accom- 
plishment in  the  projection  room. 
Methods  of  cooling  now  being  advocated 
are: 

1.  Glass   filters   positioned  between   the 
arc  and  the  film. 

2.  Carbon  cooling  by  means  of  a  con- 
tinuous flow  of  water  around  the  jaw. 

3.  Blowers    which    direct    a    continuous 
blast  of  air  upon  the  aperture. 

4.  Water-cooling  of  the  aperture  plate. 

Certain  installations,  particularly  those 
de  luxe  theatres  and  drive-ins  which 
utilize  arc  amperages  ranging  up  to  190, 
employ  a  combination  of  the  aforemen- 
tioned cooling  aids;  and  not  a  few  situa- 
tions use  a  three-unit  combination — glass 
filter,  carbon  jaw  water-cooling,  and  a 
blower   unit. 

Glass  Filters.  These  filters  are  repre- 
sented by  their  sponsors  as  being  capable 
of  passing  all  the  "useful"  light  the  while 
they  filter  out  the  heat-producing  rays 
which  tend  to  buckle  and  otherwise  affect 
adversely  the  film.  IP  is  advised  by  a 
well-known  research  laboratory,  which 
has  had  extensive  experience  with  light- 
ing problems,  that  glass  filters  in  a 
typical  motion  picture  projection  set-up 
do  effect  a  reduction  of  about  50%  in 
the  heat  transmitted  to  the  film — but  at 
a  cost  of  about  a  20%  reduction  in  effec- 
tive light! 

"On  the  whole,"  states  the  laboratory 
report,  "our  tests  indicate  that  glass 
filters  are  quite  unsatisfactory  for  this 
specific  application."  Contrast  this  re- 
port with  the  statements  of  not  a  few 
projectionists  who,  although  admitting 
that  they  have  never  taken  readings  orf 
the  filter-equipped  set-up,  insist  that 
they  can  detect  with  the  naked  eye  a 
"great  improvement"  in  the  screen  image. 

IP  has  never  approved  the  use  of  glass 
filters  for  projection,  despite  the  off-the- 
cuff  reports  from  projectionists  with  as- 
sertedly  keen  vision.  Common  sense  would 
seem  to  dictate  the  answer  to  this  one. 

Carbon  Jaw  Water-Cooling.  Let  it 
be  said  at  the  outset  that  this  method  is 
strictly  a  protective  measure  for  lamp- 
{Continued  on  page  24) 


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INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


VOLUME  XXIV 


JULY  1949 


NUMBER  7 


Distortion  Factors  in  Sound  Reproduction 


SOUND  distortion  sometimes  occurs 
in  the  recording  process.  This  is 
especially  true*  of  commercial  gramo- 
phone records.  (Standard  disc  records 
manufactured  in  the  U.S.A.  during  the 
period  1940  to  1946  are  probably  the 
world's  worst.)  Nevertheless,  we  are 
cautioned  to  distinguish  between  "natu- 
ral distortion" — the  alteration  of  sound 
en  route  from  the  source  to  the  record- 
ist's microphone — and  the  unwanted  dis- 
tortion produced  by  the  recording  ap- 
paratus, by  the  recording  medium  and 
its  processing,  and  by  wear  or  mishan- 
dling on  the  recording  medium  (film  or 
disc) . 

In  other  words,  the  sound  imprisoned 
in  the  soundtrack  of  a  motion  picture 
film  is  not  necessarily  the  same  as  the 
sound  which  issued  from  the  original 
source,  but  it  must  be  the  same  as  the 
sound  which  the  microphone  "heard." 
If  it  is  not,  the  sound  is  distorted  in  the 
record,  and  there  is  little  or  nothing  that 
the  projectionist  can  do  about  it.  (Of 
course,  sounds  are  sometimes  deliber- 
ately distorted  in  order  to  create  special 
and  unusual  effects.) 

Typical  Distortion  Process 

How  does  sound  "distort"  as  it  passes 
from  its  source  to  the  microphone? 
Imagine  that  an  actor  is  speaking  in  a 
large  room  or  similar  "set."  Two  cam- 
eras at  some  distance  away  are  focused 
upon  him — one  camera  having  a  short- 
focus  lens  to  photograph  a  "long  shot," 
the  other  with  a  long-focus  lens  to 
give  a  closeup  view  of  the  actor's  face. 
(The  film  editor  will  cut  back  and  forth 


By  ROBERTA.  MITCHELL 

II 

between  these  two  shots  when  making  up 
the  final  negative  for  the  release  prints.) 

Now  suppose  that  the  microphone  is 
near  the  cameras — a  considerable  dis- 
tance from  the  actor.  The  actor  speaks 
his  "lines,"  both  cameras  shoot  the  scene 
simultaneously,  and  the  sound  recorder 
"in  sync"  with  the  cameras  photographs 
the  single  sound  negative  for  both 
cameras. 

When  the  "rushes"  are  shown  a  glar- 
ing error  appears.  The  long  shot  is  run 
first,  let  us  say,  the  sound  being  fur- 
nished by  a  separate  soundtrack  positive 
run  in  a  dummy  soundhead  synchronized 
with  the  picture  projector.  The  results 
are  satisfactory.  The  vast  room  appears 
on  the  screen,  and  when  the  actor  in  the 
background  speaks,  his  distant  voice 
echoes  through  the  room  in  an  entirely 
natural  way. 

Then  the  sound  positive  is  rewound 
and  run  with  the  closeup  shot.  The 
actor's  lips  move,  but  the  voice  is  thin 
and  distant,  as  though  someone  were 
speaking  from  another  room.  Obviously, 
the  closeup  must  be  retaken  with  the 
microphone  close  to  the  actor. 

The  same  mistake  can  be  made  on 
outdoor  locations.  We  can  tell  by  listen- 
ing whether  the  microphone  was  close  to 
the  sound  source,  or  far  away.  Sound 
really  does  change  in  quality  as  the 
distance  between  source  and  listener  is 
altered. 


Aural  nearness  is  suggested  by  a  heavy 
bass  response,  and  indoors  by  a  lack  of 
echo.  Aural  distance  is  characterized  by 
an  attenuation  of  bass  to  result  in  a 
"thin"  response,  and  indoors  by  echo  and 
reverberation. 

Recording,  Printing  Defects 

It  is  interesting  to  note  that  trick 
electrical  circuits  and  rerecording  proc- 
esses can  fake  these  effects.  The  poor 
carrying  power  of  the  bass  is  overcome 
in  outdoor  concerts  by  having  the  orches- 
tra perform  before  a  large  concave  sound 
reflector.  The  acoustic  engineer  is  able 
to  alter  the  "brilliance"  of  interior  re- 
cordings at  will  by  changing  the  "dead- 
ness"  of  the  set. 

Distortion  is  sometimes  introduced  into 
the  soundtrack  record  by  defects  in  the 
recording  apparatus  and  by  errors  of 
operation.  This  type  of  fault,  together 
with  distortion  introduced  by  the  film- 
processing  laboratory,  is  not  so  common 
as  it  used  to  be,  but  we  do  meet  it  once 
in  a  while,  especially  in  reissued  pro- 
ductions printed  from  duplicate  negatives 
made  from  positives. 

About  15%  of  the  sound  and  picture 
quality  is  lost  through  each  printing; 
hence  a  positive  made  from  a  duplicate 
negative  has  only  about  71%  the  quality 
of  a  positive  made  from  the  original 
negative'  (When  the  "dupe"  is  made 
from  a  "lavender  protection  print"  the 
percentage  of  quality  may  be  somewhat 
higher;  and  when  the  dupe  is  made  from 
an  old,  projection-worn  positive,  the  per- 
centage of  quality  is  shockingly  lower.) 

Sound   distortion    arising  through  de- 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


veloping,  printing,  and  poor  emulsion 
characteristics  is  always  of  the  non-linear 
type.  Overexposure  or  overdeveloping  of 
the  films  may  "fuzz"  the  records  so  that 
the  finer  striations  are  lost  and  the  wider 
ones  broadened,  and  place  variable- 
density  recording  in  the  region  of  chemi- 
cal fog  and  non-linear  exposure.  Under- 
exposure of  variable-density  tracks  may 
also  cause  a  loss  of  the  higher  frequen- 
cies and  more  or  less  non-linear  distor- 
tion. The  photographic  work  entailed  by 
sound-on-film  recording  is  delicate  and 
highly  speciabzed. 

Soundtrack  Modulation 

Overmodulation  of  both  types  of  sound- 
tracks introduces  serious  non-linear  dis- 
tortion. Fig.  4  shows  what  is  meant  by 
this  technical  term.  Three  sample  vari- 
able-area tracks  are  shown  in  the  draw- 
ing, each  track  being  a  record  of  a  pure 
(sine-wave)  144-d.v.  tone — the  D  an 
octave  below  "middle  D"  on  the  organ 
or  piano. 

The  topmost  track  is  completely  modu- 
lated. The  variations  are  of  such  ampli- 
tude that  they  completely  fill  the  length 
of  the  projector  soundhead  scanning 
beam  (0.084  inch).  It  is  impossible  to 
record  without  distortion  a  144-d.v.  tone 
of  greater  volume  than  the  one  shown  in 
this  track. 

Now,  the  next  track  shown  has  varia- 
tions of  greater  amplitude  than  this.  It 
is  easy  to  see  that  the  scanning  slit 
cannot  accommodate  waves  of  this  modu- 
lation. The  result  (shown  in  the  part 
labelled  "scanned  area")  is  a  distortion 
in  the  reproduced  wave — non-linear  dis- 
tortion. It  can  be  mathematically  demon- 
strated that  overmodulation  introduces 
strong  second,  fourth,  eighth,  and  other 
spurious   harmonics   into  the   sound. 

A  slight  degree  of  overmodulation  is 
sometimes  permissible  in  recordings  of 
thunder,  explosions,  and  other  exces- 
sively loud  sound,  which  are  noises 
rather  than  tones.  Distortion  is  present, 
of  course,  but  it  is  not  nearly  so  objec- 
tionable as  it  would  be  in  speech  and 
music. 

The  bottom  track  in  Fig.  4  is  somewhat 
undermodulated.  It  is,  in  fact,  a  high- 
fidelity  "low-level"  soundtrack.  If  the 
tone  so  recorded  is  reproduced  at  an 
optimum  average  level,  there  will  be 
plenty  of  leeway  for  louder,  as  well  as 
softer,  sounds.  Most  feature  films  have 
low-level  tracks. 

'Noisy'  Tracks  on  Decline 

Overmodulation  in  variable-density 
tracks  is  not  readily  detected  by  visual 
inspection,  but  the  effects  are  approxi- 
mately the  same  as  with  overmodulated 
variable-area  tracks.  Overmodulation 
may  also  arise  from  electrical  causes  in 
the  recording  amplifiers,  and  this  is  in- 
visible to  the  eye  (except  by  compari- 
son) . 

"Noisy"  sound-on-film  recording  is  for- 


tunately not  as  common  as  it  used  to  be, 
hence  silver-grain  noise,  photocell  hiss, 
and  the  noises  caused  by  slight  surface 
scratches  on  the  celluloid  side  of  the  film 
are  not  quite  so  troublesome  as  they  were 
in  the  days  before  "noiseless"  biased 
recording.  Deep  scratches,  "sprocket- 
ing"  marks,  etc.,  in  the  film  emulsion 
still  are  troublesome,  but  there  is  little 
that  the  projectionist  can  do  about  them 
except  complain  sharply  to  the  distribu- 
tors. (A  word  to  the  film  salesman  is 
sometimes  most  effective.) 

Images  of  the  sprocket  holes  of  the 
negative  or  of  frame  lines  in  the  sound- 
track area  produce  the  same  hums  and 
"motor-boating"  noises  which  appear 
when  the  soundhead  lateral  film  guides 
are  out  of  adjustment.  A  visual  exami- 
nation of  the  print  with  the  aid  of  a 
magnifying  glass  will  reveal  this  type  of 
trouble. 

We  have  spoken  at  length  of  the  vari- 
ous types  of  sound  distortion  which  may 
creep  into  the  film;  but  it  cannot  be 
gainsaid  that  most  cases  of  bad  sound 
originate  right  in  the  theatre.  This  is 
nearly  always  due  to  the  use  of  anti- 
quated and  defective  sound  equipment 
which  the  shortsighted  exhibitors  cling 
to  tenaciously. 

Trouble-Shooting  Guide 

Enough  has  been  said  to  aid  the  detec- 
tion of  distortion  at  once  and  to  make  a 
reasonably  good  guess  as  to  its  nature — 
frequency,  non-linear,  travel,  or  extrane- 
ous— so  we  shall  do  no  more  than  out- 
line a  trouble-shooting  guide  which  may 
further  the  friendly  cooperation  between 
projectionist  and  sound  service  engineer. 

1.  Frequency  Distortion.  Symp- 
toms:   Sound   which   is   tubby,   wooden, 


fh  n  n  cHT 

Scanned  Area 

V...... 

V 

t 

■;■   ...,,   ■ .  !':■■■■    :.  ?■•■:•....     '.;.  "»  :■ 


Fully  Modulated  Track* 

Scanned  Area 


QDDOO    J~ 

i^^r  ■  ■    t 

Overmodulated  TracK. 

Scanned  Area 


n  n  n  n  o 


T 


Low-Level  TracK, 


FIG.  4.  Variable-area  soundtracks  of  a  pure 
144  d.v.  tone.  The  extensions  labelled  "scanned 
area"  show  how  much  of  each  track  the  photo- 
cell "sees". 

Notice  that  the  overmodulated  track  pro- 
duces a  distorted  response  because  the  re- 
corded variations  have  an  amplitude  too  great 

for  the  dimensions  of  the  scanning  beam. 


metallic,  hollow,  or  in  which  excessively 
sharp  or  boomy  tones  appear  from  time 
to  time. 

Causes:  If  sharp  "peaks"  are  detected 
at  one  or  more  frequencies,  the  speaker 
units  or  amplifier  transformers  (coupbng 
and/or  output  transformers)  may  be  at 
fault.  Other  causes  are  faulty  acoustics 
of  the  auditorium  and  backstage  region, 
and  also  (very  rarely)  resonance  in 
amplifier  tubes  which  have  loose  ele- 
ments. Ordinary  frequency  distortion 
seldom,  if  ever,  originates  in  the  sound- 
head. 

Remarks:  The  use  of  pure-tone  (sine- 
wave)  frequency  test  films  or  disc  rec- 
ords1 and  an  output  meter  are  necessary 
for  an  intelligent  appraisal  of  the  defect. 

The  frequency-distortion  factor  of  the 
amplifier  at  different  volume  levels  is 
measured  by  connecting  the  meter  to  the 
amplifier  output;  but  whereas  the  speak- 
ers are  very  likely  to  be  the  chief  cause 
of  frequency  distortion,  it  is  imperative 
to  take  readings  from  the  meter  when 
connected  to  a  small  independent  ampli- 
fier of  uniform  response  characteristics 
and  a  microphone.  (An  acoustic  engi- 
neer's decibel  meter  is  ideal.) 

The  microphone  is  placed  in  the  audi- 
torium to  "listen"  to  the  test  tones  issuing 
from  the  stage  speakers.  Variations  of 
10  db  over  the  main  frequency  range  of 
100  to  4,000  d.v.  rmy  be  expected  of  the 
average  sound  syslsm,  but  the  existence 
of  sharp  resonance  peaks  greater  than 
5  db  is  cause  for  drastic  changes. 

A  difference  in  response  curves  ob- 
tained by  placing  the  microphone  in  dif- 
ferent parts  of  the  auditorium  indicates  a 
directional  characteristic  in  the  speakers 
— possibly  combined  with  unsatisfactory 
auditorium  acoustics.  In  theatres  having 
but  one  stage  speaker,  and  where  there  is 
a  balcony,  aim  the  speaker  at  the  middle 
of  the  front  of  the  balcony;  otherwise 
there  will  be  too  great  a  difference  in 
sound  volume  between  orchestra  and 
balcony.  If  the  speaker  is  aimed  at  the 
audience  downstairs,  it  is  entirely  pos- 
sible that  orchestra  patrons  will  com- 
plain of  too  much  volume,  while  gallery 
patrons  complain  of  too  little  volume. 
A  happy  medium  must  be  found  in  order 
that  everyone  be  satisfied. 

Loss  of  'Highs'  and  'Lows' 

2.  Loss  of  Highs.  (This  is  techni- 
cally a  special  case  of  frequency  distor- 
tion.) Symptoms:  Music  muffled,  as 
though  coming  through  a  curtain;  voices 
boomy  and  articulation  indistinct. 

Causes:  Soundhead  optics  out  of  focus 
or  azimuth  (also  causing  non -linear  dis- 
tortion) ;  dirt  in  the  gates  of  old-style 
(Continued  on  page  29) 


1  The  following  multifrequency  film  and  disc  test 
recordings  are  recommended:  "SMPE-Academy"  35- 
mm.  Multifrequency  Test  Film  Type  B,  No.  ASFA-1. 
"Columbia"  78-R.P.M.  Frequency  Response  Test  Rec- 
ord,  No.  10003-M. 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


/Pi  ctTTr  e  S\ 

i  \  \  \  \ .  \ x 

ON  THE     \ 


.,  ,^^_     .....      J^_—    i^-^'^BBt.1 


THE  STRONG  MOGUL 

PROJECTION      ARC      LAMP 

project*   the   MAXIMUM    light  that  film    will   accept   without   damage. 


USE  THIS  COUPON  TODAY  FOR  DEMONSTRATION  OR  LITERATURE 


Hi  THE  STRONG  ELECTRIC  CORPORATION 

\     '  31  City  Park  Avenue  Toledo  2,  Ohio 

V&wi  ■.  j  ■  y 
'£'#>v  "]  I  would  like  a  demonstration  of  Strong  lamps  in  my  theatre,  without  cost  or 

'.'v'.'.^  —       .... 

■^.,j!.  obligation. 

.i.y;         CH  Please  send  free  literature  on  the: 
t  VV r--.         CH  Mogul  Lamp  Q  Utility  Lamp  Q  Strong  Arc  Spotlamps 


""'     ,r|     ■•       ,        *  \tmf^  ■  f        r     (  D  Strong  Rectifiers  fj   Strong  Reflectors 

THEATRE 


.  „■  ■ , .  - ....-■  : ; J ■,.'.,    ■■■,,■ .:    ■ 


THEATRE- 
STREET- 


lOhwtk  lotHfuKiae  STRONG 'tte pidtitc  ia  tuffa/    J  city  and  state 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


DURING  the  past  few  months  IP  has 
received  an  ever-increasing  number 
of  inquiries  relative  to  the  present 
status  of  the  cadmium-mercury  vapor 
lamp.  Not  a  few  technicians  apparently 
believe  that  this  "new"  light  source  has 
reached  the  stage  of  development  where 
it  poses  a  serious  challenge  to  the  long- 
established  supremacy  of  the  carbon  arc 
in  the  motion  picture  field,  for  both 
studio  lighting  and  theatre  projection. 
The   spark  that  ignited   a   smoldering 


from  projects  sponsored  by  the  British 
Admiralty.  In  fact,  the  Carlson  paper 
previously  mentioned1  waSibased  largely 
on  data  supplied  by  the  Messrs.  Bourne 
and  Beeson,  of  British-Thomson-Houston 
.Co.,  Ltd.2 

So  much  for  background,  except  for 
the  notation  that  the  M.  V.  lamp,  even 
in  its  application-  to  the  motion  picture 
field,  is  definitely  not  "new."  N.  V. 
Philips  Co.,  of  Eindhoven,  Holland,  gen- 
erally regarded  as  one  of  the  outstanding 


arcs.  However,  the  highest  brightness 
portion  of  the  source  (%-inch  arc — 9.5 
mm)  extends  over  only  a  very  small 
area,  while  the  region  of  intermediate 
brightness  extends  over  a  large  volume. 
There  exists  considerable  uncertainty  as 
to  just  how  well  typical  projection  optical 
systems,  or  even  those  especially  devel- 
oped for  the  M.  V.  lamps,  will  be  able 
to  focus  a  light  source  extended  over 
such  a  large  volume. 

The  M.  V'.  lamp  is  credited  with  the 


Cadmium-Mercury  Vapor 


interest  in  the  M.  V.  lamp  on  the  part 
of  these  technicians  was  supplied  by  a 
paper  presented  by  F.  E.  Carlson,  of 
General  Electric  Co.,  before  the  SMPE 
in  the  Fall  of  19471;  and  this  interest 
was  fanned  into  flame  by  the  appearance 
subsequently  of  numerous  stories  in  the 
technical,  trade  and  lay  press  which  con- 
veyed the  idea  that  as  a  result  of  certain 
improvements  effected  the  M.  V.  lamp 
had  "arrived." 

Concerted  Promotion  Campaign 

Joining  G.  E.  in  energetic  promotion 
of  the  M.  V.  lamp  was  Westinghouse 
Electric  Corp.,  from  whence  emanated 
several  laudatory  press  releases,  the  while 
its  representatives  made  a  concerted 
frontal  attack  upon  the  ranks  of  "hard" 
lighting  (carbon  arc)  advocates  in  the 
West  Coast  studios. 

Nor  was  the  campaign  in  behalf  of  the 
M.  V.  lamp  confined  to  America :  marked 
advances  in  M.  V.  lamp  design  and  opera- 
tion were  scored  by  British  manufac- 
turers who  benefited  greatly  from  the 
accelerated  developmental  pace  resulting 

1  "New  Developments  in  Mercury  Lamps  for  Studio 
Lighting,"  by  F.  E.  Carlson;  J.  Soc.  Mot.  Pict.  Eng., 
Feb.    1948,    p.    122. 


Warm-up  characteristics  of  a   low- 
wattage     mercury    lamp.      Higher- 
wattage  types  require  substantially 
the   same    warm-up   time. 


Lamps:  Present  Status 

By  HENRY  B.  SELLWOOD 


technical  research  laboratories  in  the 
world,  pioneered  in  the  development  of 
the  M.  V.  lamp;  in  fact,  practically  all 
the  development  work  done  in  America 
on  this  unit  was  based  on  licenses 
granted  by  Philips. 

As  long  ago  as  1939  there  appeared 
in  these  columns  a  comprehensive  expo- 
sition3 anent  the  applicability  of  the 
M.  V.  lamp  to  motion  picture  work — ■ 
both  studio  lighting  and  theatre  projec- 
tion— and  the  intervening  years  have 
seen  no  marked  diminution  of  certain 
major  shortcomings  of  this  unit.  Among 
the  problems  which  still  plague  the 
M.  V.  researchers  are: 

1.  Shape  and  dimensions  of  the  light 
source. 

2.  Requisite  warmup  time,  ranging  from 
5  to  10  minutes  before  full  brightness 
is  attained. 

3.  Spectral  deficiencies. 

4.  Interruptions  due  to  lamp  failure, 
whether  at  the  expiration  of  useful 
life  or  through  sudden  breakage. 

None  of  the  aforementioned  deficien- 
cies has  been  overcome,  at  least  not  in 
terms  of  motion  picture  applications. 

M.  V.  Brightness  Values 

(1)  Published  curves  do  show  bright- 
ness values  in  the  range  or  near  to  the 
values  obtained  by  conventional  carbon 

y  "Color  Modified  Compact  Source  Lamp  for  Film 
and  Television,"  by  H.  K.  Bourne  and  E.  J.  G. 
Beeson;  British  Kinematography,  Vol.  11,  No.  4, 
Oct.   1947,   p.    107. 

3  "Film  Projection  by  Discharge  Lamps,"  by  G.  Hel- 
ler, Philips  Technical  Laboratories;  IP  for  Aug. 
1939,    p.    7. 


ability  to  produce  a  light  intensity  of 
the  order  of  800  candles  per  sq.  mm. 
This  figure,  apparently  predicated  on 
operation  of  the  lamp  at  its  full  rating 
of  10,000  watts,  approximates  the  bright- 
ness of  a  13.6  regular  high-intensity  car- 
bon arc  pulling  125-130  amperes. 

In  a  demonstration  of  a  M.  V.  lamp 
witnessed  by  the  writer,  however,  the 
demonstrators  displayed  obvious  reluct- 
ance to  "push"  the  lamp  to  its  full  rated 
capacity  (for  reasons  best  known  to 
themselves)  and  the  writer  estimated  that 
the  peak  wattage  used  was  of  the  order 
of  5-6000. 

It  follows,  naturally,  that  peak  rated 
wattage  must  be  utilized  to  attain  full 
brightness  output,  the  ratio  of  diminish- 
ing brightness  being  disproportionately 
greater  than  the  percentage  of  reduced 
wattage. 

Warmup  and  Starting   Requisites 

(2)  The  M.  V.  Lamp  requires  a 
warmup  time  to  reach  full  brightness, 
variously  reported  as  from  5  to  10 
minutes.  Also,  the  lamps  are  more  diffi- 
cult to  strike  when  hot  than  when  cold. 
In  order  to  provide  quick  availability  of 
full  light  output,  it  is  apparently  neces- 
sary to  provide  ovens,  standby  power,  or 
some  other  means  for  accomplishing  the 
same  result. 

When  final  operating  temperature  is 
attained,  the  M.  V.  lamp  develops  a  high 
pressure  which  is  in  the  neighborhood 
of  from  10  to  40  atmospheres.  Due  to 
the  large  volume  of  these  lamps  and  the 
high  pressure,  there  is  a   hazard   stem- 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


He  gives  shape  to  things  to  come... 


HIS  the  ability  to  see  each  script  through 
the  camera's  eye  ...  to  picture  with  brush 
and  pencil  the  story's  dramatic  high- 
lights . . .  and,  finally,  to  shape  sketches 
into  settings  of  authentic  merit. 

He  is  the  screen's  art  director,  at  once 
responsive  and  responsible.  Not  only 
must  he  be  sensitive  to  the  mood  of  the 
story . . .  giving  full  consideration,  as  well, 
to   the   personality    of  the    star  .  .  .  but 


also  he  must  be  constantly  aware  of  the 
practicalities  of  motion  picture  produc- 
tion, be  able  to  work  closely  with  scores 
of  crafts  within  and  without  the  studio. 
Above  all,  the  art  director  knows  the 
importance  of  the  faithful  reproduction 
of  the  values  he  creates ...  an  assignment 
he  is  well  content  to  see  competently 
handled  by  Eastman's  famous  family  of 
motion  picture  films. 


m^y 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.    Y. 

J.    E.    BRULATOUR,    INC.,    DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •     HOLLYWOOD 


ming  from  possible  breakage.  Provision 
must  be  made  to  protect  equipment  and 
personnel  from  the  flying  fragments  of 
an  exploding  lamp. 

These  hazards,  of  course,  are  present 
only  when  the  lamp  is  hot  and  not  at  all 
when  it  is  completely  cold. 

Several  years  ago  Philips  exhibited  a 
motion  picture  projector  utilizing  the 
M.  V.  lamp  as  a  light  source  in  which 
two  lamps  were  mounted  on  a  turret 
which,  if  one  lamp  failed,  would  enable 
immediate  substitution  of  the  second 
lamp.  Of  course,  this  procedure  requires 
that  the  replacement  lamp  be  already 
warmed  up,  at  reduced  wattage  by  means 
of  a  resistor,  so  as  to  be  ready  for  in- 
stant operation. 

Even  this  arrangement  leaves  much  to 
be  desired  in  terms  of  operating  effi- 
ciency, because  the  inoperative  lamp 
could  not  be  replaced  until  it  had  com- 
pletely cooled  to  room  temperature. 
Carlson  mentions1  a  method  whereby  a 
standby  lamp  may  be  first  warmed  up 
and  then,  by  reducing  the  current  to  10 
to  15%  of  its  full  load  value,  is  left  to 
"simmer"  until  needed. 

Spectral  Characteristics  Data 

(3)  The  most  important  recent  im- 
provement in  the  spectral  characteristics 
of  the  M.  V.  lamp  was  the  introduction 
in  types  of  1000  watts  or  more  of  cad- 
mium and/or  zinc  which  produce  not 
only  a  generous  amount  of  red  radiation 
but  also  radiation  in  the  blue-green  re- 
gion. 

Westinghouse  attempted  to  overcome 
the  characteristic  spectral  deficiency  of 
the  cadmium-M.  V.  lamp  by  coating  the 
surface  of  the  bulb  with  phosphorus  and 
thus  convert  some  of  the  ultraviolet  of 
the  mercury-cadmium  into  visible  light 
in  the  red  region.  This  move  would  seem 
to  indicate  less  than  complete  confidence 
in  the  spectral  characteristics  of  the 
M.  V.  lamp  even  with  the  addition  of 
cadmium. 

There  exists  an  element  of  doubt 
among  technicians  as  to  the  permanence 
and  continuing  efficiency  of  phosphorus 
when  used  as  a  fluorescent  material  for 
such  a  purpose.  In  any  event,  and  with 
the  best  will  in  the  world  toward  the 
M.  V.  lamp,  it  would  seem  that  this  does 
not  have  the  essentially  continuous  spec- 
trum obtainable  with  the  carbon  arc. 

(4)  Interruption  of  operation  due  to 
the  failure  of  a  M.  V.  lamp,  due  to  either 
the  expiration  of  its  useful  life  or  through 
breakage,  would  be  economically  un- 
sound in  studio  work  and  utterly  intoler- 
able in  projection  work.  The  mounting 
of  several  lamps  on  a  turret  and  the 
adoption  of  the  "simmering"  technique 
would  seem  to  be  wholly  inadequate  for 
production  work  and  impossible  for  pro- 
jection. 

The  light  output  of  a  M.  V.  lamp  falls 


British  vs.  American  Projectors 

In  which  the  Technical  Editor  of  "Ideal  Kinema"  (London)  and  the 

Editor  of  IP  exchange  views  on   the  relative   merits  of   British   and 

American   soundfilm  projection   equipment. 


By  R.   H.  CRICKS 

WARFARE  is  imminent  between  the 
United  States  and  Great  Britain — ■ 
or  is  it?  I  referred  previously  to  descrip- 
tions in  International  Projectionist  of  re- 
cent British  projectors,  and  expressed 
the  opinion  that  this  equipment  was 
years  ahead  of  American  design.  One 
could  hardly  expect  IP,  as  a  patriotic 
American  publication,  to  subscribe  to 
these  views.  In  the  March  issue  (p.  5) 
the  statement  is  made  that  at  least  four 
American  machines — Brenkert,  Century, 
Motiograph  and  Simplex — "accomplished 
precisely  the  same  thing,  not  only  in 
America,  but  in  far-flung  corners  of  the 
earth  which  never  see  a  serviceman." 

We  have  not,  of  course,  seen  any  of 
these  machines  in  its  complete  form  in 
this  country:  the  Brenkert  and  Motio- 
graph we  do  not  know  at  all ;  the  Simplex 
we  see  only  fitted  with  other  makes  of 
sound;  while  the  Century  is,  of  course, 
the  Westar  machine  fitted  with  Westrex 
sound.  I  am,  therefore,  at  rather  a  dis- 
advantage in  expressing  opinions  on  the 
subject. 

Fifth  Column  Activities? 

But  I  must  confess  to  some  surprise  at 
reading  comments  by  "a  British  techni- 
cian of  vast  experience"  who  apparently 
has  no  use  for  British  equipment  and 
who  has  acquired  the  American  idiom. 


His  remarks  are  worth  quoting  in  full: 

"I  fully  agree  with  remarks  in  IP  for 
December  1948  last  (Monthly  Chat, 
p.  3).  I  should  dearly  like  to  write  an 
article  debunking  these  British  pro- 
jectors of  recent  design,  but,  obviously, 
I  cannot.  I'm  all  for  standardization 
of  equipment,  thus  I  think  that  stuff 
like  the  SUPA  is  completely  retro- 
grade. 

"Any  exhibitor  who  is  kidded  into  buy- 
ing one  of  these  outfits  is  completely 
tied  to  one  firm  for  many  years  to 
come.  From  the  projectionist's  view- 
point, such  apparatuses  mean  that  he 
has  either  got  to  be  a  superserviceman 
to  maintain  it  or  he  must  be  a  brainless 
coot. 

"The  Kalee  isn't  quite  so  unorthodox  a 
design,  but  here  again  the  buyer  is  tied 
down  to  one  supplier  for  any  future 
development.  I  can  understand  and  ap- 
preciate the  utility  of  a  streamlined 
aircraft,  automobile  or  railroad  loco- 
motive, but  I'm  darned  if  I  can  see 
the  sense  of  a  streamlined  projector. 
And  streamlining  is  about  the  only 
'modern'  aspect  of  these  mechanisms." 

The  SUPA  Projector  Achievements 

Now,  the  SUPA  has  had  its  teething 
troubles.  But,  despite  the  views  ex- 
pressed by  this  British  technician,  I  still 
consider  it  the  most  outstanding  devel- 
opment in  projection  equipment  for  half 
(Continued  on  page  27) 


off  gradually  to  about  75%  of  its  initial 
value  at  the  end  of  its  life,  owing  to 
blackening  of  the  bulb.  Gradual  black- 
ening of  the  bulb,  however,  falls  far 
short  of  a  satisfactory  warning  signal  to 
any  technician  in  the  graphic  arts  field. 
One  other  point  bearing  on  the  safety 
factor  seems  worthy  of  mention  in  pass- 
ing. To  quote  Carlson1: 

Movie  Application  Still  Distant 

"Mercury  lamps  emit  radiations  in 
that  portion  of  the  ultraviolet  spectrum 
which  cause  sunburn  or  conjunctivitis. 
These  rays  are  absorbed  and  rendered 
harmless  by  the  outer  bulb  which  is 
used  with  most  such  sources.  Since  such 
an  outer  envelope  is  not  used  with  the 
mercury  vapor  lamps  described  here 
(i.e.,  for  motion  picture  use — Ed.)  it 
follows  that  they  must  be  enclosed  in 
housing  providing  the  same  degree  of 
protection  that  prevails  for  carbon  arcs." 
There  is  no  intent  here  to  minimize 
the  importance  of  the  M.  V.  lamp  as  a 


most   worthy   entry   into   the   list   of   effi- 
cient light  sources.  On  the  contrary,  there 
are    innumerable     applications    wherein 
the  M.  V.  lamp  might  well  prove  itself 
at  least  the  equal  if  not  actually  superior 
to  any  other  known  artificial  light  source. 
It    seems    obvious,    however,    that    in 
terms  of  specific  application  to  the  mo- 
tion picture  field,  whether  in  the  studio 
or  the  theatre,  the  M.  V.  lamp  still  falls 
short  of  meeting  essential  requirements. 
Perhaps  the  best  summation  of  the  pres- 
ent status  of  the  M.  V.  lamp  was  given 
by  A.  G.  Penny  in  a  recent  lecture  be- 
fore the  British  Kinematograph  Society4: 
"The    carbon    arc    still    remains    the 
best  all-around  light  source  for  kinema 
projection.     It   is    my   belief   that   this 
situation   will   change,   but  I   feel   that 
some  new  discovery  in  the  world  of  pure 
science  is  necessary  before  the  arc  re- 
linquishes  the    supremacy   it    has    held 
for  the  last  50  years." 

4  "Can    the    Discharge    Lamp    Oust    the    Arc";    The 
Ideal    Kinema.    (London),    May    5,    1949. 


10 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


/  *^        MAGNA 


M- 


£W 


MAGNARC 


TRADE    MARK    REG 


1-KW  TO  70  AMPS 


HY-AX"  ARC  MAGNET 
HY-LUMEN      REFLECTOR 


More  light  at  40  to  70  amperes  than  ever  thought  possible. 
.  .  .  Equals  and  excels  any  reflector  lamp  to  85  amperes,  whether 
they  be  unapproved  water-cooled  or  resurrected  hi-lows.  .  .  . 
Highest  ratio  of  screen  lumens  per  watt  consumed  at  the  arc. 
...  At  70  amperes,  with  a  projector  having  an  efficient  DISC 
type  revolving  shutter,  it  develops  the  maximum  white  light  that 
can  be  used  without  a  heat  filter.  .  .  .  Operating  costs  under  these 
conditions  are  far  below  that  of  85-ampere  lamps. 

Magnarc  Lamps  assure  80%  side-to-center  (SMPE  Standard) 
screen  light  distribution,  not  a  deceptive  60%  or  "Hot  Center." 
.  .  .  They  are  all  Und.  Lab.,  Inc.  listed.  .  .  .  They  are  not  in- 
surance hazards.  .  .  .  They  are  and  have  been  for  years  "The 
Standard  of  Comparison"  and  "The  First  Choice"  of  large 
and  small  theatres,  drive-ins,  and  the  motion  picture  industry 
in  general! 


1 1 


ALWAYS  THE  FINEST,  ALWAYS 


/ 1 


120-180  AMPERES 


TRADE    MARK    REG 


NEW    MAGNETIC    STABILIZER 

This  modern  lamp  produces  all  the  light  there  is. 
...  It  is  the  standard  equipment  of  the  nation's  largest 
and  finest  theatres.  .  .  .  Used  by  90%  of  the  largest 
Drive-In  Theatres. 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  white  light  volume 
when  used  with  projectors  that  have  efficient  DISC 
type  revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions.  .  .  .  They  are  Und.  Lab.,  Inc. 
listed  and,  therefore,  not  insurance  hazards. 


EXPERIMENT? 


i  i 


J.E.McAULEY  MFG. CD. 


552-554    WEST   ADAMS    STREET 

CHICAGO   6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


11 


FIG.   1 — Side  view  of  arc-lamp   mechanism   incorporating   water-cooled 
positive  and  negative  jaws. 


FIG.  2 — Detailed  view  of  water-cooled  positive  jaws  on  arc-lamp 


High-Brightness  Carbon  Arcs 


By  M.  T.  JONES  and  F.  T.  BOWDITCH 

National   Carbon   Company,   Cleveland,   Ohio 


THE  high-intensity  carbon  arc  finds 
extensive  use  in  the  motion  picture 
industry  because  of  several  impor- 
tant attributes.  First,  it  has  a  very  high 
brightness  over  an  area  of  adequate  size 
and  shape.  An  effective  light-collecting 
system  thus  can  be  designed  to  concen- 
trate the  necessary  lumens  on  a  projector 
aperture  within  the  limits  of  optical 
speed  which  can  be  utilized  effectively 
by  the  projection  lens.  Second,  the 
light  is  of  excellent  color  quality  for  the 
faithful  photography  and  projection  of 
both  black-and-white  and  colored  motion 
pictures.  Third,  the  carbon-arc  lamp  has 
a  high  degree  of  mechanical  reliability 
insuring  a  constant  trouble-free  delivery 
of  light  during  the  period  required  to 
project  one  reel,  or  to  photograph  a 
scene. 

This  first  attribute  of  a  continuously 
maintained  high  brightness  has  been  the 
subject  of  investigation  by  many  scien- 
tists both  here  and  abroad.  In  our  own 
laboratories,  we  are  continually  search- 
ing for  ways  of  making  and  operating 
carbon  arcs  which  will  raise  the  ceiling 
of  brightness,  although  we,  in  common 
with  other  investigators,  have  at  times 
held  the  opinion  that  certain  facts  of 
nature  have  determined  limits  beyond 
which  we  may  never  be  able  to  go. 

Basis  for  Water-Cooling 

This  article  is  concerned  with  a  meth- 
od of  operating  carbon  arcs  which  has 
been  found  useful  whenever  the  highest 
brightness  and  smoothest  operation,  par- 
ticularly at  high  currents,  is  desired. 
This    involves    the    use    of    water-cooled 

tJ.  Soc.  Mot.  Pirt.  Eng.,  April  1948. 


jaws  for  both  the  positive  and  negative 
carbons.  When  these  jaws  are  properly 
employed  in  a  manner  to  be  described, 
they  permit  the  effective  utilization  of 
the  high-current  densities  required  for 
optimum  high-brighntess  performance. 

Mention  has  been  made  previously  of 
the  advantages  inherent  in  water-cooled 
jaw  operation.  The  continued  confirma- 
tion and  extension  of  these  earlier  find- 
ings has  made  appropriate  this  article 
devoted  more  particularly  to  a  descrip- 
tion of  the  operating  methods  involved. 

Critical  Current  Value 

The  major  source  of  brightness  in  the 
high-intensity  carbon  arc  is  the  so-called 
line  radiation  resulting  from  energy  ex- 
changes between  rare-earth  atoms  and 
electrons  in  the  gas  ball  within  the  posi- 
tive crater.   It  is  apparent  that  the  higher 


the  current  on  a  given-sized  carbon,  the 
higher  the  electron  density  in  the  crater 
will  be.  Thus  a  greater  number  of  en- 
ergy exchanges  is  to  be  expected,  with  a 
corresponding  increase  in  crater  bright- 
ness. 

However,  as  the  current  is  increased 
beyond  a  rather  critical  value,  an  over- 
load phenomenon  is  encountered,  which 
is  usually  characterized  by  noise  and  un- 
steadiness. In  practical  operation,  there- 
fore, the  user  must  be  content  with  the 
brightness  obtainable  at  currents  below 
this  overload  point.  With  the  present 
13.6-mm  super  high-intensity  projector 
carbon,  for  instance,  the  maximum  rec- 
ommended current  is  170  amperes. 

A  theory  of  overload  has  been  ad- 
vanced which,  briefly,  is  analogous  to  the 
violent  boiling  of  a  kettle  of  water  which 
accompanies  a  high  rate  of  energy  input 
from  a  turned-up  burner.  If,  however,  a 
cooling  coil  be  inserted  in  the  kettle 
(analogous  to  providing  improved  cool- 
ing of  the  positive-carbon  crater)  enough 
of    the    input   energy    can    be    absorbed 


The  effects  of  positive-crater  cooling  are  described,  and  a  suitable  apparatus 
for  this  purpose  is  illustrated.  The  combination  of  specially  made  high- 
brightness  carbons  with  water-cooled  operation  permits  the  use  of  higher  cur- 
rents without  unsteadiness,  and  so  gives  a  higher  brightness  than  has  been 
achieved  in  conventional  air-cooled  operation.  This  is  attributed  to  the  fact 
that  effective  cooling  of  the  positive  carbon  removes  energy  which  would 
otherwise  be  dissipated  in  turbulent  volatilization,  so  that  a  higher  current 
density  can  be  achieved  in  the  light-producing  gas  ball  before  overload 
turbulence  occurs. 

A  considerable  part  of  the  more  efficient  crater  cooling  is  attributable 
to  the  carbons  themselves,  since  they  will  operate  without  water-cooling  at 
higher  currents  and  brightnesses  than  other  types  of  equal  size. 

Within  the  limit  of  satisfactory  air-cooled  operation  with  a  given  carbon, 
efficient  water-cooling  always  reduced  the  light  produced  at  a  given  current; 
the  ability  to  operate  with  higher  brightness  at  higher  currents  was  thus 
gained  at  the  expense  of  a  lower  current  efficiency.  Carbons  designed  for 
efficient  air-cooled  operation  gave  no  better  result  with  water-cooling:  the 
current  efficiency  was  sacrificed  with  no  gain  in  maximum  brightness. 


12 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


so  that  the  boiling  will  subside,  and  an 
even  higher  rate  of  energy  input  toler- 
ated without  turbulence. 

So  it  is  with  the  carbon  arc.  Effective 
cooling  of  the  positive  carbon  dissipates 
peaceably  energy  which  might  otherwise 
produce  turbulence,  so  that  a  given-sized 
carbon  can  be  designed  to  carry  more 
current. 

It  has  been  pointed  out  that  water- 
cooled  operation  is  accompanied  by  a 
lower  anode  drop,  so  that  this  also  con- 
tributes importantly  to  the  reduction  in 
anode  energy  per  ampere.  By  means  of 
optimum  cooling,  through  the  use  of 
properly  constructed  carbons  in  water- 
cooled  jaws,  the  gas  ball  in  the  crater 
space  can  thus  be  provided  with  a  denser 
population  of  electrons  before  the  limit 
of  their  peaceful  absorption  on  the  crater 
surface  is  attained. 

A  13.6-mm  size,  for  instance,  can  be 
made  to  operate  at  350  amperes  and 
40,000  screen  lumens,  instead  of  170 
amperes  and  only  20,000  lumens;  while 
water-cooled  16-mm  carbons  have  been 
operated  at  currents  up  to  500  amperes. 
It  is  advantageous  also  to  cool  the  nega- 
tive carbon,  particularly  at  high  cur- 
rents, as  will  be  pointed  out  later. 
Crater  Brightness  vs.  Consumption 

Other  workers  have  determined  cer- 
tain fundamental  relationships  charac- 
teristic of  the  carbons  and  methods  of 
operation  with  which  they  were  familiar, 
and  which  predict  levels  of  operation 
significantly  exceeded  by  the  procedures 
described  here.  For  instance,  Finkeln- 
burg1  reports  an. empirical  relationship 
between  crater  brightness  and  consump- 
tion rate,  which  he  found  characteristic 
of  the  carbons  and  methods  of  operation 
available  to  him  in  Germany.  At  2000 
mm  per  hour  (79  inches  per  hour)  for 
instance,  this  relationship  predicts  an 
average  brightness  of  140,000  stilb  (1260 
candles  per  sq.  mm.)  As  will  be  shown 
later,  this  value  has  been  exceeded  by 
about  50%  by  taking  advantage  of  the 
cooling  methods  described  in  this  paper. 

In  a  Second  instance,2  Hallett,  in  Eng- 
land, recently  proposed  a  so-called  "mas- 
ter curve,"  relating  maximum  crater 
brightness  to  current  density.  While 
Hallett  and  his  associates  were  familiar 
with  the  advantages  of  water-cooled  jaw 
operation,  particularly  as  this  affects  car- 
bon consumption,  no  mention  is  made  of 
the  ability,  with  specially  made  carbons, 
to  achieve  a  much  higher  maximum 
brightness  with  water-cooled  jaws  than 
with    the    conventional    radiation-cooled 

1  W.  Finkelnburg,  "The  High-Current  Carbon  Arc," 
Field  Information  Agency,  Technical,  Office  of  Mili- 
tary Government  for  Germany  (US).  Final  Report 
1052.  (Office  of  Technical  Services  P.B.  No.  81644). 
Review  published  J.  Soc.  Mot.  Pict.  Eng.,  vol.  52,  pp. 
112-113;   January,   1949. 

2  C.  G.  Heys  Hallett,  "Recent  developments  in  car- 
bon arc  lamps,"  /.  Brit.  Kinemato graph  Soc,  vol.  11, 
p.   188;    December,   1947. 


contacts.  By  such  means,  we  have  found 
it  possible  in  many  cases  to  achieve 
brightnesses  significantly  in  excess  of  the 
maximum  predicted  by  the  "'master 
curve." 

It  should  be  pointed  out  again  that 
this  advance  is  not  the  result  of  water- 
cooled  operation  alone,  since  it  will  be 
apparent  later  that  carbon  design,  spe- 
cially directed  toward  water  cooling,  is 
an  even  more  important  factor. 

The  experimental  apparatus  in  which 
our  tests  were  made  is  shown  by  the  suc- 
ceeding figures.  Fig.  1  shows  a  side 
view  of  the  arc-lamp  mechanism,  which 
is  a  special  adaptation  of  a  general-pur- 
pose test  lamp  made  by  Mole-Richardson 
Co.  The  water-cooled  positive  and  nega- 
tive heads,  made  of  silver  and  copper, 
respectively,  the  floating  chuck  for  driv- 
ing the  positive  carbon,  and  the  arrange- 
ment of  the  current  leads  to  protect  them 
from  the  direct  radiation  of  the  arc  and 
to  insure  a  symmetrical  magnetic  field 
around  the  arc,  are  items  of  particular 
interest. 

Physical  Testing  Set-Up 

The  floating  chuck  at  the  right  of  the 
picture  grips  the  positive  carbon  securely 
for  purposes  of  rotation  and  forward 
feed,  while  at  the  same  time  permitting 
the  end  of  the  carbon  to  oscillate  a  bit 
as  demanded  by  the  rigid  clamping  of 
the  front  end.  The  water-cooling  circuit, 
with  a  coil  spring  counter-acting  the 
sideways  loading  which  the  piping  im- 
poses on  the  upper  jaw,  is  another  im- 
portant feature. 

This  front-end  clamping  is  more  clear- 
ly seen  in  Fig.  2,  which  shows  the  positive 
water-cooled  jaws  with  the  near  current 
lead  removed,  and  the  upper  jaw  raised 
to  expose  the  construction  features  more 
clearly.  These  include  a  rigidly  mourfjied 
lower  jaw,  with  the  upper  jaw  free  to 


move  vertically  under  spring  pressure. 
The  location  of  the  springs  underneath, 
shielded  from  the  radiation  in  a  counter- 
bored  hole  in  the  lower  water-cooled  jaw, 
is  an  important  feature. 

The  guides  for  positive  alignment  of 
the  upper  jaw  insure  the  rigid  clamping 
of  the  positive  carbon  along  a  predeter- 
mined axis.  The  upper  jaw  is  sloped 
backward  along  the  edge  nearest  the  arc 
to  permit  free  arc-flame  travel  at  short 
carbon  protrusion  with  minimum  damage 
to  the  jaw. 

Figure  3  shows  a  front  view  of  the 
mechanism  with  all  connections,  and 
both  positive  and  negative  carbons,  in 
place.  Special  attention  is  directed  to 
the  negative  head,  which  consists  simply 
of  a  fixed  -  bore  water  -  jacketed  copper 
tube.  An  unplated  negative  carbon  of 
small  diameter  (5/16  inch)  is  employed, 
with  a  short  protrusion.  Current  is  con- 
ducted directly  from  this  water-cooled 
negative  head,  so  that  the  carbon  carries 
current  only  along  the  short  protrusion. 

Positive  Jaw  Critical  Area 

The  choice  of  silver  material  for  the 
positive  head  and  copper  for  the  negative 
is  based  upon  the  following  considera- 
tions. A  material  for  this  service  must 
combine  a  high  electrical  and  thermal 
conductivity  with  freedom  from  excessive 
corrosion  and  rapid  wear  in  service.  Cop- 
per most  economically  fulfills  these  re- 
quirements in  so  far  as  the  negative 
head  is  concerned.  However,  this  same 
material  fails  because  of  excessive  wear 
in  the  positive  head.  This  is  because 
copper  is  plated  from  the  jaws  onto  the 
carbon,  and  this  then  scores  the  jaws  as 
it  is  dragged  around  with  carbon  ro- 
tation. 

The  reason  this  destructive  effect  is 
confined  to  the  positive  Jaw,  while  the 
very  similar  usage  in  the  negative  gives 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


13 


-22000 
i 

CO 
10 
bJ 

Z 
H 
I 
O 
g    1000 

CO 


L 

?- 

/ 
/ 

/ 

A 

200 


300  400 

ARC  CURRENT-AMPERES 


no  trouble,  is  believed  to  be  associated 
with  the  direction  of  current  flow,  and 
the  rectifying  action  of  the  copper-oxide 
and  sulfide  films  which  tend  to  form 
along  the  copper-carbon  contacts.  These 
films  are  conductive  in  the  direction  of 
current  flow  from  carbon  to  copper  in 
the  negative  holder,  but  they  tend  to 
block  current  flow  from  copper  to  car- 
bon in  the  positive. 

Since  the  distance  between  the  jaw 
and  the  carbon  is  so  short,  a  contact  drop 
of  only  1  volt  produces  a  gradient  of 
perhaps  several  thousand  volts  per  mm 
across  the  rectifying  film.  This  is  suffi- 
cient to  rupture  the  film  "and  draw  cop- 
per ions  across  the  gap  to  be  neutralized 
on  the  carbon.  Silver  oxide  and  sulfide, 
on  the  other  hand,  are  good  conductors 
with  no  rectifying  properties,  and  so  sil- 
ver is  free  from  this  difficulty.  The  jaws 
illustrated  here  have  operated  several 
hundreds  of  hours,  many  of  them  at  high 
currents  from  300  to  500  amperes,  with 
no  significant  wear  and  every  indication 
of  prolonged  satisfactory  performance. 

Carbon  Rotational  Speed 

For  purposes  of  securing  comparative 
data,  it  is  necessary  that  certain  operating 
conditions  be  held  constant.  Factors  de- 
termining the  choice  of  these  conditions 
in  the  tests  to  be  described  were  as 
follows : 

The  speed  of  rotation  of  the  positive 
carbon  was  chosen  at  15  r.p.m.  How- 
ever, the  exact  speed  is  not  critical  so 
long  as  it  is  above  the  minimum  required 


2000 


FIG.  4  (left):  Comparison  of 
air-  and  water-cooled  opera- 
tion for  new  higlter-curre.  t 
13.6-mm  "high-brightness" 
carbon. 

FIG.  5  (right):  Comparison  of 
air-  and  water-cooled  opera- 
t  on  for  13.6-mm  super  high- 
intensity  projector  carbon. 


(M 

5 


1000 


0 
100 


200  300  400 

ARC  CURRENT- AMPERES 


500 


to  insure  a  straight  crater  face.  In  the 
test  lamp  used,  the  angle  between  the 
positive  and  negative  carbon  is  adjust- 
able over  a  wide  range.  This  angle  is 
not  ordinarily  critical  over  a  range  be- 
tween about  45  and  60  degrees  of  the 
negative-carbon  axis  below  a  horizontal 
positive. 

For  the  tests  to  be  described,  the  half- 
way value  of  53  degrees  was  chosen.  At 
shallower  angles,  the  positive  tail  flame 
is  thrown  objectionably  close  to  the 
upper  jaw,  the  arc  is  less  stable,  and  it 
is  more  difficult  to  hold  a  straight  crater. 
At  steeper  angles,  the  negative  flame 
tends  to  pass  in  front  of  (rather  than 
into)  the  crater,  so  that  the  arc  is  more 
difficult  to  control,  at  least  without  the 
aid  of  an  auxiliary  magnetic  field. 

In  order  to  insure  optimum  cooling, 
the  protrusion  of  the  positive  carbon  be- 
yond the  jaw  should  be  held  to  as  small 
a  value  as  possible  consistent  with  ade- 
quate jaw  protection.  A  protrusion  of 
V2  inch  was  used  with  16-mm  carbons- 
and  only  x/4  inch  with  9-mm  carbons. 

The  use  of  a  small  negative  carbon 
with  a  short  protrusion  contributes  im- 
portantly to  a  stable  arc  at  high  cur- 
rents. The  small  carbon  spindles  to  a 
sharply  defined  tip  area,  which  is  com- 
pletely and  stably  filled  with  the  nega- 
tive flame  at  a  current  density  of  ap- 
proximately 30  amperes  per  sq.  mm. 
(This  compares  with  a  positive-crater 
current  density  of  between  1  and  3  am- 
peres per  sq.  mm. 

It  is  obvious  that  there  is  much  less 


freedom  for  arc  wandering  here  as  com- 
pared with  the  comparatively  blunt  point 
formed  on  the  much  larger  plated  nega- 
tives conventionally  employed  in  heavy- 
current  service.  The  advantages  of  the 
small  water-cooled  negative  are  more 
pronounced  as  the  current  is  increased. 

Maximum  Current  Limits 

The  determination  of  the  maximum 
performance  of  a  given  carbon  is  depen- 
dent upon  the  choice  of  a  maximum 
operating  current.  This  was  chosen  at  a 
value  a  little  below  that  which  resulted  in 
unstable  operation.  Over  a  wide  range 
of  sizes  and  types  of  positive  carbons,  the 
same  5/16-inch  water-cooled  negative 
was  employed,  giving  very  satisfactory 
operation  at  all  currents  from  90  to  500 
amperes. 

Positive  carbons  from  9  to  16  mm  in 
diameter  have  been  specially  designed  to 
take  advantage  of  the  efficient  cooling 
provided  in  the  apparatus  shown  in  Fig. 
1.  The  first  of  these  is  a  13.6-mm  carbon 
opration  at  290  amperes.  One  of  the  out- 
standing features  of  this  type  of  carbon 
is  its  high  thermal  conductivity,  which  is 
essential  to  the  efficient  transfer  of  heat 
from  the  floor  of  the  crater  to  the  water- 
cooled  jaws.  This  is  an  important  link 
in  the  cooling  system  required  to  post- 
pone overload  turbulence  to  higher  cur- 
rent densities,  in  accordance  with  the 
theories  previously  expressed. 

Carbon  composition,  as  well  as  water 
cooling,  are  thus  involved  in  the  achieve- 
ment of  crater  brightness  in  excess  of 
2000  candles  per  sq.  mm. 

An   interesting   demonstration   of   this 


1800 


^2 


1600 


if) 

Ld 

Z 
H 
X 

y; 

rx 

m 


1400 


1200 


1000 


800 


0.4  0.8  1.2    '■ 

POSITIVE  PROTRUSION- INCHES 


1.6 


FIG.  6  (left):  Effect 
of  positive  protrusion 
on  brightness  of  13.6- 
mm,  "290-ampere"  and 
super  high-intensity 
ij  projector  carbons. 

FIG.  7  (right):  Effect 
of  positive  protrusion 
on  current  capacity  of 
13.6-mm,  "290-amp- 
ere" and  super  high- 
intensity  projector  car- 
av      bons. 


£320 


0.4  0.8  1.2  1.6 

POSITIVE  PROTRUSION- INCHES 


14 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


2000 

/« 

■ 

1600 

•  . 

/  * 

•/• 

1200 

800 

400 

n 

2000 


FIG.  8   (left):   Brightness 

variation     with     current     en 

density   for  "high-bright-     ^ 

ness"  carbons. 


FIG.    9    (right):    Bright- 
ness variation  with  con- 
sumption rate  for  "high- 
brightness"   carbons. 


a:  1600 

UJ 

0- 


< 
O 
i 
U) 

<n 

UJ 


1200 


800 


x 

a: 
m 


5  400 

1 
x 

< 
S 


»        >» « 

«  »■/» 

%-t^ 

V . 

*    J 

i  l_x 

r  » 

i 


I  2  3 

CURRENT  DENSITY- AMPERES  PER  MM2 


0  40  80  120 

CONSUMPTION  RATE- INCHES  PER  HOUR 


160 


fact  is  given  by  a  comparison  of  the  two 
following  figures.  Fig.  4  shows  the  rela- 
tionship between  crater  brightness  and 
arc  current  for  a  new  higher-current  13.6- 
mm  carbon  when  operated  first  in  water- 
cooled  jaws  at  V^-inch  protrusion,  and 
then  in  conventional  air-cooled  jaws  at 
l^-inch  protrusion. 

The  outstanding  feature  of  the  water- 
cooling,  combined  with  the  shorter  pro- 
trusion which  this  makes  possible,  is  the 
ability  to  carry  much  higher  currents 
than  with  air  cooling,  and  to  attain  higher 
brightness  as  a  result.  Within  the  limits 
of  satisfactory  air-cooled  operation,  how- 
ever, the  carbon  reaches  a  higher  bright- 
ness at  a  given  current  than  when  water- 
cooled,  so  that  the  current  efficiency  of 
the  carbon  is  reduced  by  water-cooling. 

Not  Common  to  All  Carbons 

The  ability  to  carry  higher  currents 
with  water-cooling  is  not  characteristic  of 
all  carbons  however.  To  illustrate  this 
the  performance  of  the  13.6-mm  super 
high-intensity  projector  carbon,  repre- 
sentative of  the  usual  type  of  carbon,  is 
shown  in  Fig.  5.  Here  water-cooling  in 
no  case  produces  a  higher  brightness  than 
can  be  obtained  with  air-cooling,  and  the 
current  efficiency  is  always  less.  Thus 
with  this,  as  with  most  conventional 
types  of  carbons,  water-cooling  has  no 
such  advantage  in  increasing  brightness 
as  is  exhibited  by  the  "high-brightness" 
carbon  of  Fig.  4. 

Referring  again  to  Figs.  4  and  5,  it  will 
be  noticed  that  sharp  breaks  occur  in 
three  of  the  four  curves  in  the  two  fig- 
ures at  the  points  indicated  by  the  ver- 
tical arrows.  These  are  the  currents  at 
which  the  carbon  "overloads,"  with  the 
accompanying  hissing  and  sputtering 
which  is  familiaily  encountered  in  such 
cases.     At   higher   currents,   the   arc   is 


noisy  and  generally  unsteady,  prohibit- 
ing operation  under  practical  conditions. 
It  is  the  practice,  of  course,  to  operate 
a  carbon  at  a  current  somewhat  below 
this  "maximum"  value  at  which  overload 
occurs.  The  13.6-mm  super  high-inten- 
sity projector  carbon,  for  example,  over- 
loads at  about  176  amperes,  whether 
water-  or  air-cooled,  so  that  170  am- 
peres is  the  recommended  maximum  op- 
erating current  for  this  carbon.  The 
high-brightness  carbon  (Fig.  4)  reaches 
a  similar  overload  condition  at  282  am- 
peres when  air-cooled. 

Varying  Characteristics  of  Carbons 

However,  in  interesting  contrast  to  the 
usual  types  of  overload,  this  carbon  does 
not  behave  in  the  manner  just  described 
when  water-cooled,  even  at  currents  up 
to  500  amperes.  It  operates  quietly  up 
to  about  325  amperes.  At  higher  cur- 
rents, the  light  remains  steady,  but  a 
sort  of  droning  noise  gradually  develops, 
which  is  altogether  different  in  quality 
and  much  lower  in  intensity  than  with 
the  conventional  type  of  overload,  and 
quite  tolerable  in  many  applications. 

We  have  found  this  clear-cut  difference 
to  exist  to  the  extent  described  only  with 
carbons  having  relatively  thin  shells  (less 
than  2  mm  thick  with  the  13.6-mm  car- 
bon). High-brightness  carbons  having 
thicker  shells  (of  which  the  13.6-mm, 
"290-ampere"  carbon  is  an  example)  ex- 
hibit tendencies  toward  the  hissing  type 
of  overload  common  to  usual  types  of 
carbons,  so  that  their  "maximum"  cur- 
rent is  fairly  well  defined. 

Another  manifestation  of  the  unique 
properties  of  the  high-brightness  type 
of  carbon  is  the  relation  of  brightness 
and  of  arc  current  to  positive  protru- 
sion. Figs.  6  and  7  show  these  relation- 
ships for  the  290-ampere,    13.6-mm  car- 


bon. As  the  protrusion  is  lessened  to 
give  improved  crater  cooling,  the  "maxi- 
mum" current  and  the  brightness  in- 
crease. The  usual  type  of  carbon,  exem- 
plified again  by  the  13.6-mm,  super  high- 
intensity  positive  carbon,  exhibits  little 
or  no  change  in  brightness  and  "maxi- 
mum" current  with  change  in  protru- 
sion. 

High  brightnesses  have  been  obtained 
with  these  special  carbons  at  significantly 
higher  current  and  carbon  efficiencies 
than  have  been  reported  by  other  investi- 
gators. For  instance,  the  maximum  per- 
formance predicted  by  Hallet2  is  exceed- 
ed by  all  of  the  15  high-brightness  car- 
bons for  which  the  data  are  plotted  on 
Fig.  8.  These  carbons  are  from  9-  to  13.6 
mm  in  diameter  and  exceed  the  predicted 
performance  at  a  given  current  density 
by  as  much  as  10%,  although  the  gen- 
eral shape  of  Hallet's  master  curve  is  fol- 
lowed quite  well. 

Another  interesting  property  of  these 
carbons  is  their  ability  to  produce  a  much 
higher  brightness  at  a  given  consump- 
tion rate  than  was  characteristic  of  the 
carbons  which  Finkelnburg1  examined 
in  Germany.  Data  on  many  of  our  high- 
brightness  carbons  ranging  in  size  from 
9-  to  16-mm  and  burned  in  water-cooled 
jaws  are  plotted  on  Fig.  9.  The  bright- 
ness at  a  given  consumption  rate  exceeds 
that  reported  by  Finkelnburg  by  more 
than  50%  in  all  cases. 

Discontinue   Berryllium   in   Lamps 

Effective  June  30,  major  manufacturers  of 
fluorescent  lights  will  stop  using  berryllium 
phosphor,  which  has  been  established  as  a 
menace  to  health  even  if  only  inhaled,  much 
less  introduced  into  a  body  wound.  G.  E., 
Westinghouse  and  Sylvania  lead  the  way, 
with  other  manufacturers  expected  to  follow 
suit   shortly. 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


15 


IN  THE 


LIGHT 


By 

HARRY 

SHERMAN 


DEATH  claimed  two  outstanding  per- 
sonalities within  the  IA  during  the 
past  month  when  William  C.  Elliott,  for- 
mer international  president,  and  Louis 
Krouse,  who  upon  his  retirement  in  1945 
was  general  secretary-treasurer,  were 
stricken  fatally  within  four  days  of  each 
other — Elliott  on  June  15,  and  Krouse  on 
June  19. 

Bill  Elliott  joined  Cincinnati  Local  5 
in  1902  and  early  displayed  a  liking  for 
road  shows,  probably  the  most  noted  of 
which  were  the  Maude  Adams  tours 
which  he  served  for  a  considerable  time 
as  an  electrician.  Bill  was  a  stagehand 
from  his  finger  tips  to  his  toes,  and  he 
often  asserted  that  the  typical  stage  crew 
could  "build  anything  anywhere — often 
with  little  or  nothing — and  make  it  serve 
its  intended  purpose." 

Bill's  rise  in  the  Alliance  was  as  speedy 
as  some  of  his  road  jumps  were  long, 
for  after  first  being  named  a  delegate 
to  the  Cincinnati  Convention  of  1922,  he 
was  selected  by  the  general  executive 
board  to  be  5th  IA  vice-president  to  suc- 
ceed Ed  Tinney,  who  resigned  in  1923 
to  take  the  post  of  IA  representative. 

Eight  years  later — on  December  9, 
1931 — International  President  William 
F.  Canavan  resigned  from  office  and  Bill 
Elliott  was  named  by  the  Board  to  suc- 
ceed him.  These  depression  years  were 
productive  of  considerable  unrest,  and  in 
some  instances  actual  strife,  within  la- 
bor's ranks,  and  Elliott  was  handed  more 
than  his  share  in  both  the  production 
and  exhibition  branches  of  the  industry. 
His  term  of  office  also  witnessed  the 
adoption  and  the  first  fumbling  opera- 
tions of  the  National  Recovery  Act — the 
famed  NRA — and  this  added  no  little  to 
Bill's   burden. 

He  carried  the  ball  and  absorbed  the 
inevitable  pounding  which  is  the  lot  of  a 
man  in  such  a  position  until  the  Louis- 
ville Convention  of  1934,  when  he  re- 
signed to  return  to  his  former  post  as 
business  manager  of  Cincinnati  Local  5. 
He  held  the  latter  office  all  through  the 
intervening  years  and  attended  every  IA 
Convention  in  the  interim. 

Bill's  genial  disposition  and  open- 
hearted  frankness  won  him  a  host  of 
friends  within  and  without  the  Alliance, 
and  the  record  shows  tha*  he  faced  up  to 


many  tough  situations  with  courage  and 
determination.  His  absence  from  the  next 
IA  Convention  will  be  marked  by  many 
of  his  fellow  workers,  and  that's  about 
the  best  recommendation  any  man  can 
have.  He  is  survived  by  his  widow  and  a 
daughter. 

Although  Louis  Krouse  is  more  widely 
remembered  for  his  association  with  the 
IA  general  office,  the  real  old-timers  will 
recall  him  as  the  fledgling  delegate  to 
the  Seattle  Convention  in  1913  who  spon- 
sored the  famous  Resolution  No.  9  which 
paved  the  way  for  the  granting  of  full 
charters  to  projectionist  locals. 

In  1909  Krouse  represented  the  Mov- 
ing Picture  Operators  Auxiliary  of  Phila- 
delphia Local  37.  In  1913  he  was  named 
a  convention  delegate,  and  it  was  at 
Seattle  that  he  obtained  unanimous  ap- 
proval for  the  resolution  which  conferred 
separate  charters  and  full  autonomy  to 
operators'  locals,  the  forerunner  of  all 
such  charters.  His  own  Local  was  No. 
3.07,  Philadelphia. 

Lou  never  missed  an  IA  Convention 
from  1913  down  to  1944,  when  he  was 
incapacitated  by  the  illness  which  he  en- 
dured until  his  death  on  June  19  last. 
At  Cleveland  in  1917  he  was  elected  5th 
IA  vice-president,  a  post  which  he  re- 
signed after  a  few  months  when  he  was 
named  an  international  representative  by 
President  Charlie  Shay.  Lou  remained 
a  representative  for  15  years  until  1932, 
when  he  was  appointed  assistant  inter- 
national president  by  President  William 
C.  Elliott.  He  succeeded  the  late  Fred 
J.  Dempsey  as  general  secretary-treas- 
urer, which  office  he  held  until  his  re- 
tirement in  1945. 

Lou  was  an  organizational  workhorse, 
and  during  his  28  consecutive  years  of 
IA  service  witnessed  the  influx  of  more 
locals  and  new  members  into  the  Alliance 
than  any  other  national  officer.  One  of 
his  outstanding  jobs  was  as  coordinator 
of  the  NRA  Motion  Picture  Code. 

Lou's  funeral  was  attended  by  many 
officers  and  members  of  the  general  office 
and  the  various  locals.  He  is  survived  by 
his  wife,  Ida,  and  two  sons,  Morton  and 
Theodore,  the  latter  a  medical  doctor 
who  is  also  a  member  of  Local  307. 


•  Detroit,  Mich,  was  the  scene  of  the 
recent  two-day  meeting  of  District  No.  8. 
Don  Barneclo,  business  agent  of  Indian- 
apolis Local  30,  was  elected  District 
secretary,  succeeding  Arthur  Lyday, 
business  agent  of  Indianapolis  Local  194, 
who  retired  after  holding  the  office  for 
about  20  years.  Harland  Holmden,  1st 
IA  vice-president  and  business  agent  of 
Cleveland  Local  160,  presided. 

Among  the  IA  officials  attending  the 
meeting  were  John  B.  Fitzgerald,  inter- 
national representative  and  member  of 
Cleveland  Local  27;  Roger  B.  Kennedy, 
5th  vice-president  and  business  agent  of 
Detroit  Local  199,  and  the  late  William 
C.  Elliott,  past  IA  president  and,  at  the 
time  of  his  recent  death,  business  agent 
of  Cincinnati  Local  5. 

•  We  were  extremely  interested  in  an 
item  appearing  in  the  labor  press  rela- 
tive to  the  employer-financed  old  age 
pension  plan  of  the  ILGWU  (Interna- 
tional Ladies  Garment  Workers  Union) 
which  has  a  membership  of  85,000.  This 
plan,  effective  June  1  last,  assures  each 
member  a  lifetime  pension  of  $65  per 
month. 

We  should  like  to  compare  this  with 
the  retirement  fund  of  Chicago  Local  110, 
with  a  membership  of  about  700,  which 
provides  each  member  with  a  lifetime 
pension  of  $100  per  month,  plus  addi- 
tional benefits.  A  five-year  pact  between 
Local  110  and  the  exhibitors,  effective 
September  1,  1948  (see  IP  for  Aug.  1948, 
p.  17;  Feb.  1949,  p.  19),  providing  for 
a  welfare  fund  for  the  union  member- 
ship, was  hailed  throughout  the  Alliance 
as  the  forerunner  of  a  new  trend  in 
theatrical  employer-labor  relations.  Gene 
Atkinson,  business  manager  for  the  Chi- 
cago Local,  has  once  again  paved  the 
way  for  beneficial  agreements  between 
other  IA  Locals  and  exhibitors. 

•  Bert  Penzien,  for  many  years  business 
agent  of  Local  735,  Mt.  Clemens,  Mich., 
resigned  from  office  to  devote  more  time 
to  his  new  television  venture. 

•  New  England  District  No.  3  held  its 
annual  meeting  last  month  at  th;*  Hotel 
Bradford  in  Boston.  The  assembly  was 
addressed  by  IA  President  Walsh,  Gen- 
eral Secretary-Treasurer  Raoul,  and  As- 


16 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


sistant  President  Shea,  who  spoke  on 
matters  pertaining  to  the  industry  at 
large.  The  convention  endorsed  the  re- 
appointment of  Benjamin  G.  Hull,  mem- 
ber of  Springfield  Local  186,  as  associate 
commissioner  of  labor  in  Massachusetts. 
William  C.  Scanlan,  IA  trustee  and 
secretary-business  agent  of  Lynn  Local 
73,  presided  at  the  conclave,  replacing 
James  J.  Brennan,  4th  IA  vice-president, 
who  was  scheduled  to  preside  but  was 
hospitalized  at  the  time.  Brennan  has 
since  left  the  hospital  and  is  now  re- 
cuperating. 

•  A  scallion  to  the  source  who  sent  us 
the  item  last  month  erroneously  stating 
that  Grant  Johnson,  who  presented  Dick 
Green  with  a  gold  life  membership  card 
in  Chicago  Local  2,  was  president  of  the 
Local.  How  this  error  slipped  through 
is  beyond  our  understanding,  for  the 
president  of  Local  2  for  the  past  five  or 
six  years  is  Bill  Oke,  a  very  good  friend 
of  ours. 

•  Joe  Davis,  member  of  New  York  Local 
306  and  past  president  of  the  Theatrical 
Square  Club,  is  spending  his  vacation 
visiting  the  various  studios  on  the  West 
Coast. 

•  Local  178,  Salisbury,  N.  C.  is  mighty 
proud  of  its  president  and  former  busi- 
ness agent,  Marshall  Ramsey,  who  was 
recently  elected  to  the  city  council.  Mar- 
shall is  also  secretary  of  the  North  Caro- 
lina State  Federation  of  Labor  and  of 
the  State  Council  of  IA  Locals.    James 


B.  Mahaley  was  elected  business  agent 
of  the  Local,  succeeding  Marshall. 

•  A  recent  note  from  C.  Mills,  secre- 
tary of  Local  105,  London,  Canada,  ad- 
vised us  of  the  death  of  George  (Newt) 
Wallis,  former  president  of  the  Local. 
Last  month  we  reported  that  Newt  had 
suffered  a  relapse  while  apparently  re- 
covering from  a  serious  operation.  Serv- 
ices held  in  St.  Thomas  Church  were 
conducted  by  the  Rev.  J.  Fleck,  assisted 
by  the  Local's  vice-president,  T.  Robert- 
son. Worshipful  Master  of  Lodge  No.  44, 
A.  F.  &  A.  M. 

•  The  meeting  of  the  Tri-State  Associa- 
tion held  in  Fairmont,  W.  Va.  last  month 
was  the  occasion  of  a  dual  celebration: 
the  Tri-State  organization  observed  its 
25th  anniversary,  while  Fairmont  Local 
239  celebrated  its  37th.  A  record  attend- 
ance marked  this  convention,  with  more 
than  125  representatives  and  guests  from 
the  35  member  locals  being  present. 
President  Walsh,  General  Secretary- 
Treasurer  Raoul,  and  Assistant  President 
Shea  were  among  the  IA  executives 
present. 

F.  P.  McCoy,  secretary  of  New  Ken- 
sington Local  444,  was  re-elected  secre- 
tary of  the  Association.  Erie,  Penna.  was 
chosen  as  the  site  for  the  1950  meeting. 

•  The  brothers  Storch,  Nat  and  Albert 
(Skippy),  members  of  Local  366,  West- 
chester Co.,  N.  Y.,  are  spending  their 
vacations  cruising  in  South  American 
waters.    Nat,    who    is    president    of    the 


NAMED    BRONX    SCHOOL    BOARD    MEMBER 


CHICAGO    LOCAL    110    PRESENTS    FIRE    HEROINE    WITH    MOVIE    PROJECTOR    AND    FILM 


Fully  recovered  from  the  serious  burns  sustained  when  she  heroically  risked  her  life  to  save 
those  of  her  brothers  and  sisters  from  a  fire  which  destroyed  the  shack  in  which  they  lived, 
Roberta  Lee  Mason  views  the  film  record  of  the  building  of  a  new  $17,500  'Dream  House'  built 
by  the  people  of  Chicago  through  the  combined  efforts  of  all  building  trade  unions. 

IA  Local  110's  contribution  to  the  project,  in  accordance  with  a  promise  made  by  Gene 
Atkinson,  business  '•manager,  was  a  complete  film  record  of  construction  activities  and  a  com- 
plete sound  projection  equipment.  Shown  here  at  film's  preview  are  (seated)  Miss  Mason  and 
Dr.  Karl  Meyer,  Cook  County  Hospital,  and  (standing)  Gene  Atkinson,  Dr.  Ole  Nelson,  of  the 
hospital  staff,  and  Fred  Hertwig,  hospital  warden.  Prints  of  the  film  will  be  shown  in  the 
Chicago  schools  and  at  union  meetings. 


Morris  J.  Rotker,  member  of  New  York  Local 
306,  was  recently  sworn-in  by  Borough  Presi- 
dent Lyons  (left)  as  a  member  of  Local 
School  Board  18,  Bronx,  N.  Y.  Rotker  has  been 
a  member  of  306  since  1914,  has  held  many 
offices  in  the  Local,  and  is  a  past  president  of 
the  25-30  Club.  He  recently  celebrated  his 
35th  wedding  anniversary. 

Local,  was  electrician  for  the  popular 
musical  "High  Button  Shoes,"  which  re- 
cently closed  a  successful  Broadway  run. 
Skippy  is  soundman  with  the  stage  hit 
"Mr.  Roberts." 

•  R.  E.  (Rut)  Morris,  secretary-busi- 
ness agent  of  Local  142,  Mobile,  Ala., 
was  re-elected  secretary  of  the  7th  Dis- 
trict at  the  recent  annual  convention. 
The  meeting,  held  in  Chattanooga,  Tenn., 
was  attended  by  top  IA  officials. 

•  Morris  J.  Kravitz,  business  agent  of 
New  York  Local  306  since  1942,  died 
last  month  several  hours  after  he  col- 
lapsed on  the  street.  Morris  was  stricken 
with  partial  paralysis  several  years  ago, 
but  despite  his  physical  handicap  he 
continued  with  his  official  duties. 

Steve  DTnzillo,  who  pinch-hit  for 
Kravitz  when  the  latter  was  first  stricken, 
was  appointed  temporary  business  agent 
by  Herman  Gelber,  306  president. 

•  Recent  out-of-town  visitors  to  the 
offices  of  IP:  Gene  Atkinson  and  Clar- 
ence Jalas,  business  manager  and  secre- 
tary, respectively,  of  Chicago  Local  110; 
Father  Robert  A.  Boelcke,  head  of  the 
science  department  of  St.  Mary's  College, 
North  East,  Penna.;  Jake  Pries,  business 
agent,  Atlanta  Local  225;  Jack  Behlke, 
field  man  for  Motiograph;  John  Shuff, 
business  agent,  Local  364,  Akron,  Ohio, 
Paul  Baron,  Local  302,  Calgary,  Canada, 
and  Herbert  Schell,  secretary-business 
agent  of  Local  12,  Columbus,  Ohio. 

•  Mississippi's  "blue-law"  banning  Sun- 
day movies  received  a  setback  recently 
when  despite  the  arrests  of  22  theatre 
employes — managers,  ticket-takers,  cash- 
iers and  projectionists — the  show  still 
went  on.  Substitute  projectionists  took 
over  when  the  regular  men  were  booked 
on  charges. 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


17 


Direct  Fight   Pickup    Proves    Theatre    Tv    Feasibility 


THEATRE-Tv  proponents  made  with 
the  chest-puffing  and  cock-crowing 
following  the  recent  direct  pickup  of  the 
Walcott-Charles  heavyweight  fight  in  Chi- 
cago for  showing  on  the  screens  of  the 
Paramount,  Times  Square,  and  the  Fox, 
Brooklyn,  theatres.  The  latter  utilized 
the  RCA  instantaneous  projection  equip- 
ment to  produce  a  15  x  20-foot  image, 
while  the  Paramount  employed  its  own 
intermediate  film-storage  system  in  which 
the  Tv  image  is  photographed  on  film, 
developed  and  projected  via  the  regular 
theatre  equipment  within  a  minute. 

The  Fox  played  to  SRO,  with  4500 
tickets  being  sold  for  a  4060-seater,  and 
announcement  being  made  that  the  house 
could  have  been  sold  out  twice  over. 
The  Paramount  failed  to  sell  out,  despite 
the  proximity  of  the  Times  Square  fight 
mob  who  were  expected  to  pack  the 
house.  Both  theatres  added  the  fight  to 
their  regular  programs  at  no  advance 
in  price. 

Events  at  the  Fox  showing  are  of  par- 
ticular interest  to  projectionists.  The 
Tv  projector  was  installed  in  the  loge, 
as  was  the  control  unit,  although  the 
latter  would  have  gone  into  the  projec- 
tion room  if  the  run  of  coaxial  cable  had 
been  long  enough. 

IA  Men  Install,  Run  Show 

Installation  of  the  Tv  units  was  made 
jointly  by  members  of  IA  Stagehands 
Local  4  (Brooklyn)  and  RCA  engin- 
eers, in  addition  to  standby  projectionist 
members  of  Local  306  (N.  Y.  City). 
Standby  time  was  split  up  as  follows: 
one  man  for  13  hours  and  a  two-man 
crew   for   11   additional  hours. 

Actual  operation  of  both  the  Tv  pro- 
jector and  the  control  unit  was  handled 
by  the  regular  theatre  projection  crew  of 
two  men.  Joe  Lieberson,  RCA  engineer 
in  charge  of  the  installation  and  opera- 
tion of  the  equipment  (also  a  member  of 
Local  306)  stated  that  "everything  went 
off  perfectly."  RCA  officials  present  at 
the  showing  are  credited  with  the  state- 
ment that  the  same  policy  with  respect 
to  the  use  of  IA  men — stagehands  and 
projectionists — will  be  followed  wher- 
ever similar  showings  are  given. 

The  equipment  used  at  the  Fox  utilized 
a  20-inch  mirror  and  a  lS^-inch  plastic 
lens  having  a  combined  weight  of  only 
50   pounds   as  contrasted  with   the   500- 


pounds  weight  of  the  optical  system 
used  last  year.  A  smaller  optical  barrel, 
only  30  inches  in  diameter  and  36  inches 
long,  is  now  the  only  equipment  re- 
quired in  the  theatre  auditorium,  and 
for  a  15  x  20-foot  screen  image  this 
barrel  may  be  mounted  40  to  65  feet 
from  the  screen. 

Harry  Garfman,  Brooklyn  business 
representative  for  Local  306,  really 
merited  the  kudos  he  received  for  his 
smart  handling  of  this  situation. 

Theatre  Tv  has  proved  its  complete 
feasibility  technically;  but  there  still  re- 
mains the  question  of  programming  in 
terms  of  how  many  special  events  with 
the  "pull"  of  the  Walcott-Charles  fight 
are  available  through  the  year — particu- 
larly when  such  events  are  as  overflow- 
ing cream  for  the  pudding  of  the  regu- 
lar theatre  film  program. 


TOA  to  Act  on  Theatre  Tv 

Agreement  has  been  reached  between 
the  theatre  Tv  committees  of  the  SMPE 
and  the  Theatre  Owners  of  America  that 
if  exclusive  Tv  programs  are  to  be  sent 
by  radio  the  motion  picture  industry 
must  prove  its  radio  channel  needs  to 
the  FCC  within  the  next  three  to  five 
months.  Exhibitors  may  ultimately  pro- 
vide their  own  radio  facilities  or  buy 
service  from  a  common  carrier,  but  either 
way  FCC  approval  and  channel  alloca- 
tion is  required. 

Engineers  speculate  that  the  forthcom- 
ing allocation  of  new  Tv  channels  will 
force  broadcasters  and  other  services  to 
request  additional  channels  which  are 
now  earmarked  for  experimental  theatre 
Tv.  Time  for  the  decision  on  radio  vs. 
cable  distribution  of  theatre  Tv  programs 
is  running  out  because  others  will  soon 
be  able  to  prove  their  need  for  this  air 
space.  Failure  to  convince  the  FCC  now 
will  leave  only  cable  for  distribution, 
which  may  prove  to  be  wholly  unecon- 
omical. 

Cost  Data  Imperative 

To  sound  out  comparative  costs  be- 
tween common  carrier  and  private  dis- 
tribution as  well  as  cable  vs.  radio,  TOA 
plans  to  confer  with  A.T.&.T.  on  inter- 
and  intra-city  program  exchange. 

Theatre  owners  who  have  experimented 
with  theatre  Tv  agree  that  cost  of  equip- 
ment, although  high  when  compared  to 


conventional  motion  picture  projectors, 
is  small  when  compared  to  the  cost  of 
Tv  programming.  Program  rights,  talent, 
studio  facilities  and  remote  pickup  are 
among  the  incidental  charges  that  must 
be  included. 

In  a  serious  attempt  to  develop  accu- 
rate cost  information  and  to  learn  just 
how  Tv  will  best  tie-in  with  motion  pic- 
ture theatre  entertainment,  a  group  of 
40  to  50  theatres  is  now  considering  the 
experimental  installation  of  Tv.  Further 
SMPE  and  TOA  meetings  will  be  held 
prior  to  the  convention  in  Los  Angeles 
in  September. 


Remote-Control  Tv  Brightness  Unit 

A  remote-control  attachment,  permitting 
the  Tv  viewer  to  control  the  brightness  and 
contrast  of  a  receiver  from  his  armchair 
or  other  locations  in  the  room,  is  incor- 
porated in  RCA's  newest  big-screen,  projec- 
tion-type Tv  receiver. 

The  remote-control  unit  is  contained  in  a 
small  wooden  box  which  can  be  connected 
with  the  receiver  by  a  25-foot  length  of 
wire  which  can  be  run  inconspicuously  under 
the  rug.  Dual  knobs  on  the  box  permit 
adjustment  of  screen  brightness  to  suit  the 
observer's  preference.  The  300-square-inch 
(15"  x  20")  screen  can  be  lowered  into  the 
cabinet  when  the  set  is  off. 


Biggest  Tv  Set  Sales  Inroads  Among 
Movies'  Prime  Patron  Group 

Families  in  the  middle  and  lower  in- 
come groups — backbone  of  the  movie 
audience — possess  58%  of  the  Tv  sets  in 
use  today,  according  to  the  results  of  a 
Sylvania  Electric  Products  survey.  It 
was  shown  that  the  rate  of  purchase  of 
families  making  less  than  $5,000  yearly 
is  mounting  much  faster  than  that  of 
those  taking  in  more  than  $5,000. 

Sylvania  reported  that  among  families 
making  less  than  $2,000  ownership  of 
Tv  sets  had  gone  up  50%  from  Decem- 
ber, 1948,  to  February,  1949,  the  increase 
being  33%  among  families  earning  up  to 
$5,000  and  30%  among  those  in  higher 
brackets. 

The  survey  was  made  during  the  last 
week  of  February  and  the  first  week  of 
March  in  13  cities  that  have  had  video 
available  for  different  lengths  of  time. 


Your  Best  Buy  .  .  . 

U.  S.  SAVINGS  BONDS 


18 


INTERNATIONAL  PROJECTIONIST 


JULY  194* 


IN  THE  irridescence  of  an  oil  film  on  a 
wet  city  pavement  and  in  the  colors  of 
a  soap  bubble  in  the  sunlight,  science 
and  industry  have  the  key  to  the  most 
precise  and  delicate  direct  measuring 
method  known. 

"It  has  been  observed  by  others,  that 
transparent  substances,  such  as  glass, 
water,  air,  etc.,  when  made  very  thin  by 
being  blown  into  plates,  do  exhibit  vari- 
ous colours,  according  to  their  various 
thinness,  although  at  a  greater  thickness 
they  appear  very  clear  and  colourless." 
So  wrote  Sir  Isaac  Newton  in  the  last 
quarter  of  the  17th  Century,  and  then  he 
sets  about  describing  a  series  of  experi- 
ments in  what  we  now  call  physical  optics 
which  have  not  been  surpassed  in  ingenu- 
ity to  date.  Considering  the  crudity  of 
his  apparatus,  the  accuracy  of  his  results 
is  amazing. 

Incredible  Precision  Required 

The  dimensioning  of  mechanical  parts 
for  high-grade  optical  apparatus  is  very 
precise.  For  instance,  the  lens  separa- 
tions in  a  modern  microscope  objective 
are  specified  in  thousandths  of  a  milli- 
meter, or  microns,  one  of  which  equals 
0.00004".  But  for  gauging  optical  sur- 
faces on  lenses,  prisms,  and  reflectors, 
the  micron,  small  as  it  is,  is  still  too 
large.  Here  recourse  must  be  taken  to 
fractions  of  the  wavelength  of  light. 

The  optical  engineer  assumes  and  the 
skilled  optical  craftsman  attains  in  rou- 
tine production  accuracies  of  curve  to 
0.000  006"  and  can  exceed  in  fineness 
0.000  000  8"  when  instrumental  applica- 
tions require. 

How  can  optical  work  be  measured 
confidently  with  such  delicacy?  "It's 
very  simple,"  says  the  experienced  lens 
grinder  and  polisher.  "I  measured  it  by 
Newton's  Rings  and  it's  within  a  quarter 
or  a  tenth  or  a  thirtieth  of  a  wave- 
length." In  the  color  phenomena  of  thin 
wedge  films  he  has  a  means  for  measur- 
ing the  accuracy  of  transmitting  and  re- 
flecting surfaces  in  units  which,  though 
real,  are  so  small  as  to  be  almost  incon- 
ceivable. 

Newton's  Pioneer  Calculations 

Each  time  such  a  measurement  is 
made,  the  classical  experiments  of  New- 
ton are  duplicated.  Newton  was  not  the 
first  to  observe  the  formation  of  colored 
areas  in  the  thin  film  of  air  between  two 
polished  plates,  or  in  thin  layers  of  water 
as  in  soap  bubbles,  or  thin  plates  of 
glass,  mica  or  pitch.  Nor  was  he  the  first 
to  propose  an  explanation.  Robert  Boyle 
and  Hooke,  the  microscopist,  both  pre- 
ceded him.  Neither  one,  however,  pro- 
vided an  explanation  on  a  definite  quan- 
titative basis. 

"To  observe  more  nicely  the  colours" 
under  controlled  conditions,  Newton 
placed  the  plane  surface  of  a  piano-con- 


Newton's  Rings: 

Yardsticks  of 
Optical  Science 


Scientific  Bureau 
Bausch  &  Lomb  Optical  Company 

Frequent  mention  of  the  term  "New- 
ton's Rings"  in  articles  anent  projec- 
tion optics  appearing  in  these  columns 
evoked  not  a  few  inquiries  from 
readers  as  to  the  meaning  of  this  ex- 
pression. This  article,  it  is  hoped, 
will  satisfy  this  interest. 


vex  objective  from  a  14-foot  telescope 
on  the  convex  surface  of  a  bi-convex  ob- 
jective from  a  telescope  of  about  50-foot 
focus,  thereby  forming  a  thin  film  of  air 
which  gradually  increased  in  thickness 
from  zero. 

Upon  observing  this  arrangement  by 
reflected  light,  at  the  center  where  the 
surfaces  were  in  contact  he  saw  a  black 
circular  spot  about  which  was  a  series 
of  bright  and  dark  concentric  circles.  In 
white  light  the  bright  rings  were  colored. 
In  red  light  the  rings  were  larger  than 
when  viewed  in  blue  light.  By  calculat- 
ing the  distance  between  the  glass  sur- 
faces he  was  able  to  determine  the  air 
film  thickness  responsible  for  each  color. 

Ingenious  as  was  Newton's  Corpuscu- 
lar Theory,  it  finally  lost  ground  in  the 
face  of  the  Wave  Theory  as  sponsored 
by  Huygens,  Young  and  Fresnel. 

The  modern  explanation  of  Newton's 
Rings  is  based  upon  the  assumption  that 
light  consists  of  periodic  disturbances 
which,  regardless  of  their  frequency, 
travel  at  the  same  speed  in  any  homoge- 
neous medium. 

It  can  be  visualized  somewhat  imper- 
fectly by  the  mechanical  analogy  of 
water  waves  which  would  be  formed  by 
touching  a  tuning  fork  or  vibrating  reed 
to  a  liquid  surface.  With  such  a  set-up 
ripples  would  radiate  in  all  directions 
from  the  point  of  contact. 

If  the  fork  was  of  low  note,  fewer 
waves  would  be  radiated  per  second  than 
if  a  higher  note  fork  were  used.  The  dis- 
tance between  the  crest  of  one  wave  to 
the  crest  of  the  next  would  be  the  wave- 
length in  either  case.    Obviously  the  low 


note  fork  would  produce  the  longer  wave. 
Using  two  forks  of  identical  vibration 
rate,  it  would  be  possible  to  find  a  posi- 
tion where  the  waves  from  one  fork 
would  dampen  out  or  nullify  the  waves 
from  the  other.  Another  position  could 
be  found  where  the  waves  from  one  fork 
would  accentuate  the  waves  from  the 
other.  In  the  first  case  the  waves  would 
be  out  of  step  or  phase.  In  the  second 
case  the  waves  would  be  in  step  or  phase. 

Formation  of  Newton's  Rings 

With  light  we  have  a  condition  some- 
what similar.  A  body  giving  out  visual 
light  radiates  energy  in  wave-form,  in 
v/hich  the  distance  from  crest  to  crest 
ranges  from  about  0.0004  to  0.0008  mm 
and  which  travels  at  the  rate  of  approxi- 
mately 300,000,000  meters  p.s.  in  air. 

It  should  be  noted  that  interference  of 
light  waves  emanating  from  different 
sources  has  not  been  demonstrated  ex- 
perimentally, possibly  due  to  the  ex- 
tremely high  frequency  making  synchro- 
nization very  unlikely.  However,  light 
waves  from  the  same  source  can  be  made 
to  interfere  under  certain  conditions,  one 
of  which  is  that  responsible  for  the  for- 
mation of  Newton's  Rings. 

Let  us  assume  that  we  have  the  same 
experimental  arrangement  as  set  up  by 
Newton,  namely  a  convex  surface  of  very 
long  radius  and  a  plane  surface  enclos- 
ing a  very  thin  film  of  air.  As  an  illumi- 
nant  we  will  use  a  source  radiating  light 
of  one  wavelength. 

On  looking  at  the  enclosed  air  film 
from  above  we  will  see  a  central  dark 
spot  surrounded  by  alternate  bright  and 
dark  circles.  If  we  looked  through  the 
air  film,  we  would  see  just  the  opposite, 
a  central  bright  round  area  surrounded 
by  alternate  dark  and  bright  circles. 

Path  of  Reflected  Rays 

Due  to  the  very  slight  difference  in 
curvature,  the  air  film  at  any  point  can 
be  considered  as  essentially  plane  par- 
allel. We  neglect  all  reflections  except 
those  at  the  enclosed  air  film-to-glass  sur- 
faces. These  conditions  are  diagrammed 
in  Fig.   1. 

A  portion  of  the  ray  of  light  coming 
(Continued  on  page  23) 


A 

B  \ 

Ai   \ 

\c/ 

\      /    GLASS 

V  D 

Alf\  FIL  M 

GLASS 

FIGURE    1 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


19 


Century  Projector  Develops  Water-Cooled  Aperture  Unit 


CHARACTERIZING  the  move  as  a 
"return  to  first  principles,"  Century 
Projector  Corp.  has  announced  the  avail- 
ability of  water-cooled  apertures  on  their 
Models  C  (single-shutter)  and  CC 
(double-shutter)  projectors  as  a  means 
for  overcoming  the  serious  effects  of  the 
ever-increasing  wattage  used  for  carbon 
arc  lamps.  Among  the  improvements 
effected  by  this  unit,  says  Century,  is  the 
elimination  of  film  buckle,  hot  film  trap 
shoes  and  sticking  film  emulsion  even  on 
new  green  prints. 

The  use  of  higher  arc  currents  with 
this  unit  is  held  by  Century  to  permit 
the  projection  of  full-brilliance  screen 
images  without  the  loss  of  light,  defini- 
tion or  of  wasted  power.  Century  avers 
emphatically  that  neither  forced  air  cool- 
ing nor  carbon  water-cooling  will  serve 
to  reduce  film  temperature  and  thus 
eliminate  distortion  caused  by  buckling. 

Details  of  Cooling  Setup 

Century  water-cooling  is  accomplished 
by  a  water  cell  placed  directly  in  back 
of  the  film  trap  through  which  flows 
approximately  %  pint  of  water  per 
minute.  If  water-cooling  is  also  used  in 
the  lamphouse  for  the  carbons,  the  same 
water  line  may  be  extended  to  the  aper- 
ture, thus  simplifying  the  installation. 

A  re-circulating  water  system,  to  be 
ready  shortly,  will  require  no  regular 
flow  of  water  and  will  be  fully  automatic 
in  operation. 

Standard  ^-inch  pipe  connections  are 
used;  also,  standard  %-inch  fittings  are 
provided  for  the  intake  and  outlet  of 
water  at  the  base  of  the  projector 
mechanism.  The  %-inch  pipe,  coupl- 
ings, reducing  fixtures,  rubber  hose,  at- 
tachments, etc.,  are  readily  available  at 
all  plumbing  supply  houses,  or  they  may 
be  obtained  through  Century. 

Century    Model     CC    projector     (light     shield 

removed)      showing      water-cooled      aperture, 

water    supply,    and    discharge    pipes. 


Wafer-Cooiod  Aperfure 


The  cost  of  the  Century  water-cooling 
unit  per  each  projector  is  $90  list,  bear- 
ing on  which  point  Century  asserts  the 
following  advantages  may  be  realized: 

Cite  Advantages  of  Cooling  Unit 

1.  The  new  high-intensity  and,  espe- 
cially, the  super-high  arcs  may  be 
used  without  the  need  for  glass  heat 
filters  or  blower  attachments. 

2.  Light  losses  of  upward  of  20%  are 
recovered. 

3.  Initial  investment  (lower-amperage 
lamps  and  auxiliary  units)  and  oper- 
ating costs  are  reduced  substantially, 
with  Century  asserting  that  the  same 
amount  of  screen  light  can  be  ob- 
tained with  the  water-cooled  aperture 
at  a  saving  of  more  than  $3000  an- 
nually per  two-projector  installation. 

Century  emphasizes  the  point  that 
while  the  water-cooling  unit  was  de- 
signed primarily  for  arc  amperages  rang- 
ing from  80  to  180  amperes,  it  may  be 
used  with  comparable  advantages  in  any 
arc  setup,  the  basic  principles  being 
applicable  under  any  circumstances. 


New  Improved  Magnets  for  Both 
Models  of  Peerless  Lamps 

Two  new  adjustable  arc  stabilizing 
magnets — for  the  high-current  Hy-Can- 
descent  lamp  and  for  the  Magnarc  model 
—have  been  announced  by  J.  E.  McAuley 
Mfg.  Co.,  manufacturers  of  Peerless  arc 
lamps.  Not  only  are  these  new  magnets 
now  standard  equipment  on  all  Magnarc 
and  Hy-Candescent  lamps,  but  McAuley 
urges  that  they  be  substituted  for  other 
magnets  now  used  on  all  Peerless  lamps. 

The  changeover  to  the  new  magnet  on 
either  type  lamp  is  a  very  simple  operar 
tion,  with  absolute  satisfaction  and 
greatly  improved  operation  indicated  as 
a  result  of  exhaustive  tests  conducted  by 
McAuley  over  a  long  period  of  time  both 
at  the  factory  and  in  the  theatre  fiejd. 

The  Magnarc  Adjustable  Magnet 

The  Magnarc  magnet  is  made  of  cast 
Alnico.  It  is  a  dpuble  bevel  end,  bar 
type.  It  is  adjustably  positioned,  well 
above  the  axis  of  the  carbons,  so  that  the 
entire    magnetic    flux    force    is    exerted 

IA     ELECTION 

LOCAL  NO.  285,  TROY,  N.  Y. 

Charles  H.  McCarthy,  pres.;  James  J. 
Kelly,  vice-pres.;  Earl  Cooney,  rec.-sec; 
Vincent  J.  Iannacito,  fin.-sec;  Jesse  Loh- 
man,  treas.;  George  L.  Nugent,  bus.  mgr.; 
Thomas  Norris,  sgt.-at-arms;  James  J.  Kelly, 
John  Ross,  Leland  Day,  trustees;  McCarthy, 
Cooney,  Nugent,  Lohman  and  Kelly,  exec, 
board. 


against  the  arc  crater  and  its  gasses,  with 
an  impressing  effect. 

Provision  is  made  so  that  the  magnet's 
flux  field  can  be  adjusted  in  directions 
parallel  to  the  positive  carbon  crater 
face  and  also  toward  or  away  from  the 
crater,  coaxial  with  the  carbons.  The 
method  of  mounting  also  permits  a  tip- 
ping adjustment,  in  a  horizontal  plane, 
and  hence  complete  control  of  the  burn- 
ing arc  characteristics  is  attained. 

The  Hy-Candescent  Magnet 

The  new  Hy-Candescent  magnet  pro- 
vides means  for  the  complete  control  of 
the  burning  characteristics  of  high-cur- 
rent, high-intensity  arcs,  and  assures  cor- 
rect orientation  of  the  several  types  of 
arc  flames  into  a  single  coalesced  tail 
flame,  promoting  thereby  a  higher  ratio 
of  light  lumen  per  arc  watt  of  current 
across  the  arc. 

It  also  makes  possible  absolute  control 
of  the  sweeping  upward  angle  of  emana- 
tion of  the  positive  tail  flame,  and  this 
coaxial  with,  and  crossaxial  to,  the  axis 
of  the  positive  carbon. 

Detailed  specifications  anent  these 
units,  including  precise  drawings  and  in- 
stallation data,  are  available  from 
McAuley,  554  W.  Adams  St.,  Chicago  6. 


Larry  Davee  Named  Chairman  of 
SMPE  Projection  Committee 

L.  W.  (Larry)  Davee,  sales  manager  for 
Century  Projector  Corp.,  has  been  appointed 
chairman  of  the  SMPE  Projection  Practice 
Committee.  With  a  record  of  20  years 
membership  in  the  Society  and  active  par- 
ticipation in  many  of  its  engineering  com- 
mittees, Davee  is  expected  to  revitalize  the 


L.   W.   Davee, 
Chairman   of 
the  SMPE  Projec- 
tion    Practice 
Committee. 


Projection  Practice  Committee,  recent  ac- 
tivities of  which  have  been  on  a  somewhat 
restricted  basis. 

Foremost  on  the  list  of  projects  to  be 
undertaken  by  Davee's  committee,  following 
a  shakeup  of  personnel  to  effect  maximum 
effort,  is  a  revision  of  existing  projection 
room  plans  which  will  serve  as  a  model  for 
both  planning  new  rooms  and  modern- 
izing existing  structures.  Special  attention 
will  be  given  to  the  needs  of  both  direct 
and  film-storage  types  of  Tv.  Noteworthy 
will  be  the  preparation  of  recommended 
paragraphs  to  be  included  in  theatre  specs 
by  all  architects  and  theatre  builders. 
Standards  for  35-mm  projection  reels  will 
also  receive  major  attention. 

Intimately  identified  with  projectionists, 
Davee  is  an  honorary  life  member  of  the 
25-30  Club  of  N.  Y.  City. 


20 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


19,323  Theatres  Operating  in  U.  S. 

Theatres  operating  in  the  U.S.  as  of  Janu- 
ary 1  last  totaled  19,323,  according  to  the 
1949  edition  of  the  Film  Daily  Year  Book 
now  being  distributed.  On  the  same  date 
there  were  745  theatres  closed  "temporarily," 
thus  making  the  total  theatres  in  the  country 
20,068. 

Total  includes  983  Drive-In  theatres  and 
916  theatres  operated  principally  for  Negro 
patronage.  There  are  motion  picture  theatres 
in  10,087  U.  S.  cities  and  towns,  including 
175  places  where  films  are  shown  with  port- 
able projection  equipment. 

American  theatres  include  a  total  of  12,- 
071,311  seats,  of  which  11,722,616  are  in 
theatres  operating  as  of  Jan.  1,  and  348,695 
in  houses  not  operating  on  that  date. 

91,281    Theatres    Throughout    World 

Motion  picture  theatres  throughout  the 
world  totaled  91,281  as  of  Jan.  1,  according 
to  the  Year  Book.  Seating  capacities  of  the 
theatres  aggregated  39,067,196. 

Breakdown  of  world  theatres  shows,  in 
addition  to  20,068  in  the  United  States,  54,- 
071  in  Europe;  6386  in  Central  and  South 
America;  2900  in  the  Far  East;  2183  in  the 
South  Pacific;  1862  in  the  Middle  East; 
1207  in  Africa;  659  in  the  Caribbean  area; 
122  in  the  Atlantic  Islands;  1693  in  Canada, 
and  130  in  Puerto  Rico. 


SMPE   N.  Y.-Chicago  Joint  Tv  Meet 

The  first  joint  meeting  by  Tv  of  a 
technical  society  was  staged  by  the 
SMPE  on  June  28  when  the  Atlantic 
Coast  Section  program  held  at  the  Adel- 
phia  Theatre  in  New  York  was  broad- 
cast over  five  DuMont  affiliated  Tv  sta- 
tions including  WENR-Tv  Chicago, 
where  it  was  viewed  by  the  Mid-West 
Section.  More  than  600  attended  the 
New  York  meeting,  while  the  Chicago 
turnout  exceeded  500. 

Topic  of  the  hour-long  program  was 
lighting  methods  for  Tv,  the  time  being 
split  about  equally  between  "live"  and 
sound-film  fare.  Chicago  reported  ex- 
cellent reception. 


I.  Nixon,  B.  &  L.  Executive,  Dies 

Ivan  L.  Nixon,  66,  associated  with  Bausch 
&  Lomb  Optical  Co.  for  more  than  40  years, 
died  on  June  25  after  a  brief  illness.  At 
the  time  of  his  death  he  was  vice-president 
of  B.  &  L.  in  charge  of  the  Scientific  Instru- 
ment Division.  He  contributed  materially 
to  the  development  of  many  types  of  scien- 
tific instruments,  including  Balopticons,  pho- 
tomicrographic  and  metallographic  equip- 
ment, contour  measuring  projectors,  and 
motion  picture  camera  and  projection  lenses. 

During  World  "War  II  Mr.  Nixon  handled 
most  of  B.  &  L.'s  military  contracts  for 
optical  gunfire  control  equipment. 


Technicolor  1948  Profits  Up  Sharply 

Technicolor  set  new  high  marks  in  total 
sales  and  in  profits  during  1948.  Sales  hit 
$20,016,066  and  net  profit  was  $1,775,834, 
equal  to  $1.93  per  share.  Company's  expan- 
sion program  designed  to  double  annual 
capacity  to  320  million  feet  permits  the  de- 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


SXilPMTi: 


'  SEALED 
LENS  ELEMENTS 


ONE-PIECE 
MOUNT 


ANODIZED 
FINISH 


COATED 
'  OPTICS 


m* 


&% 


& 


»* 


& 


HOW  IS  IT  POSSIBLE  TO  GET  A  BLURRED  PICTURE  WITH 
A  GOOD  LENS? 

This  is  usually  caused  either  by  misalignment  of  the 
entire  optical  system  of  the  projector  or  by  the  lens 
not  being  securely  held. 

MUST  FAST  LENSES  BE  ALIGNED  MORE  ACCURATELY 
THAN  SLOWER  ONES? 

Yes.  An  extremely  fast  lens  such  as  the  Super-Snaplite, 
must  be  held  securely  at  all  times.  The  lamp,  projector 
and  lens  must  be  kept  in  alignment.  Check  by  inter- 
changing lenses  between  projectors. 

HOW  OFTEN  SHOULD  FOCUS  BE  CHECKED? 

For  perfect  projection  the  focus  should  be  checked  at 
frequent  intervals,  especially  after  reels  are  changed. 
If,  after  checking  focus,  alignment  and  lens  holder,  the 
lenses  do  not  give  a  good  picture,  they  should  be 
returned  for  inspection. 

HOW  SHOULD  COATED  LENSES  BE  CLEANED? 

Instructions  on  the  care  of  coated  and  uncoated  lenses 
are  shown  on  the  inside  cover  of  the  new  display  lens 
box  in  which  all  Series  II  and  Super-Snaplites  are 
shipped.  Additional  copies  may  be  obtained  by  writ- 
ing us.    Ask  for  Form  66. 

SHOULD  LENSES   BE  REPLACED   IN   LENS   HOLDERS  LN 
THE   SAME  POSITION  EVERY  TIME? 

This  is  not  necessary  since  all  Snaplite  lenses 
I  are  so  perfectly  centered  that  no  alignment 
'   marks  are  necessary. 


"You  Get  the  Most  Uniform  Light  with  Super-Snaplite' 

KOIJ,AtOKtfrfkV     / 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


livery  of  final  prints  within  five  months,  on 
the  average,  from  date  of  photography. 

During  1948  a  record  38  features  were 
shot  in  Technicolor,  plus  9  in  Britain.  At 
present  42  features  are  being  produced,  in 
addition  to  13  in  Britain. 


Millionth  Tv  Tube  Off  RCA  Line 

Indicating  that  the  time  when  Tv  and  the 
theatre  box-office  will  meet  head-on  for  the 
attention  of  the  entertainment-seeker  is  not 
too  far  in  the  future  is  the  announcement 
by  RCA  that  the  millionth  Tv  picture  tube 
came  off  the  production  line  last  month 
(June).  Figures  for  other  tube  manufac- 
turers have  not  been  announced. 


Nationalized  Movies  —  French  Style 

In  France  the  film  trade  is  semi-national- 
ized. With  the  craze  for  precise  classifica- 
tion that  afflicts  government  bodies,  an  offi- 
cial schedule  has  now  been  prepared  which 
sets  out  at  some  length  the  various  types  of 
damage  which  a  film  may  suffer,  reports  the 
Ideal  Kinema.  They  are  included  under  two 
headings:  defects  affecting  the  surface  and 
defects  of  the  perforations. 

The  former  are  divided  into  rubbing, 
scratching  and  melting:  a  fine  scratch  is 
defined  as  measuring  several  tenths  of  a 
mm,  while  a  wide  scratch  may  be  constituted 
by  a  number  of  fine  scratches.  The  scratch 
may  be  shallow  or  deep,  the  latter  when  the 
gelatine  has  been  completely  removed. 


The  scratch  may  be  continuous  or  inter- 
mittent; it  may  occur  in  the  margin  of  the 
picture,  at  the  sides  of  the  picture,  in  the 
centre  of  the  picture,  in  the  margins  of  the 
sound  track  or  in  the  track.  Melting  of  the 
gelatine  may  be  caused  either  by  drops  of 
water  or  of  heated  oil.  Perforations  may  be 
rubbed  by  the  projector  shoes,  picked,  em- 
bossed, torn  lengthwise,  or  across. 

Evidently,  if  a  projectionist  wishes  to  re- 
port film  damage  he  is  expected  to  examine 
the  film  through  a  microscope  and  to  specify 
precisely  the  damage  category. 


More  About  High  Tv  Voltages 

It  is  a  habit  of  the  human  being  gradu- 
ally to  become  contemptuous  of  anything 
with  which  he  becomes  familiar.  .  .  . 

It  is  said  time  and  again  that  the  high- 
voltage  units  in  Tv  receivers  will  not  kill  be- 
cause the  current  is  too  low;  but  we  have 
heard  of  numerous  instances  when  the  physi- 
cal damage  was  the  result  of  involuntary  mo- 
tion in  consequence  of  the  shock.  To  put 
it  simply,  men  have  been  injured  because 
they  jumped  when  shocked,  and  during  that 
moment  of  involuntary  activity  their  motions 
were  completely  out  of  control. 

Safety  interlocks  are  put  on  Tv  receivers 
for  a  definite  purpose  to  safeguard  life  and 
limb.  The  time  saved  by  "shorting"  the 
interlock  during  service  inspection  or  prob- 
ing of  the  receiver  is  too  little  to  warrant 
the  gamble  involved. 


Rubber  gloves  of  the  kind  which  will  with- 
stand high  voltages  should  be  a  must  in  Tv 
work.  Sleeves  should  be  rolled  down,  thus 
covering  the  skin  of  the  forearm.  Operating 
in  this  fashion  is  not  too  clumsy.  If  a 
surgeon  can  operate  with  gloves  on,  the 
serviceman  can  handle  tools  with  gloves  on. 
— John  F.  Rider  Manuals. 


Exchanges  Maintain  Fine  Safety  Mark 

A  record  of  three  successive  years  without 
suffering  any  loss  from  fire  has  been  turned 
in  by  the  400  exchanges  and  shipping  depots 
of  member  companies  of  the  Motion  Picture 
Association,  it  was  reported  by  John  B.  Mc- 
Cullough,  director  of  the  organization's  con- 
servation department. 

Over  the  last  23  years  there  were  only  16 
film  fires  in  member-operated  exchanges  in 
the  U.  S.,  for  an  average  annual  fire  loss  of 
only  $211.04. 


Double-Feature   Film    Bill   on   Tv 

Sponsors  having  deserted  the  Tv  networks 
in  droves  for  the  summer  season,  WJZ-Tv 
in  New  York  will  offer  a  two-hour,  double- 
feature  film  "bargain"  program  each  Tues- 
day night.  Evidently  the  double-feature  idea 
has  caught  up  with  Tv  rather  early.  Film 
to  be  used  was  produced  in  the  1940-45 
period,  which  is  considerably  later  than 
some  of  the  reissues  and  other  junk  now 
being  spilled  on  theatre  screens — with  no 
advance  warning. 


Giant  "Drive-In"  Images 

with 

Edge-to -Edge  Sharpness 


•  For  the  toughest  projection  job  .  .  . 

producing  clear,  critically  denned,  uniformly 

brilliant  giant  images  on  "Drive-In"  Theatre  screens 

.  .  .  Bausch  &  Lomb  Super  Cinephor  lenses  are 

preferred.  Only  screen  images  easy  to  look  at  with 

edge-to-edge  sharpness  satisfy  theatregoers.  Be  sure  your 

screen  images  are  the  best  .  .  .  specify  Bausch  &  Lomb 

Super  Cinephor  projection  lenses.  Bausch  &  Lomb  Optical 

Co.,  616-G,  St.  Paul  St.,  Rochester  2,  N.Y. 


FOR   TOP    IMAGE    QUALITY   ON   YOUR    SCREEN  ...  THE  W  TRADEMARK  ON   YOUR   LENS 


BAUSCH  &  LOMB 


PROJECTION  LENSES 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


NEWTON'S     RINGS 

(Continued  from  page  19) 
from  A  nearly  normal  to  the  film  is  re- 
fracted at  point  B,  where  it  leaves  the 
glass  on  entering  the  air  film  to  point  C 
where  it  is  reflected  back  through  the 
film  to  point  D,  where  it  is  refracted 
along  the  same  path  as  that  portion  of  a 
ray  coming  from  Al  is  reflected  at 
point  D. 

If  the  length  of  the  path  BCD  is  such 
that  the  light  waves  in  the  light  follow- 
ing the  path  BCD  are  out  of  step  one- 
half  wavelength,  they  will  interfere  with 
or  nullify  those  reflected  at  point  D,  and 
no  light  would  be  reflected  from  the  film. 

When  the  length  of  the  path  BCD  is 
such  that  the  refracted  and  reflected  por- 
tions are  in  step,  they  augment  each 
other  and  increased  reflection  occurs. 

It  would  seem  that  the  center  area, 
where  the  glass  surfaces  are  practically 
in  contact,  should  appear  bright  because 
here  the  film  thickness  is  very  small 
compared  with  the  wavelength,  and  suf- 
ficient lag  to  cause  interference  would 
not  occur.  The  apparent  discrepancy  is 
explained  as  follows: 

Reflection  at  C  occurs  in  air  and  there 
is  a  lag  in  the  reflected  light  of  one-half 
wavelength.    Reflection   at   D   occurs   in 


FIGURE  2 
Newton's    Rings    in    undeformed    surfaces. 

glass  with  no  retardation.  Accordingly, 
no  light  is  reflected  at  the  center  nor 
when  BCD  is  equal  to  any  whole  num- 
ber of  wavelengths. 

Taking  into  account  the  change  of 
phase  or  reflection  mentioned,  film  thick- 
nesses corresponding  to  odd  multiples  of 
one-quarter  wavelengths  will  give  in- 
creased reflection  or  "bright  rings,"  and 
those  corresponding  to  even  multiples 
will  give  decreased  reflection  or  "dark 
rings." 

Heretofore  we  have  considered  the 
conditions  for  light  of  only  one  wave- 
length. When  white  light  is  used,  the 
colors  seen  are  those  remaining  after 
interference.  It  is  interesting  that  light 
interferences     as     shown     in     Newton's 


Rings  also  forms  the  basis  of  surface 
treatment  of  lenses  to  prevent  a  loss  of 
light  by  reflection. 

From  the  foregoing  it  can  be  seen  that 
in  the  thickness  of  an  air  film  the  skilled 
optical  worker  has  a  means  of  extreme 
delicacy  and  accuracy  for  proving  his 
work.  It  is  surpassed  by  no  other  pre- 
cise physical  determination.  It  provides 
its  own  unchanging  standard. 

When  he  checks  his  work  by  simply 
noting  the  shape,  color,  and  number  of 
rings  or  bands  that  appear  when  he 
places  the  work  in  hand  in  contact  with 
the  master  gauge,  he  can  determine  dif- 
ferences in  curve  or  flatness  in  any  de- 


sired fraction  of  the  wavelength  of  the 
light  employed.  By  using  this  test  he 
can  arrive  at  such  perfection  of  surface 
that  molecular  cohesion  results  when 
two  such  surfaces  are  brought  together. 

New  GoldE   Reflex   Slide   Projector 

Projectionists  engaged  in  educational  and 
industrial  showings  will  be  interested  in  the 
new  GoldE  Reflex  300-watt,  blower-cooled 
projector,  which  is  the  only  2%  x  2%  slide 
unit  to  be  built  right  into  the  case.  The 
reflex,  which  has  been  proved  ideal  for  color 
work,  incorporates  a  number  of  patented 
exclusive  features,  one  of  which  is  the  noise- 
less, powerful  blower  cooling  system  which 
keeps  the  entire  outfit  cool  to  the  touch  and 


STRONGS 
TROUPE  W/f/i 

Portable  High  Intensity///! 

A.  C.  CARBON  ARC  SPOTLIGHT 


Produces  a  steady,  sharp,  uniformly 
illuminated  snow-white  spot. 

Silvered  glass  reflector  and  two- 
element  variable  focal  length  lens 
system. 

Draws  only  10  amperes  from  any 
110-volt  A.C.  convenience  outlet. 
Adjustable,  self- regulating  trans- 
former, an  integral  part  of  the  base, 
makes  the  use  of  heavy  rotating 
equipment  unnecessary. 


Easily  operated.  Automatic  arc 
control  maintains  constant  arc  gap, 
free  from  hiss  or  flicker.  A  trim 
of  carbons  burns  one  hour  and  20 
minutes  at  21  volts  and  45  amperes. 

Horizontal  masking  control.  Can 
be  angled  at  45  degrees  in  each 
direction.  Color  boomerang  con- 
tains six  slides  and  ultraviolet  filter 
holder. 

Mounted  on  casters.  Easily  dis- 
assembled for  shipping. 


THE 

STRONG 

ELECTRIC  CORP. 

"The  World's  Largest  Manu- 
facturer of  Projection 
Arc  Lamps" 

Please  send  free  literature,  prices  and  name  of  the  nearest 
dealer  in  Strong  Spotlights. 

NAME                                                    

THEATRE                                                              

1     14   CITY    PARK    AVE.    1 
|j       TOLEDO    2,    OHIO 

STREET                                                      

CITY  &  STATE 

INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


23 


at  room  temperature  at  the  slide  aperture. 
Full   details   available   from   GoldE   Mfg. 
Co.  at  1220  West  Madison  St.,  Chicago  7. 

Distributors   for   Per-Fold   Screen 

Two  supply  houses  have  arranged  to  handle 
the  new  Radiant  Per-Fold  theatre  projec- 
tion screen.  Wil-Kin  Theatre  Supply — of 
Atlanta,  Ga.,  and  Charlotte,  N.  C— will 
cover  Georgia,  the  Carolinas,  and  parts  of 
Florida,  Alabama  and  Tennessee.  Falls  City 
Theatre  Equip.  Co.,  Louisville,  Ky.,  will 
serve  Kentucky  and  Southern  Indiana. 

The  Per-Fold  screen  is  a  perforated  vinyl 
fabric  which  is  said  to  be  washable,  flame- 


for 

SMOOTH 
DEPENDABLE 
D.  C.  Power  Supply 


and  fungus-proof,  and  stain-resistant.  When 
shipped  it  is  not  rolled  but  is  folded  into  a 
compact  package.  Further  details  from 
Jack  Tisch,  Radiant  Mfg.  Corp.,  2627  W. 
Roosevelt  Road,  Chicago  8. 


J.  H.  Kurlander,  Lighting  Expert 

John  H.  Kurlander,  head  of  the  projection, 
photography,  and  miniature  lamp  section  of 
the  Westinghouse  Lamp  Division,  Bloom- 
field,  N.  J.,  died  of  a  heart  attack  in  his 
Nutley,  N.  J.,  home  on  June  24.  Mr.  Kur- 
lander was  best  known  to  projectionists  as 
chief  engineer  of  Brenkert  Light  Projection 
Co.  in  the  1920's  and  as  secretary  of  the 
SMPE  during  1930-37. 

While  at  Westinghouse,  which  he  joined 
in  1929,  Mr.  Kurlander  made  many  impor- 
tant contributions  to  the  lighting  field:  a 
gunsight  lamp  which  eliminated  the  "blind 
spot"  encountered  in  firing  at  enemy  planes 
diving  out  of  the  sun;  a  device  that  produces 
either  a  spot  of  light  or  a  flood  of  light 
from  an  ordinary  hand  flashlight;  a  blue 
bulb  photoflash  lamp  emitting  invisible,  un- 
obtrusive light;  "black  light"  illumination 
for  airplane  instrument  dials;  and  colored 
filter  glass  for  automotive  turn  signals,  pre- 
venting1 "ghost"  signals  caused  by  reflections 
of  sunlight. 

Kurlander  was  credited  by  the  projection 
craft  with  the  ability  to  make  the  Brenkert 
effect  machine  "talk"  because  of  the  ease 
with  which  he  obtained  a  multiplicity  of 
involved  lighting  effects  in  rapid-fire  order. 


MONTHLY  CHAT 

Cooling  Projection  Equipment 

(Continued  from  page  3) 
house  parts,  particularly  for  the  carbon 
jaws,  and  that  it  bears  absolutely  no 
relation  to  either  the  preservation  of  the 
film  nor  to  the  character  of  the  pro- 
jected image — a  fact  which  is  recognized 
and  freely  admitted  by  the  majority  of 
lamp  manufacturers. 

An  increase  in  projected  screen  light 
as  a  result  of  carbon  jaw  water-cooling 
has  never  been  proved  in  any  laboratory 
or  anywhere  else.  Quite  the  contrary  is 
true,  as  is  indicated  by  the  following 
excerpt  from  the  article  by  Messrs.  M.  T. 


Stan,  foenfrvwtcutce  with  STAR  CORE 


Jionft^^ crtdo** 


STAR  CORE,  exclusive  feature  with  the 
Lorraine  Carbons  —  a  manufacturing 
process  that  increases  the  performance 
of  the  carbons. 

A  more  brilliant,  steadier,  more  con- 
sistent white  Jight — more  economically 
. . .  proven  facts  as  shown  by  tests 
made  under  actually  operating  con- 
ditions. 


V/SITt    fO«    DISTRIBUTION    DATA 

CARBONS,  INC. 

BOONTON,  N.J. 

NEW  YORK:  234  WEST  44tfc  STREET 


Jones  and  F.   T.  Bowditch,  of  National 
Carbon  Co.,  on  page  12  of  this  issue: 

"The  outstanding  feature  of  the  water- 
cooling,  combined  with  the  shorter  carbon 
protrusion  which  this  makes  possible,  is  the 
ability  to  carry  much  higher  currents  than 
with  air  cooling,  and  to  attain  higher  bright- 
ness as  a  result.  Within  the  limits  of  satis- 
factory air-cooled  operation,  howevc*,  the 
carbon  reaches  a  higher  brightness  at  a 
given  current  than  when  water-cooled,  so 
that  the  current  efficiency  of  the  carbon  is 
reduced  by  water-cooling." 

Statements  out  of  context  are  often  mis- 
leading; but  from  the  same  article  is 
another  excerpt  which,  in  addition  to  a 
similar  flat  statement  in  the  foreword, 
conveys  the  authors'  opinion  anent  water- 
cooling,  as  follows: 

"The  ability  to  carry  higher  currents  with 
water-cooling  is  not  characteristic  of  all  car- 
bons, however.  [Witness]  the  performance 
of  the  13.6-mm  super  high-intensity  projector 
carbon,  representative  of  the  usual  type  of 
carbon  (see  Fig.  5  in  article).  Here  water- 
cooling  in  no  case  produces  a  higher  bright- 
ness than  can  be  obtained  with  air-cooling, 
and  the  current  efficiency  is  always  less" 
[italics  ours. — Ed.].  "Thus  with  this,  as 
with  most  conventional  types  of  carbons, 
water-cooling  has  no  such  advantage  in  in- 
creasing brightness  as  is  exhibited  by  the 
'high-brightness'  carbon  of  Fig.  4." 

The  effect  of  cooling  the  carbon  jaw  is 
to  pull  some  heat  (energy)  out  of  the 
positive  crater,  thus  permitting  increased 


WITH   ANY 


LAMP 


IN  ANY  SIZE      THEATRE 


RUSSELL  P.  ALLEN— Owner  and 
Manager,  Allen  Theatre  in  Farm- 
ington  and  Allen  Theatre  in  Aztec, 
New  Mexico — says: 
"Since  1930  we  have  used  RCA 
Service  and  found  it  very  efficient 
during  hard  or  good  times.  It  has 
seen   us  through  two  fires.   We 
would  not  be  without  it." 
To  get  the  benefits  of  RCA  Service — 
write:    RCA  SERVICE   COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


PROJECTIONISTS' 
$000  SERVICE 


MANUAL 


24 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


current  and  therefore  greater  agitation 
of  the  electron  particles  in  the  crater. 
Granting  that  the  design  of  the  jaw-cool- 
ing unit  is  satisfactory  (and  not  all  of 
them  are) ,  the  use  of  this  equipment  is 
a  boon  to  the  harassed  lamp  manufac- 
turer who  is  constantly  devilled  by  the 
increasingly  severe  requisites  of  high- 
intensity  arcs  and  the  probable  resultant 
damage  to  lamp  elements. 

But  doesn't  increased  current  density 
and.  .greater  electron  agitation  in  the 
positive  crater  result  in  increased  light 
output  and  therefore  a  brighter  screen 
image?  Could  be — depending  upon  two 
factors  which  are  hardly  ever  mentioned. 

As  stated  in  the  foregoing  quotes  from 
the  Jones-Bowditch  article,  water-cooling 
the  jaws  is  not  effective  in  terms  of  effi- 
cient light  output  with  conventional 
types  of  carbons.  This  method  would  be 
efficient  only  with  carbons  specifically 
designed  for  water-cooling.  Such  carbons 
are  not  now  available  generally,  being  in 
the  experimental  state. 

Another  factor  in  this  situation  which 
is  almost  never  mentioned  is  the  optical 
set-up  employed  in  a  given  lamp.  There 
is  absolutely  no  point  in  pouring  on  the 


» 

7 

ARC    CURRENT    IN    AMPERES 

Showing     how    water-cooling    of    the    positive 

carbon    causes    a    considerable    reduction    of 

crater  brightness  at  the  same  arc  length  and 

current. 

amperage  and  producing  additional  light 
for  transmission  through  an  optical  sys- 
tem that  was  never  intended  to  function 
under  such  conditions. 

Water-cooling  the  carbon  jaw  will  be 
advantageous  in  terms  of  improved  screen 
image  when  the  arc,  using  carbons  de- 
signed specifically  for  the  purpose,  and 
the  optical  system  are  in  precise  balance. 
Meanwhile,  this  method  serves  only  to 
protect  the  lamp   elements. 

Air-Cooled  Aperture.  The  use  of 
blowers  to  cool  the  aperture,  and  the 
film,  is  by  no  means  new,  having  been 
employed  irregularly  for  many  years. 
This  method  received  its  greatest  im- 
petus about  20  years  ago  when  the 
Grandeur  and  the  Spoor  wide-film  sys- 
tems enjoyed  a  brief  vogue.  Of  course, 
these  blowers  served  another  purpose 
than  cooling  with  these  equipments,  aid- 
ing in  maintaining  the  film  on  a  flat 
focal  plane. 

There  can  be  no  question  of  the  effi- 


ciency of  these  blower  units  in  reducing 
the  heat  on  the  film  (again  granting  a 
satisfactory  design  of  the  unit) ,  as  was 
amply  demonstrated  by  F.  J.  Kolb,  of 
Eastman  Kodak  Co.,  in  the  paper1  he 
presented  recently  before  the  SMPE. 

The  Kolb  paper  describes  a  unit  hav- 
ing a  double  nozzle  through  which  air 
is  directed  at  both  sides  of  the  film:  the 
air  directed  to  the  emulsion  side,  where 
the  silver  is  deposited,  accomplishes  the 
actual  cooling  job,  while  the  airflow  to 
the  opposite  side  is  intended  to  aid  in 
keeping  the  film  in  a  flat  plane.    Obvi- 

1  "Air-Cooling  Motion  Picture  Film  for  Higher  Screen 
Illumination";  presented  at  the  Spring,  1949  conven- 
tion of  the  SMPE.  See  abstract  in  IP  for  April, 
1949,    p.    17. 


ously,  the  design  of  the  air  nozzles  and 
the  strength  of  the  air  current  are  vital 
considerations  in  this  system. 

The  conclusion  reached  in  the  Kolb 
paper  (and  nobody  gainsaid  the  state- 
ment) was  that  this  method  enabled  a 
"substantial  increase  in  screen  illumina- 
tion .  .  .  such  increase  being  from  30 
to  60%  beyond  the  present  safe  maxi- 
mum." Here  is  a  cooling  method  which, 
designed  to  protect  only  the  film,  has 
received  widespread  acceptance  among 
technicians. 

Water-Cooled  Aperture.  This  tech- 
nique has  been  employed  intermittently 
for  many  years,  particularly  in  Europe 
where  arcs  pulling  even  a  comparatively 


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moderate  75-85  amperes  have  consistently 
employed  such  units.  There  can  be  no 
question  as  to  the  efficacy  of  this  system 
in  terms  of  doing  the  job  for  which  it  is 
intended — that  is,  the  preservation  of  the 
film,  without  any  relation  to  the  lamp 
mechanism. 

The  foregoing  will  convey  an  idea  of 
the  complexities  of  the  problem  posed 
by  the  intense  heat  of  the  arc.  The 
manufacturers  of  film,  arc  lamps,  pro- 
jectors and,  yes,  even  optics  are  deeply 
concerned  about  this  problem,  which 
challenges  the  ingenuity  of  all  of  them. 

This  leaves  the  carbon  people  right 
in  the  well-known  middle,  because  in 
their  highly  successful  efforts  to  satisfy 
the  insatiable  demand  for  more  and  ever 
more  light  they  have  created  a  Franken- 
steinian  situation  which  promises  to  devil 
them  interminably.  Meanwhile  they  are 
hardly  in  a  position  to  dictate  procedure 
to  the  manufacturers  of  the  other  ele- 
ments of  projection  equipment. 

Single  Unit  Ineffectual 

IP  has  not  attempted  in  the  foregoing 
summary  to  fry  any  prize  fish,  since  it 
realizes  that  any  specific  recommenda- 
tion must  be  predicated  upon  circum- 
stances prevailing  in  a  given  installa- 
tion. However,  it  must  be  apparent  even 
to  he  who  reads  as  he  runs  that  this 
many-sided  problem  is  not  to  be  solved 
by  attributing  to  a  given  unit  or  system 
cure-all  attributes  which  won't  stand  up 
even  on  the  basis  of  superficial  con- 
sideration. 

It  is  incredible  to  IP  that,  considering 
the  gravity  of  this  situation,  there  should 
be  such  a  woeful  lack  of  cooperation  and 
coordination  among  those  whose  function 


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Comparison     of    crater    brightness    of    cooled 
and  uncooled  arcs  at  equal  currents. 

it  is  to  attack  and  solve  such  problems. 
Understandably,  for  example,  the  pro- 
jector manufacturers'  approach  to  the 
problem  would  focus  first  on  the  pro- 
jector, and  the  manufacturers  of  film 
and  arc  lamps  likewise.  But  just  as 
surely  as  a  single  unit  fails  to  meet  the 
requisites  of  this  situation,  just  so  surely 
will  the  effort  of  an  individual  manu- 
facturer fail  to  satisfy  the  broad  require- 
ments of  the  problem  overall. 

IP  makes  bold  to  suggest  that  it 
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SHIRLEY  BOOTH  — Partner, 
Booth  Theatre,  Rich  Hill,  Missouri 
— says: 

"The  Booth  Theatre,  in  con- 
tinuous operation  for  41  years, 
has  used  RCA  Service  since 
1940.  Our  sound  is  kept  at 
peak  efficiency." 
To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
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26 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


for  consideration  of  just  what  need  be 
done,  and  how  best  to  do  it,  to  be  fol- 
lowed by  the  issuance  of  specific  recom- 
mendations applicable  to  a  variety  of 
projection  set-ups.  That  agency  is  the 
SMPE,  which  surely  qualifies  for  the  job 
as  a  party  interested  only  in  coming  up 
with  the  right  answer.  This  neat  little 
job  of  coordinating  the  thoughts  and  ac- 
tions among  a  group  striving  for  the 
answer  to  a  problem  of  such  gravity  to 
the  exhibition  field  would  go  far  to  dis- 
pel the  notion,  widely  circulated  of  late, 
that  the  SMPE  has  been  a  bit  disinter- 
ested in  the  practical  aspects  of  film 
reproduction. 

But  whatever  is  done,  speed  is  of  the 
essence.  It  would  be  a  pity  if  this  situa- 
tion were  to  endure  to  the  point  where 
the  remark  recently  by  an  eminent  light- 
ing technician  would  reflect  the  truth. 
He  said: 

"This  situation  is  one  wherein  gadget 
manufacturers  and  other  irresponsible 
parties  are  trying  to  capitalize  on  the 
imagination  of  projectionists  and  ex- 
hibitors who  are  frantically  seeking  more 
screen  light  and  are  prepared,  figura- 
tively speaking,  to  grasp  at  a  straw  to 
obtain  it." 

BRITISH   vs.  AMERICAN 
PROJECTOR  DESIGN 

(Continued  from  page  10) 
a  century.  Why  the  projectionist  using 
such  equipment  should  be  either  a  super- 
serviceman  or  a  brainless  coot  is  quite 
beyond  my  comprehension.  I  should 
have  thought  any  projectionist  would 
have  been  capable  of  putting  over  a  bet- 
ter show  with  such  machines. 

The  views  on  the  SUPA  are  perhaps  a 
matter  of  opinion;  but  the  statements 
concerning  the  G-K  21  are  without 
question  factually  wrong.  The  buyer  is 
not  tied  to  one  supplier,  because  a  fea- 
ture of  the  design,  I  am  advised,  is  that 
every  individual  component  —  stand, 
mute  head,  soundhead,  arc,  etc.,  is  made 
to  interchange  with  equipment  of  other 
makes. 

Adaptable  to  Every  Circumstance 

To  be  precise,  the  stand  is  designed  to 
take  any  regular  type  of  soundhead.  The 
arc  lamps  are  designed  to  internationally- 
accepted  optical  centres,  and  the  lamp 
supports  will  accommodate  any  type  of 
arc  lamp.  The  optical  centre  of  the  pro- 
jector head  is  to  international  standards 
and,  therefore,  interchangeable,  while 
the  drive  to  the  projector  is  easily  adapt- 
able to  the  drive  originated  by  Simplex. 

Thus,  G-K  sound  equipment  can  be 
used  with  any  type  of  projector  and  any 
type  of  arc  lamp.  Alternatively,  G-K 
projectors  and  arc  lamps  can  be  fitted 
to  any  type  of  sound  system  .  .  . 

Dozens  of  equipments  throughout  the 


country  are  using  Magnarc  and  Ross 
arcs  with  G-K  projectors  on  Western 
Electric  Universal  base.  In  other  cases, 
G-K  soundheads  are  used  with  Simplex 
projectors  and  Ross  arcs.  Similarly, 
G-K  sound  equipment  is  used  with  Erne- 
mann  projectors. 

IP's  Editor  Has  His  Say 

Before  one  may  comment  intelligently 
upon  the  foregoing,  it  seems  in  order  to 
have  a  definition  of  terms.  Mr.  Cricks' 
use  of  the  phrase  "years  ahead  of  Ameri- 
can design"  would  seem  to  imply  that 
such  advances  (?)  in  design  in  them- 
selves inevitably  produce  a  screen  image 


better  than  that  possible  with  American 
projectors. 

Mr.  Cricks  took  the  first  aggressive 
step  by  making  the  positive  statement 
that  the  new  British  designs  enabled  a 
superior  screen  image;  IP  merely  re- 
marked, in  passing,  that  this  was  cover- 


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INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


27 


ing  quite  a  chunk  of  territory.  One 
would  naturally  assume  that  a  new  de- 
sign would  produce  an  improved  screen 
image;    but  such  an  assumption,  in  the 


eloquently   precise   lyrics  of  Porgy   and 
Bess,  ain't  necessarily  so. 

The  function  of  a  projection  apparatus 
is  to  give  the  best  possible  screen  image 


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— which,  freely  translated,  means  the 
most  light  over  the  greatest  area  with  the 
best  definition  and  the  maximum  degree 
of  image  steadiness.  The  mere  fact  tne 
latest  British  projector  designs  are 
pleasing  to  the  eye  does  not  mean  that 
they  discharge  the  aforementioned  func- 
tions with  any  more  efficiency  than  do 
the  American  projectors  now  available. 
True,  British  mechanisms  are  "inter- 
changeable" with  various  other  units,  but 
this  in  itself  adds  not  one  lumen  nor 
more  definition  nor  more  steadiness  to 
the  screen  image:  this  has  long  been  the 
goal  of  projector  manufacturers  the 
world  over — British,  Dutch,  German,  or 
American. 

Curved  Gates,  Independent  Drives 

Curved  gates  are  "old  hat"  in  Ameri- 
can projector  design:  we  did  this  when 
we  essayed  the  ill-fated  65-mm  wide- 
film  experiment  in  the  '30's;  independent 
drives  are  also  nothing  new  to  American 
technique,  as  was  so  magnificently  dem- 
onstrated by  the  RCA-Walt  Disney  ap- 
paratus for  the  roadshowing  of  Fantasia, 
which  setup  employed  Selsyn  interlocks 
which  would  put  to  shame  the  so-called 
"independent"  drives  for  picture  and 
sound  which  now  are  clarioned  by  Brit- 
ish manufacturers  as  the  last  word  in 
projection  technique. 

The  true,  the  only  significant  test  of 
any  projection  mechanism  is  the  quality 
of  the  screen  image.  On  this  score  we 
are  willing  to  wager  that  any  of  four 
existing  American  mechanisms  will  at 
least  match,  if  not  actually  exceed,  in 
quality  of  screen  image  the  production 
of  these  "new"  British  designs.  In  this 
statement  we  are  not  motivated  by  any 
"patriotic  impulse":  we're  willing  to  let 
the  screen  image  reflect  its  own  quality. 

Too  Easy  Transition  Effected 

We  regard  Mr.  Cricks  as  one  of  the 
best  informed  and  most  able  commenta- 
tors on  cinematography  in  the  world  (in- 
cluding the  U.S.A.)  and  we  have  en- 
joyed his  writings  for  many  years.  But 
we  are  forced  of  necessity  to  take  a  differ- 
ent lane  when,  quite  apart  from  his  off- 
the-cuff  allusion  to  our  "patriotic"  mo- 
tives in  assaying  projectors,  he  blithely 
endows  a  "new"  design  with  end  results 
superior  to  those  American  projectors 
which  have  for  years  performed  in  such 
fashion  as  to  set  the  standard  for  the 
world. 

Moreover,  we  have  again  checked  with 
our  Canadian  friends  who  have  been  op- 
erating the  G-K  21  projector,  and  their 
advice  conforms  to  their  original  reports 
on  this  mechanism:  far  from  having 
licked  the  "teething"  trouble  indigenous 
to  most  new  equipments,  the  G-K  21's 
still  require  that  degree  of  close  atten- 
tion and  periodic  servicing  that  was  un- 
known when  American  projectors  were 
used. 


28 


INTERNATIONAL  PROJECTIONIST 


JULY  1949 


DISTORTION   FACTORS   IN 
SOUND  REPRODUCTION 

(Continued  from  page  6) 
soundheads  (accompanied  by  reduction 
of  volume  and,  with  variable-area  tracks, 
non-linear  distortion)  ;  warping  circuit 
or  tone  control  not  properly  adjusted; 
failure  of  high-frequency  speakers,  and 
impedance  of  one  of  the  many  amplifier 
circuits  incorrect  (due  perhaps  to  a 
short-circuit  or  to  leaving  the  non-sync 
pickup  connected  to  the  input  circuit) . 

3.  Loss  of  Lows.  (This  is  also  a 
special  case  of  frequency  distortion.) 
Symptoms:  Music  thin  and  tinny;  ordi- 
nary noises  crackly  and  hissy;  voices 
clear,  but  all  sound  nearly  alike  and 
rather  shrill. 

Causes:  Failure  of  low-frequency 
speakers,  warping  circuit  or  tone  control 
not  properly  adjusted,  and  open-circuited 
or  leaky  condenser  in  a  low-pass  circuit. 

4.  Non-Linear     Distortion.     Symp- 


The  motion  picture  projector  and  all  of  its 
components  are  fully  described  in 

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or  film  breaks,  motor  slops. 

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Send  for  Bulletin  No.  456 


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toms:  Sound  which  is  unnaturally  harsh, 
shrill,  raspy,  or  blurred.  A  non-linear 
distortion  factor  under  5%  cannot  be 
detected  by  the  human  ear. 

Causes:  As  this  type  of  distortion  may 
be  present  in  the  film  or  disc  records,  a 
hasty  diagnosis  should  not  be  made. 
When  the  non-synchronous  gramophone 
produces  a  non-linear  output,  look  for  a 
worn  needle  or  a  worn  or  defective 
record. 

Common  Distortion  Factors 

We  instinctively  check  the  tubes  of  the 
amplifier  when  non-linear  distortion  ap- 
pears, for  defective  tubes  are  the  most 
common  cause.  Other  causes  include  a 
too  low  ionizing  potential  for  the  photo- 
electric cells,  too  low  filament  currents 
or  plate  voltages  for  the  amplifier  tubes, 
insufficient  magnetizing  current  for  the 
speaker  fields,  and  out-of-focus  sound- 
head optics.  (The  latter  also  cuts  off 
high  frequencies.)  The  trouble-shooter 
will  therefore  check  the  various  voltages 
and  currents  mentioned  to  get  at  the 
root  of  the  trouble. 

Remarks:  An  accurate  determination 
of  non-linear  distortion  produced  in  the 
sound  system  can  be  made  only  by  ob- 
serving the  distortion  produced  in  the 
sine-wave  curve  on  the  cathode-ray  tube 
of  an  oscilloscope  when  test  films  or  discs 
of  pure  tones  are  played. 

Speaker  rattles  may  also  be  classed 
under  non-linear  distortion,  even  though 
the  cause  is  purely  mechanical  and  more 
or  less  frequency-selective.  Rattles  and 
raspy  noises  are  most  likely  to  occur 
during  loud  sounds  and,  if  frequency 
distortion  is  present,  only  at  certain  fre- 
quencies of  sound  as  a  rule.  Speakers 
(including  the  monitors  in  the  projection 
room)  should  be  checked  for  rattles 
every  few  months.  Naturally,  the  con- 
dition of  the  cones  or  diaphrams  will  be 
noted  during  such  checkups. 

5.  Travel  Distortion.  An  uneven 
motion  of  the  film  through  the  sound- 
head scanning  beam  (or  of  the  gramo- 
phone record  under  the  pickup  needle) 
results  in  several  peculiar  types  of  dis- 


Seamless,  Tearproof  Plastic  Screen 

A  seamless,  tearproof  plastic  screen  which 
is  said  to  defy  rupture  and  automatically 
recover  from,  dents  and  depressions,  remain- 
ing flexible  indefinitely,  is  announced  by 
Williams  Screen  Co.,  Akron,  Ohio.  It  is  not 
subject  to  contraction  or  expansion  as  a 
result  of  moisture. 

Plastic  construction  permits  even,  clear- 
cut  perforations,  wth  no  projecting  fibers 
to  collect  dust  and  impede  sound  trans- 
mission. The  screen  will  not  support  com- 
bustion as  it  is  resistant  to  most  chemicals. 
Available  in  either  silver  or  white,  the 
screen  is  given  a  protective  coating  which 
is  easily  removed  at  installation  time. 

Free  samples  of  the  material,  literature 
and  prices  are  available  from  Williams  at 
1677  Summit  Lake  Blvd.,  Akron  7. 


CARL  E.  ANDERSON  — Owner 
and  Manager,  Liberty,  Strand  and 
Roxy  Theatres,  Kalispell,  Montana 
— says: 

"RCA  Service  and  equipment 

are  certainly  tops.  Not  once  in 

20  years  have  we  had  cause 

for  even  a  single  complaint." 

To  get  the  benefits  of  RCA  Service — 

write:    RCA   SERVICE    COMPANY, 

INC.,  Radio  Corporation  of  America, 

Camden,  N.  J. 


INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


29 


tortion,  each  of  which  has  been  given  a 
descriptive  appellation. 

Symptoms:  Wows,  flutter,  gargle,  and 
whiskers.  If  the  variations  are  either 
irregular  or  of  any  frequency  up  to  5 
c.p.s.,  the  effect  is  known  as  "wows"; 
il  of  some  frequency  between  5  and  30 
c.p.s.,  it  is  called  flutter;  between  30  and 
200  c.p.s.,  "gargle" ;  and  if  over  200  c.p.s., 
it  is  known  as  "whiskers."  "Gargle"  can- 
not be  heard  in  the  bass  tones,  and 
"whiskers"  are  heard  only  as  a  raspy 
quality  imparted  to  the  high  notes:  for 
this  reason  "whiskers"  may  be  wrongly 
interpreted  by  the  untrained  listener  as 
non-linear  distortion. 

Causes:  Wows  may  be  caused  by 
grime-caked  grease  in  rotary  stabilizer 
bearing  races,  or  by  insufficient  pressure 
— roller  tension  on  the  scanning  drum. 
Wows  and  flutter  are  often  caused  by 
insufficient  gate  tension  in  the  old-style 
soundheads — often  well-nigh  incurable  in 
those  antiquated  models  having  an  "im- 
pedance roller"  interposed  between 
sound  sprocket  and  gate.  "Gargle"  and 
"whiskers"  are  caused  by  insufficient 
gate  tension  and  worn  sound-sprocket 
teeth  in  old-fashioned  soundheads;  also 
by  a  fluttering  piece  of  lint  accidentally 
lodged  in  the  sound  gate. 

Note  that  all  forms  of  travel  distortion 
may  be  produced  by  bent  or  sprung 
sound-sprocket  shafts  in  certain  obsolete 
soundheads ! 

Extraneous  Noise  Sources 

6.  Extraneous  Noises.  These  are 
classified  as  types  of  distortion,  although 
actually  they  are  not.  Extraneous  noises 
result  from  the  superimposition  of  un-, 
wanted  externally-generated  signals  upon 
the  recorded  signal.  When  the  film  is  at 
fault  through  scratches — an  excessively 
large  number  of  splices,  coarse  silver 
grains,  etc. — little  can  be  done  about  it. 
Cutting  off  the  higher  frequencies  of 
sound  by  means  of  a  variable  tone  con- 
trol eliminates  some  of  the  hissing  sur- 
face noise,  but  it  also  spoils  the  "bril- 
liance" of  the  recording. 

Offending  splices  may  be  blooped  over 
with  Movietone  ink;  but  the  bloops,  in 
order  to  be  effective,  must  be  at  least 
one  inch  in  length  and  very  smoothly 
graduated.  Inexpertly-made  bloops  create 
more  noise  than  do  bare  splices. 

Frame-line  noise  and  sprocket-hole 
"motor-boating,"  if  not  due  to  misalign- 
ment in  printing,  indicate  that  adjust- 
ment of  the  soundhead  lateral  film  guide 
is  needed. 

Power-line  hum  (120  d.v.  if  60-cycle 
current,  100  d.v.  if  50-cycle)  may  find 
its  way  into  the  sound  system  because 
of  a  burned-out  rectifier  tube,  a  defective 
power-amplifier  tube,  inductive  pickup 
by  amplifier  circuits  from  an  unshielded 
power-supplying  transformer,  inductive 
or  capacitative  pickup  by  photocell  leads 
or   speaker   cables,   short-circuited   filter 


chokes  or  open-circuited  filter  condens- 
ers, or  light  from  the  projection  room 
falling  upon  the  photocells.  Hum  from 
nearby  high-voltage  neon  signs  is  easily 
picked  up. 

A  strong  clattering  96  d.v.  "hum" 
sometimes  accompanied  by  a  faint  60-  or 
120-cycle  hum  or  a  high-pitched  squeal, 
is  caused  by  light  from  the  projection 
head  leaking  into  the  photocell — usually 
by  reflection  from  some  object  like  the 
glass  in  the  projector  port. 

Recurring  clicks  are  caused  by  film 
splices,  by  film  marred  by  "sprocketing," 
by  marquee  flashers,  and  by  sundry  elec- 
trical devices  in  the  theatre  or  surround- 
ing buildings.  Electrical  shielding  of 
the  disturbing  device  is  indicated. 

The  'Small-Shot'  Effect 

A  curious  type  of  clicking  noise  war- 
rants special  mention  because  it  has 
occasioned  much  needless  worry.  The 
crackles  sometimes  heard  when  a  sound 
system  is  warming  up  are  usually  due, 
not  to  loose  connections  or  something  on 
the  verge  of  burning  out,  but  to  the 
Schroteffekt  (German  for  "small-shot 
effect").  This  phenomenon,  common  to 
nearly  all  types  of  amplifier  and  radio 
tubes,  has  been  explained  on  the  basis 
of  statistical  variations  in  the  number  of 
electrons  per  second  emitted  by  the  tube 
cathode. 

One  need  not  become  alarmed  by  such 
sputtering  and  popping  noises.  They 
cannot  be  helped  and  they  do  no  harm. 

Squeals  and  whistles  in  the  sound  are 
usually  due  to  microphonic  tubes.  Such 
tubes,  while  they  may  be  otherwise  good, 


HENRYS.  BE  ARDSLEY— Owner, 
Chief  Theatre,   Oberlin,   Kansas — 
says: 
"After  nineteen   years   of  RCA 
Service  we  still  consider  it  our 
best  assurance  of  continued  sat- 
isfactory sound  presentation." 
To  get  the  benefits  of  RCA  Service — 
write:   RCA  SERVICE    COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


have  elements  which  were  loosened  in 
manufacture  or  by  rough  handling.  The 
loose  elements  within  the  tube  begin  to 
vibrate  and  the  vibrations,  by  varying 
the  distance  between  the  elements,  cause 
the  plate  current  to  be  affected  propor- 
tionately. The  slight  variations  in  the 
current  are  amplified  to  a  singing  howl. 
But  squeals  and  howls  may  also  be 
caused  by  wornout  tubes  with  low  elec- 
tronic emission.  All  tubes  should  be 
checked  periodically. 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

INTERNATIONAL    PROJECTIONIST. 

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INTERNATIONAL  PROJECTIONIST     •     JULY  1949 


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postage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  1.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


Send  fah  it  Wow! 


(Do  Wot  (Delay 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18.  N.  Y. 

Gentlemen:  Enclosed  find  $3.00  for  a  copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 

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.  for  the  projection  equipment  that  delivers  to  yo«r 
screen  a  more  brilliant  picture,  a  steadier  image 
and  the  most  lifelike  quality. 

.for  sound  systems  that  have  ample  power  to 
bring  crystal  clear  sound  right  to  your  patron's 
car  whether  it  be  in  the  first  or  last  ramp. 

.  for  smartly  styled  In-A-Car  speakers  whose  smooth 
performance  is  always  fops  with  your  patrons. 


LOOK  AHEAD  T0^   1^*  F0R  YOU 
"    *    LOOKS  AHEAD  W* 


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PROJECTION     M 

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&  SOUND       !§ 

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IT  CAN  BE  DONE 
...but  don't  try  it! 


Sometimes  it's  possible  to  break  all  the  rules — 
and  get  away  with  it. 

The  famous  Tower  of  Pisa,  for  instance,  has 
successfully  defied  both  sound  engineering  prac- 
tice and  the  law  of  gravity  for  over  800  years. 

But  for  most  of  us,  most  of  the  time,  the  rules 
hold. 

That  is  particularly  true  when  it  comes  to  sav- 
ing money. 

The  first  rule  of  successful  saving  is  regularity 
.  .  .  salting  away  part  of  every  pay  check,  month 
after  month. 

Once  in  a  blue  moon,  of  course,  you'll  come 
across  someone  who  can  break  that  rule  and  get 
away  with  it.  But  the  fact  is  that  most  of  us 
cannot. 

For  most  of  us,  the  one  and  only  way  to  accum- 
ulate a  decent-size  nest  egg  for  the  future  and  for 
emergencies  is  through  regular,  automatic  saving. 

In  all  history  there's  never  been  an  easier, 
surer,  more  profitable  way  to  save  regularly  than 
the  U.  S.  Savings  Bond  way. 

Those  of  us  on  a  payroll  are  eligible  to  use  the 
wonderful  Payroll  Savings  Plan.  The  rest  of  us 
can  use  the  equally  wonderful  Bond-A-Month 
Plan  through  our  local  bank. 

Use  whichever  is  best  for  you.  But — use  one 
of  them! 


AUTOMATIC  SAVING 
IS  SURE  SAVING- 
U.S.  SAVINGS  BONDS 


Contributed  by  this  magazine  in  co-operation  with  the 
Magazine  Publishers  of  America  as  a  public  service. 


tgfsmr"': 


INTERNATIONAL 

PR0JECTI0NIS1I 


With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


AUGUST  1949 


Number  8 


Index  and  Monthly  Chat 3 

Lens  and  Film  Factors  Affecting 

Focus     5 

Robert  A.  Mitchell 

Recent  Film  Technical  Advances       9 
SMPE  Progress  Committee 
Report 

Accuracy   of   Unsteadiness   Test 
Films     io 

The  Great  Enigma:    The  Stereo- 
scopic Perspective    13 

Theodore  H.  Nakken 

In  the  Spotlight   16 

Harry  Sherman 


Chicago  Theatre-WBKB  Inter- 
mediate Full-Screen  Tv-Film 
System     18 

The  Origins  of  the  'Magic  Lan- 
tern'           19 

J.  Voskuil 

Telecasts .      20 

Pulsed  Light  Optical  Unit  for 
RCA  TP-35B  Projector 21 

Letters  to  the  Editor   22 

New  Century  Soundfilm  Systems 
Reflect  Latest  Advances    ....      22 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING   CO.,   INC. 

19  West  44  Street,  New  York   18,  N.   Y. 

R.   A.    ENTRACHT,   Publisher 

SUBSCRIPTION   REPRESENTATIVES 

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ENGLAND  and  DOMINIONS:  Win.  Dawson  &  Sons,  Ltd.,  Macklin  St.,  London,  W.  C.  2 

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two  weeks  in  advance  of  publication  date  to  insure  receipt  of  current  issue.  Entered  as 
second-class  matter  February  8,  1932,  at  the  Post  Office  at  New  York,  N.  Y.,  under  the 
act  of  March  3,  1879.  Entire  contents  copyrighted  1949  by  International  Projectionist 
Publishing  Co.,  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


.420 


MONTHLY   CHAT 

THERE  are  many  items  of  a  non-tech- 
nical nature,  properly  classified  per- 
haps under  the  heading  of  "good  and 
welfare,"  which  should  be  reported  and 
discussed  in  the  columns  of  a  craft  paper 
such  as  IP  predominantly  is.  For  the 
true  craft  paper  should  concern  itself 
not  only  with  the  technical  savvy  of  its 
readers .  but  also  with  their  economic 
well-being,  i.  e.,  their  security,  which  in 
turn  is  dependent  upon  the  economic 
health  of  the  industry  in  which  they 
work.  Particularly  is  this  true  of  the 
motion  picture  industry,  the  nerve  cen- 
ters of  which  are  almost  continually 
jarred  by  the  mental  gyrations  of  those 
executives  who  guide  its  course. 

Pointing  up  the  growing  appreciation 
of  continuing  industrial  economic  health 
among  workers  in  every  business  is  the 
current  tendency  by  Labor  to  forgo  the 
immediate  benefits  of  wage  increases  in 
favor  of  the  long-term  advantage  of  pay- 
ments for  health,  retirement  and  death — • 
security  with  a  capital  S.  This  tendency 
is  not  pronounced  at  present  in  the  en- 
tertainment field,  but  now  that  the  first 
step  has  been  taken  by  Chicago  Local 
110  in  its  memorable  contract  settlement 
of  1948,  we  may  expect  to  see  many 
travelers  along  this  road. 

We  think  it  important  that  projection- 
ists know,  for  example,  the  economic 
effects  upon  their  industry,  their  jobs 
of  the  decrease  in  income  from  the  sale 
of  American  films  abroad;  of  the  in- 
crease or  decrease  in  the  number  of  pic- 
tures now  rolling  in  Hollywood  studios 
and  scheduled  for  the  balance  of  this 
season;  of  the  government-enforced 
breakup  of  the  theatre  chains  now  con- 
trolled by  producers  and  distributors;  of 
the  trend  of  theatre  admission  prices 
nationally;  of  the  total  box-office  take 
as  related  to  last  year  and  the  year  be- 
fore; of  labor  contract  settlements,  ad- 
vantageous or  otherwise — in  short,  of  all 
those  industry  happenings  which  ulti- 
mately must  filter  down  and  affect  the 
security  of  both  Joe  Doakes  in  a  Broad- 
way theatre  and  of  Joe  Miller  in  a  sub- 
sequent-run in  Walla  Walla. 

Just  because  projection  work  by  its 
very  nature  is  so  very  confining  is  no 
reason  why  its  practitioners  must  operate 
in  an  informational  vacuum,  especially 
where  the  net  result  of  all  their  labor, 
their  security,  is  concerned.  Technical 
data  is  a  "must"  for  projectionists,  of 
course,  and  IP  is  justly  proud  of  the 
fine  record  it  has  compiled  in  dissemi- 
nating such  information.  But  IP  pro- 
poses doing  something  about  disseminat- 
ing in  one  special  corner  of  each  edition 
that  information  which  affects  the  basic 
needs  and  aspirations  of  its  readers — 
their  security. 

The  next  issue  of  IP,  then,  will  mark 
the  inaugural  bow  of  a  section  which  will 
provide  projectionists  with  a  better  un- 
derstanding of  the  industry  to  which  they 
look  for  their  security. 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


■  "l."1- ."" 


USE  THIS  COUPON  TODAY  FOR  DEMONSTRATION  OR  LITERATURE 


THE  STRONG  ELECTRIC  CORPORATION 

/  ,    ;'-((  '   31  City  Park  Avenue  Toledo  2,  Ohio 

!'';•,',  D  '  would   like  a  demonstration  of  Strong  lamps  in  my  theatre,  without  cost  or 

\'i       'V     "■  obligation. 

*M$$$$$l$        D  Please  send  free  literature  on  the: 

)  ,  l         □  Mogul  Lamp  Q]  Utility  Lamp  Q]  Strong  Arc  Spotlamps 

□  Strong  Rectifiers  □  Strong  Reflectors 


[     ^k^i^^  STRONG  tie /otditteatufte/     )  city  and  state 


NAME  — 
THEATRE- 
STREET- 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


INTERNATIONAL    PROJECTIONIST 


VOLUME  XXIV 


AUGUST  1949 


NUMBER  8 


Lens  and  Film  Factors  Affecting  Focus 


COMMERCIAL  television  has  done 
more  than  anything  else  to  direct 
attention  to  definition  in  picture 
images,  both  televised  and  projected. 
Video  image  quality  is  constantly  com- 
pared with  that  of  the  movies,  and  it  is 
obvious  to  all  that  Tv  falls  far  short  of 
the  35-mm  motion  picture  in  clearness, 
pictorial  scope,  and  ease  of  viewing — a 
fact  even  more  irritating  than  the  lack 
of  natural  color  to  those  who  had  ex- 
pected to  find  in  Tv  an  acceptable  sub- 
stitute for  the  dramatically  mighty  screen 
of  the  motion  picture  theatre. 

The  theatre  projectionist  has  a  large 
share  of  the  responsibility  of  maintain- 
ing the  supremacy  of  the  standard  mo- 
tion picture  over  its  competitors  in  the 
substandard  (16-mm)  and  Tv  fields. 
The  maximum  degree  of  clearness,  bril- 
liance, and  vivid  contrast  in  the  screen 
image  is  the  hallmark  of  first-class  pro- 
jection. 

Factors  Affecting  Definition 

Ultimately,  the  definition  of  a  pro- 
jected motion  picture  is  limited  physi- 
cally only  by  the  size  of  the  silver  grains 
in  the  developed  film  emulsion  and  by 
the  resolving  power  of  the  projection 
lens.  The  film  and  the  lens,  therefore, 
receive  the  lion's  share  of  attention  when 
improvements  in  image  definition  are 
demanded. 

It  should  not  be  supposed,  however, 
that  these  are  the  only  factors  affecting 
the  clearness  and  contrast  of  the  picture. 
The  performance  of  the  projection  arc 
lamp  is  an  extremely  important  factor. 
So,  too,  are  the  screen  surface,  the  glass 


By  ROBERT  A.  MITCHELL 

in  the  projector  ports,  the  projector 
mechanism,  and  even  the  general  audi- 
torium illumination  conditions. 

The  projection  lens  has  been  charac- 
terized as  the  neck  of  the  bottle  through 
which  the  concerted  efforts  of  the  in- 
dustry must  pass.  If  the  lens  is  injured, 
soiled,  or  otherwise  defective,  it  will  im- 
pair image  definition  by  (a)  failing  to 
bring  the  image  to  a  sharp  focus  in  one 
or  more  areas  of  the  screen,  (b)  focus- 
ing sharply,  but  producing  a  luminous 
mist  over  all  bright  objects  in  the  pic- 
ture, or  (c)  reducing  overall  contrast  in 
such  a  way  that  the  darker  tones  of  the 
picture  "wash  out"  to  give  dirty  and 
chalky  grays. 

Any  lens  which  is  unable  to  form  a 
sharp,  clear-cut  image  over  the  entire 
screen  surface  is  absolutely  unfit  for 
use.  The  original  price  of  a  lens  and 
the  prestige  of  its  maker  are  as  nothing 
in  the  face  of  actual  performance.  Many 
of  the  older  lenses  (including  a  few  ex- 
pensive, imported  ones)  produce  a 
blurred  image  of  the  edges  of  the  pic- 
ture when  the  center  is  sharply  focused. 
Any  attempt  to  sharpen  the  edges  will 
blur  the  middle. 

Modern  lenses  of  good  quality  are  de- 
signed to  provide  a  uniform  and  flat 
field,  and  are  remarkably  free  from 
spherical  and  astigmatic  defects. 

Blurred  picture  edges  are  often  pro- 
duced by  the  camera  lens  and  photo- 
graphed on  the  film,  a  circumstance  in 
which  the  projectionist  is  helpless.    But 


an  out-of-focus  edge  or  corner  of  the  pic- 
ture is  also  caused  by  a  worn  condition  of 
the  projector  film  gate,  about  which  the 
projectionist  can  do  plenty. 

Effect  of  Lens  Injuries 

Scratches  on  any  of  the  delicate  and 
highly  polished  glass  surfaces  of  the 
lens  "elements"  impair  image  definition 
by  scattering  bght  from  the  brighter  to 
the  darker  portions  of  the  picture.  The 
result  is  a  lowered  contrast  somewhat 
like  that  caused  by  extraneous  light 
"fogging"  the  screen. 

One  or  two  deep  scratches  on  a  lens 
look  very  alarming  indeed,  but  they  are 
not  as  detrimental  to  picture  quality  as 
a  multitude  of  very  fine  scratches  all 
over  a  lens  surface.  Now,  small  scratches 
are  the  inevitable  result  of  injudicious 
cleaning  methods  —  vigorous  scrubbing 
and  scouring,  and  the  use  of  lens  pow- 
ders, pastes,  carbon  tetrachloride,  al- 
cohol, and  soiled  cleaning  cloths. 

At  first  the  scratches  are  so  small  as 
to  be  actually  invisible  to  the  unaided 
eye,  but  they  are  there,  and  their  num- 
ber increases  every  time  the  lens  is  sub- 
jected to  abusive  cleaning.  In  the  course 
of  a  few  years  the  "invisible"  scratches 
are  so  numerous  that  the  lens  appears 
etched  or  frosted;  and  the  picture,  in- 
stead of  having  "snap,"  is  dulled  by  a 
veil  of  dispersion  fog. 

All  that  is  needed  in  the  way  of  lens- 
cleaning  materials  are  a  small  camels- 
hair  brush,  a  quantity  of  2-inch  squares 
of  clean,  dust-free  cotton  cloth,  a  clean- 
ing solution  made  by  dissolving  a  piece 
of  Ivory  soap  the  size  of  a  large  pea  in 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


a  pint  of  pure  (distilled)  water,  and  a 
bottle  of  distilled  water  for  rinsing  off 
any  scum  which  may  remain  after  gentle 
cleansing  with  the  soap  solution. 

The  soap  solution  is  to  be  used  spar- 
ingly for  removing  oil,  finger-marks,  etc., 
from  the  lens  and  only  for  this  purpose. 
It  is  not  to  be  used  for  the  more  or  less 
routine  removal  of  dust  from  the  lens. 
(Dust  is  gently  brushed  off  with  a 
camels-hair  brush  or,  if  particularly 
stubborn,  with  a  square  of  dry  cotton 
cloth.) 

Laundry  soaps  and  soap  powders 
should  never  be  used  for  making  up  the 
cleaning  solution  because  they  may  con- 
tain trisodium  orthophosphate,  borax, 
or  an  excess  of  caustic  soda — substances 
possessing  the  dangerous  potentiality  of 
chemical  reaction  with  glass.  The  soap- 
less  detergents  (hymolal  salts)  are  them- 
selves harmless  to  lenses,  but  most  of  the 
soap  powders  containing  them  are  liber- 
ally adulterated  with  harsher  agents,1 

The  individual  elements  of  achromatic 
projection  lenses  are  themselves  com- 
posite. In  most  cases  the  components 
of  a  lens  element  are  cemented  together 
with  a  transparent  plastic  material  in 
order  to  reduce  surface  reflections  which 
diminish  contrast  and  dull  the  image. 

Balsam  as  a  Cementing  Medium 

The  cementing  material  employed  in 
practically  all  of  the  older  lenses  was 
Canada  balsam,  the  refined  resinous  exu- 
dation of  the  fir  tree.  Canada  balsam 
deteriorates  with  age,  and  the  heat  of 
the  arc-lamp  beam  hastens  decomposi- 
tion and  often  causes  it  to  blister.  When 
the  balsam  is  discolored  and  frilled, 
image  definition  suffers.  The  effect  on 
the  picture  is  even  worse  than  that  pro- 
duced by  a  soiled  lens. 

The  use  of  alcohol  as  a  lens-cleaning 
fluid  also  causes  the  balsam  to  frill  and 
separate  from  the  glass,  the  blistering 
beginning  at  the  edges  of  the  lens  and 
gradually  working  in  toward  the  center. 
This  bad  practice  is  perpetuated  by  an 
equally  bad  projection  textbook  which 
disastrously  recommends  "a  mixture  of 
half  clean  water  and  half  grain  alcohol" 
for  cleaning  lenses.  This,  be  assured,  is 
a  lethal  cocktail  for  any  lens.  Carbon 
tetrachloride,  chloroform,  acetone,  and 
ether  may  also  cause  irreparable  damage. 

Lenses  disabled  by  blistered  and  dis- 
colored balsam  should  be  returned  to  the 
manufacturer  for  servicing.  The  cement- 
ing of  lenses  should  not  be  attempted  in 
the  projection  room. 

Modern  American  lenses  of  the  best 
quality  utilize  special  heat-resistant  ther- 
mosetting resins,  synthetic  products 
which  are  vastly  more  durable  than 
Canada  balsam.    But  this  does  not  mean 


1  Sec  'Coaled  Lenses:  Nature  and  Care"  by  A.  E. 
Murray  (IP  for  February,  1949,  p.  7)  for  a  complcta 
exposition   of  approved   lens-cleaning  metbods. 


that  they  are  unaffected  by  organic  sol- 
vents ! 

The  distance  between  the  film  and  the 
lens  which  gives  the  sharpest  focus  on 
the  screen  is  extremely  critical.  The 
slightest  deviation  from  this  definite 
"focal  distance"  reveals  itself  as  a 
blurred  picture,  a  condition  to  be  recti- 
fied by  adjusting  the  separation  of  lens 
and  film  to  re-establish  the  correct  focal 
distance.  Theoretically,  this  adjustment 
could  be  made  by  moving  either  the  lens 
or  the  film  along  the  optical  axis  of  the 
projector,  but  in  practice  focusing  is 
accomplished  by  changing  the  position 
of  the  lens  only,  the  film-plane  obviously 
being  fixed. 

Focus  Variations  Unavoidable 

So  self-evident  is  this  elementary  prin- 
ciple that  many  projectionists  have  been 
inclined  to  overlook  the  tremendously 
important  fact  that  even  though  the  dis- 
tance of  the  tiny  film-photograph  from 
the  fixed  aperture  is  not  manually  ad- 
justable, it  is  subject  to  short-range 
variations  which  produce  corresponding 
variations  in  the  focus. 

Although  we  know  that  the  film-photo- 
graph will  lie  somewhere  within  a  close 
region  facing  the  aperture  plate,  we  can 
never  tell  exactly  where  it  will  be.  And 
yet  the  correct  focal  distance  must  be 
maintained  at  all  times  in  order  to  avoid 
out-of -focus  screen  images! 

Considering  the  fact  that  film  has  an 
appreciable  thickness  (about  0.00575  of 
an  inch)  and  that  only  a  thin  layer  on 
one  side  of  the  film  (the  photographic 
image  in  the  emulsion)  is  to  be  focused 
sharply,  the  other  layers  being  neces- 
sarily slightly  out  of  focus,  we  can'  esti- 
mate that  the  film-photograph  at  the 
aperture  has  an  average  range  of  pos- 
sible in-and-out  variation  of  position  of 
approximately  0.005  of  an  inch.  In  ex- 
treme cases  (warped  and  buckled  film) 
this  range  may  be  exceeded. 

The  position  which  the  film-photograph 
chooses  to  occupy  inside  this  0.005-inch 
region  directly  in  front  of  the  aperture 
depends  solely  on  the  type  and  condi- 
tion of  the  film.  It  is  beyond  the  control 
of  the  projectionist. 

Now,  the  position  of  the  film-photo- 
graph may  remain  sensibly  constant 
throughout  the  entire  length  of  a  print, 
requiring    but    a    single    setting    of    the 


lens,  or  it  may  undergo  either  random 
or  progressive  variations  in  the  same  reel, 
requiring  constant  attention  to  the  main- 
tenance of  focus. 

Spontaneous  variations  in  film-photo- 
graph position  result  in  image  flutter 
and  focus  drift.  Differences  in  average 
position  are  noted  between  different 
prints,  and  especially  between  black- 
and-white  and  color  prints.  In  most  cases 
the  difference  does  not  exceed  0.001  or 
0.002  of  an  inch,  but  even  this  small  de- 
parture from  critical  focal  distance  pro- 
duces a  noticeable  loss  of  image  defini- 
tion. 

The  maximum  deviation  of  about  0.005 
of  an  inch  occurs  with  frame-embossed, 
curled,  and  buckled  film,  and  also  with 
"reversed"  films  which  have  to  be  pro- 
jected with  the  emulsion  facing  screen- 
ward  instead  of  toward  the  lamp,  as  in 
the  case  of  normal  films  printed  from 
negatives. 

Is  it  not  obvious  that  projection  qual- 
ity will  be  poor  if  the  projectionist  fails 
to  make  occasional  focus  adjustments 
during  the  show? 

Focus  of  Color  Films 

"Duplitized"  prints  (Cinecolor,  Mag- 
nacolor,  Trucolor,  etc.)  pose  a  special 
problem  for  projectionists.  These  films 
carry  two  emulsions,  one  on  each  side 
of  the  film  base.  As  the  two  emulsions 
are  separated  by  about  0.00475  of  an 
inch,  it  is  impossible  to  bring  both  of 
them  to  a  sharp  focus  at  once;  and  the 
focus-difference  is  most  pronounced 
when  lenses  of  short  E.  F.  are  used.  The 
problem  is  further  complicated  by  the 
fact  that  the  two  superimposed  photo- 
graphic images  have  complementary 
colors  (red-orange  and  blue  in  some 
processes ;  red  and  blue-green  in  others) . 

Shall  the  focus  be  compromised  so 
that  red-orange  and  blue  images  are 
equally  out  of  focus;  or  shall  one  of 
these  images  be  focused  sharply,  ignor- 
ing the  other? 

The  writer's  opinion  is  that  the  less 
luminous  of  the  two  colors  be  focused 
sharply.  The  color  sensitivity  of  the 
human  eye  is  such  that  blue  appears  less 
luminous,  or  "darker,"  than  red,  and 
hence  provides  most  of  the  contrast  of 
the  colored  pictue.  The  blue  image, 
theerfore,  is  the  one  which  should  be 
brought  to  a  perfect  focus  on  the  screen 


Photomicrographs  reveal  the  appearance  of  the  silver  grains  in  the  film  emulsion  when  magnified 
to  the  extent  indicated  by  the  number  positioned  over  each  square. 


100 


1000 


5000 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


He  follows  motion  •  •  • 


HE  swings  the  camera  .  .  .  following 
motion,  keeping  the  object  of  interest 
always  frame-centered  .  .  .  there  you 
have  the  culmination  of  years  of  expe- 
rience— years  in  which  the  operative 
camera  man  learns  how  to  get  the  most 
from  his  equipment. 

But  he  learns,  in  those  years,  some- 
thing more — to  understand  the  prob- 
lems of  the  picture's  director  and  of 
the  director  of  photography.  From  this 


understanding  comes  his  great  abilitv 
to  interpret  their  wishes  creatively  .  .  . 
to  devote  his  technical  knowledge  to 
giving  them  what  they  want  from  every 
shot,  every  scene. 

Because  he  must  get  so  much  from 
every  shot,  his  dependence  on  film  of 
superior  quality  and  uniformity  is 
great.  That's  why  you'll  find  so  many 
operative  camera  men  using  the  family 
of  Eastman  motion  picture  films. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.Y. 

J.  E.  BRULATOUR,  INC.,  DISTRIBUTORS 
FORT   LEE     •     CHICAGO     •     HOLLYWOOD 


/  ^  MAGNA 


M. 


£W 


MAGNARC 


TRADE   MARK    REG 


1-KW  TO  70  AMPS 


"HY-AX"  ARC  MAGNET 

HY-LUMEN     REFLECTOR 


More  light  at  40  to  70  amperes  than  ever  thought  possible. 
.  .  .  Equals  and  excels  any  reflector  lamp  to  85  amperes,  whether 
they  be  unapproved  water-cooled  or  resurrected  hi-lows.  .  .  . 
Highest  ratio  of  screen  lumens  per  watt  consumed  at  the  arc. 
...  At  70  amperes,  with  a  projector  having  an  efficient  DISC 
type  revolving  shutter,  it  develops  the  maximum  white  light  that 
can  be  used  without  a  heat  filter. . . .  Operating  costs  under  these 
conditions  are  far  below  that  of  85-ampere  lamps. 

Magnarc  Lamps  assure  80%  side-to-center  (SMPE  Standard) 
screen  light  distribution,  not  a  deceptive  60%  or  "Hot  Center." 
.  .  .  They  are  all  Und.  Lab.,  Inc.  listed.  .  .  .  They  are  not  in- 
surance hazards.  .  .  .  They  are  and  have  been  for  years  "The 
Standard  of  Comparison"  and  "The  First  Choice"  of  large 
and  small  theatres,  drive-ins,  and  the  motion  picture  industry 
in  general! 


i  i 


ALWAYS  THE  FINEST,  ALWAYS 


1 1 


120-180  AMPERES 


TRADE   MARK   REG. 


NEW    MAGNETIC    STABILIZER 

This  modern  lamp  produces  all  the  light  there  is. 
...  It  is  the  standard  equipment  of  the  nation's  largest 
and  finest  theatres.  .  .  .  Used  by  90%  of  the  largest 
Drive-In  Theatres. 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  white  light  volume 
when  used  with  projectors  that  have  efficient  DISC 
type  revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions.  .  .  .  They  are  Und.  Lab.,  Inc. 
listed  and,  therefore,  not  insurance  hazards. 


1  1 


WHY    EXPERIMENT? 
-J.E.McAULEY  MFG. CD- 


/  i 


552-554    WEST  ADAMS    STREET 

CHICAGO   6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


if  the  clearest-appearing  colored   picture 
is  to  be  obtained. 

It  will  be  found  upon  examining  a 
duplitized  color  film  that  the  blue  image 
is  oriented  to  come  on  the  normal 
"emulsion  side"  of  the  film,  therefore 
the  focus  difference  between  dupHtized 
and  ordinary  black-and-white  prints  is 
not  as  great  as  some  people  think. 

Technicolor  is  a  horse  of  a  different 
color,  figuratively  speaking.  The  Tech- 
nicolor printing  process  is  unique,  being 
more  like  ordinary  printing  than  a 
photographic  process.  Three  black-and- 
white  positives,  called  "matrices,"  are 
chemically  treated  to  make  the  picture 
images  soak  up  colored  dyes.  The  three 
dye  images  are  transferred  to  the  pro- 
jection positive  by  simple  contact.  Exact 
register  of  the  yellow,  magenta,  and 
cyan  dye  images  on  the  projection  posi- 
tive is  absolutely  essential  to  the  clarity 
of  the  colored  picture  on  the  film. 

The  Technicolor  dyes  affect  the  gela- 
tin of  the  projection  positive  in  such  a 
way  that  the  Technicolor  image  is  a 
trifle  closer  to  the  film  base  than  is  an 
ordinary  silver  image.  The  result  is  that 
Technicolor  requires  a  slightly  different 
focus  than  do  b-and-w  subjects.  Failure 
to  heed  this  requirement  places  Techni- 
color under  a  severe  and  needless  handi- 
cap. Properly  projected.  Technicolor 
prints  provide  beautiful  and  entirely  satis- 
factory screen  images. 

The  chemical  constitution  of  the  film 
base  (nitrate,  diacetate,  triacetate,  ace- 
tate-propionate,  etc.)  has  no  effect  what- 
ever on  the  definition  of  the  projected 
picture.  Irregularities  in  the  thickness  of 
the  film  base,  however,  may  introduce 
focusing  troubles.  This  is  particularly 
true  in  the  case  of  duplitized  color  prints. 
[To  be  Continued] 

Forty-One   Years    Ago 

Open-Air  Theatre  in  Jacksonville,  Fla. 

The  opening  of  the  Summer  season  at 
Dixieland  Park  proved  a  remarkable 
success.  In  the  afternoon  fully  1500 
people  visited  the  park  and  enjoyed  the 
concert,  but  it  was  in  the  evening  that 
the  big  crowd  turned  out  to  see  the  open- 
air  moving  pictures. 

At  least  2500  people  were  on  the 
grounds  before  eight  o'clock,  and  the 
seating  capacity,  which  had  been  ar- 
ranged for  2000,  proved  entirely  inade- 
quate. Manager  Da  Costa  and  several  of 
the  directors  were  present,  and  it  was  at 
once  decided  to  arrange  seats  for  at  least 
1000  more  people. 

The  pictures  started  promptly  at  7:30, 
and  were  very  good.  They  could  be  seen 
nicely  at  a  distance  of  1000  feet  from  the 
elevated  canvas,  and  were  thoroughly  en- 
joyed by  the  immense  audience.  The  full. 
3000  feet  of  films  were  run  and  the  en- 
tertainment lasted  a  little  over  an  hour. 

Moving  Picture  World,  May  16,  1908 


Recent  Film  Technical  Advances 

Excerpts  from  a  Report  by  the  SMPE  Progress  Committee 


A  MODERATE  amount  of  new  re- 
cording equipment  was  introduced 
last  year  and  broad  progress  was  made 
in  the  widespread  use  in  this  country 
and  abroad  of  facilities  announced  in 
1947.  Supersonic-radio  playback  trans- 
mitters, with  miniature  receivers  and 
earphones  that  can  be  hidden  in  the  hair 
or  clothing  of  an  actor,  were  used  in 
Hollywood.  These  systems  proved  use- 
ful and  time-saving  in  playing  back 
records  or  for  cuing  the  actors  without 
interfering  with  recording  of  dialog. 

Some  daily  prints  of  picture  and  sound 
were  made  on  new  safety-base  stock  by 
Hollywood  laboratories,  but  its  use  as 
negative  stock  was  limited  by  availability. 
A  large  amount  of  engineering  effort  was 
devoted  to  magnetic  coatings  on  35-mm 
safety-base  film. 

Magnetic  Recording  Upsurge 

A  35-mm  magnetic  film  recorder  was 
introduced  by  RCA  for  either  portable 
or  studio  use.  Operating  at  18  inches 
per  second,  it  provides  for  wide-range 
recording  and  excellent  film  motion. 
Recording  and  playback  heads  are  pro- 
vided, and  an  erase  head  can  be  added 
if  desired.  The  bias  oscillator  and  play- 
back preamplifier  are  mounted  inside  of 
the  recorder. 

A  similar  film  recorder  was  introduced 
by  W.  E.  which  may  be  used  for  either 
the  magnetic  or  optical  method,  thereby 
facilitating  a  transition  period  or  re-re- 
cording operations  in  a  small  studio. 
High-quality  re-recording  and  review- 
room  machines  were  introduced  on  a 
field-trial  basis.  A  35-mm  magnetic  re- 
cording and  reproducing  unit  was  also 
demonstrated  by  Reeves  Sound. 

System's  Numerous  Advantages 

By  the  end  of  the  year  most  of  the 
studios  in  Hollywood  were  equipped  with 
at  least  one  35-mm  magnetic  recording 
machine  capable  of  operation  in  syn- 
chronism with  a  camera  or  projector. 
Some  studios  gained  additional  operating 
experience  through  the  use  of  tape  re- 
corders in  applications  where  synchron- 
ism was  not  essential. 

Extensive  laboratory  tests  and  limited 
studio  use  have  established  that  mag- 
netic recording  is  of  considerable  im- 
portance for  all  types  of  work  where 
re-recording  is  involved.  Excellent  fre- 
quency response  up  to  15.000  cycles  has 
been  obtained  with  an  inherent  ground- 
noise-to-signal  ratio  of  50  db  or  better. 
Ground  noise  does  not  appear  to  increase 
with  film  usage  and  the  magnetic  sound 
record  is  long-lived.  Other  advantages 
include  film  re-usage,  immediate  play- 
back,   elimination    of    lightfast    require- 


ments, and  simple  operation.  Important 
economies  can  be  realized  by  the  reduc- 
tion of  film  and  processing  costs. 

Re-recording  operations  at  Warner 
studios  were  simplified  and  reduced  in 
cost  by  first  combining  up  to  20  sound- 
effects  tracks  into  a  single  reel  of  mag- 
netic film.  In  the  final  re-recording  oper- 
ation two  magnetic  sound  tracks  were 
made  simultaneously:  one  containing  all 
the  speech,  music,  and  sound  effects,  and 
the  other  having  only  the  combined 
music  and  sound  effects.  The  latter  track 
is  then  available  for  making  16-mm  ver- 
sions and  for  the  use  of  the  foreign  de- 
partment in  combining  the  music  and 
sound-effects  track  with  a  foreign-speech 
track. 

16-mm  Recording,  Processing 

There  was  unusual  activity  in  the  16- 
mm  field  both  in  original  recording  and 
in  re-recording  from  35-mm  or  16-mm 
films,  which  resulted  in  better  sound 
quality  than  was  obtained  two  or  three 
years  ago.  The  recording  was  done  by 
using  negative-positive  methods  and 
equipment  previously  announced  or  by 
the  direct-positive  method  which  elim- 
inates the  necessity  of  making  a  negative. 

A  direct-positive  variable-density  re- 
cording technique  was  introduced  by 
W.  E.  in  which  a  24-kilocycle  bias  was 
appbed  to  the  light  valve  along  with 
the  audio  signal  to  reduce  distortion  and 
improve  the  volume  range. 

The  use  of  the  so-called  35-32-mm 
process  as  a  step  in  the  release  of  16-mm 
prints  increased  appreciably  during  the 
year.  It  employs  special  sound  negative 
film  35  mm  in  width  having  16-mm  per- 
forations along  each  edge. 

Two  re-recorded  sound  tracks  are 
placed  near  the  center  of  the  film  by 
recording  at  36  feet  per  minute  in  oppo- 
site directions,  and  then  processed  in 
standard  35-mm  developing  machines  of 
the  sprocketless  type.  Printing  is  done 
from  the  double-track  sound  negative 
along  with  the  picture  to  32-mm  release 
print  stock,  is  developed  by  standard 
positive  processing  except  for  rollers 
32  mm  in  width,  and  then  is  spbt. 

Visual  Sound  Reproduction 

This  general  method  has  the  advantage 
of  standard  35-mm  processing  equip- 
ment and  control  as  well  as  locating  the 
sound  track  in  the  center  of  the  film 
where  it  is  protected  from  rollers  and 
sprockets.  At  the  present  time  seven 
Hollywood  studios  can  do  this  type  of 
recording  and  at  least  four  laboratories 
the  processing. 

There  was  relatively  little  indoor 
theatre    construction    and    only    a    minor 


INTERNATIONAL  PROJECTIONIST 


August  1949 


amount  of  modernization  activity  in  the 
U.S.A.  last  year  (1948).  The  installa- 
tion of  soundheads,  amplifiers,  and 
modern  two-way  loudspeaker  equipment 
to  replace  outmoded  and  wornout  equip- 
ment continued  at  a  moderate  pace. 
Some  increase  in  modernization  was 
noted   toward  the  end  of  the  year. 

The  outstanding  1948  development  in 
the  35-mm  field  of  theatres  and  equip- 
ment was  the  enormous  increase  in  the 
number  of  drive-in  installations,  which 
at  the  end  of  the  year  were  variously 
estimated  to  number  somewhere  between 
800  and  1000. 

Part  of  the  popularity  of  the  drive-in 
is  due  to  the  now  almost  universal  use 
of  individual  in-car  speakers,  which  elimi- 
nate the  interference  and  sound-transit- 
time  problems  encountered  in  the  first 
drive-ins  using  central-speaker  equip- 
ment. Screen  "presence"  and  "illusion" 
are  generally  satisfactory  in  spite  of  the 
displacement  between  picture  and  speak- 
ers. 

High  Amperage  Poses  Problems 

Drive-in  theatre  screens  range  up  to 
65  feet  in  width.  To  put  a  reasonably 
satisfactory  picture  on  such  screens,  a 
trend  developed  toward  the  use  of  higher 
and  higher  powered  light  sources,  faster 
lenses,  and  filters  and  blowers  to  cool 
the  film  at  the  projector  aperture.  The 
use  of  high-intensity  arc  lamps  of  the 
condenser  type  burning  150  to  170  am- 
peres, continued,  and  reflector-type  lamps 
were  improved  and  their  operating  cur- 
rent ranges  were  increased.  Double- 
shutter  projector  mechanisms  were 
widely  used  in  drive-ins. 

Sound-equipped  designs  remained 
more  or  less  standard  except  for  use  of 
large  Class  B  output  amplifiers  to  de- 
liver the  considerable  amounts  of  audio 
power  required  by  the  hundreds  of  in- 
dividual speakers  of  relatively  low  effi- 
ciency in  the  average  installation.  Motio- 
graph  brought  out  multiple-amplifier 
systems,  with  each  amplifier  serving  only 
a  small  group  of  speakers  for  improved 
reliability  and  greater  emergency  pro- 
tection, and  also  developed  a  system  of 
lighting  for  the  speaker-junction  boxes 
to  reduce  collision  risks. 

Toward  the  end  of  1948  two  manu- 
facturers brought  out  speaker-heater 
combinations  to  extend  the  season  in 
temperate  climates  and  promote  comfort 
in  those  having  12-month  seasons,  but 
chilly  nights.  Heaters  dissipate  approxi- 
mately 250  watts  and  have  small  blowers 
to  distribute  the  heat  and  keep  surface 
temperatures  to  more  or  less  reasonable 
values. 

Broaden  Acetate  Film  Use 

During  1948  acetate  safety-base  35-mm 
film  for  release  prints  came  into  limited 
use,  principally  for  certain  types  of  color 
films.     The    performance    was   generally 


Accuracy  of  Unsteadiness  Test  Films 


MR.  R.  H.  CRICKS,  editor  of  Ideal 
Kinema  (London)  commented  on 
the  quality  of  unsteadiness  test  films.  In 
general,  his  comment  is  correct  as  far  as 
it  goes.  He  paints,  in  part,  a  good  pic- 
ture, but  he  is  not  a  finished  artist  be- 
cause he  has  omitted  a  number  of  im- 
portant brush  strokes. 

Mr.  Cricks  states:  "American  steadi- 
ness test  films  are  .  .  .  prints,"  and  he 
opines  that  prints  are  generally  unsatis- 
factory for  testing  for  steadiness  of  pro- 
jection. 

A  35-mm  steadiness  test  film  produced 
by  the  SMPE  is  a  negative-perforated 
safety  positive  film  which  has  low  shrink- 
age characteristics.  The  original  negative 
is  photographed  in  a  camera  known  to 
have  inherent  unsteadiness  of  the  order 
of  normal  tolerances  of  35-mm  negative 
perforations.  Prints  are  made  on  a  step- 
printer  with  closely-fitting  negative  regis- 
tration pins. 

Tolerance  to  Vanishing  Point 

The  measurable  print  unsteadiness  in 
the  vertical  direction  is  somewhat  less 
than  one-fifth  of  1%  of  the  picture  height, 
and  the  lateral  unsteadiness  is  about  the 
same  proportion  of  picture  width !  These 
errors  are  substantially  within  the  toler- 
ances for  most  35-mm  projectors.  This 
film  might  not  satisfy  the  exacting  re- 
quirements for  studio  process  projectors, 
but  it  should  and  does  serve  more  than 
adequately  for  theatre  projectors. 

Mr.  Cricks  mentions  a  special  per- 
forator which  he  has  used  which  punched 
a  hole  in  the  center  of  the  film  at  the 
same  time  that  the  perforations  were 
made,  the  purported  advantage  being  that 
"the  test  hole  was  necessarily  registered 
with  perfect  accuracy  with  the  feeding 
perforation." 

A  qualification  would  seem  to  be  in 
order  here,  for  it  is  obvious  that  anv  error 


in  the  perforating  of  the  film — that  is, 
from  one  punch  stroke  to  the  next — 
would  cause  unsteadiness  of  the  refer- 
ence hole  if  the  same  perforations  were 
not  used  to  register  the  film  in  the  pro- 
jector. This  holds  true  for  16-mm  as  well 
as  for  35-mm  film. 

Bearing  on  this  problem  is  the  very 
fine  unsteadiness  film  made  by  Bell  & 
Howell  Co.  which  is  practically  indepen- 
dent of  perforation  errors.  This  film  is 
described  in  detail  by  M.  G.  Townley  in 
the  SMPE  Journal  for  July,  1944.  Un- 
steadiness of  the  single  center  reference 
hole  alone  is  a  true  indication  of  pro- 
jector unsteadiness  only  when  the  pro- 
jector registers  with  the  same  perforation 
that  was  punched  with  the  reference  hole. 

Double-Check  on  B.  &  H.  Reel 

To  make  the  film  a  valid  test  for  un- 
steadiness in  projectors  which  register 
with  a  different  perforation,  Mr.  Townley 
has  added  a  second  reference  hole  on  the 
frameline,  punched  at  the  same  time  as 
the  preceding  sprocket  hole.  He  then 
uses  one  mirror  to  project  an  image  of 
the  center  reference  hole  and  another 
mirror  to  project  an  image  of  the  refer- 
ence hole  punched  in  the  center  of  the 
frameline  by  the  preceding  stroke  of  the 
perforator. 

Movement  between  these  two  reflected 
images  is  a  true  index  of  perforation 
errors,  and  movement  of  the 'pair  of  holes 
is  a  true  indication  of  projector  unsteadi- 
ness. Mr.  Townley  utilizes  round  h»les, 
just  as  Mr.  Cricks  did,  and  measures  un- 
steadiness with  a  ruler. 

The  SMPE  has  a  photographed  pattern 
that  permits  unsteadiness  to  be  gauged 
directly  in  percent  of  both  picture  height 
and  width.  This  would  appear  to  be  a 
simpler  method.  Perhaps  somebody  will 
some  day  apply  the  same  system  to  a 
16-mm  unsteadiness  test  film. 


satisfactory,  though  considerable  diffi- 
culties with  splices  were  observed,  pos- 
sibly because  projectionists  do  not  al- 
ways recognize  the  safety-base  film  and 
hence  do  not  use  the  special  splicing 
techniques  it  requires. 

No  relaxation  in  projection-room  safety 
requirements  was  reported,  which  is  to 
be  expected  so  long  as  any  nitrate  film 
is  in  common  use. 

Release  prints  generally  were  of  ex- 
cellent quality  with  respect  to  both 
sound  and  picture  during  the  year,  with 
the  exception  of  some  of  those  made  for 
reissued  pictures.  Sound  on  these  was 
substandard  in  quality,  and  cases  were 
reported    where    the    original    negatives 


were  apparently  so  badly  shrunk  that 
picture  frames  failed  to  fill  projector 
apertures  completely,  causing  light 
streaks  at  the  picture  borders. 

New  16-mm  Projection  Lenses 

There  was  a  slight  trend  toward  ar- 
rangements for  mounting  larger  pro- 
jector lenses  having  characteristics  which 
will  improve  picture  quality.  For  ex- 
ample, a  new  series  of  projection  lenses 
for  professional  16-mm  use  was  an- 
nounced by  Bausch  and  Lomb.  These 
Super-Cinephor  lenses  have  a  speed  of 
F:1.6  and  focal  lengths  of  two  to  four 
inches  in  half-inch  steps,  will  resolve  90 
lines  per  mm,  and  provide  practically 
uniform  screen  illumination. 


10 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


It 


's  the 


-a«fe. 


that  count 


i 


in  RCA  Theatre  Sound  Equipment 


Only  one  five-thousandths  of  an  inch  thick 
and  weighing  but  one  twenty-fifth  of  an 
ounce,  the  precision-engineered  speaker 
diaphragm,  illustrated  above,  has  amazing 
vibration-sensitivity,  combined  with  singu- 
lar sturdiness  . . .  hidden  values  that  count 


decisively  in  re-creating  all  sound  effects, 
from  the  whispering  wind  in  the  grass  to 
the  mighty  crescendo  of  a  symphony  or- 
chestra. This  is  one  of  many  reasons  why 
you  should  use  RCA  Theatre  Sound  Sys- 
tems in  your  theatre. 


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The  Great  Enigma:  The  Stereoscopic 

Perspective 


THE  Writer  is  aware  that  this  article, 
in  the  eyes  of  the  "experts,"  borders 
on  heresy — this  despite  the  fact  that 
the  stereoscopic  perspective  was  first 
postulated  by  the  celebrated  Helmholtz 
(1821-94).  This  postulation  was  widely 
attacked  and  ridiculed  even  though 
Helmholtz  made  highly  important  con- 
tributions to  stereoscopy. 

The  writer,  however,  felt  that  Helm- 
holtz was  right  and  devoted  many  years 
to  the  subject  in  order  to  find  a  suitable 
substitute  for  the  geometric  perspective. 

The  Geometric  Perspective 

The  geometric  perspective  is  univer- 
sally recognized  as  the  only  correct  and 
undistorted  one.  It  is  widely  used  in  the 
graphic  arts,  and  is  that  produced  by  the 
photographic  objective.  The  foremost 
task  confronting  a  lens  constructor  when 
calculating  a  new  objective  is  the  attain- 
ment of  this  perspective. 

Theoretically,  a  painter  who  desired  to 
make  a  picture  which  would  be  faithful 
to  the  laws  of  true  geometric  perspective 
would  have  to  undergo  quite  an  ordeal. 
After  choosing  the  point  from  which  he 
wished  to  depict  his  subject  he  would 
place  a  transparency  in  a  vertical  posi- 
tion between  this  viewpoint  and  the 
scene. 

An  assistant  then  would  clamp  the 
painter's  head  rigidly  facing  the  scene, 
after  which  the  latter  would  place  a  cov- 
ering over  one  of  his  eyes.  The  painter 
then  would  trace  exactly  the  outlines  and 
details  of  his  subject  on  the  transparency. 
If  the  tracing  were  done  accurately,  the 
finished  picture  would  possess  true  un- 
distorted geometric  perspective. 

Careful  consideration  of  this  proce- 
dure discloses  some  highly  interesting 
facts.  Evidently,  clamping  of  the  head 
would  allow  but  a  single  motion,  rotation 
of  the  eyeball,  which  is  necessary  in  order 
to  achieve  sharp  focusing  of  details.  Ro- 
tating the  eyeball  in  such  a  manner  per- 
mits scanning  all  details  individually 
and  successively  by  the  fovea  lutea* 

The  eyeball,  and  therefore  the  eyelens 
and  the  fovea  lutea,  may  be  rotated  with 
infinite  freedom  in  all  directions  to  make 
this  scanning  possible.  However,  since 
the  eye  proper  is  held  stationary,  it  is  ob- 
vious that  the  center  of  the  eyeball  be- 
comes the  point  from  which  the  scene  is 
actually  observed.  The  artist  would  trace, 
therefore,  not  the  image  cast  on  his  retina 
by  the  eyelens  (which  is  the  image  we 
see    and   experience    at    all    times)    but 


*  The  only  point  of  the  retina,  directly  in  the  axis 
of  vision,  where  sharp  focusing  of  minute  details  can 
be  accomplished. 


By  THEODORE    NAKKEN 

Teacher,  lecturer,  inventor,  Theodore  Nakken 
has  had  a  long  and  varied  career  in  the  elec- 
tro-optico-mechanical  fields,  ranging  from 
wireless-controlled  vessels  and  torpedoes  for  the 
Czarist  Russian  government  to  numerous  pat- 
ents in  the  sound  picture  field.  Outstanding 
among  the  latter  was  a  photoelectric  cell  cir- 
cuit which  figured  prominently  in  patent  liti- 
gation in  the  1930's. 

rather  the  successive  scanning  positions 
of  his  fovea  lutea  as  details  were  being 
focused  thereon. 

From  this  it  follows  that  the  foveal 
image-in-time,  which  would  be  traced  in 
projection  on  the  transparency,  is  only 
half  the  size  of  the  image  normally  cast 
by  the  eyelens.  Moreover,  as  correctly 
stated  by  Helmholtz,  its  center  of  per- 
spective in  the  center  of  the  eyeball. 

The  unavoidable  conclusion  to  be 
drawn  is  that  the  artist  would  create  in 
his  tracing  operation  an  enlargement  of 
an  image  that  he  never  "saw"  in  his  life, 
because  it  would  exist  only  in  time,  and 
one  that  he  could  not  possibly  ever  "see." 
The  picture,  however,  would  have  true, 
undistorted  geometric  perspective. 

Painters  greeted  joyfully  the  invention 
of  the  camera  obscura  because  it  enabled 
them  to  trace  the  outlines  of  scenes  on  a 
screen  upon  which  an  image  of  the  scene 
was  cast  by  a  stationary  lens.  This  image, 
incidentally,  has  the  same  perfect  geo- 
metric perspective  as  the  image  produced 
by  a  stationary  single  eye. 

Geometric  Perspective  Unsatisfactory 

Formulation  of  the  laws  of  perspective, 
begun  toward  the  end  of  the  Renaissance, 
represented  a  tremendous  stride  forward 
in  picturization.  Nevertheless,  they  were 
never  adequate  for  the  attainment  of 
that  which  was  actually  needed.  Leon- 
ardo Da  Vinci  (1452-1519)  stated  cor- 
rectly that  in  order  to  appreciate  fully 
a  geometrically-constructed  picture,  it 
should  be  viewed  with  a  single  eye  held 
in  the  identical  position  as  described 
previously  in  the  example  of  the  painter 
producing  the  tracing.  In  that  position 
alone  would  the  tracing  become  an  ac- 
ceptable substitute  for  reality. 

The  growing  appreciation  of  the  im- 
portance of  correct  perspective  was  natu- 
rally reflected  first  in   the   graphic   arts 


field,  for  paintings,  etchings  and  engrav- 
ings. Collectors  would  view  steel  engrav- 
ings in  a  so-called  viewing  box  in  which 
a  picture  holder  could  be  moved  forward 
and  backward  until  the  best  perspective 
was  attained.  The  important  point  here, 
however,  is  that  the  viewing  was  done 
with  a  single  eye  through  a  small  hole  in 
the  rear  of  the  box,  thus  insuring  that  the 
eye  was  positioned  at  the  exact  center 
of  perspective. 

In  Europe  there  still  are  many  different 
picture-viewing  devices  on  the  market; 
while  the  American  version  is  the  "scop- 
er"  in  which  Leica-size  pictures  or  trans- 
parencies may  be  viewed,  often  with 
effects  of  startling  realism  or  even  three- 
dimensionality. 

Very  few  people  today  are  aware  of 
the  fundamental  requisites  for  viewing 
pictures  at  their  best.  Every  day  we  see 
pictures  side  by  side  which  for  real 
enjoyment  should  be  viewed  monocularly 
from  wholly  different  distances.  Thus  the 
geometric  perspective  fails  entirely  to 
portray  reality  in  a  natural  way  with 
depth  and  solidity.  This  applies  also  to 
motion  pictures.  The  inadequacy  of  the 
geometric  perspective  is  felt  keenly  by 
all  workers  in  the  graphic  arts  field. 

Advent  of  the  Stereoscope 

The  invention  of  the  stereoscope  in 
1832  seemed  to  hold  great  promise.  Here 
two  pictures  of  the  same  subject  are  pro- 
duced by  means  of  two  cameras  spaced 
horizontally  6.5  cm  apart,  a  distance 
equal  to  the  average  interpupillary  sepa- 
ration of  the  eyes.  These  pictures,  of 
course,  are  slightly  different  in  the  same 
way  that  the  two  images  on  the  retinas 
of  the  eyes  are  slightly  different  from 
each  other. 

Just  as  a  single  picture  viewed  mono- 
cularly can  be  an  adequate  substitute  for 
reality,  so  do  these  two  pictures  substi- 
tute for  that  which  two  eyes  would  see  in 
a  given  scene — provided,  of  course,  that 
the  left  and  the  right  eyes  view  only  the 
left  and  right  pictures,  respectively. 
When  these  two  pictures  are  viewed  un- 
der proper  conditions,  the  effect  is  one 
of  startling  realism. 

Why  should  this  be  so? 

In  normal  vision  scenes  are  imaged  by 
the  eyelenses  on  the  two  retinas,  the  sen- 
sitive elements  of  which  are  individually 
connected,  by  means  of  nerve  strands,  to 
the  visual  perception  center  of  the  brain, 
often  called  the  cortinal  retina.  Should 
these   interconnecting  nerve    strands    be- 


INTERNATIONAL  PROJECTIONIST 


August  1949 


13 


come  severed  or  diseased,  partial  or  even 
total  blindness  results,  even  if  both  eyes 
appear  completely  normal. 

In  the  cortical  retina  the  two  images 
merge  and  are  impinged  on  the  con- 
sciousness as  a  single  image  instead  of 
two  separate  and  distinct  images.  This 
ability  of  the  cortical  retina  or  brain 
appears  miraculous  when  contrasted  with 
the  results  obtained  when  other  means 
are  employed  to  attain  the  same  end — a 
jumbled,  confusing  double  picture. 

In  the  stereoscope  two  pictures  are 
presented  to  the  eyes  under  almost  iden- 
tical circumstances,  as  when  Nature  is 
normally  observed  binocularly.  Obvious- 
ly, the  same  process  of  merging  two 
images  with  identical  spatial  sensations 
occurs  in  the  cortical  retina.  Braving 
further  criticism,  the  writer  is  of  the 
opinion  that  that  which  happens  in  this 
process  is  not  miraculous  at  all  but  is 
most  natural  and  to  be  expected,  and, 
further,  that  no  unknown  factors  affect 
a  simple  explanation  of  the  merging 
process. 

Stereoscope  Viewing  Process 

It  has  been  established  definitely  that 
the  eye  possesses  only  a  single  spot  in 
the  retina  where  sharp  focusing  is  pos- 
sible, the  fovea  lutea,  which  serves  as  a 
scanning  device  to  so  sweep  a  scene  as 
to  cause  individual  sharp  imaging  of  de- 
tail. 

Immediately  outside  the  fovea  there  is 
no  sharpness  of  the  retinal  image.  For 
example,  if  the  reader  will  focus  sharply 
on  either  dot  of  the  following  colon 
—  :  — ,  he  will  perceive  that  the  other 
dot  is  out  of  focus  and  has  lost  its  sharp 
outline. 

Clearly,  then,  when  viewing  a  scene 
one  sees  only  a  single  detail  with  great 
acuity,  the  surroundings  becoming  pro- 
gressively more  hazy  with  distance  from 
that  detail.  In  fact,  by  simply  concen- 
trating on  one  object  in  a  scene,  every- 
thing surrounding  that  object  becomes 
hazy  in  outline  to  the  point  of  non-recog- 
nition. The  fact  that  we  seem  to  see  the 
entire  scene  sharply  is  due  to  the  very 
rapid  scanning  motion  of  the  eye  which 
brings  successive  details  into  sharp  focus. 

When  a  scene  is  viewed  binocularly,  the 
foveas  of  both  eyes  scan  the  same  details 
simultaneously.  The  areas  immediately 
surrounding  these  details  are  naturally 
hazy  in  both  eyes,  the  merging  of  these 
hazily-seen  surroundings  resulting  in  a 
new  impression  with  a  "mixed"  perspec- 
tive, the  confusion  and  haziness  of  which, 
however,  is  not  much  greater  than  in  each 
retinal  image  separately. 

It  seems  clear,  therefore,  that  while 
details  are  seen  sharply  and  as  well- 
defined  entities,  they  are  surrounded  by 
a  vaguely-perceived  background  which  is 
a  mixture  of  the  perspectives  seen  by 
the  eyes  separately.  This  hazy,  mixed  per- 


spective, and  the  doubling  effects  occur- 
ring farther  away  from  the  sharp  foveal 
impressions,  are  experienced  as  the  stereo- 
scopic perspective.  The  sharply  observed 
cortical  image,  composed  of  details 
viewed  binocularly,  is  assembled  in  an 
amazingly  fast  manner. 

Binocular  Vision 

It  is  the  writer's  opinion  that  the  binoc- 
ular sensation  of  depth,  solidity  and 
space  results  from  the  fact  that  the 
sharply-seen  cortical  image  is  not  a  mer- 
ger of  two  dissimilar  images  but  is  rather 
an  image  built  up  in  the  manner  de- 
scribed from  details,  each  one  of  which 
was  seen  in  merged,  stereoscopic  sur- 
roundings. 

The  passing  years  witnessing  no  ad- 
vance in  the  understanding  of  the  nature 
of  stereoscopic  vision  as  such,  there  de- 
veloped the  conviction  in  the  minds  of 
workers  in  the  art  that  three-dimensional 
vision  could  be  attained  only  by  the  mer- 
ger in  the  brain  of  two  separate  parallax- 
ially-different  images.  They  ignored  the 
simple  fact  that  one-eyed  drivers  appar- 
ently are  as  good  judges  of  space  and 
distance  as  are  two-eyed  drivers,  and  that 
there  are  first-rate  tennis  players  and 
other  athletes  who  hit  the  ball  consist- 
ently, despite  the  lack  of  stereo  vision. 

Many  years  ago  the  writer  coined  the 
term  "trimensional  perspective,"  which 
will  be  encountered  several  times  herein, 
and  the  characteristics  of  which  may  be 

FIGURE  1 


recognized  and  derived  by  diligent  con- 
sideration of  Fig.  1. 

This  diagram  differs  from  those  used 
in  optical  texts  in  which,  generally,  two 
colossal  eyes  are  shown  looking  cross- 
eyed at  a  very  small  object  at  a  distance 


about  equal  to  or  somewhat  less  than  the 
interpupillary  distance  of  the  eyes. 

Graphical  Representation 

In  Fig.  1  two  eyes,  1  and  2  represented 
by  dots  are  placed  rather  close  together 
and  look  at  objects  A,  B  and  C  in  a  scene 
placed  at  an  appreciable  distance  from 
the  eyes.  The  figure  represents  a  top  view 
of  eyes  and  scene;  the  objects,  shown  as 
circles,  might  be  three  round  tables  or 
have  any  other  conceivable  shape. 

When  both  eyes  look  toward  object  A, 
it  is  clear  that  left  eye  1  will  see  more 
of  this  object  on  the  left  side,  and,  con- 
versely, that  right  eye  2  will  see  more  of 
this  object  on  the  right  side.  This  is  ap- 
parent from  the  lines  of  vision  drawn 
through  the  two  eyes  tangent  to  object  A. 
Obviously,  the  two  extreme  lines  of  vision 
embrace  more  of  the  object  than  the  lines 
of  vision  of  either  one  of  the  two  eyes. 
When  now  we  extend  these  two  extreme 
lines  of  vision,  we  find  that  they  cross 
each  other  at  point  a  located  behind  the 
eye  base  and  on  the  side  of  the  centerline 
opposite  to  that  in  which  the  object  is 
located. 

How  Objects  Are  Seen 

Now,  if  a  single  eye  were  placed  at  this 
crossover  point  a,  it  would  view  object 
A  while  embracing  as  much  of  its  girth 
as  do  the  two  eyes  1  and  2.  Thus  point  a 
may  be  designated  the  equivalent  viewing 
point  for  eyes  1  and  2  with  respect  to 
object  A,  because  from  there  a  single  eye 
sees  the  object  along  the  extreme  lines  of 
vision  of  the  two  eyes. 

The  extreme  lines  of  vision  for  the  two 
eyes  viewing  object  B  reveal  the  existence 
of  another  equivalent  viewing  point,  b; 
and  similarly  we  find  an  equivalent  view- 
ing point  c  for  object  C. 

Looking  at  the  lines  of  vision  from 
these  equivalent  viewpoints,  and  at  the 
lines  of  vision  from  either  one  of  the 
eyes,  we  find  that  in  each  case  the  object 
obtends  an  angle  which  is  smaller,  in  the 
case  of  the  equivalent  viewpoints,  than 
in  the  case  of  either  eye  viewing  a  par- 
ticular object.  Hence,  as  the  angle  ob- 
tended  by  an  object  is  the  sole  factor 
which  determines  its  linear  dimension  in 
an  image,  it  is  clear  that  all  objects  are 
seen  narrower  in  binocular  than  in  mon- 
ocular viewing. 

The  word  "narrower"  is  used  advisedly 
because  vertically  both  eyes  are  on  the 
same  level  and  thus  see  the  vertical  char- 
acteristics of  an  object  (and  space)  un- 
der identical  angles.  Therefore,  as  far  as 
vertical  phenomena  are  concerned,  we 
might  just  as  well  have  a  single  eye  at 
point  3. 

Pausing  here  a  moment,  we  might  con- 
sider that  in  a  single  stroke  we  have  un- 
raveled part  of  the  enigma  of  binocular 
vision.  We  find  that  in  the  perspective 
created  binocularly  there  is  but  a  single 


14 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


vertical  center  of  vision  or  perspective; 
while  there  is  a  plurality  of  horizontal 
centers  of  vision,  these  being  the  equiva- 
lent viewing  points  for  the  two  eyes  for 
each  and  every  object  in  a  scene. 

Narrowing  of  Objects 

We  find,  further,  that  in  the  binocular 
perspective  objects  are  imaged  narrower 
than  in  the  geometric  perspective,  be- 
cause horizontally  these  objects  obtend 
smaller  angles  than  those  obtended  in 
the  monocular,  geometric  perspective. 
We  know  also  that  objects  to  the  right  of 
center  in  a  scene  are  seen,  in  the  binocu- 
lar perspective,  from  the  left  of  center; 
while  objects  in  the  left  of  the  scene  are 
viewed  from  the  right. 

However,  the  difference  in  angles  ob- 
tended in  the  two  different  kinds  of  per- 
spective may  become  so  small  as  to  be 
insignificant.  This  happens  when  this 
difference  becomes  less  than  the  angle 
of  the  retinal  curve  obtended  by  a  single 
visual  element,  because  then  no  differ- 
ence in  dimension  can  be  observed  any- 
more, according  to  the  teachings  of  con- 
ventional stereoscopists.  This  occurs 
when  light  rays  from  the  objects  reach 
the  eyes  substantially  as  parallel  rays, 
which  happens  with  increase  in  distance 
of  the  objects. 

Thus  at  the  "critical  stereoscopic  dis- 
tance" this  difference  in  angle  obtended 
disappears,  and  the  binocular  perspective 
merges  into  the  geometric  perspective. 
The  narrowing  down,  or  slenderizing,  of 
the  images  of  objects  is  strongest  for 
nearby  objects,  decreases  gradually  with 
distance,  at  last  to  become  zero. 

How  Interspaces  Are  Seen 

Returning  to  Fig.  1,  we  now  will  con- 
sider another,  and  extremely  interesting, 
fact.  Between  objects  A  and  B  there  is 
a  space,  designated  by  D;  and  between 
objects  B  and  C  there  is  a  space,  E.  Close 
inspection  reveals  that  the  two  eyes,  look- 
ing through  these  interspaces  at  the  back- 
ground, again  do  so  binocularly  and 
show,  once  more,  'extreme  lines  of  vision. 

For  space  D  these  extreme  lines  of 
vision  are  the  line  drawn  from  left  eye  1 
tangent  to  the  left  side  of  object  B,  and 
the  line  drawn  from  right  eye  2  tangent 
to  the  right  side  of  object  A.  These  two 
extreme  lines  of  vision  cross  each  other 
at  point  d,  which,  therefore,  is  the  point 
from  which  a  single  eye  would  look 
through  the  interspace  between  objects 
A  and  B,  in  tho  tnoe  manner  as  do  the 
two  eyes  1  and  2. 

Spaces  Seen  Wider 

Point  d,  therefore,  may  be  designated 
as  the  equivalent  point  of  vision  for  the 
eyes  1  and  2,  as  regards  interspace  D. 
For  space  E  we  find,  in  an  exactly  similar 
manner,  an  equivalent  viewpoint  e,  from 
which  a  single  eye  would  see  this  space 


in  the  same  manner  as  do  the  two  eyes 
1  and  2. 

In  the  case  of  these  equivalent  view- 
points for  interspace  we  find,  however, 
that  they  are  located  in  front  of  the  eye 
baseline.  Moreover,  we  see  that  the  an- 
gles obtended  by  the  interspace  from 
these  points  are  larger  than  those  from 
either  one  of  the  two  eyes.  This  means, 
of  course,  that  the  interspaces  are  seen 
in  widened  proportions,  in  contradistinc- 
tion to  the  slenderizing  effect  we  found  to 
occur  with  objects.  Again,  the  term 
"widening  of  the  interspaces"  is  used 
advisedly,  because,  vertically,  there  still 
is  no  change  in  proportions,  as  vertically 
the  eyes  are  on  the  same  level. 

Expressed  simply,  we  find  that  in  bin- 
ocular vision  we  look  through  the  inter- 
spaces between  objects  from  a  multitude 
of  points  located  in  front  of  the  eye  base, 
and  under  wider  angles,  so  that,  binocu- 
larly, we  are  enabled  to  see  more  of  the 
background  than  is  possible  with  either 
eye. 

Again,  this  increase  of  angle  with 
which  in  binocular  vision  we  look 
through  interspaces,  decreases  with  dis- 
tance until,  beyond  the  critical  distance 
discussed  previously,  the  difference  in  an- 
gles obtended  by  spaces  becomes  equiv- 
alent to  zero.  Hence  this  cause  for  stereo 
vision  also  ceases  to  exist  at  the  critical 
distance. 

We  are  now  in  a  position  to  define 
clearly  the  difference  between  the  per- 
spective seen  in  binocular  vision  and  the 
geometric,  or  monocular,  perspective. 

The  Stereoscopic  Perspective 

In  the  latter,  there  is  but  a  single  view- 
ing center  or  center  of  perspective,  i.e., 
the  center  of  the  eyeball,  or  the  objective 
of  a  camera;  while  the  former  possesses 
three  different  kinds  of  viewpoints:  first, 
a  single  center  of  perspective  in  the  ver- 
tical sense,  which  may  be  said  to  be 
located  at  a  point  midway  between  the 
two  eyes;  second,  a  group  of  viewpoints 
for  objects,  located  behind  the  eye  base- 
line on  the  opposite  side  of  the  center- 
line  to  that  on  which  the  objects  are 
located;  third,  a  group  of  viewpoints  lo- 
cated in  front  of  this  baseline  from  which 
interspaces  are  viewed,  on  the  same  side 
of  the  center  line  as  these  interspaces 
themselves. 

It  follows  that  as  a  result  of  the  widely 
different  locations  of  these  various  view- 
ing points,  the  binocular  perspective  is 
totally  different  from  the  monocular,  geo- 
metric perspective.  As  was  shown,  objects 
are  slenderized,  by  a  given  percentage, 
which  is  greatest  for  nearby  objects  and 
decreases  with  distance.  Conversely,  in- 
terspaces are  widened,  by  a  given  per- 
centage, which  again  is  greatest  for 
spaces  between  nearby  objects  and  again 
decreases  with  distance.  Beyond  the  criti- 
cal stereoscopic  distance,  however,  both 


objects    and    interspaces    are    seen    with 
the  geometric  perspective. 

'Looking  Around'  Objects 

Expressing  these  facts  differently:  it  is 
often  stated  that  when  looking  at  Nature 
or  in  the  stereoscope,  we  "look  around" 
objects  in  the  foreground.  Of  course,  as 
the  distance  of  these  objects  increases, 
this  "looking  around"  effect  decreases 
and  gradually  disappears,  to  become  zero 
at  the  critical  distance. 

Now,  if  one  looks  around  an  object  in 
the  foreground,  one  must  see  more  of  the 
background:  Fig.  1  shows  that  this  is 
exactly  what  happens,  due  to  the  slender- 
izing of  foreground  objects  and  the  loca- 
tion of  the  interspace  viewing  points, 
from  which  "more"  of  the  background 
is  visible  than  from  the  location  of  either 
one  of  the  eyes. 

Between  the  extreme  narrowing  down 
of  objects  and  widening  of  interspaces 
and  the  geometric,  monocular  aspect  be- 
yond the  critical  distance,  there  exist,  of 
course,  an  infinite  number  of  gradations. 
In  practical  terms  this  means  that,  for 
instance,  when  a  person  is  seen  at  a  dis- 
tance of  10  feet  he  appears  more  slender 
than  when  seen  at  20  feet,  and  that  at 
20  feet  he  appears  to  be  more  slender 
than  when  seen  at  50  feet  distant;  while 
after  the  critical  distance  is  reached,  the 
person  is  seen  in  the  proportions  which, 
in  the  geometric  perspective,  obtain  at 
any  and  all  distances. 

It  is  quite  evident,  of  course,  that  the 
facts  here  enumerated  lend  themselves  to 
exact  mathematical  analysis.  Taking  the 
interpupillary  distance  at  an  average  of 
6.5  cm,  the  percentage  of  slendering  ef- 
fect may  be  calculated  for  any  chosen  dis- 
tance, as  may  the  opening  up  of  the 
interspacings  in  the  binocular  image. 

The  Double-Image  Effect 

There  is  one  special  case  to  be  consid- 
ered in  connection  with  the  stereoscopic 
perspective,  relating  to  what  happens 
when  very  narrow  objects  are  seen  at  an 
extremely  short  distance.  Such  an  object 
is  shown  in  Fig.  1  at  F.  Obviously,  in 
order  to  view  this  object  sharply  bin- 
ocularly,  the  eyes  must  assume  a  cross- 
eyed position.  When  they  do  this,  the 
background  becomes  at  once  jumbled 
and  doubled  up.  If,  however,  one  focuses 
the  eyes  on  an  object  in  the  background, 
the  object  is  projected  into  the  back- 
ground twice.  This  is  the  case  shown  in 
Fig.  1. 

This  fact  can  be  easily  proven  by  a 
simple  experiment.  While  facing  a  room, 
for  instance,  one  holds  a  pencil  in  verti- 
cal position  in  front  of  the  eyes  and 
focuses  on  it.  At  once  the  doubling  up 
and  jumbling  of  the  room  becomes  ap- 
parent. When  then  the  eyes  are  focussed 
on  any  one  object  in  the  room  in  the 
(Continued  on  page  23) 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


15 


IN  THE 


SPOTLIGHT 


By 

HARRY 

SHERMAN 


Recession  vs.  Reissues.  The  never-end- 
ing gab  in  the  trade  and  lay  press 
and  over  the  air  about  the  "recession" 
which  has  hit  the  motion  picture  business, 
particularly  the  theatre  field;  the  sad 
tale  of  a  friend  of  ours  who  until  recently 
was  an  inveterate  moviegoer,  and  a 
couple  of  incidents  dredged  up  from  our 
own  memory  dovetail  nicely  to  point  up 
one  of  the  most  asinine  practices  of  the 
great  minds  (in  a  cunning,  perfidious 
sort  of  way)  which  direct  the  affairs  of 
this  industry  of  ours. 

Our  friend's  story,  related  in  burning 
words,  recounts  his  experiences  which 
goaded  him  into  keeping  tabs  over  a 
period  of  eight  weeks  on  a  theatre  in 
his  neighborhood  catering  to  middle- 
class  patronage — a  theatre  seating  about 
700  which,  incidentally,  is  nicely  appoint- 
ed throughout,  spotlessly  clean,  comfort- 
ably seated,  courteously  staffed  and  air- 
conditioned. 

Over  an  eight- weeks  period  during 
June  and  July,  reports  our  friend,  this 
theatre  gave  over  24  of  its  playdates  to 
reissues  of  varying  vintages  extending 
from  1935  to  several  years  ago!  This 
without  a  word  of  explanation  in  their 
trailers,  printed  programs  or  lobby  dis- 
plays— and,  naturally,  at  the  regular  60c 
admission  charged  for  current,  although 
third-run.  offerings. 


The  theatre  management  did  make  a 
publicity  fuss  when  it  reseated  the  bal- 
cony, dubbed  it  a  "loge"  and  upped  the 
price  therefore  a  dime  to  70c. 

Nor  is  this  the  whole  story.  Sound  re- 
production is  very  poor  in  most  reissues 
because  of  the  shrinkage  of  the  negative. 
So  bad  is  this  shrinkage  in  some  cases 
that  picture  frames  in  positive  prints  fail 
to  fill  the  projector  aperture,  resulting  in 
light  streaks  at  the  screen  borders! 

As  of  August  1,  Columbia  Pictures 
Corp.  placed  into  general  release  no  less 
than  43  reissues.  Multiply  this  figure,  for 
a  seven-month  period,  by  only  the  Big  5 
distributors,  and  draw  your  own  conclu- 
sions. Nor  is  this  condition  confined  to 
the  New  York  Area:  there  were  18  re- 
issues in  the  Chicago  area  during  one 
month,  July! 

Maybe  this  isn't  the  most  important 
reason  why  the  movie  theatre  is  losing 
its  regular  customers,  but  to  our  mind  it 
represents  42% — the  reissue  percentage 
— of  the  reason. 

P.  S.  Our  friend  is  no  longer  a  regular 
moviegoer,  and,  possibly,  neither  are  the 
numerous  people  who  have  heard  him 
blast  the  industry. 

•  Our  good  friend,  Z.  A.  Sax,  business 
manager  for  Local  159,  Portland,  Ore., 
reports  the  satisfactory  settlement  of  all 


SCENE  AT  THE  RECENT  TMA  GRAND  LODGE  MEETING  IN  NEW  YORK  CITY 


In  the  usual  order.  Sec. -Treas.  Phil  Hitter,  Lodge  67,  Long  Island;  Frank  Galluzzo,  Lodge  4,  Chicago, 

who  is  shown  presenting  an  honorary  life  membership  in  the  Grand  Lodge  to  Harry  Sherman,  of  IP; 

President  William  Noon,  Lodge  1,  New  York  City;  IA  President  Dick  Walsh,  honorary  member  of 

Grand  Lodge,  and  J.  Dwyer,  Lodge  1,  New  York  City. 


wage  negotiations  with  the  exhibitors  in 
his  jurisdiction.  Increases  ranging  from 
10  to  20c  per  hour  were  agreed  upon, 
with  all  increases  retroactive  to  February 
1949.  Orin  Jacobsen,  IA  representative, 
assisted  Local  159  officials  in  the  negotia- 
tions. 

•  Bob  Dennis  and  Gene  Muller,  mem- 
bers of  San  Antonio  Local  407,  report 
excellent  business  at  their  new  drive-in 
theatre,  The  Variety. 

•  John  Q.  Bluenose  stalked  the  town  of 
Hattiesburg,  Miss.,  recently  when  the 
city  fathers  suddenly  were  "inspired"  to 
enforce  the  long-dormant  Blue  Laws  by 
the  wholesale  arrests  of  theatre  employes 
found  working  after  6  p.  m.  on  Sundays. 
Every  hour  the  police  appeared  at  the 
theatres  and  hustled  off  the  staff  to  the 
hoosegow,  only  to  have  standby  crews 
immediately  step  into  the  breach  and 
keep  the  shows  going. 

Although  the  shuttle  service  between 
theatres  and  the  police  station  was 
marked  by  good  nature  on  both  sides,  the 
exhibitors  finally  got  tired  of  paying  fines 
and  filing  briefs  and  threw  in  the  sponge. 
Exhibitors  promise  that  these  Blue  Laws 
will  be  repealed — and  soon. 

•  Congratulations  to  Harry  Abbott,  pres- 
ident of  Philadelphia  Local  307,  on  the 
graduation  of  his  son,  Frank  H.,  from 
the  Temple  University  Law  School. 

•  We  were  very  much  interested  in  the 
statement  released  by  Republic  Pictures 
Corp.  in  which  they  report  a  net  profit  of 
$504,456.77  for  the  28  weeks  ending 
April  30,  1949,  after  taxes.  The  net  profit 
for  a  similar  period  in  1948  was  $236,- 
832.85. 

Reconcile  these  figures,  if  you  can, 
with  Republic's  cries  of  distress  a  few 
months  back  when  they  sought  long  and 
strenuously  to  cut  down  projectionist 
manpower  in  their  New  York  City  pre- 
view studio.  'Twas  ever  thus,  and  likely 
always  will  be. 

•  Bert  Sanford,  director  of  sales  for 
Altec  Service  Corp.  for  the  past  20  years 
and  member  of  the  25-30  Club,  has  been 
appointed  general  sales  manager  for  the 
ABC    Vending    Corp.    The    ABC    outfit, 


16 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


which  is  headed  by  CharJes  L.  O'Reilly, 
former  theatre  exhibitor  in  New  York 
City,  owns  the  various  candy  and  pop- 
corn machines  now  an  integral  part  of 
motion  picture  theatre  lobbies. 

•  Canadian  Locals  302  (Calgary)  and 
371  (Edmonton)  have  joined  forces  to 
fight  the  exhibitors'  efforts  to  reduce  the 
projection  room  manpower  in  the  Prov- 
ince of  Alberta.  We  were  privileged  to 
see  a  copy  of  the  brief  prepared  by  these 
Locals,  and  we  congratulate  them  for  the 
excellent  manner  in  which  they  presented 
their  story.  The  case  is  now  pending  be- 
fore the  Provincial  authorities,  and  the 
officers  and  members  of  both  Locals  are 
very  optimistic  as  to  the  outcome. 

•  An  eye  operation  bedded  our  good 
friend,  Joe  Nuzzolo,  Sr.,  president  of  Bos- 
ton Local  182.  Several  weeks  rest  put  Joe 
in  shape  again,  and  he  is  now  back  on 
the  job  as  bright  and  chipper  as  ever. 

•  Bob  Gellatly  57,  secretary-treasurer 
for  many  years  of  Local  85,  Ottawa,  Can- 
ada, died  recently  after  a  brief  illness. 
For  the  past  seven  years  he  was  a  super- 
visor with  the  National  Film  Board,  and 
previous  to  that  he  worked  at  the  Avalon 
Theatre  in  Ottawa. 

•  Not  infrequently  the  gracious  gesture 
recoils  on  its  maker  with  disastrous  re- 
sults, as  was  demonstrated  by  Tom 
Neathery,  old-line  member  of  Local  384, 
Hudson  County,  N.  J.,  and  a  standup 
member  of  the  25-30  Club. 

While  visiting  his  sister  in  Virginia, 
Tom,  characteristically,  decided  to  in- 
stall the  house  window  screens.  With 
only  two  screens  to  go,  Tom  fell  from  a 
ladder  and  incurred  six  broken  ribs  and 
an  injured  shoulder.  Tom  is  on  the  mend 
now,  but  he  entertains  no  notions  of  go- 
ing into  the  contracting  business — at  least 
not  in  Virginia. 

•  The  TMA  (Theatrical  Mutual  Asso- 
ciation) held  its  1949  meeting  last  month 
at  the  Claridge  Hotel,  New  York  City. 
Ambitious  plans  have  been  made  for  re- 
vitabzing  this  organization,  once  the  out- 
standing association  of  mechanical  and 
technical  workers  in  the  amusement  field. 
During  the  past  few  years  many  new 
Lodges  have  been  formed  throughout  the 
country  and  the  membership  rolls  have 
increased  considerably. 

Several  hundred  members  and  guests 
were  present  at  the  obbgation  of  the 
newly-elected  Grand  Lodge  officers. 
Among  the  invited  guests  were  IA  Presi- 
dent Walsh;  Judge  Joseph  McKinney,  a 
boyhood  friend  of  the  new  president,  Bill 
Noon,  and  C.  B.  Stiff,  former  district 
manager  for  the  Minnesota  Amusement 
Co.  After  the  induction  of  officers,  Presi- 
dent Noon  presented  Judge  McKinney 
and  yours  truly  with  TMA  life  member- 
ship cards. 


TYPICAL   LONE-STAR   STATE    HOSPITALITY 


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^S£ 

While  attending  the  State  Federation  of  Labor 
convention  in  Beaumont,  Texas,  IA  President 
Walsh  was  presented  with  gold  cuff  links  and 
tie  clasp,  emblematic  of  the  State  of  Texas 
(what  else?)  by  J.  H.  Fehl,  Secretary-Treasurer 
of  Beaumont  Local  183. 

One  of  the  busiest  guys  at  the  meeting 
was  Frank  Galluzzo,  former  Grand  Lodge 
secretary-treasurer.  However,  at  the  close 
of  the  sessions  we  carried  Frank  off  on 
a  sightseeing  tour  which  wound  up  at 
Coney  Island.  We  enjoyed  meeting  many 
friends  of  our  early  days,  among  them 
being  Jim  Perry,  Local  169,  Oakland, 
Calif.,  and  Luke  Callahan,  Cincinnati, 
Local  5. 

Grand  Lodge  officers  elected  for  two 
year  terms,  1949-1951,  are:  president, 
Wm.  R.  Noon  (Lodge  1,  NYC)  ;  1st  vice- 
president,  Wally  Young  (Lodge  1, 
NYC)  ;  2nd  vice-president,  W.  C.  Muel- 
ler (Lodge  4,  Chicago)  ;  3rd  vice-presi- 
dent, James  Perry  (Lodge  26,  Oak- 
land) ;  4th  vice-president,  W.  C.  Rock- 
wood  (Lodge  11,  Toronto);  5th  vice- 
president,  Joseph  McCarthy  (Lodge  1, 
NYC)  ;  6th  vice-president,  Luke  Calla- 
han (Lodge  33,  Cincinnati)  ;  7th  vice- 
president,  Marcus  Rattiner  (Lodge  1, 
NYC)  ;  secretary-treasurer,  Philip  Hit- 
ter (Lodge  67,  Long  Island)  ;  trustees, 
Edward  Schneider  (Lodge  38,  Bronx). 
Ww.  W.  Friedman   (Lodge  67.  Long  Is- 


IA     ELECTIONS 

LOCAL  38,  DETROIT,  MICH. 

E.  Clyde  Adler,  pres.;  C.  Apcar,  1st  vice- 
pres. ;  A.  Finley,  2nd  vice-pres.;  Geo.  Glen- 
wallis,  sec;  S.  L.  Day,  Sr.,  treas. ;  Jerry 
Bric,  bus.  mgr.;  Ed  McMillen,  sgt.-at-arms. 

LOCAL  412,  SARASOTA,  FLA. 

B.  A.  Bonnett,  pres.;  B.  Brollier,  vice- 
pres.;  J.  E.  Sanders,  sec.-treas.;  J.  A.  Scobie, 
bus.  mgr.;  E.  J.  Gallagher,  sgt.-at-arms; 
Scobie  and  Gallagher,  del.  to  Central  Labor 
Union. 

LOCAL  597,  WACO,  TEXAS 

H.  C.  Fuston,  pres.;  E.  F.  Roberts,  vice- 
pres.;  W.  R.  Foster,  rec.-sec;  A.  M.  Pudig, 
fin-sec;  W.  H.  Yopp,  sgt.-at-arms;  E.  F. 
Roberts,  S.  E.  Burdette,  and  J.  G.  Daniels, 
trustees. 


land;  Joe  Schneider  (Lodge  30,  Brook- 
lyn) ;  Paul  Stahl  (Lodge  1,  NYC)  ; 
James  Sullivan  (Lodge  1,  NYC)  ;  Al- 
bert Fried  (Lodge  30,  Brooklyn)  ;  Nat 
Nadel  (Lodge  67,  Long  Island)  ;  chap- 
lain, Thomas  Lloyd  (Lodge  67,  Long 
Island)  ;  laws,  appeals  and  grievance 
committee,  James  Dwyer  (Lodge  1, 
NYC)  ;  Charles  Eichhorn  (Lodge  67, 
Long  Island)  ;  Frank  Galluzzo  (Lodge 
4,  Chicago)  ;  marshall,  James  P.  Pare 
(Lodge  38,  Bronx);  and  tiler,  Georce 
Postel    (Lodge  33,  Cincinnati). 

•  Recent  out-of-town  visitors:  Harry 
Strong,  president  of  the  Strong  Electric 
Corp.,  manufacturers  of  the  famous 
Strong  arc  lamps,  the  Strong  spotlights, 
and  other  projection  equipment,  dove- 
tailed his  41st  wedding  anniversary  with 
a  visit  to  the  offices  of  IP.  In  our  dis- 
cussions about  various  technical  phases 
of  the  industry,  Harry  waxed  most  en- 
thusiastic about  his  new  1950  lamp, 
which,  he  promises,  will  estabbsh  new 
high  standards  of  screen  illumination. 

Accompanied  by  National  Carbon's 
Bill  Kunzmann,  Pete  Mole,  head  of  Mole- 
Richardson  Co.,  West  Coast  manufactur- 
ers of  photographic  lighting  equipment, 
paid  us  a  visit  shortly  after  landing  in 
New  York  from  a  three-months'  tour  of 
Europe.  Pete  enjoyed  his  European  jaunt 
immensely.  Some  of  his  experiences,  as 
he  related  them,  would  constitute  a  pleas- 
ant evening's  entertainment  in  any  com- 
pany. 

Charlie  Hahn,  president  of  J.  E. 
McAuley  Mfg.  Co.,  makers  of  Peerless 
Magnarc  lamps,  also  paid  us  a  visit  and 
had  some  very  interesting  comments  to 
make  on  the  controversial  topic  of  cool- 
ing agents  for  film  equipment.  His  com- 
ments will  be  included  in  a  symposium 
on  this  subject  in  our  next  issue. 

Lawrence  Sherman,  Syracuse  Local 
376;  Russ  Rubin,  Detroit  Local  199;  Joe 
Caplan,  Boston  Local  182,  and  Frank 
Galluzzo.  Chicago  Local  110,  also  stopped 
in  to  say  hello  to  the  IP  staff. 

RCA's  New  Plan  for  Servicing  of 
Drive-In  Speakers,  Boxes 

RCA  Service  Co.  is  now  offering  a 
plan  for  the  servicing  of  drive-in  theatre 
in-car  speakers  and  junction  boxes,  for 
a  nominal  flat  rate  per  week.  The  plan 
includes  parts  replacement,  labor  and 
material  costs,  shipping  containers,  and 
prepaid  transportation  both  ways  on  re- 
paired speakers. 

The  plan  aims  to  free  exhibitors  from 
the  need  for  arranging  for  repairs  and 
the  stocking  of  parts.  Contract  payments 
are  suspended  during  off-season  months. 


Loew's  Profit  Up  Over  '48 

Loew's,  Inc.  in  the  40  weeks  ending 
June  9  last  had  a  net  profit  after  taxes  of 
$5,160,773,  which  is  $431,710  greater 
than  in  the  comparable  period  last  year. 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


17 


Chicago  Theatre-WBKB  Intermediate 
Full-Screen  Tv-Film  System 

WITH  the  intermediate  film-television  system  at  the  Paramount  Thea- 
tre in  New  York  City  shrouded  in  secrecy  (the  regular  theatre  pro- 
jection crew  may  not  enter  the  area  where  the  equipment  is  installed)  IP 
turned  to  Gene  Atkinson,  business  manager  for  Local  110,  for  an  elabora- 
tion of  a  picture  layout  of  the  WBKB  (Tv) -Chicago  Theatre  film-Tv  sys- 
tem which  appeared  in  Television  Forecast* 

Since  Local  110  long  since  rejected  the  absurd  argument  that  only 
"qualified  technicians  with  special  training  and  aptitude"  (meaning  non- 
IA  men,  of  course)  could  handle  Tv  equipment,  Atkinson  was  able  to  com- 
mission two  Local  110  members  to  supply  the  notes  on  which  this  article 
is  based.  These  men,  Bobby  Burns  and  Ira  Jacobsen,  have  proved  over  a 
period  of  many  months  that  members  of  regular  IA  projectionist  Locals 
need  not  give  wav  to  any  other  group  when  it  comes  to  doing  a  fine  job 
on  such  set-ups. 

Moderate  Space  Available  in  Any  Modern  Theatre 

The  Chicago  Theatre  system  is  an  improved  version  of  the  intermediate 
film  equipment  installed  in  the  Paramount  Theatre  in  New  York.  No 
apparatus  is  required  to  be  set  up  in  the  theatre  auditorium,  and  no 
additional  space  is  needed  backstage.  It  seems  safe  to  say  that  any  fairly 
modern  theatre  could  provide  the  necessary  space  for  this  equipment.  At 
the  Chicago  Theatre  a  room  formerly  used  as  a  music  library  was  slightly 
enlarged  and  serves  the  purpose  very  well. 

Basically,  the  Chicago  Theatre  system  comprises  a  Tv  receiver  with 
circuitry  so  arranged  that  either  a  negative  or  a  positive  image  may  be 
made  to  appear  on  the  cathode  ray  tube.    This  image  is  then  photographed 

by  an  Ackley  camera  which  utilizes  an      

electronic  shutter.  This  camera  alone  is 
valued  at  $11,000. 

Synchronous  power  supplies  for  the 
image  recorder  and  the  shutter,  together 
with  the  synchronizing  Tv  generator,  es- 
tabbsh  the  basic  frequency  rates,  and 
no  interlocking  of  the  monitor  and  the 
image  recorder  is  necessary.  The  devel- 
oping machine  is  a  high-speed  device 
capable  of  processing  the  film  in  40  sec- 


Fiqure  4 


*  Published  weekly  at  185  No.  Wabash  Ave.,  Chicago. 


onds!  The  film  travels  through  three 
vertical,  stainless-steel  cabinets  for  de- 
veloping, washing  and  fixing,  respective- 
ly, and  thence  over  a  drying  frame. 
Within  66  seconds  from  the  photograph- 
ing of  the  Tv  image,  the  film  is  projected 
upon  the  theatre  screen  bearing  a  26-foot 
image! 

Any  cathode  ray  tube  produced  by  a 
reputable  Tv  equipment  manufacturer 
for  video  recording  may  be  used.  DuPont 


Figure  5 

or  Eastman  fine-grain  master  positive  film 
may  be  used  for  either  the  negative  or 
positive  recordings. 

Burns  and  Jacobsen  find  that  a  moni- 
toring projector  and  a  screen  directly  in 
line  with  and  following  the  processing 
machine  is  indispensable  for  best  results. 
They  also  favor  the  use  of  a  standard 
soundhead  on  this  projector.  Synchron- 
ous motors,  while  not  used  in  the  Chicago 
Theatre  set-up,  are  recommended  for  this 


18 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


projector  as  well  as  for  the  projector  in 
the  theatre  projection  room. 

A  graphical  exposition  of  the  step-by- 
step  procedure  in  "snatching"  a  Tv 
image  off  the  air,  imprisoning  it  upon 
film  and  projecting  it  onto  the  26-foot 
screen  appears  on  this  page.  Fig.  1  shows 
(upper)  Jacobsen  and  Burns  and  (lower) 
Carl  Maurer  (IA  Lab.  Technicians  Local 
702)  threading  the  recording  camera.  In- 
cidentally, this  camera  was  developed  by 
Maurer. 

Figure  2  shows  the  film  beginning  its 
long  trip  through  the  intermediate  sys- 
tem, moving  out  of  the  camera  into  the 
processor.  Jacobsen  is  shown  threading 
the  tension  takeup  loop  of  the  processing 
unit. 

Film  Dried  Within  10  Seconds! 

Not  a  bicycle  wheel  (Fig.  3)  but  a 
large  drying  cylinder  is  this  device 
through  which  the  wet  film  travels  and 
is  dried  by  jets  of  hot  air  within  10  sec- 
onds. Here  Burns  is  shown  getting  the 
film  into  proper  positioning  for  its  un- 
broken run  to  the  theatre  projection 
room  20  yards  distant  from  the  tele- 
transcription  room.  In  Fig.  4  Jacobsen 
is  shown  at  the  control  panel  (directly 
under  the  drying  unit)  which  regulates 
the  speed  of  the  film  as  it  heads  for  the 
theatre  projection  room. 

Arriving  in  the  projection  room  and 
still  untouched  by  human  hands  is  a 
thoroughly  dry,  high-quality,  35-mm 
print  containing  both  sight  and  sound 
records — the  same  as  a  conventional 
theatre  projection  print.  Note  entry  of 
the  film  into  the  upper  magazine  of  the 
projector  (Fig.  5)  which  is  being 
threaded  by  Art  Devent,  Chicago  Thea- 
tre staff  projectionist  and,  of  course,  a 
member  of  Local  110. 

Variety  of  Program  Pickups 

Providing  that  proper  authorization  is 
forthcoming  from  the  Federal  Communi- 
cations Commission,  the  Chicago  Thea- 
tre and  the  WBKB  staffs  are  prepared 
to  handle  programs  for  theatres  in  any 
one  of  a  variety  of  ways : 

1.  A  telecast  from  WBKB  may  be 
picked  up  by  a  conventional  type  an- 
tenna. 

2.  A  telecast  may  be  "piped"  from 
WBKB  to  the  theatre  recorder  via 
matched  telephone  lines  or  by  microwave 
relay  from  station  roof  to  theatre  roof. 

3.  A  Tv  network's  coaxial  cable  dis- 
tribution system  may  be  fed  to  the  thea- 
tre via  telephone  lines. 

4.  A  sports  event  may  be  picked  up 
privately  by  the  Chicago  Theatre's  own 
mobile  camera  chain  and  flashed  to  the 
screen. 

5.  A  studio  show  may  be  picked  up 
privately  by  the  Chicago  Theatre's  own 
studio  camera  and  then  "piped"  over  a 


The  Origins  of  the  'Magic  Lantern'1 

A  critical  survey  of  old  and  new  literature  reveals  the  development  of  the  modern  slide 
projector  out  of  the  old  "art  of  mirror  writing",  which  in  its  turn  can  be  derived  from  the 
silhouette.  A  wrong  interpretation  of  a  passage  in  an  old  book  which  describes  a  camera 
obscura  caused  the  wrong  opinion  that  the  slide  projector  must  have  developed  therefrom.' 
This  contrivance,  however,  was  the  forerunner  of  the  modern  photographic  camera. 


FIG.    1.     Representation    of    Kircher's    'Magic    Lantern'    (1671). 


By  J.  VOSKUIL 

Research  Chemist,  Geldermalsen,  Holland 

T  IS  usually  held  that  the  slide  pro- 
jector, formerly  called  the  "magic 
lantern"  has  its  origin  in  the  "camera 
obscura,"  and  in  this  connection  the 
names  of  Porta  (1538-1615)  and  of  Ath- 
anasius  Kircher  (1602-1675)  are  mem- 
tioned.  The  latter  was  alleged  to  have 
constructed  the  magic  lantern  in  the 
middle  of  the  17th  century.  He  de- 
scribed it  in  the  second  edition  of  the 
voluminous  and  abundantly  illustrated 
"Ars  Magna  Lucis  et  Umbrae"  ("The 
Great  Art  of  Light  and  Shadow,"  1671) 
accompanying  which  were  two  illustra- 
tions, one  of  which  is  shown  in  Fig.  1. 

Principles  of  the  Camera  Obscura 

A  closer  study  of  the  literature  of  this 
subject,  however,  reveals  another  origin 
of  the  magic  lantern,  which  may  be 
traced  back  to  the  very  old  "silhouette 
show,"  and  in  this  development  the  im- 
portance of  Kircher  and  Porta  is  not  so 
great  as  is  generally  accepted. 


t  J.   Soc.   M.   P.   Eng..    Dec.    1948. 


Before  we  continue  with  the  subject, 
an  explanatory  remark  should  be  made 
on  the  principles  of  the  camera  obscura 
and  the  modern  projector.  The  latter 
forms  by  means  of  a  lens,  the  objective, 
a  real  inverted  image  of  an  object,  which 
therefore  can  be  projected  on  a  screen. 
The  nearer  the  object  (slide,  film)  to  the 
focus  of  the  objective,  the  larger  the 
image  on  the  screen  and  the  larger  the 
distance  between  screen  and  objective. 
Thus  in  slide  and  film  projectors  the 
slide  or  the  film  is  placed  practically  in 
the  focus  of  the  projecting  lens. 

By  moving  the  object  from  the  objec- 
tive, the  image  will  become  smaller  and 
smaller  until  it  stands  practically  in 
focus  when  the  object  is  at  a  great  dis- 
tance from  the  lens.  In  this  way  we  have 
changed  the  projector  into  the  camera 
obscura,  and  therefore  the  essential  dif- 
ference between  the  camera  obscura  and 
the  magic  lantern  lies  in  the  position  of 
the  object  before  the  lens. 

The  Italian  Porta,  who  lived  long  after 
the  invention  of  the  camera  obscura  and 

(Continued  on  page  29) 


closed  circuit  to  the  film  recorder. 
Justifiably  proud  of  their  participation 
in  this  new  form  of  entertainment  trans- 
mission, the  Local  110  fellows  involved 
are  most  articulate  when  discussing  how 
they  successfully  resisted  the  onslaughts 
of  other  crafts,  as  well  as  of  unaffiliated 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


"engineers,"  which  sought  jurisdiction 
over  this  form  of  Tv  work.  "Tv  is  just 
another  type  of  show  business,"  say  the 
Chicago  boys,  "and  there's  no  type  of 
show  business  work  that  we  can't  do  not 
only  just  as  well  but  better  than  any 
other  craft  group." 


19 


CAST 


Final  Decision  Nears  on  the  Future  of  Theatre  Tv 


JULY  marked  an  important  milestone 
in  the  history  of  theatre  Tv  when  the 
Federal  Communications  Commission 
called  upon  20th  Century-Fox  Film  Corp. 
and  Paramount  Television  Productions, 
the  only  licensees  of  experimental  theatre 
Tv  stations,  and  the  Society  of  Motion 
Picture  Engineers  to  submit  comprehen- 
sive data  on  frequency  needs  and  plans 
so  that  the  Commission  can  formulate 
rules  and  standards  for  a  full-fledged  na- 
tion-wide theatre  Tv  service. 

Shortly  after  this  call  by  the  FCC,  the 
Motion  Picture  Association  (Johnston  or- 
ganization), composed  of  top  producing 
and  distributing  companies,  petitioned  the 
FCC  for  public  hearings  looking  toward 
the  allocation  of  channels  for  instituting 
a  national  theatre  Tv  set-up. 

Obviously,  the  motion  picture  industry 
was  on  the  verge  of  emerging  from  its 
self-spun  cocoon  of  indifference  when 
the  call  came  from  the  FCC,  but  the  lat- 
ter's  action  in  asking  for  basic  data  as  to 
the  intent  of  the  film  industry  served  to 
spur  the  heretofore  laggard  film  com- 
panies. 

First  Theatre  Tv  Contract  Set 

Almost  simultaneously  with  the  afore- 
mentioned moves  came  the  announce- 
ment of  the  signing  of  the  first  contract 
for  the  permanent  installation  of  RCA's 
instantaneous  projection  equipment,  pro- 
ducing 15  x  20  foot  Tv  pictures,  in  the 
Fox  Theatre,  Brooklyn,  scene  of  the  re- 
cent showing  of  the  Walcott-Charles  fight 
pictures  via  a  temporary  theatre  Tv  setup. 

Of  special  significance  was  the  inclu- 
sion in  the  FCC  statement  of  a  query 
bearing  on  whether  common  carrier  relay 
facilities  (Bell  System)  can  handle  thea- 
tre Tv  broadcasts  or  if  there  is  a  place 
for  regular  theatre  Tv  video  relay  service. 
This  point  is  known  to  have  been  dis- 
cussed at  length  in  the  various  meetings 
of  exhibitors,  technicians  and  film  com- 
pany representatives. 

Immediately  following  the  FCC  pro- 
nouncement came  word  from  the  SMPE 
that  a  comprehensive  reply  to  all  ques- 
tions posed  would  be  in  the  hands  of  the 
FCC  by  the  Sept.  2  deadline.  Although 
separate  briefs  will  undoubtedly  be  filed 
by  all  three  respondents,  it  is  a  foregone 
conclusion  that  all  segments  of  the  indus- 
try will  get  together  and  agree  in  ad- 
vance as  to  just  what  requests  will   be 


submitted  for  Commission  consideration. 
Installation  of  the  Tv  equipment  in  the 
Fox  Theatre  (4100  seats)  will  be  made 
within  six  months,  it  was  announced. 
Although  similar  in  principle  and  con- 
struction to  the  RCA  experimental  thea- 
tre Tv  projector  used  for  the  fight  pic- 
tures, the  production  model  covered  by 
the  contract  will  employ  a  larger  spheri- 
cal mirror  (28  inches  instead  of  20)  to 
achieve  a  60-foot  projection  throw.  This 
will  permit  mounting  of  the  optical  bar- 
rel directly  on  the  front  of  the  balcony, 
without  an  extension  platform. 

Projectionist  Control  Implied 

RCA  stated  that  "the  control  console 
and  all  amplifiers,  power  supplies,  and 
associated  equipment  will  be  located 
outside  the  theatre  auditorium";  but  IP 
interprets  this  to  mean  that  these  units 
will  be  installed  in  the  projection  room 
via  a  run  of  coaxial  cable  and  will  be 
operated  by  the  regular  theatre  projec- 
tion crew  (see  IP  for  July,  p.  18). 

Chief  concern  of  the  movie  theatre  field 
anent  Tv  was  succinctly  expressed  re- 
cently by  Si  Fabian,  owner  of  the  Fox 
Theatre,  as  follows: 

Programming  Chief  Concern 

"The  whole  thing  is  like  chasing  your 
own  tail  around.  To  meet  the  cost  of 
equipment  (about  $25,000  plus  installa- 
tion) you  have  to  have  some  guarantee  of 
large-screen  programming  that  will  draw. 
On  the  other  hand,  the  manufacturers 
won't  go  ahead  unless  they  first  receive 
a  large  bulk  of  orders.  The  net  result  is 
that  the  exhibitor  is  afraid  to  order  equip- 
ment without  assurances  of  program  sup- 
ply, and  the  manufacturer  is  afraid  to 
make  sets  without  those  orders." 

This  concern  was  pointed  up  by  one 
of  Fabian's  first  moves  after  inking  the 
RCA  contract.  His  appeal  to  National 
Broadcasting  Co.  for  data  on  possible 
program  material  elicited  a  prompt  re- 
Government  Color  Tv  Committee 

The  National  Bureau  of  Standards  has 
organized  a  Color  Tv  Committee  to  sur- 
vey the  present  status  and  future  pros- 
pects of  color  Tv.  The  committee  will 
confine  its  attention  to  the  scientific  and 
technical  phases  of  the  problem,  report- 
ing to  Senator  Johnson  (Col.),  chair- 
man of  the  Senate  Committee  on  Inter- 
state and  Foreign  Commerce. 


sponse  from  Charles  R.  Denny,  web  vice 
president,  that  NBC  would  be  pleased  to 
give  quotations  on  the  production  of 
"specific  programs  to  fit  your  specific 
needs." 

As  to  whether  NBC  will  make  avail- 
able to  theatres  such  network  programs 
as  may  be  requested,  Denny  said  that  this 
angle  would  induce  "some  extremely 
complicated  problems.  In  a  great  num- 
ber of  instances  special  clearances  for 
theatres  would  have  to  be  obtained,  and 
in  many  cases  it  may  be  impossible  or 
impracticable  for  us  to  obtain  them. 

"Nevertheless,"  concluded  the  NBC 
executive,  "we  will  do  what  we  reason- 
ably can  to  obtain  or  assist  you  in  obtain- 
ing appropriate  rights.  .  .  ." 

General  Uncertainty  Prevails 

This  is  small  comfort  to  any  exhibitor 
with  a  $25,000  investment  for  Tv  equip- 
ment, was  the  general  industry  opinion, 
quite  apart  from  the  certainty  that  any 
network  Tv  programs  that  might  be  re- 
leased to  theatres  would  inevitably  con- 
tain every  visual  and  spoken  commercial 
plug  for  a  given  program's  sponsor. 

While  July  was  a  notable  month  in  the 
continuing  struggle  between  home  and 
theatre  Tv,  September  will  see  the  motion 
picture  theatres'  case  pleaded  with  the 
utmost  vigor  before  the  FCC,  and  late 
Fall  likely  will  mark  the  period  when 
the  final  decision  is  rendered  as  to 
whether  the  Fabian  or  any  other  theatre 
will  need  worry  further  about  Tv  equip- 
ment ;  in  fact,  whether  the  motion  picture 
industry  as  a  whole  will  have  to  go  along 
on  its  present  basis  of  straight  film  fare. 

•        •        • 

Zenith  Asks  Phonevision  OK 

Zenith  Radio  has  asked  the  FCC  to 
permit  a  three-month  trial  of  Phonevision. 
About  250  subscribers  in  the  Lakeview 
telephone  exchange  in  the  Chicago  area 
would  receive  a  Zenith  receiver  with  the 
needed  equipment,  and  special  telephone 
lines  would  be  installed. 

How  Phonevision  Works 

Zenith's  Chicago  station,  W9XZV, 
would  be  used  for  the  transmission  of 
frequent  exclusive  programs  which  would 
come  in  scrambled  on  all  sets  not 
equipped  with  Phonevision;  while  sub- 
scribers to  the  system  would  simply  call 
the  telephone  company  and  ask  for  one 
of  the  available  programs.  Thereupon,  a 
special    signal   is   transmitted    from   the 


20 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


telephone  company,  electronically  releas- 
ing a  key  in  the  Phonevision  unit  of  the 
subscriber's  set,  and  the  program  can 
then  be  received.  Any  set  can  be  equipped 
with  the  necessary  Phonevision  unit.  Ze- 
nith said. 

Plan  would  permit  a  subscriber  to  se- 
lect only  those  offerings  in  which  he  is 
interested,  with  monthly  billings  being 
made  on  the  basis  of  programs  for  which 
the  special  un-scrambling  signal  has  been 
given. 

•        •        • 

Another  Inconclusive  Tv  Survey 

Tv  has  little  effect  upon  motion  picture 
attendance  among  those  families  who  have 
owned  their  sets  more  than  a  year,  according" 
to  a  study  completed  recently  by  the  Psy- 
chology Dept.  of  Princeton  University. 
Among  those  who  have  had  their  Tv  re- 
ceivers for  from  one  to  nine  years,  reports 
Television  magazine,  the  average  weekly  at- 
tendance at  motion  picture  theatres  is  0.71. 
Exclusively  radio  set  owners  compile  a 
weekly  average  of  0.81. 

"Taking  the  results  at  their  face  value," 
the  survey  concludes,  "the  indication  is  that 
Tv  has  decreased  motion  picture  attendance 
only  slightly.  A  decrease  of  about  13%  is 
shown  in  the  Tv  sample  as  a  whole,  but  this 
lower  average  is  due,  in  part,  to  the  large 
number  of  'A'  income  homes  in  this  sample! 


The  upper  income  group  goes  to  the  movies 
less  frequently  than  any  other  one." 

Summary  of  Inconclusive  Conclusions 

The  study  was  undertaken  in  an  attempt 
to  determine  Tv's  influence  upon  family 
habits  "after  its  novelty  has  worn  off."  The 
finding  confirmed  the  fact  that  important 
changes  do  take  place  in  home  entertain- 
ment habits,  but  indicate  also  that  "it  is 
unwise  to  jump  to  the  conclusion  that  Tv 
threatens  the  future  of  much  organized  enter- 
tainment." 

Results  showed  that  night-time  radio 
listening  has  fallen  off  sharply,  that  Tv  set 
owners  attend  sporting1  events  more  than  do 
the  owners  of  radio  sets,  that  magazine 
leading  is  higher  among  Tv  owners  and 
that  it  tends  to  knit  the  family  unit  together 
more  closely  when   they  are  at  home. 


Juke  Box  Tv  in  Jersey  Restaurant 

G.  E.  has  installed  an  experimental  juke 
box  Tv  system  in  a  Hoboken,  N.  J.  luncheon- 
ette. "We  want  to  see  if  John  Q.  Public 
will  pay  five  cents  to  see  three  minutes  of 
Tv  served  right  in  his  own  booth  at  a  cafe 
or  restaurant,"  was  the  G.   E.   comment. 

Wall-mounted  sets  in  booths  are  operated 
by  a  "master  control  unit"  which  can  handle 
up  to  20  wall  sets.  Patrons  may  regulate 
volume  of  sound,  but  the  proprietor  selects 
the   programs. 


Contribution  to  Philology 

Dr.  Lee  de  Forest,  of  radio  fame,  in- 
quires of  the  editors  of  Tele-Tech  whether 
they  have  heard  the  appended  definition 
of  a  radio  engineer.  Incidentally,  the 
Dr.,  while  not  claiming  authorship,  states 
that  the  item  "has  a  lot  of  truth  in  it." 

"A  Radio  Engineer  is  a  person  who  passes 
as  an  exacting  expert  on  the  basis  of  being 
able  to  turn  out  with  prolific  fortitude  in- 
finite strings  of  incomprehensible  formulas 
calculated  with  micromatic  precision  from 
vague  assumptions  which  are  based  on  de- 
batable figures  taken  from  inconclusive  ex- 
periments carried  out  with  instruments  of 
problematical  accuracy  by  persons  of  doubt- 
ful reliability  and  questionable  mentality 
for  the  avowed  purpose  of  annoying  and  con- 
founding a  hopelessly  chimerical  group  of 
isoteric  fanatics  referred  to  altogether  too 
frequently  as  'practical  radiomen'." 


Kodak  Processing   Plant  in  Dallas 

Eastman  Kodak  has  started  construction 
on  a  new  wholesale  branch  and  processing 
station  in  Dallas,  Texas.  Intended  to 
lighten  the  burden  on  the  Chicago  office 
which  now  serves  the  Southwest,  this  new 
Kodak  branch  will  process  8-  and  16-mm 
motion  picture  film  in  both  black-and-white 
and  Kodachrome. 


Pulsed-Light  Optical   Unit  for  RCA  TP-35B   Projector 


The  pulsed  light  source  employed  in 
the  RCA  TP-35B  projector  for  Tv  pro- 
vides adequate  light  output  with  negligi- 
ble heating  of  the  film  or  film  gate.  In 
addition,  it  obviates  the  need  for  a  me- 
chanical shutter  mechanism.  The  low 
heating  feature  of  the  pulsed  light  source 
makes  it  possible  to  stop  the  film  and 
project  a  single  frame  as  a  still.    If  this 


were  done  with  conventional  arc  lighting, 
the  extreme  heat  would  destroy  the  film 
in  very  short  order. 

The  pulsed  light  source  is  provided 
from  a  gas-filled  discharge  tube  driven 
by  a  pulsing  power  supply.  The  power 
supply  is  synchronized  with  the  rest  of 
the  system  by  the  studio  sync  generator. 

The  optical  system  is  adjusted  at  the 


FIG.  1.    Simplified  diagram  of  picture  and   sound  optical  systems,  film   path,  and   operation   of 
light  pulse.  See  Fig.  2  for  halftone  representation  of  section  "A". 


factory  so  as  to  require  a  minimum  of 
field  servicing.  The  TP-35B  uses  the 
standard  type  of  optical  system  used  in 
film  projectors.  This  system  consists  of 
a  condenser  lens  system  and  a  projection 
lens  system.  "With  the  G1/^'  focal  length 
lens  as  furnished,  the  proper  projection 
distance  which  gives  the  correct  picture 
size  is  48%"  from  the  film  to  the  mosaic 
of  the  TK-20A  iconoscope.  A  micro- 
meter-type adjustment  is  provided  for 
accurate  setting  of  the  projection  lens 
barrel. 

FIG.  2.    Halftone  representation  of  section  "A" 

in   Fig.  1,  showing  lamphouse  with  pulsed-lighr 

gap  lamp  in  place. 


INTERNATIONAL  PROJECTIONIST 


August  1949 


21 


tl 


R 


To  the  Editor  of  IP: 

Is  the  sound  and  action  so  printed  on 
the  film  that  when  the  "sound"  and  "pic- 
ture" frames  on  the  leaders  are  placed  at 
their  respective  positions  in  the  projector, 
will  the  sound  and  action  at  the  speaker 
mouth  and  screen  be  synchronous?  This 
question  seems  to  me  to  be  a  basic  one 
in  terms  of  precise  projection  practice. 

Assuming  the  answer  to  the  foregoing 
to  be  in  the  affirmative,  I  have  always 
threaded  my  projectors  with  a  loop  about 
three-quarters  of  a  frame  short,  so  that 
the  sound  and  the  picture  would  syn- 
chronize about  35  feet  out  into  the  audi- 
torium. However,  I  wonder  if  I  am  over- 
correcting? 

Arno  Wold 
Opportunity,  Wash. 

[The  Academy  of  M.P.  Arts  &  Sciences 
has  by  exhaustive  tests  determined  the 
proper  distance  between  the  picture  and  the 
sound  on  the  film  so  as  to  strike  a  happy 
average  in  most  theatres. 

Because  sound  travels  so  fast,  it  is  doubt- 
ful if  any  time  lag  would  be  noticeable 
within  a  distance  of  100  feet  from  the  screen 
— that  is,  if  the  projector  be  threaded  in 
accordance  with  Academy  specifications.  Be- 
yond 100  feet  there  is  apt  to  be  a  noticeable 
time  lag,  which,  of  course,  would  be  normal 
if  any  person  were  talking  and  another  listen- 
ing at  this  distance. 

Any  deviation  from  Academy  threading 
recommendation  will  certainly  detract  from 
the  proper  illusion,  irrespective  of  distance 
from  the  screen.  Projectionists  at  large  drive- 
in  theatres  might  have  something  interesting 
to  contribute  on  this  topic. — Ed.] 

To  the  Editor  of  IP: 

We  want  to  express  our  hearty  thanks 
for  the  fine  article  relative  to  rounded 
screen  corners  in  your  May  issue.1  We 
are  using  rounded  screen  corners  now 
and  we  can  say  that  they  encompass 
every  advantage  claimed  for  them  by  Mr. 
Mitchell. 

Lester  A.  Weiss 
Capitol  Theatre,  Kalamazoo,  Mich. 

To  the  Editor  of  IP: 

For  the  edification  of  the  boys,  I 
append  hereto  a  clipping  from  the  tech- 
nical (?)  section  of  a  recent  issue  of  an 
exhibitor  paper: 

Patching  Trucolor  Film 

My  idea  on  patching  Trucolor  film  is  to 
put  strips  of  Scotch  tape  on  both  sides  of 
the  film.  A  patch  made  this  way  is  guaran- 
teed to  hold,  especially  with  safety  film.  I 
find  it. never  fails.— R.  J.  Jones,  Mt.  Holly 
Springs,  Pa. 

I  may  add  that   since  this  item  was 


printed  "bare"  without  editorial  com- 
ment, the  procedure  outlined  is  approved 
by  the  publication  in  question. 

Ray  McAllister 
Los  Angeles,  Calif. 

[The  use  of  Scotch  tape  as  a  splicing  agent 
gives  rise  to  unlimited  possibilities  for  head- 
aches, in  addition  to  inviting  serious  damage 
to  the  projector.  It  requires  no  great  degree 
of  imagination  to  realize  what  would  happen 


should  the  tape  turn  up  an  edge  and  start 
to  roll  back. 

Such  procedure  is  the  worst  possible  pro- 
jection technique,  and  it  is  unfortunate  that 
widespread  publicity  was  given  such  a  stunt 
without  a  word  of  critical  comment. 

Distributed  by  Republic  Pictures  ex- 
changes, Trucolor  stock  (like  Magnacolor, 
Cinecolor,  etc.)  is  what  is  termed  a  dupli- 
tized  film  in  that  it  has  emulsion  on  both 
front  and  back  surfaces.  This  fact  occasions 
a  bit  more  difficulty  in  splicing  than  does 
the  same  chore  on  single-emulsion  safety  or 
nitrate  film. 

On    all    duplitized    stock,   including   Tru- 

(Continued  on  page  26) 


New  Century  Soundfilm  Systems  Reflect  Latest  Advances 


CENTURY  PROJECTOR  CORP.  has 
announced  a  new  line  of  soundfilm 
reproducing  systems,  adaptable  for  every 
situation  from  the  largest  to  the  smallest. 
The  line  is  featured  by  unique  switching 
panels  and  extreme  accessibility  in  get- 
ting at  even  the  smallest  system  unit. 

Figure  1  (left)  shows  a  complete  dual 
channel  system  (40  +  40  —  80-watt)  in- 
cluding main  amplifiers,  power  ampli- 
fiers, exciter  lamp  power,  and  preampli- 
fier power  supply.  In  terms  of  utmost 
flexibility  and  100%  protection  under  any 
and  all  conditions,  this  system  represents 
the  best  available  equipment  in  the  field. 

The  top  group  of  three  panels  (Fig.  1) 
includes  two  main  ampHfiers  (W5-17) 
and  a  switching  panel  (W5-170) .  On  the 
middle  panel  are  two  power  amplifiers 
(W5-16 — 80  watts)  and  a  power  ampli- 
fier switching  panel  (W5-180).  On  the 
bottom  panel  are  two  exciter  lamp  power 
supplies  (W5-15,  d-c)  and  an  exciter 
lamp  power  supply  switching  panel 
(W5-160). 

A  W5-180A  power  amplifier  switching 
panel  may  be  substituted  for  the  W5-180 


FIG.  1   (left). 
FIG.  2  (below). 


1  "Psychological    Elements    in    Projection,"    by    Rob- 
ert  A.    Mitchell;    IP   for   May,    1949,    p.   14. 


Components    of    new    Century    sound    system, 

including  (Fig.  1)  complete  dual  channel  system 

and  (Fig.  2)  the  three  switching  panels. 


panel  when  using  250-500  watt  power 
amphfiers;  and  the  W5-140  exciter  lamp 
power  supply  may  be  used  in  place  of  the 
W5-15  d-c  power  supply. 

Every  projectionist  knows  the  futility 
of  trying  to  trace  a  "floating"  connection 
which  disappears  when  a  cable  or  wire  is 
moved.  In  this  new  Century  design  every 
wire  and  cable  remains  fixed  in  position 
at  all  times,  which  permanency  is  a  real 
advantage.  Anybody  can  easily  trace 
all  Century  circuits,  even  without  a  blue- 
print, and  can  test  every  circuit  for  con- 
tinuity. 

Figure  2  (right)  shows  the  three 
switching  panels  in  a  closer  view.  At 
the  top  is  the  main  amplifier  switching 
panel  (W5-170),  with  two  switch  posi- 
tions. Position  No.  1  connects  the  main 
amplifier  No.  1  into  the  power  circuit, 
together  with  all  power  circuits  to  the 
preamplifiers,  photocells,  etc.  Position 
No.  2  connects  main  amplifier  No.  2  into 
the  circuit. 

A  signal  light  is  above  each  switch 
position — one  green,  the  other  red — 
which  easily  identify  the  amplifier  being 
used.  The  main  amplifier  switching 
oanel  is  also  used  for  the  15-watt  main 
amplifiers  (W3-11). 

In  the  middle  is  the  power  amplifier 
switching  panel  (W5-180),  having  four 
positions  with  signal  lights  to  indicate 
the  combination  being  used.  Position  1 
connects  the  main  amplifiers  directly  to 
the  stage  loudspeakers  or  drive-in  speak- 
ers, thus  cutting  out  the  power  ampli- 
fiers entirely.  In  this  position  both  signal 
lights  are  out. 

Position  2  connects  power  amplifier  1 
into  the  circuit,  whereupon  signal  light  1 
is  "on"  and  shows  green.  Position  3  con- 
nects the  power  amplifier  2  into  the  cir- 
cuit, with  signal  light  2  "on"  and  showing 
red.  Position  4  connects  both  power  am- 
plifiers 1  and  2  into  the  circuit,  with  both 
signals  being  lighted. 

At  the  bottom  is  the  exciter  lamp  sup- 
ply switching  panel,  with  two  switch  posi- 
tions. Position  1  connects  power  supply 
1  to  the  lamps;  and  similarly  with  posi- 
tion 2.  In  each  position  the  correspond- 
ing signal  is  lighted,  indicating  by  green 
and  by  red  which  power  supply  is  being 
used.  As  stated,  either  a-c  or  d-c  exciter 
lamp  power  may  be  thus  controlled. 


22 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


THE  GREAT  ENIGMA:  THE 
STEREOSCOPIC    PERSPECTIVE 

(Continued  from  page  15) 

background,  the  pencil  is  seen  twice  and, 
as  it  were,  in  a  transparent  manner.  In 
normal  vision  we  manage  to  nullify  this 
effect  by  the  simple  expedient  of  ignor- 
ing ft. 

These  facts  anent  the  double-imaging 
of  objects  in  stereoscopic  or  binocular 
vision  are  highly  important  in  terms  of 
applying  the  stereoscopic  perspective  to 
photography,  in  which  case  the  double 
image  would  be  disastrous. 

The  perspective  which  has  all  the  char- 
acteristics of  the  stereoscopic  perspective, 
with  the  exception  of  the  aforementioned 
double  image,  is  that  for  which  the 
writer  has  devised  the  name  "trimen- 
sioHal  perspective." 

Stereoscope  Retards  Progress 

The  writer  feels  that  in  deriving  the 
properties  and  characteristics  of  the 
stereoscopic  perspective,  no  less  than  in 
reducing  it  to  definite  terms,  he  has 
proven  conclusively  that  Helmholtz  was 
completely  right  when  he  postulated  its 
existence.  Had  Helmholtz  lived  to  see 
motion  pictures,  and  particularly  a  film 
produced  by  a  transversely  moving  cam- 
era, his  belief  in  the  existence  of  the 
stereoscopic  perspective  would  have  be- 
come a  certainty. 

The  bald  fact  is  that  the  advent  of  the 
stereoscope,  while  a  brilliant  invention, 
served  only  to  confuse  investigators  and 
thus  barred  the  road  to  further  progress 
and  a  true  insight  into  the  stereoscopic 
perspective.  It  gave  rise  to  the  universally 
accepted  fable  that  there  existed  in  the 
brain  an  enigma  which  could  not  be 
solved  with  the  means  available  to  sci- 
ence, and  which  might  very  well  be  be- 
yond the  powers  of  the  human  mind  to 
comprehend. 

The  solution  to  this  enigma  was  hidden 
in  the  mysterious  convolutions  of  the  cor- 
tica,  which  alone  possessed  the  power  to 
merge  two  visual  images.  This  cortical- 
merged  image,  which  defied  measurement 
and  thus  any  systematic  analysis,  is  held 
by  the  writer  to  have  been  proven  herein 
to  be  completely  accessible  to  the  mind 
and  subject  to  precise  definition. 

There  is  No  Enigma 

Once  scientific  workers  possess  the 
facts  relating  to  binocular  or  stereoscopic 
vision  (namely  the  creation  of  a  specific, 
definable  and  calculable  perspective 
which  obeys  laws  as  rigid  as  those  gov- 
erning the  geometric  perspective) ,  it  be- 
comes a  simple  matter  to  produce  optical 
aggregates  which  will  produce  single 
images  with  all  the  attributes  of  stereo- 
scopic vision.  In  fact,  the  writer  many 
years    ago    constructed    such    apparatus, 


suh;k-s 


"w^i" 


SEALED 

LENS  ELEMENTS 


ONE-PIECE 
'  MOUNT 


ANODIZED 
FINISH 


COATED 
'  OPTICS 


SEte 


w& 


?*, 


?*, 


ARE  THE  LENS  ELEMENTS  COATED? 

Yes,  all  glass-to-air  surfaces  (all  surfaces  except 
the  cemented  ones)  are  coated  with  a  thin  film 
of  hard  magnesium  fluoride  on  Snaplite  Series 
II  and  Super-Snaplite  lenses. 

JUST  WHAT  DOES  THIS  COATING  DO? 

The  coating  decreases  internal  reflections  and 
increases  light  transmission  at  each  surface.  By 
practically  eliminating  stray  light,  it  improves 
contrast,  brings  out  colors  more  fully,  and  in- 
creases the  brightness  of  the  picture. 

HOW    MUCH    BRIGHTER    DOES    THE    XENS    COATING 

MAKE   THE   PICTURE? 

The  coating  increases  light  transmission  about 
4%  per  lens  surface.  Thus  the  Super-Snaplite 
having  8  coated  glass-to-air  surfaces  transmits 
about  30  %  more  light  than  would  a  similar  lens 
with  uncoated  elements. 

WHAT  CAUSES  COATED  LENSES  TO  BECOME  CLOUDY? 
The  magnesium  fluoride  coating  does  not  cause 
cloudiness,  but  might,  because  of  its  purple- 
straw  color,  make  the  cloudiness  more  appar- 
ent. Under  the  same  conditions  uncoated  lenses 
will  also  have  the  deposit 

WHAT  IS  THE  DEPOSIT  THAT  FORMS  ON  LENS 

SURFACES? 

This  deposit  may  be  dust,  fumes  from 
lamp  housing  or  oil.  Poor  ventilation 
of  the  projector  or  projection  room 
will  probably  cause  a  deposit  to  form 
on  any  glass  surface  in  the  projector  or 
projection  room. 


"You  Get  the  Most  Uniform  Light  with  Super-Snaplite" 


{^/ofaal  CORPORATION 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


INTERNATIONAL  PROJECTIONIST 


August  1949 


23 


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Produces  a  steady,  sharp,  uniformly 
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Silvered  glass  reflector  and  two- 
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system. 

Draws  only  10  amperes  from  any 
110-volt  A.C.  convenience  outlet. 
Adjustable,  self- regulating  trans- 
former, an  integral  part  of  the  base, 
makes  the  use  of  heavy  rotating 
equipment  unnecessary. 


Easily  operated.  Automatic  arc 
control  maintains  constant  arc  gap, 
free  from  hiss  or  flicker.  A  trim 
of  carbons  burns  one  hour  and  20 
minutes  at  21  volts  and  45  amperes. 

Horizontal  masking  control.  Can 
be  angled  at  45  degrees  in  each 
direction.  Color  boomerang  con- 
tains six  slides  and  ultraviolet  filter 
holder. 

Mounted  on  casters.  Easily  dis- 
assembled for  shipping. 


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which  gave  promise  of  achieving  the 
desired  results. 

Whenever  such  an  aggregate  was 
handed  to  ah  optical  calculator,  the  de- 
sired effects  promptly  disappeared.  The 
aggregate  became  capable  of  producing 
the  undistorted,  geometric  perspective, 
because  the  calculator  knew  that  only 
this  "perfect"  perspective  must  be  the 
aim  of  his  work. 

In  the  motion  picture  field,  several  at- 
tempts have  been  made  to  produce  stereo- 
scopic effects  by  means  of  distortions  ap- 
plied to  the  individual  pictures,  either 
during  the  taking  or  in  the  projection 
process.  Considering  the  data  contained 
in  this  article,  it  is  obvious  that  no 
amount  of  distortion  in  a  geometrically 
correct  picture  will  ever  produce  the 
stereoscopic  perspective. 

Several  attempts  have  been  made  to 
project  real  images  standing  in  the  air 
in  front  of  concave  mirror  arrangements, 
notably  by  Dr.  Kogel  in  Germany,  who 
used  a  mosaic  of  concave  mirrors  with 
quite  some  success. 

Sfereo  Merging-in-Time 

It  is  pertinent  to  mention  the  attempts 
to  create  stereo  effects  by  means  of  pro- 
jecting alternating  stereo  pairs.  High 
hopes  were  held  for  this  process  because 
of  the  striking  stereo  effects  experienced 
when  viewing  a  film  made  by  a  trans- 
versely-moving camera.  Helmholtz  would 
have  immediately  recognized  the  true  sig- 
nificance of  this  phenomena. 

Such  films  serve  to  discredit  the  erron- 
eous concept  that  spatial  vision  may  be 
attained  only  if  each  eye  sees  only  its 
proper  image,  and  that  two  paraxially 
different  images  must  be  seen  separately 
by  two  eyes  in  order  to  be  merged  in  the 
brain. 

These  films  consist  of  a  series  of  pic- 
tures each  one  of  which,  together  with 
the  previous  or  the  following  one,  forms 
a  stereo  pair.  When  projected,  these 
images  are  seen  in  succession.  Often  the 
effect  is  startlingly  real  and  truly  stereo- 
scopic, as  one  observes  depth  and  solid- 
ity and  looks  at  space  rather  than  a  flat 
screen.  Yet,  this  succession  of  stereo  pic- 
tures, as  such  films  really  are,  is  always 
seen  simultaneously  with  both  eyes  (or 
by  one-eyed  people  with  a  single  eye)  so 
that  the  mysterious  merging  power  of 
the  brain  seems  to  work  for  images  in 
succession  just  as  well  as  for  separate 
stereo  images  seen  with  different  eyes. 

How  Images  Merge  in  Time 

The  reason  for  this  merging  process 
in  time  lies,  of  course,  in  persistence  of 
vision  whereby  we  see  the  image  whicli 
just  left  the  screen  and  the  one  being 
projected.  As  both  foveas  are  always  di- 
rected at  the  same  center  of  momentary 
interest,  complete  merging  of  the  parts  of 
the  picture  adjacent  to  such  centers  of 
interest    becomes    quite   easy,    again    be- 


24 


INTERNATIONAL  PROJECTIONIST 


August  1949 


cause  these  are  seen  only  with  great  hazi- 
ness anyway,  so  that  no  greater  confusion 
need  be  felt  if  two  separate  pictures  are 
mixed  around  the  center  of  interest. 

If,  now,  alternate  pictures  taken  from 
the  right  and  left  are  projected,  the 
stereo  sensation  arises  in  the  same  man- 
ner but  is  accompanied  by  a  rapidly 
rising  feeling  of  fatigue,  because  the 
eyes  are  compelled  to  center  the  two 
foveas  on  an  oscillating  center  of  inter- 
est. This  represents  a  definite  hardship, 
of  course,  and  moreover  creates  the  im- 
pression of  excessive  flicker. 

New  Photographic  Aggregates 

Photographic  aggregates,  as  stated 
previously,  can  be  made  which  produce 
single  images  with  all  the  attributes  of 
stereoscopic  vision  and  which  the  writer 
termed  "trimensional  images."  Pictures 
made  with  such  an  aggregate,  whether 
seen  with  both  eyes  or  a  single  eye,  con- 
vey an  impression  of  depth,  solidity  and 
space. 

Pictures  made  with  trimensional  aggre- 
gates may  be  printed  on  ordinary  paper 
or  projected  with  conventional  projec- 
tion apparatus.  No  special  films,  screens, 
analyzers  nor  any  special  viewing  de- 
vices or  separators  are  required  for  view- 
ing, whether  by  one-eye  or  two-eyed 
people. 

Repeatedly  the  opinion  has  been  voiced 
that  if  we  possessed  four  eyes  positioned, 
for  instance,  in  a  diamond  shape,  we 
would  be  able  to  see  stereoscopically  "all 
around"  and  the  result  would  be  a  more 
acute  perception  of  depth.  This  point  is 
important,  because  the  optical  trade 
would  be  able  to  make  aggregates  with 
this  "quadrocular"  perspective  just  as 
easily  and  certainly  with  greater  accur- 
acy than  they  could  make  aggregates 
with  the  binocular  perspective. 

We  know  it  to  be  a  fact  that  if  we  hold 
our  head  sideways,  we  perceive  stereo- 
scopy  in  the '  vertical  sense.  Nature  ig- 
nored the  opportunity  to  endow  us  with 
this,  possibly  superior,  stereo  vision,  thus 
we  must  live  our  lives  out  as  binocular 
bipeds.  It  is  doubtful  whether  the  easily 
attained  quadrocular  perspective  would 
be  any  real  improvement. 

Quadrocular  Perspective? 

The  perception  of  depth,  solidity  and 
space,  the  writer  opines,  is  an  acquired, 
experiential  faculty.  One-eyed  people  de- 
velop this  faculty  in  a  different  manner, 
but  it  remains  an  acquired  faculty.  We 
are  a  binocular  people,  by  a  wide  ma- 
jority, and  that's  that. 

Analysis  of  the  perspective  we  per- 
ceive shows  that  horizontally  we  see  ob- 
jects narrowed  down  and  interspaces 
widened.  Further,  we  noted  that  ratios  of 
width  to  height  change  with  distance,  and 


this  change  is  part  of  the  fund  of  experi- 
ence utilized  in  our  acquired  perceptions 
of  depth  and  distance.  The  writer  feels 
that  this  measuring  rod,  subconsciously 
applied,  must  be  an  important  part  of  our 
mental  visual  armamentum. 

This  interpretation  of  changing  ratios 
between  width  and  height,  however, 
would  be  totally  lacking  in  the  quadro- 
cular perspective,  as  can  be  easily  proven 
by  an  analysis  similar  to  that  applied  to 
the  binocular  or  trimensional  perspective. 

At  best,  it's  a  moot  question  just  wh  < 
kind  of  perspective  should  be  adopted 
for  photographic  purposes,  with  the  final 
judgment  doubtless  reposing  with  the 
general  public  after  having  viewed  one 
or  the  other  kind  of  perspective. 

The  Perspective  of  Tomorrow 

Trimensional  pictures,  the  writer  is 
certain,  will  replace  the  present  geo- 
metric pictures  as  a  matter  of  course. 
The  trimensional  perspective  will  lend  a 
touch  of  amazing  reality  to  photographs 
and  reproductions  of  any  and  all  kinds 
whatsoever.  The  effects  will  be  retained 
in  the  halftone  process,  will  be  universal- 
ly used  in  illustrated  magazines,  and  add 
immeasurably  to  the  enjoyment  of  all 
pictorial  work. 

In  motion  pictures  the  trimensional 
perspective    will    add    the    final    needed 


touch  of  reality,  particularly  if  a  good 
color  process  is  employed  in  making  the 
films.  As  this  perspective  depends  only 
on  the  optical  characteristics  of  the  ag- 
gregate used  as  a  camera  objective,  there 
would  need  be  no  difference  in  treatment 
as  between  black-and-white  and  colored 
film. 

Geometric  Perspective  Inadequate 

There  is  even  a  chance  that  artists  may 
familiarize  themselves  with  the  laws  of 
trimensional  perspective,  and  that  these 
laws  will  be  taught  in  the  art  schools 
which  now  concentrate  on  teaching  the 
laws  of  geometric  perspective. 

While  recognizing  the  importance  in 
an  historical  sense  of  the  geometric  per- 
spective, the  writer  hopes  fervently  that 
it  will  be  abandoned,  because  while  it  is 
"undistorted"  it  certainly  is  totally  in- 
adequate in  our  age  of  great  scientific 
development. 


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PROTECTING  THE  THEATRE— FIRST  PLACE  IN  ENTERTAINMENT 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


25 


LETTERS  TO  THE  EDITOR 

(Continued  from  page  22) 

color,  the  emulsion  on  both  surfaces  must 
be  scraped,  and  the  removal  of  the  sub-base 
is  a  bit  more  critical  than  on  other  safety 
film  or  on  nitrate  stock.  Explicit  step-by-step 
instructions  for  the  splicing  of  duplitized 
stock  has  been  given  in  these  columns  on 
several  occasions  recently,  notably  in  the 
first  inclusive  article  anent  safety  film  ever 
published  in  the  industry  press.1    The  splic- 


1  "Safety    Film:    Projection    Factors,"    by    Henry    B. 
Sellwood;    IP   for   Nov.    1948,   p.   9. 


on 


9 


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HIGH 


QUAUTy 


F»l*  Mar     A'9°"6« 


Precision  designed,  ruggedly 
constructed,  factory  "aged" 
and  thoroughly  tested  f  ot 

SMOOTH    OPERATION 

CONSTANT    POWER    SUPPLY 

LONG   LIFE 

Guaranteed  for  1,200  op- 
erating hours  when  used 
at    their     proper     rating. 


See  our  exhibit  at  the 
TESMA  Trade  Show, 
Sept.  26-28,  Stevens 
Hotel,  Chicago,   Illinois. 


ASK   YOUR    DEALER 
— HE   KNOWS 


GORDOS   CORPORATION 

86   SHIPMAN   STREET      •      NEWARK  2,  N.  J. 


ing  of  not  only  Trucolor  but  of  all  types 
of  film  should  offer  not  one  whit  of  trouble 
to  the  experienced  projectionist  who  follows 
the  procedure  outlined  in  the  aforemen- 
tioned article. 

Oddly  enough,  for  several  years  prior  to 
1948  Trucolor  had  virtually  a  corner  on  the 
available  supply  of  acetate  film  (not  to  men- 
tion the  various  releases  on  safety  stock  by 
the  Government  during  the  war)  and  pro- 
jectionists accomplished  the  splicing  opera- 
tion in  routine  fashion. 

Unfortunate  it  is  that  circulation  is  given 
such  nonsense  by  exhibitor  papers,  but  since 
neither  the  contributors  of  such  stuff  nor 
the  exhibitors  who  may  read  it  apparently 
know  from  nothing  about  the  projection 
process — and  probably  care  less — the  dam- 
age done  is  probably  minuscule. — Ed.] 

To  the  Editor  of  IP: 

The  table  of  conversion  factors  for 
both  illumination  and  brightness  units 
appearing  in  the  June  1949  issue  of  IP* 
has  been  very  worthwhile,  and  I  am  sure 
that  those  of  us  who  delve  into  the  for- 
eign technical  publications  and  thus  en- 
counter some  of  the  European  units  will 
find  it  most  helpful. 

There  is,  however,  one  error  in  the 
"Brightness"  table.  The  third  line  in  this 
heading  should  read: 

"1   apostilb    (German  Hefner)  = 
0.09  millilambert" 

instead  of  0.9,  as  you  present  it.  There  is 
only  a  slight  difference  between  the  inter- 
national apostilb  and  the  German  ver- 
sion; whereas  the  figures  in  the  table 
published  in  IP  make  it  appear  that  there 
is  a  9-to-l  ratio. 

This  error  was  also  brought  to  my 
attention  by  one  of  the  lighting  techni- 
cians of  the  Bureau  of  Standards. 

Ralph  E.  Farnum 

Engineering  Div.,  General  Electric  Co. 
Nela  Park,  Cleveland,  Ohio. 

[Being  apprised  of  the  source  of  the  data 

*  "  'Stilly  and  Other  Irritants  Reduced  to  American- 
ese,"  p.   12. 


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STAR  CORE,  exclusive  feature  with  the 
Lorraine  Carbons  —  a  manufacturing 
process  that  increases  the  performance 
of  the  carbons. 

A  more  brilliant,  steadier,  more  con- 
sistent white  light — more  economically 
. . .  proven  facts  as  shown  by  tests 
made  under  actually  operating  con- 
ditions. 


Lorraine  Carbons  ore  world  renowned  .  .  . 
the  loraeil  Iheotrei  in  Ihe  U.  S.  one 
throughout  the  world  UJe  Lorraine  Carbons 


WHITE    FOH    DISTRIBUTION   DATA 

CARBONS,  INC. 

BOONTON,  N.J. 

NEW  YORK:  234  WEST  44th  STREET 


which  appeared  in  IP,  Mr.  Farnham,  an  old 
friend  and  co-worker  in  the  projection  vine- 
yard, weighed-in  with  the  appended  enlight- 
ening commentary. — Ed] 

The  fact  that  you  took  the  conversion 
factors  for  lighting  units  from  the  Illu- 
minating Engineering  Society  Lighting 
Handbookf  certainly  absolves  you  from 
blame,  but  it  does  reveal  the  very  inter- 
esting fact  that  the  Handbook  is  wrong. 
On  page  38  of  the  latest  edition  of  Illu- 
minating Engineering  Nomenclature  and 
Photometric  Standards,  which  has  the  ap- 
proval of  the  American  Standards  Asso- 
ciation (ASA  Z7.1-1942)  you  will  note 
that  the  figure  of  0.09  millilambert  equals 
1  apostilb  in  German  units. 

Too  Close  to  the  Forest  .  .  .' 

Your  use  of  the  I.E.S.  Handbook  for 
the  conversion  table  in  IP  for  June  is  a 
good  joke  on  me,  incidentally,  because 
although  /  was  responsible  for  writing 
Section  14  of  the  Handbook,  I  didn't  rea- 
lize that  the  material  you  cited  was  in 
the  book. 

I  am  glad  that  this  pleasant  exchange 
of  correspondence  proves  that  we  and 
many  other  lighting  engineers  do  read 
IP,  and  closely  too. 

Ralph  E.  Farnum 

To  the  Editor  of  IP: 

Why  must  M-G-M  perforate  their  ini- 
tials on  all  splices  that  are  made  in  their 
exchanges?  When  the  film  is  cupped  to 
check  whether  the  splice  is  tight,  it  will 
almost  always  break  at  the  perforations. 

In  the  case  of  the  sample  enclosed  here 
three  frames  were  lost  in  order  to  make 
a  new  splice.    Quite  a  few  exchanges  do 


t  1947    Edition,    Appendix    A-35,    Table    A-17: 
ersion   Factors   for   Lighting  Units." 


"Con- 


WITH  ANY 


LAMP 


IN  ANY  SIZE     THEATRE 


vS;;ii:M;5iii: 


GEORGE  K.  DIAMOS— President, 
Tri-Delta  Amusement  Co.,  Tucson, 
Arizona  (Phoenix  Theatre,  Phoenix 
and  Plaza  Theatre,  Tucson) — says: 

"We  have  been  using  RCA 
Service  for  twenty  years  and 
have  found  it  satisfactory  in 
every  respect." 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


26 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


not  remove  the  film  binder  when  making 
splices. 

Roy  L.  Shenk 
Meyerstown,  Penna. 

[Replying  to  the  foregoing,  M.  D.  O'Brien, 
assistant  director  of  projection  and  sound 
for  Loew's  Theatres,  offers  the  following 

"I  have  examined  the  Metro  splice  sub- 
mitted. It  has  been  the  custom  of  Metro  for 
many  years'  to  use  an  embossing  stamp  on 
all  splices  made  in  their  exchanges.  This 
stamp  does  not  perforate  the  film  and  it 
cannot  be  seen  on  the  screen. 

"The  deficiency  of  the  sample  splice  obvi- 
ously is  not  occasioned  by  the  embossing 
stamp  but  by  an  inferior  patch  caused  by 
poor  cement  or,  in  this  case,  possibly  by  the 


fact  that  the  film  had  been  on  an  extended 
run  and  the  splice  had  dried  out. 

"The  practice  of  embossing  splices  has 
met  with  a  great  deal  of  favor  because  it 
serves  as  conclusive  proof  that  the  exchange 
has  properly  examined  the  print,  an  import- 
ant  assurance   to   the   projectionist."] 

To  the  Editor  of  IP: 

My  own  working  experience  in  all 
kinds  of  projection  rooms  and  with  all 
kinds  of  equipment — good,  bad  and  in- 
different— convinces  me  that  the  advice 
given  in  your  article  "Safety  Film:  Pro- 
jection Factors"1  is  absolutely  sound  and 
trustworthy    in    all    particulars.      I    am 

1  IP    for   November    1948,    p.    9. 


UNBREAKABLE 

Non-Pitting 


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Manvfpctwed  by 

HEYER-SHULTZ,  INC 
CEDAR  GROVE,  N.  J. 


Distributed  Exclusively  by 

NAT  I 


ATJONAt 


happy  to  see  that  the  article  still  is  being 
referred  to,  even  if  by  miffed  splicer 
manufacturers.2 

I  have  used  Griswold  splicers  both 
new  and  considerably  used.  In  fact, 
some  of  them  have  been  so  worn  that  I 
have  had  to  resort  to  hand  splicing  to 
avoid  film  breaks.  Frequently  I  have 
found  it  necessary  to  dismantle  the  splic- 
ers, have  the  parts  re-machined,  and  put 
them  together  again,  making  all  adjust- 
ments more  or  less  by  trial  and  error  in 
order  to  restore  them  to  serviceable  con- 
dition. The  best  of  film  cements  are 
worthless  in  the  face  of  crudely  designed 
splicing  machines. 

I  have  also  found  that  the  shear  bar  of 
the  Griswold  splicer  quickly  becomes 
rounded  at  the  edges  through  daily  use, 
resulting  in  splices  which  are  weakest  at 
their  most  critical  points — the  edges  of 
the  stubs.  The  "doctoring"  of  splices 
made  on  used  Griswold  splicers  by 
brushing  in  a  little  extra  cement  at  the 
edges  and  ends  of  each  splice  and  press- 
ing the  ends  of  the  splice  with  my  fingers 
has  now  become  almost  habitual. 

Perhaps  it  is  a  good  thing  that  the 
vaunted  Griswold  guarantee  does  not  ex- 
tend beyond  one  year. 

Projectionist  Competency  Defended 

It  is  strange  that  Griswold  should  con- 
sider projectionists  incompetent  to  make 
adjustments  on  their  simple  splicing  de- 
vice. Most  projectionists  are  capable  of 
servicing  projectors,  machines  consider- 
ably more  complicated  than  splicers. 

The  pressure  spring,  or  clamp,  is  an- 
other weak  feature  of  the  Griswold,  and 
one  that  requires  adjustment  from  time 
to  time.  This  might  not  be  necessary  if 
a  flat  pressure  bar  of  considerable  width 
were  substituted  for  it.  Furthermore,  the 
pressure  is  not  nearly  great  enough.  Let 
Griswold  improve  their  product  or  else 
furnish  projectionists  with  aligning  tools 
and  instructions  for  making  the  needed 
adjustments. 

What  we  really  need  is  a  new  and 
completely  automatic  splicing  machine, 
even  to  the  application  of  the  film  ce- 
ment. Scraping  should  be  accomplished 
by  a  motorized  grinding,  or  abrading,  de- 
vice. Scraping  on  the  Griswold  is  a  head- 
ache. Personally,  I  have  my  own  scraper 
— an  old  pair  of  scissors  I  have  filed  off 
for  this  purpose.  Sounds  crude?  Well, 
Griswold's  scraper  isn't  good  enough  for 
me;  and  my  old  pair  of  scissors  has 
managed  to  see  me  through  a  decade 
without  a  single  film  break. 

Robert  A.  Mitchell 

2  "Letters    to    the    Editor";    IP   for   June    1949,    p.    17. 


What  is  a  Projector?    ASA  Version 

A  Projector  is  a  device  which  concen- 
trates luminous  flux  within  a  small  angle 
from  a  single  axis.* 

*  Definition  adopted  by  American  Standards  Associa- 
tion.  February  27,  1942. 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


27 


Joint  TESMA-TEDPA  Convention 
at  Chicago,  Sept.  26 

"It's  later  than  you  think,"  warns  Roy 
Boomer,  in  issuing  a  final  appeal  to  all 
interested  parties  to  complete  arrange- 
ments for  participation  in  the  forthcom- 
ing TESMA-TEDPA  (manufacturers  and 
dealers)  convention  to  be  held  at  the 
Stevens  Hotel,  Chicago,  beginning  Sep- 
tember 26.  Although  there  are  very  few 
exhibition  booths  left  for  this  meeting, 
Boomer  advises  that  extraordinary  effort 


ROY  BOOMER 

Executive  secre- 
tary of  manu- 
facturers' asso- 
ciation urges 
prompt  action  on 
TESMA-TEDPA 
convention  ar- 
rangements. 


will  be  made  to  accommodate  every 
manufacturer  who  wishes  to  show  his 
wares.  Also,  hotel  room  reservations 
should  be  made  immediately. 

A  feature  of  the  convention  will  be 
an  open  forum  at  which  will  be  dis- 
cussed the  probable  impact  of  television 
upon  the  motion  picture  theatre,  with 
comment  solicited  from  those  reflecting 
every  shade  of  opinion.  Attendance  at 
this  session  is  expected  to  exceed  2500. 
Both  TESMA  and  TEDPA  will  elect  offi- 
cers and  board  members  at  this  meeting. 


result  in  the  reimposition  of  restrictions 
on  the  importation  of  movie  equipment 
into  Canada. 

Similar  restrictions  imposed  by  Can- 
ada in  1947  have  been  gradually  eased 
since  last  December,  but  exporters  ex- 
pect the  worst  when  Parliament  convenes 
in  September. 


First  Audio  Fair  in  N.  Y.  Oct.  27-29 

The  nation's  first  Audio  Fair  is  to  be 
sponsored  by  the  Audio  Engineering  So- 
ciety at  the  Hotel  New  Yorker,  N.  Y. 
City,  Oct.  27-29  inclusive.  Rooms  and 
suites  comprising  the  entire  sixth  floor 
of  the  hotel  have  been  reserved  for  ex- 
hibitors. 

The  exhibits  and  the  technical  sessions 
to  be  held  each  day  of  the  meeting  will 
cover  recording  and  reproduction  on 
tape,  disc  and  film,  in  addition  to  micro- 
phones, loudspeakers  and  amplifying 
equipment.  No  fee  will  be  charged  any- 
one attending  the  exhibits. 


New  Canadian  Equipment  Ban  Seen 

American  equipment  manufacturers 
and  distributors  are  fearful  that  the  in- 
tensified austerity  program  recently 
charted  by  the  British  government  for 
the  next  two  years  at  least,  in  which  the 
dominions    have    promised    support,    will 


Hundreds  of  Useful  Facts 

on  booth  equioment  will  be  found  in 

THE  SOUND  TRACK 

BOOK  OF  THE  THEATRE 

Price  $10.00 

THE  SOUND  TRACK 
1001  W.  Washington  Blvd.      Chicago  7, 


G.  P.  E.  Tops  '48  Sales,  Earnings 

Consolidated  net  income  of  General 
Precision  Equipment  Corp.  and  subsid- 
iary companies  for  the  three  months  end- 
ed June  30  was  $317,756,  equal  to  53 
cents  per  share  on  the  outstanding  com- 
mon stock.  This  compares  with  consoli- 
dated net  income  of  $297,952  for  the 
same  period  in  1948,  or  50  cents  per  com- 
mon share. 

Net  sales  for  the  second  quarter  of 
1949  totaled  $7,505,491  compared  with 
$6,721,103  for  the  similar  period  of  1948. 


sary  to  use  so-called  "mechanical"  bases,  is 
announced  by  Westinghouse  (Bloomfield, 
N.J.) .  In  some  types  of  lamps,  replacement 
of  the  mechanical  base  with  a  conventional 
base  in  combination  with  the  new  cement 
definitely  improves  the  construction  of  the 
lamp   anent   better   overall   performance. 

Exhaustive  tests  of  the  cement  show  that 
it  will  not  deteriorate  when  subjected  to 
temperatures  as  high  as  446  °F.  This  new 
development  is  an  important  contribution  to 
the  art,  especially  when  operating  lamps  in 
smaller  equipments  and  at  ever-increasing 
temperatures. 


Biggest  Film  Producer  in  the  World? 

Who  is  the  biggest  producer  of  motion 
pictures  in  terms  of  footage  in  the  world? 
The  U.  S.  Army  Signal  Corps  Photo- 
graphic Center  at  Long  Island  City,  N.Y., 
which  now  tops  the  production  of  any 
Hollywood  studio  with  more  than  4  mil- 
lion feet  of  film  a  month — 1%  million 
feet  of  55-mm  negative  and  2%  million 
feet  of  prints. 

A  recent  typical  week  saw  the  Center 
with  233  productions  in  work:  60  script- 
ing, 55  in  work,  and  the  remainder  in 
scenario  or  finished  print  form  awaiting 
clearance. 


New  Inkie  Lamp-Basing  Cement 

The  development  of  a  new  lamp-basing 
cement  for  use  with  lamps  operated  at  high 
temperatures,  where  previously  it  was  neces- 


HUGH  FLANNERY— City  Mana- 
ger, Ashley  Theatres,  Madison,  Wis- 
consin— says: 
"Our  Orpheum,  Parkway,  Strand, 
and  Madison  Theatres  have  been 
regularly  serviced  by  RCA  for 
the  past  fifteen  years.  Complete 
satisfaction  has  been  enjoyed  by 
both  the  management  and  our 
patrons." 
To  get  the  benefits  of  RCA  Service- 
write:   RCA   SERVICE    COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


nuinRP  uimnjER 

Flutter  Suppressor  Wins 
ACADEMY   AWARD! 


The  Academy  of  Motion  Picture  Arts  &  Sciences  recog- 
nized the  value  of  this  development  in  making  its  1947 
award  to  C.  C.  Davis  of  the  Western  Electric  Co. 

CENTURY  can  give  you  this  outstanding  improvement 
in  sound  reproduction   NOW. 


The  Award- 
winning  Hydro 
Flutter  Suppressor 
as  used  in  the 
new  Century 
sound  reproducer. 


Improve  the 
ance    quality   in   your   theatre  —  see 
'  your  dealer  or  write  for  information. 

CENTURY  PROJECTOR  CORP 


New  York,  N.  Y. 


I  '— 


Century  Sound  Reproducer 

■     '-■.•••.   : ■;■■    '.H 


28 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


PERSONAL     NOTES 

Bert  Sanford,  for  the  past  20  years  sales 
manager  for  Altec  Service  Corp.,  has  been 
named  sales  director  for  the  ABC  Vending 
Corp.,  which  has  extensive  theatre  franchises 
for  candy  and  refreshments. 

Sanford,  an  industry  veteran,  began  his 
career  as  an  actor  for  D.  W.  Griffith,  and 
later  entered  the  exchange  field.  He  joined 
ERPI,  predecessor  of  Altec,  in  1929  and  has 
been  active  in  the  sound  equipment  and 
service  field  since  that  time.  He  will  con- 
tinue to  serve  Altec  in  an  advisory  capacity. 

Marty  Wolf  has  been  named  to  the 
Altec  sales  post  vacated  by  Sanford. 

Charles  M.  Odorizzi  has  been  appointed 
vice-president  in  charge  of  servicing  opera- 
tions of  the  Victor  Division  of  RCA.  He  was 
formerly  general  manager  of  the  Mail  Order 
Division  of  Montgomery  Ward  &  Co. 

Dr.  Loyd  A.  Jones,  of  Kodak  Research 
Labs,  has  been  elected  an  honorary  fellow 
of  the  British  Photographic  Society.  This 
election,    considered    a   signal   honor,   is   the 


third  recognition  of  Dr.  Jones  this  year  by 
the  Society:  in  February  he  was  awarded 
the  1948  Progress  Medal,  and  in  May  he 
lectured  before  the  Society  and  won  the 
Hurter  and  Driffield  Medal. 


New  Self-Operative  Soldering   Iron 

Requiring  no  electric  current  or  external 
heat  of  any  kind,  a  new  type  of  soldering 
iron  utilizes  a  chemical  cartridge  that  heats 
the  iron  to  working  temperature  in  5  seconds 
and  maintains  heat  for  6  to  8  minutes, 
depending  on  the  type  of  work  done.  The 
cartridge,  which  is  about  the  size  of  a  small 
flashlight  battery,  contains  a  primer  and  is 
ignited  in  a  manner  similar  to  that  of  firing 
a  bullet. 

After  the  cartridge  has  been  placed  in  the 
copper  tip  of  the  iron,  it  is  set  off  by  the 
impact  of  a  spring  rod  which  is  pulled  out 
and  released  at  the  back  of  the  handle.  The 
pointed  end  of  the  rod  strikes  the  primer 
that  generates  the  heating  action,  which  is 
created  by  the  chemical  mixture  of  metal 
powders  similar  to  magnesium  and  an  oxidiz- 
ing agent. 

The  heat  developed  is  about  250  watts 
peak,  hence  the  iron  can  be  used  on  heavy 
as  well  as  light  soldering  jobs.  A  new 
cartridge  is  required  each  time  the  iron  is 
used.    By  the  Kemode  Mfg.  Co.,  N.  Y. 


ORIGINS  OF  'MAGIC  LANTERN' 

(Continued  from  page  19) 

thus  is  not  the  inventor  as  is  often  sup- 
posed, deserves,  however,  the  merit  of 
having  popularized  it  in  his  famous  book 
"Magica  Naturalis"  (first  edition  1558, 
second  edition  1589  in  Naples),  a  curi- 
ous mixture  of  science  and  charlatanry. 
The  result  was  a  wide  application  of  the 
camera  obscura,  which  in  those  days  in- 
deed had  the  dimensions  of  a  "camera" 
(room,  see  Fig.  2)  as  a  contrivance  for 
performances  of  various  character. 

Porta's  Contrivance  for  'Pictures' 

In  one  of  the  walls  a  simple  spectacle 
lens  was  placed  and  a  hollow  mirror  was 
used  to  reflect  the  images  of  the  objects 
outside  the  room  in  this  lens:  the  pic- 
tures were  thus  projected  on  the  screen, 


the  opposite  wall,  right  side  up.  As  in 
the  modern  theatre,  the  spectators  sat 
facing  this  screen  with  their  backs  to  the 
lens,  which  was  more  or  less  hidden, 
making  the  performance  a  rather  myste- 
rious affair. 

On  an  open  space  in  full  sunlight 
outside  the  "camera"  and  before  the  lens 
the  different  scenes  were  played.  For  in- 
stance, hunting  parties  were  very  popu- 
lar in  which  the  game  was  represented 
by  disguised  boys  or  wooden  effigies. 
War  scenes  and  passion  plays  were  also 
presented.     At  night   statues   and   large 


Full  Information  on  Sound  Systems 

tubes,   sound   reproducers,  amplifiers,  speakers — 

it's  all  in 

THE  SOUND  TRACK  BOOK  OF  THE  THEATRE 

Price  $10.00 

THE  SOUND  TRACK 

1001  W.  Washington  Blvd.      Chicago  7,  III. 

E.  C.  JOHNSON— Manager,  Wash- 
ington Theatre,  Bay  City,  Michigan 
— says: 

"Our   perfect   sound   is   our 
greatest  asset.  RCA  has  kept 
it  to  that  high  standard." 
To  get  the  benefits  of  RCA  Service- 
write:    RCA   SERVICE   COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


\ 


Wenzel  Presents  . . .  SOUND  HEAD  WSH- 


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full    details   of   the   many   advantages   of  this 
new  WENZEL  product. 

WENZEL    PROJECTOR    CO. 


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Chicago    16,    III. 


INTERNATIONAL  PROJECTIONIST     •     August  1949 


29 


supposing  the  cube  to  be  attached  out- 
side the  room  and  of  supposing  the 
screen  to  be  a  "slide"  for  the  drawings. 
Second,  Porta  was  accredited  with  the 
technique,  which,  however,  was  devel- 
oped long  after  Porta  by  Kircher,  to 
whom  Schott  refers.  Owing  to  the  au- 
thority of  Priestley,  his  mistake  was  re- 
peated in  the  historical  works  of  Joh. 
Carl  Fischer  and  Poggendorff,  and  from 
these  in  the  more  modern  books. 

[To   be  Continued] 


FIG.  2.    The  camera  obscura  in  the  sixteenth  and  seventeenth  centuries. 


pictures    painted   on   canvas   lighted   by 
torches  were  shown. 

In  this  way  the  public  saw  pictures  of 
the  emperor,  scenes  of  the  rising  and 
setting  of  the  moon  and  stars,  and  last 
but  not  least  images  of  the  devil  to 
frighten  the  spectators  who  still  looked 
upon  the  whole  performance  as  an  un- 
canny and  supernatural  affair.  It  must 
be  noted  that  in  its  application  the  cam- 
era obscura  came  quite  near  the  perform- 
ances which  were  given  with  the  "la- 
terna  magica"  some  70  years  later. 

Priestley's    Erroneous    Conception 

When,  in  addition,  the  well-known 
English  chemist  Priestley  (1733-1804)  in 
his  work  on  the  history  of  optics  (1776) 
wrote  that  Porta  also  used  transparent 
drawings  as  "slides,"  the  close  connec- 
tion between  the  projecting  lantern  and 
the  camera  obscura  seemed  to  be  certain, 
and  for  a  long  time  it  was  held  that  the 
former  developed  out  of  the  latter. 

As  has  already  been  mentioned,  a  care- 
ful study  of  the  available  old  literature 
shows  that  another  development  is  more 
probable.  In  Priestley's  description, 
Porta  is  said  to  have  traced  drawings  on 
transparent  paper  attached  to  one  of  the 
sides  of  a  hollow  cube  the  opposite  side 
of  which  was  open  and  turned  to  the 
lens.  From  this  transparent  drawing, 
placed  outside  of  the  room,  an  enlarged 
picture  was  formed  on  the  screen.  The 
necessary  light  came  from  the  sun.  By 
making  the  slide  movable,  Porta  is  said 
to  have  been  able  to  attain  effects  which 
seemed  positively  uncanny  to  his  con- 
temporaries. 

Priestley  further  supposed  that  the 
German  Jesuit,  Athanasius  Kircher,  fol- 
lowing up  on  Porta's  device,  later  in- 
vented the  magic  lantern  (Fig.  1)  which 
did  the  job  of  the  camera  obscura  at 
night.  Thus  Priestley  refers  to  the 
"Magia  Universalis"  (1657)  a  work  of 
Kaspar  Schott,  an  assistant  of  Kircher. 
But,  in  turn,  Schott  refers  to  the  first 
edition  of  Kircher's  "Ars  Magna  Lucis  et 


Umbrae"  of  1646  in  which  the  camera 
obscura  was  described,  and  after  an  ex- 
planation of  the  apparatus  Schott  wrote 
("Magia  Universalis,"  volume  1,  page 
198,  Wurzburg  1657)  : 

"In  order  that  the  spectator  does  not 
notice  the  small  hole  with  the  lens  so 
that  the  effect  is  more  mysterious,  one 
attaches  inside  the  room  in  front  of  the 
lens  a  hollow  cardboard  cube  with  black- 
ened sides,  except  the  side  turned  to  the 
lens,  which  is  open,  and  the  opposite 
side,  which  is  made  of  transparent  paper. 
On  this  transparent  paper  one  projects 
the  image  of  cardboard  objects  placed 
outside  the  room  which  are  turned  upside 
down  in  order  to  get  the  pictures  right 
side  up  on  the  screen.  .  .  ." 

Priestley    thus    made    the   mistake    of 


GLEN  L.  HALL  — Owner,  Hall 

Theatre,  Cassville,  Missouri — says: 

"We  have  never  been  without 

RCA  Service.  I  think  it's  the 

best  insurance  a  theatre  owner 

can  have." 

To  get  the  benefits  of  RCA  Service — 

write:   RCA  SERVICE   COMPANY, 

INC.,  Radio  Corporation  of  America, 

Camden,  N.  J. 


How  Many? 


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INTERNATIONAL  PROJECTIONIST     •     August  1949 


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Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


4  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


S&nd 


(Do  TLoi  (D&lay 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18.  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a  copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
Name  


Address 


I       City 


State 


TEST  YOURSELF  ON  THIS 


: 


1      WHICH  PROJECTOR 
WAS  FIRST  WITH 

REAR 

SHUTTER 

MECHANISM? 


2     WHICH  PROJECTOR 
WAS  FIRST  WITH 

ENCLOSED 
MECHANISM? 


3     WHICH  PROJECTOR 
WAS  FIRST  WITH 

FRAMING  BY 
ROTATING 
SPROCKET? 


4     WHICH  PROJECTOR 
WAS  FIRST  WITH 

SPIRAL 

BEVEL 

GEARS? 


5     WHICH  PROJECTOR 
WAS  FIRST  WITH 

SHOCK-PROOF 
GEARS? 


6     WHICH  PROJECTOR 
WAS  FIRST  WITH 

AUTOMATIC 

FIRE 

TRIP? 


7     WHICH   PROJECTOR 
WAS  FIRST  WITH 

HARDENED 

AND  GROUND 

SPROCKETS? 


8     WHICH  PROJECTOR 
WAS  FIRST  WITH 

REMOVABLE 

FILM 

TRAP? 


9     WHICH  PROJECTOR 
WAS  FIRST  WITH 

DOUBLE 

BEARING 

MOVEMENT? 


10     WHICH   PROJECTOR 
WAS  FIRST  WITH 

SUP-IN 

APERTURE 

PLATE? 


YOU'RE  RIGHT:  THE  ANSWER  IS  ALWAYS 


T.  M.REG.  U.S.  PAT.  OFf. 

PROJECTION  &  SOUND 
FOR  INDOOR  &  DRIVE-IN  THEATRES 


MANUFACTURED     BY     INTERNATIONAL     PROJECTOR     CORPORATION  *BLOOMFIELD,     NEW     JERSEY 


m 


SEPTEMBER 


1949 


VOLUME   24 


NUMBER  9 


30c  A  COPY    •    S2.50  A  YEAR 


What  Makes  Buzzle  wRlte  Like  tH 

is? 


BUZZIE  is  just  learning  to  write. 

And  every  line  he  writes  starts  out  with  big, 
generous  letters  and  ends  up  with  little  squeezed- 
up  ones. 

The  trouble,  of  course,  is  that  he  hasn't  learned 
to  plan  ahead.  He  concentrates  on  making  those 
big  letters,  and  lets  the  end  of  the  line  take  care 
of  itself. 

Many  grownups  have  the  same  trouble  Buzzie 
has— not  with  their  handwriting,  but  with  their 
money. 

They  blow  it  all  at  the  beginning,  when  it  looks 
like  there's  nothing  to  worry  about,  and  let  the 
"end  of  the  line"  take  care  of  itself.  But  it  prac- 
tically never  does. 


That's  why  the  Payroll  Savings  Plan  and  the 
Bond-A-Month  Plan  are  such  a  blessing.  They  are 
"human-nature-proof." 

For  you  don't  have  to  keep  batting  yourself 
over  the  head  to  save  money  when  you're  on  one 
of  these  plans.  The  saving  is  done  for  you— auto- 
matically. 

And  remember,  every  U.S.  Savings  Bond  you 
buy  brings  you  $4  in  ten  years  for  every  $3  in- 
vested. 

So  don't  let  your  life  run  on  like  Buzzie's  hand- 
writing. Fix  up  the  "end  of  the  line"  once  and  for 
all  by  signing  up  today  for  the  Payroll  Savings 
Plan  — or,  if  you  are  not  on  a  payroll,  the  Bond- 
A-Month  Plan  at  your  bank. 


yiutoMAtlc  SAvine  Is  suRe  SAViner  -  U.S.  SaVwgs  Bonos 


Contributed  by  this  magazine  in  co-operation  with  the  Magazine  Publishers  of  America  as  a  public  service. 


\ 


B    2V22«2 


in  Portable 


Sound  Projectors 


Actual  Lift-up  Weight 
Only  20  lbs.! 

The  projector  and 
amplifier  unit  alone 
of   the   new   Ampro 
Stylist  weighs  only 
20  lbs.  A  young  girl 
can   easily   lift   it 
up   to   place  on 
stand    or    table 
Lift-off    case 
with  speake^ 
and     acces 
sories  weighs 
less  than 
9  lbs.! 


Truly  Portable 

Complete  one-case  unit,  in- 
cluding projector,  amplifier, 
lift-off  case  with  speaker 
and  accessories,  weighs 
less   than   29  lbs! 


Quick  Easy  Set-up 

Just  lift  off  case,  snap 
permanently  attached  reel 
arms  in  place  —  and  the 
"Stylist"  is  ready  to  thread. 


HIGHLIGHTS: 

Entire  unit  in  one  case  measures  only 
17y2"  high,  9%"  wide,  16"  long.  Stand- 
ard, time-tested  Ampro  projector  mechan- 
ism and  sound  head.  Fast  automatic 
rewind.  Uses  standard  lamps  up  to  1000 
watts.  Triple  claw  movement,  new  slide-out 
removable  film  gate.  Coated  super  2-inch 
F1.6  lens.  Many  other  exclusive  Ampro 
features. 


A  new  streamlined,  lightweight  projector 

combining  precision  quality,  unusual 

compactness  and  popular  low  price 

The  perfect  16mm.  sound  projector  for  the  home.  Can  be 
set  up  instantly  in  living  room  or  den — carried  easily  for 
outside  use  in  friends'  homes,  clubs,  meetings,  entertain- 
ments— for  use  with  both  sound  or  silent  film.  Here  is  the 
culmination  of  more  than  20  years'  experience  by  Ampro 
in  building  fine  precision  projectors. 

Astonishing  light  weight  and  compactness — made  possible 
by  the  clever  utilization  of  the  new,  tough,  light  materials — 
make  the  Stylist  ideal  for  easy  moving  from  room  to  room 
— for  use  by  small  or  large  groups.  Tested  Ampro  quality 
design  and  construction — assure  ease  of  setting  up,  sim- 
plicity of  operation,  splendid  tone  quality  and  illumination 
and  long,  satisfactory  service.  Remarkable  low  price — $325 
complete  —  means  outstanding  value  and  assures  budget 
approval  in  these  economy  days.  Ask  your  dealer  today  for 
an  eye-opening  demonstration  of  this  new  record-breaking 
Ampro  "Stylist"! 

Write  for  free  circular  giving  full  detailed  "Stylist" 
specifications. 

THE    AMPRO    CORPORATION 
,2865  N.  Western  Avenue,  Chicago  18,  III. 


Simplified 

Operation 
Central  operating  panel, 
with  simplified  knob 
controls,  conveniently 
mounted  on  operator's 
side  of  projector. 


For  Small 
Groups 

Quief-running,  easy  to 
set  up  quickly,  the 
"Stylist"  is  ideal  for 
homes,  clubs  and 
churches.  -    -  - 


Sound  and 
Silent  Speeds 

Offers  true  silent  pro- 
jector operation  with 
variable  speed  control. 


•Trade  Mark  Reg.  U.  S.  Pat.  Off. 


A    Generof    Precision    Equipment 
Corporation    Subsidiary 


INTERNATIONAL    PROJECTIONIST 


September    1949 


/  **  MAGNA 


M. 


£W 


MAGNARC 


TRADE    MARK    REG 


1-KW  TO  70  AMPS 


"HY-AX"  ARC  MAGNET 

HY-LUMEN"   REFLECTOR 


More  light  at  40  to  70  amperes  than  ever  thought  possible. 
.  .  .  Equals  and  excels  any  reflector  lamp  to  85  amperes,  whether 
they  be  unapproved  water-cooled  or  resurrected  hi-lows.  .  .  . 
Highest  ratio  of  screen  lumens  per  watt  consumed  at  the  arc. 
...  At  70  amperes,  with  a  projector  having  an  efficient  DISC 
type  revolving  shutter,  it  develops  the  maximum  white  light  that 
can  be  used  without  a  heat  filter.  .  .  .  Operating  costs  under  these 
conditions  are  far  below  that  of  85-ampere  lamps. 

Magnarc  Lamps  assure  80%  side-to-center  (SMPE  Standard) 
screen  light  distribution,  not  a  deceptive  60%  or  "Hot  Center." 
.  .  .  They  are  all  Und.  Lab.,  Inc.  listed.  .  .  .  They  are  not  in- 
surance hazards.  .  .  .  They  are  and  have  been  for  years  "The 
Standard  of  Comparison"  and  "The  First  Choice"  of  large 
and  small  theatres,  drive-ins,  and  the  motion  picture  industry 
in  general! 


i  i 


ALWAYS  THE  FINEST,  ALWAYS 


1 1 


120-180  AMPERES 


TRADE    MARK   REG. 


NEW    MAGNETIC    STABILIZER 

This  modern  lamp  produces  all  the  light  there  is. 
...  It  is  the  standard  equipment  of  the  nation's  largest 
and  finest  theatres.  .  .  .  Used  by  90%  of  the  largest 
Drive-In  Theatres. 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  white  light  volume 
when  used  with  projectors  that  have  efficient  DISC 
type  revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions.  .  .  .  They  are  Und.  Lab.,  Inc. 
listed  and,  therefore,  not  insurance  hazards. 


I  1 


WHY    EXPERIMENT? 
-J.E.MeAULEY  MFG. CD.- 


i  I 


552-554    WEST   ADAMS    STREET 

CHICAGO  6.  ILLINOIS 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


INTERNATIONAL 

PROJECTIONS! 

With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


SEPTEMBER  1949 


Number  9 


Index  and  Monthly  Chat 5 

Lens  and  Film  Factors  Affecting 
Focus,   II    7 

Robert  A.  Mitchell 

The  'Arcon'  Projection  Arc 

Monitor     10 

VOLNEY  G.  MATHISON 

Questions  and  Answers  on  Safety 
Film    14 

Telecasts    15 

New  Series  of  Lenses  for  16-mm 
Professional   Projection    ....      16 
A.  E.  Neumer 

In  the  Spotlight 18 

Harry  Sherman 


Cooling  Means  for  H-I  Arc  Pro- 
jection        22 

A  Symposium 

Kodak's  New  Ektalite  Lens  ....      24 

New  Graphecon  'Memory'  Tube     30 

News  Projections 31 

Du  Pont's  New  Color  Release 

Positive  Film   32 

Book  Review    33 

News  Notes 

Technical  Hints 

Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING   CO.,   INC. 

19  West  44  Street,  New  York   18,  N.   Y. 

R.  A.   ENTRACHT,   Publisher 

SUBSCRIPTION   REPRESENTATIVES 

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act  of  March  3,  1879.  Entire  contents  copyrighted  1949  by  International  Projectionist 
Publishing  Co.,  Inc.  International  Projectiomst  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


420 


MONTHLY   CHAT 


IT  WAS  observed  in  this  corner  re- 
cently that  there  was  developing  a 
definite  trend  toward  a  much  closer  co- 
operation between,  on  one  hand,  manu- 
facturers and  projectionists — seller  and 
user — and,  on  the  other,  between  the 
manufacturers  themselves.  This  growing 
recognition  of  the  strong  mutuality  of 
interest  which  exists  between  both  groups 
is  one  of  the  most  encouraging  develop- 
ments in  recent  years. 

No  more  tangible  evidence  of  this  new 
spirit  in  the  field  is  needed  than  the 
symposium  on  cooling  methods  for  high- 
intensity  arc  projection  which  appears 
elsewhere  in  this  issue  and  which  reflects 
their  views  of  top-flight  equipment  manu- 
facturers on  this  pressing  problem. 

IP  solicits  the  serious  consideration  by 
its  readers  of  this  symposium,  for  two 
reasons:  that  they  may  be  better  in- 
formed about  the  projection  process,  and 
in  the  hope  that,  drawing  upon  their  day- 
to-day  practical  operating  experience, 
they  may  be  able  to  make  a  significant 
contribution  to  the  solving  of  this  prob- 
lem. 

Ironically,  the  manufacturers  now  find 
themselves  hoist  on  their  own  petard  in 
that  by  striving  assiduously  and  success- 
fully to  meet  the  demands  of  the  field 
for  more  light,  they  now  are  being 
devilled  by  the  end  product  of  their  in- 
genuity and  progressiveness.  It  may  be 
asked  what  the  film  manufacturers, 
whose  product  forms  the  very  core  of 
this  problem,  are  doing  about  the  matter. 
This  group  is  working  feverishly  to  come 
up  with  the  answer — as  attested  to  by 
their  many  contributions  to  the  litera- 
ture thereon — but  unfortunately  even 
their  vast  scientific  resources  have  not 
yet  been  productive  of  a  means  for  mak- 
ing film  heat-resistant  the  while  it  re- 
tains its  full  pictorial  quality. 

Not  often,  if  ever,  have  manufacturers 
of  competitive  projection  products  been 
willing  to  take  down  their  hair,  so  to 
speak,  and  set  forth  in  print  their  views 
on  a  controversial  question  of  this  nature, 
and  this,  to  us,  is  indicative  of  the  seri- 
ousness of  this  problem. 

IP's  suggestion  that  the  SMPE  sponsor 
a  forum  in  which  manufacturers  and 
prominent  projectionists  air  their  views 
on  this  topic  is  militated  against  by  two 
factors:  first,  time  is  of  the  essence  in 
this  matter,  and  such  a  get-together 
would  necessarily  require  restrictions  in 
the  matter  of  attendance.  Obviously,  the 
SMPE  could  not  satisfy  either  of  these 
requirements. 

IP  stands  ready  to  sponsor  such  a 
forum  "on  the  house"  in  terms  of  mak- 
ing all  arrangements  such  as  providing 
a  suitable  meeting,  transcribing  the  rec- 
ord of  the  proceedings,  etc.  Three  manu- 
facturers have  already  indicated  their 
willingness  to  participate  in  such  a 
forum.  All  we  need  is  a  nod  from  the 
others  to  start  the  ball  rolling.  We'll  do 
the  rest. 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


She  keeps  the  romance  running  smoothly... 


THE  spell  of  this  picture's  song  and 
story  might  suddenly  be  broken  .  . .  but 
for  film  row's  "first  lady,"  the  exchange 
inspectress. 

With  unrelenting  vigilance,  she  has 
inspected  every  inch  of  film  before  each 
booking. . .  checked  it  for  worn  perfora- 
tions, torn  splices,  and  other  signs  of 
wear  and  tear  that  might  hinder  smooth 
projection  and  mar  the  enchantment  of 


the  show.  By  this  painstaking  care  of 
film  and  unceasing  effort  to  keep  each 
reel  running  smoothly,  the  inspectress 
has  earned  a  place  of  importance 
behind  the  scenes  of  motion  picture 
distribution. 

And  her  work  is  all  the  more  easily 
done  for  the  quality  and  reliability  she 
finds  in  the  release  prints  made  on 
Eastman  film. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.    Y. 

J.    E.    BRULATOUR,    INC.,   DISTRIBUTORS 
FORT    LEE     •    CHICAGO     •     HOLLYWOOD 


VOLUME  XXIV 


SEPTEMBER  1949 


NUMBER  9 


Lens  and  Film  Factors  Affecting  Focus 


OVER  and  above  the  special  prob- 
lems peculiar  to  the  projection  of 
colored  pictures,  certain  other 
focusing  difficulties  are  common  to  prints 
of  all  types.  These  are  (1)  poor  photo- 
graphic image,  (2)  image  flutter,  and 
(3)  focus  drift.  Little  need  be  said  about 
out-of- focus  pictures  on  the  film;  the  pro- 
jectionist can  do  nothing  to  improve  their 
appearance  on  the  screen.  The  distribu- 
tor, ever  evading  responsibility,  would 
like  to  have  us  believe  that  the  condition 
is  also  beyond  his  control;  so  it  avails 
little  to  complain  about  a  poor  print 
when  the  fault  lies  with  either  the  cam- 
era crew  or  the  processing  laboratory. 

Image  flutter  is  a  rapid  in-and-out-of- 
focus  effect  caused  by  buckled  and 
warped  film.  In  rare  instances  frame- 
embossed  film  gives  a  somewhat  similar 
fluttery  image. 

Buckling  is  caused  by  the  heat  to 
which  the  film  is  subjected  in  the  pro- 
jector. Heat  shrinks  film,  and  if  the 
heating  were  uniform,  the  consequent 
shrinkage  would  be  uniform.  But  in 
passing  through  the  projector  gate  the 
perforation  margins  absorb  more  heat 
than  the  picture  part  of  the  film  because 
of  their  prolonged  contact  with  the  hot 
gate  shoes,  or  runners. 

The  picture  portion  receives  only  a 
momentary  flash  of  radiant  heat  (infra- 
red), and  much  of  this  passes  through 
the  film  with  the  visible  light  instead  of 
being  absorbed.  As  a  result,  the  edges 
undergo  greater  shrinkage  than  any  other 
part  of  the  film.  The  picture  portion  is 
thus  buckled  out  of  shape  so  that  it  flops 
in  and  out  of  focus  during  projection. 

Nitrate  (inflammable)  film  is  much 
more  susceptible  to  the  deleterious  effects 
of  heat  than  the  more  stable  high-acetyl 
acetate    (safety)    film.     Severe   buckling 


By  ROBERTA.  MITCHELL 
II 

and  film  shrinkage  should  be  relatively 
rare  with  the  new  high-acetyl  safety 
film. 

The  projectionist  should  not  attempt 
to  recondition  full-length  reels  of  buckled 
film.  However,  short  rolls  of  buckled  film 
— announcement  and  advertising  trailers, 
for  example — may  easily  be  treated  in 
the  projection  room  with  more  or  less 
success. 

A  buckled  acetate  film  should  be 
wound  in  a  roll  having  the  clear,  or  base, 
side  of  the  film  facing  out.  The  roll  is 
then  placed  in  a  film  can,  the  cover  of 
which  is  fitted  with  a  blotter  lightly  mois- 
tened with  water  containing  glycerine  to 
prevent  drying  out  (1  teaspoonful  of 
glycerine  to  half  a  pint  of  water).  The 
box  is  closed  tightly  and  left  undisturbed 
for  a  week.  If  at  the  end  of  that  time 
traces  of  buckling  remain,  the  treatment 
should  be  repeated. 

A  buckled  nitrate  film  should  be 
wound  with  the  glossy  clear  side  of  the 
film  facing  out.  The  roll  is  placed  in  a 
film  box  having  a  cover  which  is  fitted 
with  a  blotter  heavily  charged  with  cam- 
phor and  also  lightly  moistened. 

Dissolve  a  small  cake  of  camphor  in 
an  ounce  or  two  of  acetone.  Wet  the 
blotter  thoroughly  with  this  solution. 
When  the  acetone  has  completely  evapo- 
rated, the  fibers  of  the  blotting  paper 
will  be  impregnated  with  the  camphor. 
The  dry  camphorated  blotter  may  then 
be  lightly  sprinkled  with  the  water- 
glycerine  mixture  used  for  safety  film. 
The  box  is  tightly  closed  and  left  undis- 
turbed for  a  week  or  more. 

Unfortunately,  there  is  no  way  to  over- 


come the  image  flutter  of  buckled  film 
during  projection.  Increased  gate  ten- 
sion fails  to  relieve  the  trouble. 

The  annoying  and  insidious  phenom- 
enon known  as  focus  drift  is  more  com- 
mon than  is  generally  supposed.  Prints 
having  focus-drift  characteristics  require 
changes  in  focus  during  projection.  Pro- 
gressive focus  drift  is  characterized  by  a 
practically  constant  shift  of  required 
focus.  If  a  reel  having  this  fault  be 
focused  sharply  at  the  beginning,  the 
lens  not  being  subsequently  adjusted,  the 
image  on  the  screen  will  gradually  lose 
its  definition  and  become  considerably 
out  of  focus  by  the  time  the  reel  nears 
its  end. 

Irregular  focus  drift  is  evidenced  by 
random  transient  losses  of  focus  which 
are  truly  perplexing  when  the  film  is  a 
supposedly  uniform  release  print.  Com- 
posite reels  (those  made  up  of  trailers 
or  other  assorted  individual  rolls)  are 
well-known  examples  of  irregular  focus 
drift. 

It  is  almost  impossible  to  detect  the 
presence  of  focus  drift  in  a  reel  of  film 
except  by  actual  projection,  but  all 
"kinky"  films  and  those  having  a  strongly 
set  curl  at  either  beginning  or  end  are 
very  likely  to  offer  trouble  from  this 
cause. 

Buckled  film,  we  have  seen,  is  caused 
by  projection  conditions.  Accordingly, 
prints  fresh  from  the  processing  labora- 
tories are  never  buckled  unless  grossly 
mishandled.  Focus  drift,  contrariwise,  is 
often  present  in  prints  which  are  practi- 
cally brand  new! 

The  immediate  cause  of  focus  drift  is 
film-curl,  a  more  or  less  permanent  defor- 
mation of  the  film  base.  Irregularities  in 
frame  embossing  and  variations  in  film 
thickness    could    also    cause    focus    drift, 


INTERNATIONAL    PROJECTIONIST     •     September   1949 


but  there  are  good  reasons  for  consider- 
ing these  factors  negligible. 

A  progressively  varying  curl  character- 
istic is  "set"  in  the  film  by  winding  it 
too  tightly  on  a  small-hnbbed  reel  and 
by  storing  film  for  a  considerable  length 
of  time  without  rewinding  it  at  intervals 
to  change  the  direction  of  the  film  and 
to  reverse  the  curvature  of  the  convolu- 
tions. New  prints  which  are  laid  away 
for  long-term  storage  are  curl-deformed 
rather  rapidly,  but  in  many  cases  it  is 
better  to  let  the  film  become  curled  than 
to  risk  possible  scratching  by  periodi- 
cally rewinding  it. 

Labs  and  Exchanges  Lax 

An  irregular  curl  characteristic  is  pro- 
duced by  variations  in  the  tension  of  the 
film  in  its  long  and  devious  journey 
through  the  processing  machinery  and 
by  irregularities  in  the  forced  drying  of 
the  emulsion.  In  fact,  the  loss  of  the 
moisture  absorbed  by  the  emulsion  from 
the  developing,  acid  fixing,  hardening, 
and  several  washing  baths  is  not  actually 
complete  for  a  long  time  after  the  film 
looks  and  feels  perfectly  dry. 

New  film  is  soft,  pliant,  susceptible  to 
deformation.  Any  stresses  and  strains  to 
which  the  emulsion  may  be  subjected 
during  the  "curing"  period  will  be  trans- 
mitted to  the  film  base  and  produce  a 
tendency  to  curl.  "As  the  twig  is  bent 
so  will  grow  the  tree"  is  an  adage  ap- 
plicable to  new  film. 

The  correction  of  focus  drift  by  treat- 
ment of  the  film  is  usually  out  of  the 
question  in  the  case  of  full-length  reels. 
The  trouble  would  be  greatly  minimized, 
however,  if  the  film  laboratories  and  ex- 
changes, when  preparing  new  prints  for 
distribution,  would  wind  them  "feet 
first,"  emulsion  side  facing  out,  and  leave 
them  backivards  until  shipped  to  the 
theatres.  The  projectionist  who  "breaks 
in"  the  new  print  should  be  the  first 
person  to  store  it  overnight  in  the  normal 
"head-first"  order  for  showing. 

This  simple  treatment  prevents  a  tend- 
ency toward  curl  deformation  by  delay- 
ing "setting"  of  the  film  convolutions  in 
their  "normal"  curvature,  and  at  a  time 
when  such  a  prophylaxis  is  most  effec- 
tive. Distributors  should  be  especially 
delighted  by  the  fact  that  this  expedient 
doesn't  cost  a  penny. 

Short  rolls  of  film  may  be  "uncurled" 
by  winding  them  up  tightly  in  the  same 
direction  as  they  are  found  (head-first  if 
the  roll  has  been  stored  head-first  for  a 
long  time),  but  with  the  direction  of  the 
emulsion  reversed  to  counteract  the  natu- 
ral curling.  The  rolls  of  film  should  then 
be  secured  with  tight  bands  and  put 
away  for  a  week. 

High-acetyl  acetate  film  is  somewhat 
inferior  to  nitrate  film  in  the  matter  of 


curl-deformation  susceptibility.  Since 
focus  drift  is  a  more  common  evil  than 
buckling  and  image  flutter,  it  is  clear 
that  further  improvements  in  safety  film 
are  needed. 

Focusing  Methods 

Because  focus  may  vary  from  reel  to 
reel  or  even  from  section  to  section  of 
the  same  reel,  it  cannot  too  often  be  re- 
peated that  the  projectionist  must  keep 
a  sharp  eye  on  the  condition  of  the  focus 
if  the  very  best  image  definition  is  to  be 
obtained  at  all  times.  Projectionists  oper- 
ating in  theatres  where  lenses  of  very 
short  focal  length  are  used  will  find  the 
unavoidable  changes  in  the  required  posi- 
tion of  the  lens  especially  bothersome. 

Maximum  working  efficiency  of  the 
lens  is  insured  by  checking  the  focus  at 
the  beginning  and  middle  of  each  reel 
and  at  each  change  in  the  type  of  film 
during  a  reel — from  black-and-white  to 
color,  for  example. 

"Checking  the  focus"  does  not  mean 
testing  the  focus  by  actual  adjustment 
of  the  lens.  Unnecessary  "monkeying" 
with  the  focus  adjustment  is  to  be 
avoided  at  all  costs,  for  the  audience  is 
irritated  to  desperation  by  a  picture 
swinging  in  and  out  of  focus  for  no 
apparent  reason.  The  skilled  projection- 
ist checks  the  focus  with  his  eyes  and 
not  with  his  fingers,  and  he  turns  the 
focusing  knob  to  correct  the  focus — never 
to  test  it! 

Except  in  the  case  of  soft-focus  and 
other  difficult  scenes,  any  deviation  from 
perfect  focus  can  be  perceived  immedi- 
ately by  any  projectionist  with  normal 
eyesight.  When  such  deviation  is  appar- 
ent, the  focus  is  sharpened;  otherwise 
the  lens  is  left  strictly  alone.  And  even 
when  the  focus  is  to  be  sharpened,  an 
attempt  must  be  made  to  do  so  without 
bringing  it  to  the  attention  of  the  audi- 
ence. 

Should  the  picture  for  one  reason  or 
another  fall  considerably  out  of  focus, 
however,  the  lens  should  be  restored  to 
its  correct  position  as  quickly  as  pos- 
sible; the  audience  will  appreciate  the 
alertness  of  the  projectionist. 

A  more  delicate  problem  arises  when 
the  picture  is  only  slightly  indistinct. 
The  question  is  whether  the  projection 
or  the  film  is  at  fault.  In  such  an  event 
the  projectionist  may  rightly  concentrate 
on  improving  matters  (if  they  can  be 
improved),  but  he  must  not  forget  that 
good  projection  is  unobtrusive  projec- 
tion. 

When  the  focus  is  sharpened  skilfully, 
not  even  the  most  eagle-eyed  patron  will 
be  aware  of  the  change  while  it  is  being 
made.  But  the  same  person  will  know 
that  the  projection  is  sparkling,  lifelike, 
and  crystal-clear  even  though  he  be 
wholly  ignorant  of  the  constant  vigilance 


and  untiring  efforts  by  which  the  projec- 
tionist maintains  a  perfect  picture. 

To  obtain  and  maintain  a  perfect  focus 
is  utterly  impossible  when  the  lens  is 
positioned  by  aligning  a  notch  or  mark 
on  the  lens  barrel  with  a  reference  point 
on  the  mechanism.  This  method  is  useful 
for  replacing  a  lens  which  has  been  taken 
out  for  cleaning,  but  it  would  be  a  mis- 
take to  think  that  a  lens  could  be  placed 
in  exact  focal  position  that  way.  A  pic- 
ture can  be  focused  only  by  looking  at 
it  on  the  screen  and  adjusting  the  posi- 
tion of  the  lens  when  required.  There  is 
no  other  way. 

Difficulties  with  Old  Heads 

The  focusing  operation  is  comparative- 
ly easy  with  modern  projector  mechan- 
isms having  precision  micrometer  focus- 
ing devices.  But  smooth  focusing  is  far 
from  easy  with  old-style  mechanisms  hav- 
ing simple  rack-and-pinion  devices  for 
moving  the  lens. 

Only  familiarity  with  the  "feel"  of  the 
focusing  lever  or  pinion  rod  of  the  older 
heads  will  enable  the  projectionist  to 
focus  without  overshooting  the  correct 
position  and  thereby  inviting  audience 
attention  to  the  process.  The  installation 
of  a  new  rack-arm  friction  spring  on  the 
Simplex  Regular  (part  no.  S-343-A) 
sometimes  helps  when  the  lens-mount 
slide  is  too  loose  or  jerky  in  action.  Ab- 
solute cleanliness  and  mild  lubrication 
of  the  moving  parts  of  the  focusing 
device  is  extremely  desirable. 

Projector  manufacturers,  in  an  effort 
to  modernize  old-style  heads,  have  pro- 
vided micrometer  focusing  attachments 
to  replace  the  original  pinion  focusing 
knob  and  handle  (pinion  rod).  The 
writer's  experience  with  these  attach- 
ments has  not  been  satisfactory.  There 
i-<  far  too  much  blacklash  and  lost  motion 
in  the  train  of  moving  parts  between  the 
focusing  knob  and  the  lens-holder  slide 
to  permit  a  prompt,  smooth  movement  of 
the  lens.  The  knob  may  be  turned  through 
a  considerable  part  of  a  complete  revolu- 
tion before  the  lens-holder  slide  "takes 
up."  When  at  last  the  lens  does  move, 
it  may  be  found  that  the  knob  has  been 
turned  in  the  wrong  direction,  necessi- 
tating a  repetition  of  the  tedious  process 
in  reverse. 

Wear,  Maladjustment  Affects  Focus 

Projectionists  who  are  accustomed  to 
those  attachments  and  like  them  should 
keep  on  with  them,  but  those  who  find 
them  more  or  less  of  a  nuisance  should 
not  hesitate  to  replace  them  with  the 
original  pinion-knob  and  rod  assemblies. 

Wear  and  maladjustment  of  the  pro- 
jector mechanism  may  have  serious  ef- 
fects on  the  optical  performance  of  the 
lens.  The  condition  of  the  film  trap,  or 
(Continued  on  page  26) 


INTERNATIONAL    PROJECTIONIST 


September    1949 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


IF  THE  consumption  of  human  nervous 
energy  could  be  measured  in  ergs  or 

some  other  scientific  unit,  the  ensuing 
tabulations  would  disclose  that  enormous 
amounts  of  it  are  used  up  daily  at  the 
trying  job  of  watching  the  arcs  in  the 
world's  theatre  projection  rooms.  The 
projectionist  has  a  variety  of  exacting 
duties,  but  most  of  these  tasks  occur  at 
spaced  intervals;  whereas  the  necessity 
for  keeping  "half  an  eye"  on  the  arc  puts 
an  unceasing  strain  on  the  projectionist, 
whether  he  be  aware  of  it  or  not,  from  the 
moment  the  show  starts  until  it  breaks. 

The  writer,  an  "operator"  since  the 
days  of  the  calcium  light  and  the  hand- 
crank,  made  up  his  mind  several  years 
ago  that  there  must  be  some  way  of  free- 
ing projectionists  from  the  harassment 
caused  by  the  antics  of  inherently  un- 
stable projection  arc  lamps.  As  we  all 
know  too  well,  a  pair  of  lamps  will  burn 
perfectly  for  hours;  then,  just  when  the 
projectionist  gets  busy  attending  to  some 
duty,  an  arc  carbon  will  take  off  in  one 
direction  or  another,  and  up  comes  those 
exasperating  three  buzzes  from  some  one 
downstairs  to  indicate  that  the  picture 
has  become  blue  or  brown,  or  possibly 
has  entirely  disappeared  from  the  screen. 

The  writer's  first  arc  monitor  was  a 
cumbersome  and  costly  rig,  comprising 
a  metal  box  with  a  phototube  erected  on 
each  lamp,  with  wires  strung  from  there 
to  an  amplifier  cabinet,  and  a  dynamic 
speaker  which  sometimes  gave  forth  with 
a  signal  when  an  arc  got  out  of  optimum 
position.  This  outfit  was  hard  to  adjust 
and  was  broad  in  its  action.  In  short, 
hardly  anyone  could  use  it  but  its  in- 
ventor. 

About  this  time,  the  author  was  boom- 
ing around  in  Mexico  and  there  fell  in 
with  some  gentry  who  engaged  him  to 
develop  a  black-light  signalling  outfit  for 
llie  purpose  of  secretly  flashing  informa- 


*  Seven    patent    claims     on     this    invention    were    al- 
lowed  by  the  U.   S.   Patent  Office   on   August  5,   1919. 


The    Arcon' 

Projection  Arc 

Monitor* 


By  VOLNEY  G.  MATHISON 

Accurate  control  of  the  feeding  of  the  carbon  arc  has 
long  intrigued  some  of  the  best  engineering  minds;  but, 
significantly,  the  most  notable  contributions  to  the  solu- 
tion of  this  vexing  problem  have  been  made  by  those  with 
practical  day-to-day  projection  experience.  Described 
herein  is  another  contribution  from  the  ranks  of  practi- 
cal workers  in  the  art  which,  already  used  in  a  number  of 
theatres  on  the  Pacific  Coast,  merits  serious  considera- 
tion   by    all    concerned    with    the    projection    process. 


White   line   indicates  path    of  actuating    light- 
beam  to  monitor  which  is  mounted  above  and 
to  the  right  of  projection  port. 


tion  out  of  Mexican  racetracks.  In  the 
course  of  developing  the  black-light  ap- 
paratus, it  suddenly  became  apparent 
that  some  of  the  color  filters  and  other 
things  used  in  the  racetrack  gadgets 
might  be  applied  to  the  projection  arc 
monitor. 

Spectral  Characteristics  Required 

Phototubes  with  the  so-called  S-l  type 
of  cathode,  such  as  the  918,  have  two 
sensitive  peaks,  one  in  the  violet  end  of 
the  visible  light  spectrum  around  360 
millimicrons,  and  the  other  in  the  infra- 
red, peaking  at  800  millimicrons. 

As  is  apparent  on  the  indicator  card 
of  any  Suprex  arc  lamp,  the  area  of  the 
arc  between  the  negative  carbon  and  the 
gass  ball  emits  a  good  deal  of  light  at 
frequencies  corresponding  to  violet  and 
blue.  Viewing  the  arc  through  various 
color  filters  discloses  that  the  gas  ball 
gives  out  a  light  of  mixed  frequencies — 
that  is,  a  "white"  light — while  the  crater 
rim  of  the  positive  carbon  emits  an  in- 
tense radiation  at  frequencies  corre- 
sponding to  a  very  deep  red. 

Hence  the  writer  conceived  the  idea 
of  placing  color  filters  in  the  auxiliary 
beam  of  light  used  to  actuate  the  photo- 
tube of  an  arc  monitor,  the  filters  being 
of  a  type  to  cut  off  all  but  deep  red 
light.  This  scheme  resulted  in  a  great 
improvement  in  the  selectivity  of  the 
monitor,  since  the  violet  and  blue  light 
in  the  space  between  the  negative  carbon 
and  the  gas  ball  was  effectively  screened 
out,  and  only  the  light  from  a  more 
limited  area  of  the  arc  could  get  through 
to  hold  in  the  phototube  apparatus. 

This  arrangement  was  nonetheless  un- 


successful, since  the  strong  red  and  infra- 
red light  used  to  operate  the  instrument 
proved  to  be  highly  destructive  both  of 
filters  and  phototube  cathode  surfaces. 
Also,  the  device  was  still  just  a  one-way 
monitor — that  is,  it  would  warn  the  pro- 
jectionist only  when  the  positive  carbon 
began  burning  too  far  away  from  the 
lamphouse  mirror,  producing  a  blue  pic- 
ture. 

Filtering  Infra-red  Emanations 

It  worked  fine  in  this  respect,  but  when 
the  positive  carbon  was  overfed  and 
began  burning  toward  the  lamp  mirror, 
producing  a  brownish  light  on  the.  pic- 
ture, the  monitor  merely  sat  tight  and 
did  nothing.   No  signal. 

Further  study  of  Suprex  arcs  revealed 
that  the  reason  for  this  was  that  the  en- 


Commercial  model  of  the  Arcon  monitor,  actual 
size  of  which  may  be  determined  in  photo  of 
projection  room  at  left.  Small  discs  shown  at  top 
of  Arcon  above  controls  pick  up  actuating  light- 
beams   from   projectors   1    and   2,   respectively. 


10 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


tire  end  of  the  hot  positive  carbon  emits 
a  powerful  infra-red  radiation  extending 
back  as  much  as  x/g,  inch  from  the  rim 
of  the  arc  crater.  Since  the  standard 
phototube  with  the  S-l  type  of  cathode 
is  highly  sensitive  to  this  infra-red  radia- 
tion, it  refuses  to  indicate  a  weakening 
light  when  it  is  "looking  at"  the  hot  red 
side  of  the  end  of  a  positive  carbon. 

A  search  began,  therefore,  for  some 
means  of  cutting  off  sharply  the  infra-red 
frequencies  radiated  by  the  positive  car- 
bon. Laboratory  types  of  anti-infra-red 
filters  are  common,  but  the  most  efficient 
ones  are  wet-cell  in  form  and  impracti- 
cable for  use  in  a  projection  arc  monitor. 
Others  are  made  of  gelatin  and  tend  to 
fade  out  under  prolonged  exposure  to  an 
infra-red  beam.  Various  combinations 
were  tried  without  satisfactory  results. 

But  one  day  the  writer  picked  up  a 
piece  of  Mexican  jewelry  made  of  pale 
greenish  beryl — a  variety  of  emerald — 
and  experimentally  stuck  it  into  the  light 
beam  between  a  projection  arc  and  a 
monitor.  The  results  were  magical!  The 
selective  action  of  the  monitor  was  hard 
and  crisp,  and  equally  so  against  either 
blue  or  brown  light.  The  infra-red  radia- 
tion of  the  positive  carbon  was  blocked, 
or  at  least  greatly  reduced,  and  only  the 
brilliant  visible  red  light  at  the  extreme 
rim  of  the  crater  of  the  positive  carbon 
was  getting  through  to  the  phototube. 

Photographs  of  a  projection  arc  taken 
through  compound  filters  made  up  of  the 
original  anti-blue  filters  and  the  new 
beryl  filter  revealed  an  image  resembling 
a  sharp  white  line  less  than  l/40th  inch 
in  width  at  right  angles  to  the  axis  of 


FIGURE  1 


the  positive  carbon.  This  was  actually  a 
picture  of  the  extreme  edge  of  the  gas 
ball  where  it  lies  in  contact  with  the 
positive  carbon.  The  color  filters  blocked 
the  radiation  from  all  other  portions  of 
the  arc — that  is,  to  a  relative  degree, 
which  is  all  that  is  required. 

The  source  of  the  beryl  that  stopped 
the  infra-red  light  was  investigated  and 
it  was  found  that  the  mineral  came  from 
the  slopes  of  an  extinct  volcano.  For  a 
time  filters  were  made  up  of  this  mineral, 
but  it  was  extremely  hard  to  work,  hav- 
ing to  be  sliced  up  with  a  diamond  saw. 
Samples  were  eventually  burned  in  a 
spectroscopic  arc  and  the  metallic  ele- 
ments responsible  for  the  anti-infra-red 
action  were  determined.  An  infused  man- 
ufactured plate  glass  of  equivalent  char- 
acteristics is  now  used  in  the  monitor 
filters. 

'Reduction  to  Practice 

With  these  rather  big  things  to  work 
with,  the  inventor  thought  his  project 
was  nearly  completed;  but  this  was  not 
the  case.  It  still  was  necessary  to  make 
what  the  patent  office  calls  "reduction  to 
practice,"  which  in  plain  "Skidrow"  Eng- 
lish means  taking  the  bugs  out  of  the 
gimmick  and  producing  a  usable  com- 
mercial device. 

This  involved  the  development  of  a 
rugged  and  reliable  photoelectric  ampli- 
fier of  a  type  that  would  operate  on  a 
gradual  change  in  intensity  and  quality 
of  the  arc  light  and  at  the  same  time 
not  respond  to  the  momentary  flickerings 
that  constantly  occur  ownig  to  impurities 
or  traces  of  moisture  in  the  carbons.  The 
usual  types  of  amplifiers  that  would 
respond  to  a  continuous  unmodulated 
light  beam  were  without  exception  costly 
and  unstable. 

This  problem  was  finally  solved  through 
the  use  of  a  mixer-amplifier  tube  in  the 
first  stage  of  the  circuit,  the  suppressor 
grid  of  this  tube  being  fed  a  modulating 
voltage  from  a  separate  oscillator,  so 
that  a  sort  of  one-sided  superheterodyne 
action  is  obtained.  From  here  on  amplifi- 
cation is  obtained  by  conventional  resist- 
ance-condenser coupling  circuits,  termi- 
nating in  an  a.c.-operated  signal  vibrator. 

Other  circuits  have  since  been  devel- 
oped, including  one  whereby  the  monitor 
functions  only  when  a  picture  is  being 
run,  the  instrument  automatically  turn- 
ing itself  off  during  intermissions  and  at 
the  end  of  the  show. 

Details  of  Unit  Operation 

The  schematic  design  of  the  basic  in- 
vention is  shown  in  Fig.  1,  which  is  a 
partial  copy  of  the  original  patent  appli- 
cation drawings.  In  this  illustration 
(which  is,  of  course,  non-proportional), 
the  two  projection  arcs  are  represented 
at  25.  A  light-hole,  24,  is  drilled  in  each 


FIGURE  2 

lamphouse  above  the  arc,  so  that  a  line 
drawn  from  the  arc  to  the  hole  is  as 
nearly  as  possible  at  a  right  angle  to  the 
axis  of  the  positive  carbon.  It  is  not 
usually  possible  to  get  the  light-hole  pre- 
cisely at  a  right  angle  to  the  carbon  tip 
and  axis  because  of  interference  from 
mirror-shield  paddles  and  levers  in  arc 
lamphouses.  In  such  cases  the  actual 
location  of  the  light-hole  is  slightly  for- 
ward of  the  arc,  but  must  be  no  more 
than  is  absolutely  necessary  to  afford  an 
unobstructed  view  of  the  arc  from  the 
hole. 

The  light  beam  emerging  from  the 
light-hole  strikes  a  mirror,  26.  This  mir- 
ror is  cemented  onto  a  ball-and-socket 
fitting  which  is  mounted  in  a  second  hole 
drilled  into  the  sheet  metal  top  of  the 
lamphouse.  The  actual  location  of  the 
light-hole  and  mirror  is  up  on  the  top 
side  of  each  lamphouse,  directly  at  the 
side  of  the  chimney  in  the  Brenkert  and 
the  Magnarc  lamps,  and  toward  the  rear 
of  the  chimney  in  Ashcraft  lamps. 

Paper  templets  are  supplied  showing 
the  correct  location  of  the  light-holes: 
without  these  it  is  rather  difficult  for 
anyone  but  an  experienced  installer  to 
get  them  in  the  right  place. 

The  light  reflected  from  each  ball-and- 
socket  mirror  strikes  one  of  the  adjust- 
able shutters,  12,  of  the  monitor.  The 
shutters  shown  in  the  illustration  have  a 
linear  series  of  perforations,  this  con- 
struction having  been  used  to  protect  the 
fragile  gelatin  filters  that  were  at  first 
used  in  the  system.  After  the  develop- 
ment of  plate  glass  anti-infra-red  filters, 
this  type  of  shutter  was  replaced  by  an- 
other having  a  single  long  slot  instead 
of  a  row  of  small  slots.  The  action  is 
identical  in  either  case. 

'Intensity  Equalizer1  Developed 

Secured  onto  the  back  of  each  shutter 
is  the  compound  color-filter  assembly,  16. 
Mounted  horizontally  behind  and  some- 
what above  the  shutters  is  a  phototube, 
17.  The  phototube  actuates  the  amplifier 
and  associated  signal  vibrator  circuit. 

Figure  2  shows  in  detail  the  orifice  and 
the  path  followed  by  the  light  beam. 

Not  shown  is  a  recently  developed 
"intensity  equalizer,"  consisting  of  an  ad- 
ditional rotatable  variable-density  filter, 


INTERNATIONAL    PROJECTIONIST 


September    1949 


11 


FIGURE  3 


FIGURE  4 


FIGURE  5 


FIGURE  6 


whereby  light  beams  of  differing  intensi- 
ties from  a  pair  of  lamps  are  matched  up 
inside  the  amplifier  cabinet.  Previously, 
it  was  necessary  to  match  up  the  light 
beams  by  carefully  reaming  the  light- 
holes  in  the  lamphouses  until  the  re- 
sponse of  the  monitor  was  the  same  on 
either  lamp. 

By  rotating  the  equalizer  control,  0~e 
monitor  can  be  caused  to  respond  to 
either  lamp  with  equal  sharpness,  regard- 
less of  differing  intensities  of  the  two 
light  beams  projected  alternately  onto 
the  monitor  shutters. 

As  shown  in  Fig.  3,  the  image  of  the 
end  of  a  postive  carbon  is  aligned  on 
the  slots  in  a  shutter,  the  shutter  being 
rotated  and  clamped  so  that  the  slot  line 
is  at  a  right  angle  to  the  lengthwise  axis 
of  the  carbon  image. 

If  the  positive  carbon  now  burns  to- 
ward the  main  lamphouss  mirror,  the 
image  on  the  slots  will  move  toward  the 
position  indicated  in  Fig.  4,  resulting  in 
a  reduction  of  intensity  of  light  reaching 
the  phototube ;  consequently  the  monitor 
operates  and  produces  a  signal.  If  the 
carbon  moves  away  from  the  main  lamp- 
house  mirror,  the  image  on  monitor  shut- 
ter moves  toward  the  position  shown  in 
Fig.  5.  likewise  causing  a  signal. 

Equally  important,  if  a  carbon  lurns 
off  crookedly,  as  indicated  in  Fig.  6,  its 
image  will  become  misaligned  with  the 
shutter  slots,  reducing  the  amount  of 
light  reaching  the  phototube,  and  the 
monitor  will  operate. 

Negative  Carbon  Control  Data 

The  monitor  does  not  respond  directly 
in  the  case  of  the  negative  carbon  moving 
forward  toward  the  positive  carbon.  A 
monitor  that  closely  watches  the  negative 
as  well  as  the  positive  carbon  has  been 
built;  however,  it  defeats  the  main  pur- 
pose of  the  invention,  as  it  makes  such 
exacting  demands  for  perfect  adjustment 
of  both  electrodes  thai  on~  -  nnot  ^ave 
the  lamp  for  any  length  of  time.  Hence 
only  the  positive  carbon  is  monitored; 
this  is  the  actual  source  of  the  light. 

Nonetheless,  the  monitor  is  very  sensi- 
tive to  misalignment  of  the  negative  car- 
bon   upward,     downward,     sidewise,     or 


backward.  In  all  such  cases,  the  image 
on  the  shutter  will  develop  a  misalign- 
ment similar  to  that  indicated  in  Fig.  6 
and  the  monitor  will  operate.  In  fact  the 
monitor  gets  very  mad  and  cranky  when 
a  pair  of  carbons  are  misaligned  in  any 
way,  and  will  not  quiet  down  until  the 
positive  carbon  has  been  squared  off  and 
a  good  crater  once  more  formed. 

Dual-Circuit  Unit  Elective 

Projectionists  who  have  not  actually 
used  one  of  the  monitors  occasionally 
express  concern  over  the  fact  that  the 
instrument  does  not  directly  "watch"  the 
negative  carbon.  The  answer  to  this 
point  has  three  aspects:  (a)  a  four-shut- 
ter, dual-circuit  monitor  that  watches 
both  carbons  separately  is  available  at  a 
price  50%  above  the  regular  model;  (b) 
purchasers  are  asked  to  try  the  regular 
model,  at  least  for  a  few  days,  in  order 
to  "get  used"  to  it,  with  the  option  of 
then  exchanging  it  for  the  dual-circuit 
model  if  they  wish;  (c)  up  to  the  present 
time  not  one  user  has  shown  the  least 
desire  to  make  the  exchange. 

The  monitor  functions  on  a  basis  of 
both  correct  color  and  maximum  inten- 
sity of  the  light.  It  insists — with  an  ad- 
justable tolerance — upon  that  adjustment 
of  both  carbons  which  affords  optimum 
registry  of  the  picture  actually  being  pro- 
jected. The  ability  of  the  instrument  to 
do  this  with  a  single  pair  of  slots  is 
largely  due  to  the  use  of  color  filters; 
this  is  one  of  the  basic  features  of  the 
invention. 

Extreme  Sensitivity  Cited 

The  monitor  amplifier  has  two  sensi- 
tivity controls,  one  in  the  first  stage  and 
another  in  the  second  stage.  By  manipu- 
lating these  controls,  the  overall  selec- 
tivity of  the  instrument  can  be  adjusted 
to  any  degree  of  sharpness  or  broadness 
desired.  When  burning  stubs  in  carbon- 
savers,  a  somewhat  broader  adjustment 
is  necessary  than  when  burning  clean 
carbons,  as  the  light  is  usually  a  trifle 
off-quality  with  the  stubs,  and  the  moni- 
tor immediately  detects  this  fact. 

This  device  is  really  a  simplified  and 
streamlined  adaptation  of  an  optical-elec- 
tronic, light-signal  receiving  instrument 
that  (the  learned  engineering  consultants 


estimate)  cost  $6500  to  build  and  is  of 
such  sensitivity  and  selectivity  that  it  will 
respond  to  the  flame  of  a  match  burning 
at  a  distance  of  2000  feet — in  bright  sun- 
light! 

The  learned  engineers  also  said  that  it 
was  impossible  to  build  an  effective  dual- 
arc  projection  monitor  to  sell  for  a  penny 
less  than  $500;  but  the  writer,  fortunate- 
ly, was  blissfully  unaware  of  this  "ex- 
pert" opinion — which  is  why  West  Coast 
theatres  have  installed  these  units  at  a 
cost  of  only  $86.50 

The  Arcon  provides  the  art  and  the 
craft  of  projection  with  a  proven  precise 
means  for  eliminating  a  serious  operating 
defect  of  altogether  too  long  standing. 

Proper  Use  of  Electric  Tools 

Words  of  advice  that  never  lose  their 
timeliness  are  these  four  injunctions  anent 
the  use  of  electric  tools,  as  published  in  the 
Electrical   Workers'  Journal: 

1.  Use  only  equipment  in  good  condition 
and  take  good  care  of  it.  Neglect  may  cost 
a  life — perhaps  yours. 

2.  Be  sure  any  portable  tool  is  properly 
"grounded."    This  "ground"  is  your  life  line. 

3.  Beware  of  bad  insulation,  bad  connec- 
tions, defective  plugs,  unsafe  switches,  spark- 
ing brushes. 

4.  Never  use  an  electric  tool  in  the  pres- 
ence of  flammable  or  explosive  vapors  unless 
especially  designed  for  such  use. 

5.  Never  overstrain  an  electric  tool,  thus 
overloading  the   motor. 

Even  110  kills  now  and  then! 


Projection  of  Industrial  Films 

Projectionists  who  are  active  in  the  pro- 
duction and  showing  of  16-mm  industrial 
films  will  be  interested  in  the  28-page  book- 
let offered  by  Ampro  Corp.  which  gives 
detailed  information  about  the  various 
aspects  of  this  rapidly-growing  field.  Thou- 
sands of  these  booklets  have  gone  out  to 
industrial  firms,  thus  it  would  seem  to  be 
politic  that  projectionists  be  equally  well 
informed  about  their  daily  work. 

In  addition  to  various  commercial  aspects 
of  the  industrial  film  field — such  as  the 
booking  (rental  and  purchase)  of  films,  the 
requisite  facilities  for  showing — the  booklet 
offers  not  a  little  technical  information 
which  will  aid  in  making  a  good  show  better. 
Address  Ampro  Corp.,  2835  N.  Western  Ave., 
Chicago  18. 


12 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


The  term  "National"  is  a  registered  trade-  mark  of 

NATIONAL  CARBON  COMPANY,  INC. 

Unit  of  Onion  Carbide  I'm  and  Carbon  Corporation 
30  East  42nd  Street,  New  York  17,  N.Y. 

Division  Sales  Offices:  Atlanta,  Chicago,  Dallas, 
Kansas  City,  New  York,  Pittsburgh,  San  Francisco 


with  "NATIONAL"  HIGH  INTENSITY 
PROJECTOR  CARBONS 
and  make  box  office 

BOOM! 


-^T 


INTERNATIONAL    PROJECTIONIST 


September    1949 


Questions  and  Answers  on  Safety  Film 


THE  appended  questions  and  answers 
regarding  Safety  Film  (the  improved 
acetate  stock  known  as  High  Acetyl  Film 
which  is  now  in  circulation)  was  pre- 
pared by  Eastman  Kodak  Co.  for  dis- 
tribution among  motion  picture  studio 
safety  engineers. 

What  is  Safety  Film? 

The  American  Standards  Association 
defines  Safety  Film  as  follows:  "Photo- 
graphic films  are  classified  as  safety- 
photographic  film  if  they  are  difficult  to 
ignite,  slow-burning  and  low  in  nitrogen 
content.  It  defines  in  ASA  Z38-3.1,  1943, 
the  laboratory  methods  of  test  and  analy- 
sis for  determining  whether  a  given  film 
conforms  with  this  standard. 

What  is  the  Fire  Hazard 
of  Safety  Film? 

Underwriters  Laboratory,  in  its  "List 
of  Inspected  Gas,  Oil,  and  Miscellaneous 
Appliances,"  lists  the  various  makes  of 
Safety  Film  as  "slow-burning"  and  states 
that  the  "fire  hazard  of  these  products 
in  use  and  storage  is  judged  to  be  of  the 
same  order  as  that  presented  by  common 
newsprint  paper  in  the  same  form  and 
quantity." 

What  is  It  Made  of? 

The  base  is  made  by  combining  cotton 
or  wood  pulp  with  acetic  acid,  the  acid 
found  in  vinegar.  Propionic  or  butyric 
acids,  which  are  very  similar,  are  some- 
times used  in  conjunction  with  the  acetic 
acid.  The  products  are  called  cellulose 
acetate,  cellulose  acetate-propionate,  or 
cellulose  acetate-butyrate. 

Will  Safety  Film  Burn? 

Yes.  Safety  Film  will  burn  if  ignited 
with  a  match  or  other  source  of  flame. 
Generally,  it  will  go  out  of  its  own  ac- 
cord, but  if  it  is  in  a  loose  pile  it  may 
hum  almost  as  rapidly  as  paper. 

If  It  Burns,  Why  Call  It 
Safety  Film? 

The  term  "safety"  is  generally  used  in 
a  comparative  sense.  When  the  old  high- 
wheeled  bicycle  was  replaced  by  the 
modern  bicycle,  the  latter  was  called  a 
"safety"  bicycle.  It  was  obviously  safer 
than  the  old  "high-wheeler." 

Safety  razors  are  so  called  not  because 
one  cannot  cut  oneself  but  because  the 
danger  of  a  bad  cut  is  less  than  with  the 
old  straight  razor.  In  the  same  way  the 
term  "safety  film"  has  been  used  for  a 
long  time  to  differentiate  the  very  much 
safer  acetate  film  from  the  more  danger- 
ous nitrate  film. 

What  Hazards  Does  Safety 
Film  Avoid? 

Safety  film  avoids  the  principal  hazard 


of  nitrate  film.  Nitrate  film  burns  very 
rapidly  indeed.  When  a  roll  is  thorough- 
ly ignited  it  cannot  be  extinguished  with 
a  fire  extinguisher  nor  even  by  immersoin 
in  a  bucket  of  water.  This  is  because  it 
carries  its  own  oxygen  supply  within 
itself  in  the  form  of  the  nitrate  group. 

Nitrate  film  can  be  very  easily  ignited. 
Even  a  glowing  cigarette  can  ignite  it. 
When  burning  with  a  restricted  supply 
of  air,  it  gives  off  fumes  which  are  ex- 
tremely toxic.  Safety  film  avoids  all  these 
hazards. 

Although  Safety  Film  will  burn,  it 
burns  very  slowly.  Generally,  it  will  go 
out  of  itself  unless  it  is  piled  loosely  on 
the  floor  so  as  to  be  in  a  very  favorable 
condition  for  burning.  It  can  easily  be 
put  out  by  smothering  it  with  water,  or 
even  by  blowing  it  out. 

Does  Safety  Film  Introduce 
Any  New  Hazards? 

Yes.  It  introduces  the  hazard  of  care- 
lessness. This  hazard  will  not  be  great 
until  most  nitrate  film  is  replaced  by 
Safety  Film.  When  the  time  comes  that 
nearly  all  pictures  are  on  Safety  Film, 
strict  observance  of  regulations  will  be 
relaxed;  usual  precautions  will  not  be 
taken.  At  that  time  an  occasional  reel 
of  nitrate  film  may  find  its  way  into  a 
projector  that  is  not  properly  maintained, 
and  a  disastrous  fire  may  occur. 

A  portion  of  a  reel  of  Safety  Film  may 
become  damaged  and  a  replacement  be 
spliced  in.  The  replacement  might  be  on 
nitrate  film.  This  reel  might  be  run 
under  projection  conditions  not  suitable 
for  nitrate  film.  The  danger  is  obvious. 

What  Are  the  Best  Means 
to  Avoid  This  Danger? 

Very  few  dangers  are  really  bad  if 
they  are  thoroughly  recognized  and 
understood.  Constant  attention,  educa- 
tion, and  publicity  are  the  best  safe- 
guards. 


Does  Safety  Film  Give  Off  Dangerous 
Gases  When  It  Does  Burn? 

The  smoke  given  off  by  Safety  Film 
when  it  burns  or  when  it  is  roasted  by 
an  external  source  of  heat  is  somewhat 
more  irritating  than  ordinary  wood 
smoke.  It  is  not  more  dangerous  than 
the  smoke  generated  in  ordinary  types 
of  fires. 

How  Can  You  Tell  Whether  Film 
is  Nitrate  or  Safety? 

The  manufacturers  print  their  com- 
pany name  together  with  the  words 
"Safety  Film"  between  the  perforations 
and  one  edge  of  the  film.  This  is  not 
visible  until  the  film  is  developed.  Then 
it  shows  up  in  sharp  black  letters. 

Inexperienced  people  are  often  misled, 
however,  because  of  the  fact  that  in  mo- 
tion picture  work  images  are  transferred 
from  one  film  to  another.  Thus  the  letter- 
ing that  appeared  on  the  negative  film 
in  black  would  appear  on  the  positive  in 
white.  This  makes  it  possible  for  the 
words  "Safety  Film"  actually  to  be 
printed  on  nitrate  film. 

The  one  sure  test  is  the  burning  test. 

Can  the  Burning  Test 
be  Made  Safely? 

Yes.  It  can  be  made  safely  but  only 
if  the  right  precautions  are  taken.  The 
burning  test  should  never  be  made  in  the 
same  room  where  film  is  kept.  It  should 
never  be  made  on  film  in  a  roll,  or  even 
on  a  large  piece  of  film. 

A  single  frame  should  be  cut  from  the 
roll.  This  piece  of  film  should  be  taken 
to  another  room  where  there  is  no  fire 
hazard.  It  should  then  be  ignited  with  a 
match. 

Any  one  familiar  with  the  way  nitrate 
film  burns  can  immediately  tell  whether 
it  is  nitrate  or  acetate.  Nitrate  film  burns 
fiercely,  while  acetate  film  burns  quietly 
and  may  even  go  out  of  itself.  A  glowing 
cigarette  can  burn  a  hole  in  acetate  film 
without  igniting  it,  while  nitrate  is  almost 
always  ignited. 


The  new  G-K  21  projector 
which  is  regarded  in  British 
technical  circles  as  the  "last 
word"  in  motion  picture  pro- 
jection. Not  a  few  of  these 
units  are  now  functioning  in 
Canadian  theatres.  IP  hopes  to 
present  soon  a  detailed  descrip- 
tion of  this  Kalee  mechanism  as 
compared  directly  with  compo- 
nents   of    American    projectors. 


14 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


SAAPE  Asks  60  Channels  for  Theatre  Tv;  RCA  Color  Tv 


HIGHLIGHTING  the  past  month's  de- 
velopments in  the  television  field  was 
the  filing  by  the  Society  of  Motion  Pic- 
ture Engineers,  on  behalf  of  the  motion 
picture  industry  generally,  of  the  answers 
to  the  series  of  questions  posed  recently 
by  the  Federal  Communications  Com- 
mission in  connection  with  the  establish- 
ment of  a  nation-wide  theatre  Tv  service; 
and  the  announcement  by  RCA  that  it 
had  perfected  a  system  of  color  Tv  which, 
by  means  of  an  attachment,  could  be  re- 
ceived by  existing  home  Tv  sets. 

The  SMPE's  statement  set  forth  that  a 
theatre  Tv  network  would  be  important 
because  it  would  provide,  among  other 
things,  instantaneous  communication  ser- 
vice to  a  large  segment  of  the  American 
people  and  during  times  of  emergency 
would  be  available  for  exploitation  in 
the  interests  of  public  morale  and  govern- 
ment service.  As  such,  the  service  would 
be  totally  unrestricted  as  to  particular 
groups,  serving  the  public  at  large.  For 
these  reasons,  the  potentialities  of  theatre 
Tv  should  be  studied  carefully  by  the 
government  and  should  be  supported  in 
the  interests  of  aiding  a  new  industry. 

60  Channels  for  Quality  Image 

Programs  would  be  picked  up  from 
remote  field  locations,  Tv  studios  or  thea- 
tres, sent  to  a  central  studio  or  transmit- 
ter, being  then  distributed  to  theatres. 
R.f.  channels  would  be  required  to  carry 
the  picture  and  sound  from  point  of 
origin  to  theatres  either  on  a  local  basis, 
between  nearby  cities,  or  on  a  nation- 
wide basis,  depending  upon  its  commer- 
cial success. 

Believing  that  picture  quality  would 
have  to  be  ultimately  as  good  as  motion 
pictures  are  today,  the  SMPE  recom- 
mended that  the  FCC  provide  wide 
enough  channels  to  allow  such  develop- 
ment. It  was  indicated  that  growth  to- 
ward improved  quality  would  have  to 
begin  from  the  present  broadcast  stand- 
ards of  525-line,  black-and-white.  Chan- 
nels 50  megacycles  wide,  it  was  esti- 
mated, would  be  needed  to  give  the 
necessary  high  quabty  of  picture  in 
b-and-w  and  also  subsequently  in  full 
color. 

As  many  as  60  different  channels  might 
be  needed  for  a  complete  and  thoroughly 


competitive  nation-wide  theatre  Tv  sys- 
tem. In  any  given  locality,  fewer  chan- 
nels might  provide  adequate  service. 

Means  for  Distributing  Programs 

A  prime  interest  of  the  FCC  was 
whether  common  carriers  could  handle 
the  distribution  of  theatre  Tv  programs, 
leaving  the  air  waves  available  for  broad- 
cast and  other  services.  The  SMPE  re- 
plied that  the  common  carriers  could  not 
now  transmit  the  quality  of  picture 
needed,  nor  do  they  have  sufficient  cable 
facilities  available  to  deliver  any  kind 
of  picture  extensively.  In  fact,  such 
facilities  are  so  limited  at  the  present 
time  that  the  present  broadcast  networks 
are  forced  to  work  out  a  channel-sharing 
schedule  for  inter-city  distribution  of 
programs. 

The  SMPE  feels  that  a  coaxial  cable 
might  not  be  able  to  deliver  necessary 
picture  quality  even  after  several  years 
of  additional  research,  and  therefore  told 
the  FCC  that  radio  frequencies  would  be 
needed  regardless  of  whether  the  motion 
picture  industry  distributed  its  own  pro- 
grams or  they  were  carried  from  point 
to  point  by  the  telephone  company. 

This  was  the  third  time  in  five  years 
that  the  SMPE  filed  statements  with  the 
FCC  favoring  the  allocation  of  frequency 
bands  for  theatre  Tv.  In  1944  and  again 
in  1947  the  SMPE  asked  for  specific 
allocations,  and  certain  channels  were 
set  aside  each  time  for  experimental  use. 
The  present  question  is  one  of  commer- 
cial use,  and  the  FCC's  decision  may  well 
decide  the  fate  of  theatre  Tv. 

Tight  SMPE-Theatre  Accord 

Conferences  have  been  held  recently 
by  the  SMPE  with  Theatre  Owners  of 
America,  the  Motion  Picture  Association, 
and  several  other  industry  groups  in  an 
attempt  to  provide  a  well-rounded  picture 
of  what  theatre  Tv  means  technically. 
When  asked  about  programming  and  the 
economics  of  such  a  service,  the  Engi- 
neers bowed  out,  saying  that  those  were 
questions  which  ultimate  users  of  theatre 
television  would  be  required  to  answer 
for  themselves. 

To  help  them  find  these  answers,  sev- 
eral important  factors  were  presented  by 
the  SMPE  to  the  FCC.  Among  the  things 
which  must  be  considered  are:  the  qual- 


ity of  the  picture  required;  the  avail- 
ability of  circuits  which  would  allow 
rapid  service  to  his  own  or  other  thea- 
tres; the  number  of  channels  needed  to 
pick  up  and  distribute  programs;  the 
availability  of  equipment  for  expanded 
service  and  the  construction  and  main- 
tenance costs  of  installations  as  well  as 
of  distribution   facilities. 

Industry  trade  groups,  including  TOA 
and  MPA  have  stated  publicly  that  they 
will  support  the  position  of  the  SMPE 
and  will  also  ask  the  FCC  to  hold  a 
public  hearing  where  all  united  and  di- 
verse interests  may  be  heard. 


RCA  Electronic  Color  System 

RCA's  announcement  of  a  new  system 
of  transmitting  Tv  in  full  color,  which 
eliminates  virtually  all  of  the  major  tech- 
nical and  economic  problems  that  have 
delayed  a  changeover  from  the  present 
black-and-white  pictures,  put  other 
broadcasters  in  a  dither  and  occasioned 
no  bttle  concern  among  set  dealers  who 
foresaw  a  sharp  decline  in  sales. 

Under  the  RCA  all-electronic  system, 
as  opposed  to  the  CBS  mechanical  set-up, 
no  changes  are  required  in  present  trans- 
mission standards  and  home  receivers 
now  in  operation  will  have  continued 
usefulness.  Existing  receivers  will  need 
neither  modification  nor  additional  equip- 
ment to  continue  to  receive  b-and-w  pic- 
tures from  stations  transmitting  in  color. 
Addition  of  an  adapter,  reported  to  cost 
$75  at  retail,  would  enable  such  sets  to 
pick  up  images  in  color.  New  sets,  in 
turn,  would  be  able  to  receive  programs 
in  both  color  and  b-and-w. 

With  all  types  of  sets  assured  of  con- 
tinuing service,  RCA  said,  both  b-and-w 
and  color  stations  could  survive  the  tran- 
sitional period  in  Tv  without  loss  of  audi- 
ence. How  to  turn  this  trick  without 
making  obsolete  the  broadcasting  and 
receiving  equipment  now  being  used  has 
been  a  source  of  sharp  controversy  in 
the  Tv  industry  for  many  years. 

How  the  RCA  Color  System  Works 

In  technical  terms,  the  RCA  unit  uses 
three  separate  signals  for  the  primary 
colors  of  Tv — green,  blue  and  red — 
which  are  sampled  electronically  and 
then  combined  into  one  over-all  signal 
which  is  transmitted.  At  the  receiver  the 
(Continued  on  page  27) 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


15 


New  Series 
of  Lenses 
for  16-mm 
Professional 
Projection 


A.     E.     NEUMER 

Bausch  &  Lomb  Optical  Company 

Here  is  the  low-down  covering  the  mounting, 
optical  performance,  and  optical  design  of 
a  new  series  of  16-mm  projection  lenses  for 
professional  use.  Focal  lengths  of  2  to  4 
inches,  in  half-inch  steps,  with  speeds  of 
F:1.6  are  provided.  Measurements  of  resolv- 
ing power,  optical  corrections,  and  vignet- 
ting are  included. 


THE  lenses  currently  used  in  prac- 
tically all  16-mm  projectors  tradi- 
tionally have  been  of  the  Petzval 
type,  designed  originally  by  Joseph  Petz- 
val in  Vienna  around  1840  primarily  as 
a  portrait  lens.  The  basic  design  has 
remained  the  same,  although  numerous 
detailed  changes  and  improvements  have 
been  made  over  the  years. 

Essentially  it  consists  of  two  sets  of 
lenses,  each  set  separately  achromatized 
and  with  a  comparatively  large  separa- 
tion betwen  them.  The  front  half  is 
usually  cemented,  while  the  rear  lenses 
are  separated  by  a  small  air  space  as 
shown  in  Fig.  1. 

The  basic  form  was  notably  improved 
by  Dallmeyer,  who  in  1866  reconstructed 
the  back  combination  by  reversing  the 
elements  and  changing  their  shape.  Fur- 
ther changes  have  been  made  by  unce- 
menting  the  front  combination,  thereby 
giving  an  extra  degree  of  freedom  in 
the  design.  This  step  has  the  obvious 
disadvantage,  however,  of  adding  two 
extra  air-glass  surfaces  which  tend  to 
reduce  the  over-all  transmission  and  con- 
trast in  the  image. 

The  Petzval  construction  readily  lends 
itself  to  lenses  of  very  large  aperture 
ratios  with  excellent  center  definition, 
but  the  covering  power  is  seriously 
limited  by  heavy  curvature  of  field  which 


becomes  noticeable  a  few  degrees  off  the" 
lens  axis.  Many  attempts  have  been 
made  to  flatten  this  field  both  artificially, 
in  the  parlance  of  the  lens  designer,  by 
introducing  large  amounts  of  astigma- 
tism, or  by  adding  a  field-flattening  ele- 
ment close  to  the  film  plane. 

In  spite  of  all  these  efforts,  a  good 
state  of  correction  of  the  field  aberra- 
tions has  never  been  achieved.  Never- 
theless, considering  the  factors  which  in 
the  past  have  motivated  16-mm  projector 
design,  the  choice  of  the  Petzval  lens 
was  seemingly  justified  in  that  speed 
and  cost  were  factors  of  more  importance 
than  screen  definition. 

Because  of  the  limitations  imposed  by 
the  Petzval  design,  mainly  on  resolving 
power,  and  because  of  the  demand  for 
a  better  lens,  about  15  years  ago  de- 
signers abandoned  it  for  35-mm  projec- 
tion in  favor  of  an  anastigmat  design. 
"Anastigmat,"  as  used  here,  means  a 
lens  corrected  simultaneously  for  astig- 
matism and  curvature  of  field  and,  at 
the  same  time,  being  fully  color-cor- 
rected. The  latter  requirement  is  equally 
important  for  black-and-white  as  well  as 
color  film. 

Basic  Form  of  New  Series 

Such  lenses  were  in  rather  common 
use  in  photography  but  were  of  rela- 
tively low  speed,  therefore,  it  was  ap- 
parent at  the  outset  that  a  more  com- 
plicated and  therefore  more  expensive 
lens  form  would  have  to  be  developed. 

As  far  back  as  1921,  Lee  in  England 
had  succeeded  in  developing  a  6-element 
anastigmat  type  which  worked  reason- 
ably well  at  an  aperture  of  F:2.  This 
lens,  which  can  be  traced  all  the  way 
back  to  the  original  Gauss  telescope  ob- 
jective, consists  of  two  single  outside 
elements  with  two  cemented  doublets  in 
between.  This  basic  design  formed  the 
background  for  the  F:2.3  Baltar  and 
later  the  F:2  Super  Cinephor. 

Because  of  the  unusual  success  of 
these  lenses,  and  after  a  careful  survey 
of  other  possible  approaches,  it  was  de- 
cided to  use  the  same  basic  form  for  the 
Super  Cinephor  16,  in  focal  lengths 
from  2  to  4  inches  in  steps  of  %  inch, 
all  rated  at  F:1.6    (see  Figs.  2  and  3). 

Light  Source  Requisites  for  16-mm 

One  of  the  big  differences  between 
16-  and  35-mm  projectors  is  in  the  in- 
herent need  for  faster  lenses  in  order  to 
achieve     sufficient     screen     illumination. 


The  main  reason  for  this  is  that  because 
ofrthe  desire  to  make  most  16-mm  equip- 
ment portable,  the  use  of  carbon  arcs 
with  their  attendant  power  supply  is  not 
feasible.  The  only  alternative  is  to  use 
a  tungsten  filament  or,  as  has  more  re- 
cently been  suggested,  a  concentrated 
arc. 

However,  the  inherent  brightness  per 
unit  area  of  a  projection-type  tungsten 
filament  is  something  of  the  order  of  1/7 
that  of  a  low-intensity  carbon,  and  about 
1/30  that  of  a  high-intensity  carbon. 
Similarly,  the  concentrated  arc  has  an 
inherent  brightness  per  unit  area  about 
1/1.75  that  of  low-intensity  carbons  and 
1/8  that  of  high-intensity  carbons. 

Furthermore,  even  if  carbon  arcs  are 
used  in  the  16-mm  projector,  since  the 
magnification  is  usually  much  greater 
than  with  35-mm,  the  brightness  per 
unit  area  of  the  screen  will  be  much  less. 

Fast  Lens  is  Imperative 

The  result  of  these  factors  is  that  for 
16-mm  projection  a  fast  lens  is  impera- 
tive. To  the  lens  designer  this  imposes 
a  most  formidable  problem  since  aberra- 
tions increase  rapidly  with  lens  speed. 

Spherical  aberration,  for  example,  in- 
creases as  the  square  of  the  aperture. 
Thus,  an  F:1.6  lens  identical  to  and  of 
the  same  focal  length  as  an  F:2  lens 
would  have  more  than  twice  the  spherical 
aberration.  Furthermore,  since  image 
detail  on  the  16-mm  frame  is  smaller 
than  on  the  35-mm  frame,  the  16-mm 
projection  lens  should  be  capable  of  re- 
solving powers  considerably  in  excess 
of  its  big  brother  if  it  is  expected  to  do 
the  same  type  of  job. 

Considering  all  these  factors,  the  de- 
sign of  the  Super  Cinephor  16  was  not 
easy.  It  was  completed  only  after  about 
two  years  of  painstaking  effort  and  was 
greatly  abetted  by  the  use  of  new  dense 
barium  crown  glasses  which  up  to  the 
present  have  not  been  generally  avail- 
able. 

Tests  Exceed  Fondest  Hopes 

Each  focal  length  in  the  series  was 
designed  individually,  but  they  are  all 
of  the  same  basic  form.  The  final  re- 
sults on  paper  looked  extremely  promis- 
ing, but  frequently  it  happens  that  a 
particular  pattern  of  aberrations  which 
looks  well  according  to  computations  will 
add  up  to  yield  a  poor  actual  result. 
Therefore,  final  specifications  were  not 
released    until    sample    lenses    of    each 


FRONT 


FIGURE  1 

Typical  projection  objective  of 

the  Petzval  type. 


tJ.   Soc.  Mot.  Pict.   Eng.,  May  1949. 


BACK 


FILM 


16 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


focal  length  were  made  and  thoroughly 
tested. 

The  results  of  these  tests  exceeded 
our  fondest  hopes.  For  example,  the 
2-inch  lens,  which  can  be  considered  as 
the  standard  focal  length,  at  full  aper- 
ture has  a  measured  spherical  aberration 
of  about  0.1%  of  the  focal  length,  or 
50  microns.  At  the  extreme  corner  of 
the  16-mm  frame  there  is  no  measurable 
astigmatism,  but  approximately  0.2%,  or 
100  microns,  inward  curvature  of  field. 

A  more  understandable  picture  of 
what  these  corrections  mean  can  be  ob- 
tained from  the  fact  that  any  lens  of 
the  series  will  resolve  visually  more  than 
90  lines  per  mm  anywhere  in  the  16-mm 
frame.  This  is  not  only  about  double 
what  the  average  Petzval  lens  will  re- 
solve in  the  corners  of  the  frame,  but  in 
addition  the  quality  of  resolution,  which 
is  the  one  hidden  factor  in  any  statement 
of  resolving  power,  is  excellent. 

While  the  Super  Cinephor  16  is  classi- 
fied as  a  projection  lens,  actually,  in 
every  respect,  it  is  a  high-quality  photo- 
graphic lens. 

No  lens  is  any  better  than  it  is 
mounted,  and  for  that  reason  a  consider- 
able amount  of  thought  was  given  to 
the  case,  keeping  in  mind  the  particular 
application.  We  have  experimented  and 
actually  used  for  some  time  a  one-piece 
barrel  type  of  mount  the  inside  of  which 
is  a  true  hollow  cylinder.  The  lens  com- 
ponents are  individually  mounted  into 
cells  which  are  accurately  turned  to  fit 
the  inside  diameter  of  the  barrel. 

Various  Precise  Assembly  Steps 

Assembly  is  accomplished  by  stacking 
the  cells  inside  the  barrel  with  the  addi- 
tion of  spacer  rings,  plus  the  addition 
of  a  threaded  retainer  at  one  end  to  com- 
plete the  job  (Fig.  4) .  This  method  has 
been  quite  successful,  but  it  does  not 
eliminate  some  of  the  troubles  which 
have  always  been  a  problem  in  lens- 
mounting. 

First  of  all,  the  lens  cells  must  be 
accurately  turned  to  fit  the  barrel  with 
no  more  than  about  0.001  inch  clearance. 
Second,  the  degree  of  centering  possible 
depends  on  how  accurately  the  lens  ele- 
ments can  be  edged  and  how  well  they 
can  be  fitted  to  their  respective  cells. 


FIGURE  4 
Exploded  view  showing  the  optics  and  spacer  rings. 


In  actual  manufacture,  edging  is  a 
difficult  operation,  particularly  on  weak 
lenses,  with  the  result  that  the  finished 
diameter  of  a  lens  is  not  always  con- 
centric with  its  axis  (the  axis  being  the 
line  through  the  centers  of  curvature  of 
the  two  surfaces).  All  these  sources  of 
error  frequently  build  up  causing  ob- 
jectionable decentering  and  therefore 
rejection. 

An  entirely  new  technique  has  been 
developed  in  which  the  lenses  are  not 
centered  by  means  of  their  edged  diam- 
eter. Instead,  spacer  rings  which  are 
turned  to  fit  the  bore  of  the  barrel  con- 
tact the  lens  surfaces  near  the  periphery. 
The  elements  are  actually  edged  to  a 
smaller  diameter  than  the  bore  and  are 
therefore  free  to  seek  their  own  center 
between  any  two  spacer  rings. 

In  other  words,  centering  is  effected 
by  means  of  the  differential  thickness  of 
the  lenses  and  obviously  eliminates  the 
need  for  accurate  edging  as  well  as  the 
expensive  operation  of  fitting  the  ele- 
ments to  individual  cells.  When  the 
spacer  rings  are  designed  correctly,  this 
method  has  proved  highly  successful 
(Fig.  4) . 

Weight,  External  Dimensions 

Because  of  the  weight  factor,  all  metal 
parts  are  made  of  aluminum  with  a  dull 
black  anodized  finish  inside  and  a  satin 
anodized  finish  outside.    This  eliminates 


FIG.  2.    Super  Cinephor  16. 


3.    Cross-section  showing  the  mounting  details 
of  the  4-inch  Cinephor  16. 


the  necessity  of  using  any  lacquer  inside 
the  mount  and  avoids  the  trouble  en- 
countered with  lacquer  eventually  flaking 
oft  and  sticking  to  the  inner  surfaces  of 
the  lens  elements.  Finally,  the  lenses  are 
sealed  at  both  ends  against  dust  and 
moisture. 

The  external  dimensions  of  all  the  lens 
mounts  have  been  made  in  accordance 
with  ASA  standard  Z52.1-1944.  The 
diameter  of  the  mounting  section  which 
fits  into  the  projector  is  2.062  inches. 
In  addition,  the  2-inch  lens  is  being  of- 
fered in  the  semi-standard  1  3/16-inch 
diameter,  rolled-thread  focusing  type  of 
mount  which  has  long  been  used  on  both 
8-  and  16-mm  projectors.  Because  of 
size  limitations,  it  is  not  possible  to  fit 
any  of  the  longer  focal  lengths  in  this 
style  of  mounting  without  reducing  the 
speed. 

Maximum  Screen  Light  Obtained 

As  regards  screen  illumination  with 
these  lenses,  every  effort  has  been  made 
to  take  full  advantage  of  the  F:1.6  speed. 
All  air-glass  surfaces  are  "Balcoted." 
However,  so  far  as  illumination  is  con- 
cerned, any  lens  is  no  better  than  the 
condenser  and  the  light  source  behind  it. 

In  the  absence  of  no  other  interference 
in  the  projection  train,  it  is  the  com- 
bination of  these  three  elements  which 
determines  the  total  amount  of  lumens 
reaching  the  screen,  and  also  the  degree 
of  uniformity  of  illumination  from  the 
center  to  the  edge  of  the  screen.  While 
it  is  not  the  main  purpose  herein  to 
describe  condensing  systems,  a  few  words 
concerning  them  is  in  order. 

Based  on  the  published  brightness 
values  of  a  750-watt,  25-hour  tungsten 
projection  filament,  it  has  been  computed 
that  with  a  coated  F:1.6  projection  lens 
of  the  Super  Cinephor  16  type,  a  perfect 
condenser,  a  mirror  behind  the  lamp, 
(Continued  on  page  28) 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


17 


IN  THE 


SPOTLIGHT 


By 

HARRY 

SHERMAN 


A  PRETTY  sad  condition  prevails  in 
many  of  our  Local  Unions.  When 
members  are  taken  ill  and  are  unable  to 
work,  or  are  in  financial  straits,  it  is 
often  necessary  for  the  membership  to 
pass  the  hat,  so  to  speak,  to  aid  the  un- 
fortunate member.  Many  of  our  more 
progressive  Locals — notably  New  York 
Local  306  and  Chicago  Local  110 — have 
pension  funds,  sick  and  death  benefits, 
and  other  plans  for  helping  needy  mem- 
bers. These  men  are  assisted  during  a 
period  of  stress  without  loss  of  human 
dignity  and  with  a  feeling  of  hope  for 
the  future.  It  should  not  be  necessary 
to  kill  a  man's  self-respect  while  lending 
a  helping  hand,  which  so  often  happens 
when  donations  are  made  to  carry  him 
over  a  painful  period. 

•  For  having  loyally  served  his  local 
for  ny2  years,  Milton  E.  Franklin,  for- 
mer business  agent  for  Local  577,  San 
Bernardino,  Calif.,  was  awarded  a  gold 
life  membership  card.  About  25  out-of- 
town  IA  men  working  out  of  the  San 
Bernardino  Local  presented  him  with  a 
beautiful  diamond,  mounted  in  the  center 
of  the  engraved  gold  card. 

•  Robert  G.  W.  Bennett  is  the  new  busi- 
ness agent  for  San  Bernardino  Local  577, 
succeeding  Milton  E.  Franklin,  who  re- 
tired because  of  ill  health. 

•  The  Frenchy  Biencourts  of  San  An- 
tonio, Texas,  are  celebrating  the  advent  of 
a  new  member  to  their  household — a  son. 
Frenchy,  business  manager  of  Local  76 
for  a  number  of  years,  seems  to  be  bear- 
ing up  pretty  well  under  the  strain. 

•  Although  the  Provincial  authorities 
decided  against  Canadian  Locals  302 
(Calgary)  and  371  (Edmonton)  in  their 
fight  to  maintain  the  two-men  projection 
shift,  the  matter  is  far  from  closed  as  far 
as  these  Locals  are  concerned.  They  are 
determined  to  continue  the  fight  to  regain 
the  conditions  that  they  voluntarily  gave 
up  during  the  wartime  manpower  short- 
age. Then,  in  order  to  keep  the  theatres 
open  and  operating,  they  agreed  to  a 
one-man  projection  shift,  but  only  for  the 
duration  of  the  war.  When  the  war  ended, 


however,  the  Alberta  Theatres  Associa- 
tion showed  its  appreciation  of  the 
Unions'  cooperation  by  appealing  to  the 
Provincial  authorities  for  a  permanent 
one-man  projection  shift.  The  decision 
rendered  by  the  Special  Advisory  Board 
is  the  result  of  a  report  submitted  by  its 
chairman,  Hon.  Mr.  Justice  C.  C.  Mc- 
Laurin. 

•  Arthur  Hamilton,  65,  member  of  Bos- 
ton Local  182,  died  several  weeks  ago 
while  visiting  his  son,  Ed,  in  Port  Huron, 
Mich.  Arthur  was  president  of  the  Local 
back  in  1919.  Funeral  services  were  held 
at  Union,  N.  H.,  where  he  made  his  home 
during  the  past  years. 

•  George  F.  Mills,  old-time  member  of 
Local  223,  Providence,  R.  I.,  was  taken 
ill  recently  and  is  recuperating  at  the 
Wallum  Lake  Sanitorium  at  Wallum 
Lake,  R.  I.  He  would  like  very  much  to 
hear  from  his  many  friends  in  the  Alli- 
ance ;  a  note  or  a  card  would  help  greatly 
to  cheer  him  up.   How  about  it,  boys? 

•  The  annual  meeting  of  the  Wisconsin 
Association  of  Stage  Employes  and  Pro- 
jectionists was  held  at  Eau  Claire,  Wis., 

HONOR  VETERAN  CALIFORNIA  IA  MAN 


George  Schaffer  (right),  of  Los  Angeles  Local 
150,  chats  with  Howard  Neece  (left)  and  Joe 
Godfrey  (center),  business  agent  and  president, 
respectively,  of  Local  709,  Ventura,  Calif.  The 
Ventura  Local  tendered  Schaffer  a  gold  honor- 
ary life  membership  card  for  his  many  services 
to  Southern  California  Locals.  Present  were 
Local  709  membership;  Fred  Loakes  and  Clar- 
ence Albecker,  Local  150;  Orin  Johnston,  Local 
281,  Paducah,  Ky.,  and  Walter  Jeffries,  Local 
457,  Superior,  Wis. 


on  August  15,  in  conjunction  with  the 
Wisconsin  State  Federation  of  Labor 
meeting.  The  Taft-Hartley  Law  came  in 
for  considerable  discussion,  with  talks 
on  the  topic  being  given  by  Thomas  Shea, 
assistant  IA  president;  Felix  Snow,  IA 
6th  vice-president,  and  Wm.  Donnelly, 
IA  representative. 

Officers  elected  for  the  ensuing  year 
are  John  Kunstman  (Sheboygan  Local 
655),  president;  Glenn  C.  Kalkhoff  (Mil- 
waukee Local  164),  vice-president;  Wil- 
liam Rieder  (Fond  du  Lac  Local  235), 
secretary,  and  Stanley  Przlomski  (Keno- 
sha Local  361 ) ,  treasurer.  Oscar  E.  Olson, 
Milwaukee  Local  164,  was  elected  to  rep- 
resent the  State  Association  on  the  9th 
District  IA  advisory  board. 

A  large  delegation  from  Chicago  Lo- 
cal 110,  headed  by  Gene  Atkinson,  busi- 
ness manager;  James  Gorman,  president, 
and  Clarence  Jalas,  treasurer,  attended 
the  meeting.  At  the  close  of  the  business 
session  the  delegates  were  the  guests  of 
Eau  Claire  Local  475  at  a  delicious 
luncheon. 

•  Leo  Weiss,  charter  member  and  for- 
mer secretary  of  Cleveland  Local  160. 
was  fatally  stricken  with .  a  heart  attack 
while  on  his  way  to  the  Stillman  Theatre, 
where  he  had  been  employed  as  pro- 
jectionist for  about  20  years.  He  is  sur- 
vived by  his  wife. 

•  One  of  the  highlights  of  the  new  bowl- 
ing season  (September  1949 — May  1950) 
will  be  a  return  match  game  between  the 
One-Sixty  League  of  Cleveland  (Local 
160)  and  the  Nightingale  Club  of  De- 
troit (Local  199).  The  Cleveland  team 
still  is  smarting  from  the  defeat  suffered 
last  season  and  is  determined  to  bring 
back  to  its  headquarters  the  William 
(Bill)  Kramer  Trophy,  now  gracing  the 
offices  of  Local  199. 

Bowling  has  become  a  very  popular 
sport  with  a  number  of  IA  Locals,  with 
many  of  them  forming  their  own  clubs 
and  competing  with  other  teams.  Tom 
Fitzgerald,  member  of  the  Cleveland 
club,  has  come  up  with  a  suggestion 
which  we  pass  along.  He  suggests  that 
all  IA  bowling  teams  get  together  and 


18 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


line  up  a  series  of  match  games  between 
the  various  Locals,  with  the  best  teams 
competing  for  a  national  trophy  at  a 
bowling  tournament  to  be  held  every 
two  years  at  IA  conventions.  To  this  end, 
IP  will  be  very  glad  to  donate  the  na- 
tional trophy,   suitably  inscribed. 

We  should  bke  to  get  the  reaction  from 
the  Milwaukee,  Chicago,  Pittsburgh,  Los 
Angeles,  Youngstown,  Cincinnati  and 
other  IA  bowling  clubs  to  the  foregoing. 

•  By  a  vote  of  54  to  51,  Local  244,  New- 
ark, N.  J.,  which  has  been  under  the 
supervision  of  the  IA  General  Office  for 
the  past  four  years,  will  remain  under 
International  control.  The  election  was 
authorized  by  the  General  Executive 
Board  at  the  mid-summer  meeting  held 
in  Denver,  Colo.,  and  was  personally  con- 
ducted by  President  Walsh. 

The  members  were  offered  the  alterna- 
tive of  Local  autonomy  provided  they 
agreed  to  the  following  proposals: 

1.  All  meetings  to  be  peacefully  and 
properly  conducted. 

2.  All  cliques,  groups  and  clubs  be  im- 
mediately dissolved  and  none  re- 
sumed or  organized. 

3.  Voting  machines  to  be  used  in  all 
elections. 

4.  All  International  laws  be  complied 
with. 

5.  Louis  Kaufman,  former  business 
agent,  be  barred  from  holding  any 
office  for  at  least  five  years. 

6.  Compliance  with  the  Local's  seniority 
laws. 

7.  No  "permit,"  "apprentice,"  "junior," 
or  "application"  membership  system 
be  maintained  in  violation  of  the  IA's 
Constitution  and  By-Laws. 

8.  Membership  dues  be  reduced  from 
|180  to  $60  per  year,  plus  a  2%  as- 
sessment on  gross  earnings  per  year. 

Under  the  emergency  powers  granted 
the  International  president,  the  IA  took 
over  control  of  Local,  244  in  September, 
1945,  after  several  meetings  had  broken 
up  in  fist  fights  and  a  majority  of  the 
members  had  petitioned  President  Walsh 
to  step  in.  Since  then  the  Local  has  been 
under  the  supervision  of  Thomas  V. 
Green,  IA  representative,  appointed  by 
Walsh. 

•  Mike  Mungovan,  business  agent  of 
Local  25,  Rochester.  N.  Y.,  did  it  again. 
He  recently  negotiated  new  contracts 
calling  for  an  8%  increase.  Mike  is  al- 
ways on  the  beam,  pitching  for  his  men. 

•  We  were  shocked  to  hear  of  the  sud- 
den death  of  our  very  good  friend,  Ben 
Brown,  charter  member  and  former 
president  of  Cleveland  Local  160  and, 
later,  member  of  Pittsburgh  Local  171. 
Ben  was  one  of  the  old-timers  in  the  Alli- 
ance, having  been  an  IA  representative 
during  the  Canavan  administration.  For 


many  years  he  was  the  chief  projection- 
ist for  Warners  in  Pittsburgh,  retiring 
from  that  post  to  devote  his  entire  time 
to  a  theatre  he  acquired  in  Connellsville, 
Penna.  He  is  survived  by  his  wife,  Rose; 
a  son,  Edwin,  and  a  daughter,  Shirley. 

•  One  of  our  overseas  subscribers,  name- 
less here  for  obvious  reasons,  sent  us  a 
clipping  from  the  London  Daily  Express 
in  which  Tom  O'Brien,  head  of  the  Brit- 
ish NATKE,  was  raked  over  the  coals  for 
his  violent  tirade  against  the  United 
States.  The  Express  accused  O'Brien  of 
"fishwife  hysteria"  and  recommended 
that  "he  be  repudiated  by  the  delegates 
to  the  forthcoming  Trades  Union  Con- 
gress .  .  .  and  that  the  Nottingham  elec- 
tors should  reject  him  at  the  next  Gen- 
eral Election."  What  happened  to  the 
erstwhile    genial    Mr.    O'Brien? 

•  Robert  E.  Shuff,  son  of  John  Shuff, 
business  agent  of  Local  364,  Akron,  Ohio, 
has  opened  his  own  law  offices  at  1306 
First  National  Tower  Bldg.,  Akron,  Ohio. 
He  was  formerly  on  the  staff  of  the 
NLRB  and  was  for  five  years  assistant 
general  counsel  for  the  United  Rubber 
Workers  of  America.  We  extend  our  best 
wishes  to  young  Shuff  for  a  most  success- 
ful career. 

•  Latest  addition  to  the  ranks  of  IA 
journalists  is  Clyde  Cooley,  secretary  of 
Locals  343,  Omaha,  Nebr.,  and  336, 
Council  Bluffs,  Iowa,  who  now  writes  a 
weekly  column  for  The  Unionist,  a  Labor 
weekly  published  in  Omaha.  Clyde's  first 
column  evoked  memories  of  our  younger 
days  because  it  paid  a  much  deserved 
tribute  to  Abe  Blank,  president  of  Tri- 
States  Theatres.   One  memory  of  Blank 

BOSTON  LOCAL  182  HONORS  PRESIDENT 


In  appreciation  of  services  rendered  Local  182 
for  the  past  26  years,  Joseph  Nuzzolo,  Sr., 
president,  was  recently  presented  with  a  gold 
life  membership  card.  Shown  here  after  the 
presentation  ceremonies  are,  bottom  row,  left  to 
right:  Nuzzolo,  Morris  A.  Goldman  (vice-presi- 
dent), and  Myer  Bixgorne.  Rear,  Samuel  Gar- 
finkle,  Walter  F.  Diehl  (business  representative), 
Charles  Jandreau,  Maurice  Synder,  and  Joseph 
Caplan  (treasurer). 


persists:  although  he  engaged  in  many 
a  stiff  tussle  with  IA  Locals  in  his  terri- 
tory, all  disputes  were  settled  amicably 
without  resort  to  a  strike. 

•  Recent  out-of-town  visitors  to  the  offi- 
ces of  IP:  From  Boston  Local  182  came 
Joe  Nuzzolo,  president;  Walter  Diehl, 
business  agent;  Leon  Narbut,  financial- 
secretary,  and  Harold  Kaitz,  member  of 
the  executive  board.  Canadian  callers 
were  Fred  Hoffman,  Montreal  Local  262; 
Wm.  McCaul  and  Gus  Demery,  Toronto 
Local  173,  and  C.  Dentelbeck,  Jr.,  Local 
461,  St.  Catherines,  Ont. ;  from  Syracuse, 
N.  Y.,  came  George  F.  Raaflaub,  secre- 
tary of  Local  376. 

25  Years  Ago — September  1924 

•  John  0.  Benner,  secretary  of  District 
No.  8,  issued  a  call  to  member  Locals 
to  submit  copies  of  their  wage  scales  and 
working  agreements.  He  announced  that 
the  office  of  District  secretary  was  ready 
to  take  care  of  all  matters  brought  to  its 
attention.  .  .  .  The  controversy  between 
the  Hippodrome  Theatre  in  Taft,  Calif., 
and  Local  518  over  the  use  of  remote 
controls  was  satisfactorily  adjusted  by 
Cleve  Beck,  IA  5th  vice-president.  .  .  . 
Guy  Culver,  IA  4th  vice-president,  re- 
jected the  application  for  a  charter  at 
Pitcher,  Okla.  .  .  .  Due  to  the  efforts  of 
Charlie  Crickmore,  IA  representative, 
the  Grand  Theatre  in  Aberdeen.  Wash, 
agreed  to  operate  under  union  conditions 
satisfactory  to  Aberdeen  Local  429.  .  .  . 
Representative  Bill  Dillon  recommended 
that  the  General  Office  grant  the  plea  of 
Haverhill,  Mass.  Local  397  for  financial 
assistance.  .  .  .  Difficulties  developing  in 
the  ranks  of  Local  637.  Kingston.  N.  Y. 
were  reported  amicably  settled  by  Harry 
Sherman,  IA  representative.  .  .  .  Local 
321,  Tampa,  Fla.  inserted  a  notice  in  the 
IA  Bulletin  requesting  members  of  out- 
side affiliated  Locals  not  to  come  to 
Tampa  seeking  work,  as  many  of  its  own 
members  were  unemployed  due  to  a 
business  slump  in  that  city.  .  .  .  Road  call 
against  the  Brandies  Theatre  in  Omaha. 
Nebr.  discontinued.  .  .  .  New  England 
District  No.  3  held  its  annual  outing  at 
Warwick.  R.  I.  Features  of  the  outing 
were  the  baseball  games  between  Provi- 
dence Locals  23  and  223.  won  by  the 
latter,  and  Boston  Local  11  vs.  Pittsfield 
Local  275,  with  Pittsfield  the  victor.  The 
games  were  umpired  by  Harry  Sherman, 
assisted  by  Dick  Green.  .  .  .  Bill  Lang, 
manager  of  the  General  Office  adjust- 
ment and  claim  departments,  installed 
the  charter  for  the  newly  organized 
Studio  Mechanics  Local  No.  52,  New 
York  City.  .  .  .  Local  544,  Kokomo,  Ind. 
concluded  new  agreements  calling  for  a 
$5  weekly  increase.  .  .  .  Representative 
Raoul  assisted  Local  519,  Mobile,  Ala., 
in  obtaining  signed  agreements. 


INTERNATIONAL    PROJECTIONIST 


September    1949 


19 


Cooling  Means  for  H-l  Arc  Projection 

The  candid  appraisal  in  IP  recently*  of  means  for  protecting  the  film  from  the 
harmful  effects  of  the  intense  heat  produced  by  high-intensity  carbon  arcs 
induced  a  flood  of  comment  from  the  field  relative  to  the  efficacy  of  the  various 
methods  cited.  To  satisfy  the  widespread  demand  for  further  data  anent  this 
topic,  IP  presents  this  unique  symposium  which  reflects  the  views  of  leading 
manufacturers  of  projection  equipment  on  this  most  pressing  projection  problem. 


By  CLARENCE  S.  ASHCRAFT 

President,  C.  S.  Ashcraft  Manufacturing  Co. 

TOTAL  elimination  of  destructive  heat  transmitted  or 
■  radiated  to  the  film  without  light  loss  is  a  problem  which 
has  challenged  the  ingenuity  of  the  most  experienced  arc 
lamp  people  in  the  industry.  The  fact  that  a  plurality  of 
methods  has  been  the  basis  of  experimentation  by  lamp 
manufacturers  is  at  once  an  indication  of  the  seriousness 
with  which  they  regard  this  problem  and  a  good  omen 
of  their  determination  to  solve  it. 

To  eliminate  the  effects  of  destructive  heat  on  the  film 
there  seems  to  be  only  one  solution  at  the  present  time, 
that  is,  the  interposing  of  heat-absorbing  glass  in  the  light 
beam.  I  realize  that  a  loss  of  light  accompanies  this,  but  it 
seems  that  new  glass  of  higher  light-transmission  value  is 
being  developed,  and  it  may  be  that  in  the  near  future  a 
much  higher  percentage  of  heat  may  be  removed  from  the 
light  with  much  less  loss  of  light.  Even  at  the  present  time 
with  the  extremely  high  brilliancy  obtained  by  the  new 
high-powered,  rotating-carbon,  reflector  arc,  the  light  loss 
occasioned  by  the  use  of  heat-absorbing  glass  is  more  than 
offset  by  the  increased  illumination  obtained  from  the  lamp. 

The  high  efficiency  of  this  new  type  of  lamp  is  directly 
attributable  to  the  water-cooling  of  the  positive  carbon, 
permitting  higher  current  densities  to  be  used  and  result- 
ing in  higher  intrinsic  crater  brilliancy,  and  to  the  greatly 
improved  optical  system  employed. 

Methods  for  cooling  the  projection  machine  itself  and 
protection  for  the  working  parts  of  the  projector  must  be 
left  to  the  projector  manufacturers.  This  seems  to  have 
been  accomplished  efficiently  by  those  manufacturers  using 
water-cooling  of  the  aperture  or  heat  shield.  I  can  only 
speak  as  a  lamp  manufacturer. 

Four  Distinct  Advantages  of  Carbon  Cooling 

There  seems  to  be  some  misunderstanding  as  to  the  bene- 
fits of  water-cooling  the  crater  end  of  the  carbon  and  brush 
assembly  of  a  projection  lamp.  I  do  not  believe  that  any 
responsible  lamp  manufacturer  would  claim  that  the  cool- 
ing of  the  carbon,  in  itself  and  without  increased  current, 
enhances  the  brilliancy  of  the  crater.  There  are,  however, 
four  distinct  advantages  in  water-cooling  of  the  carbon  and 
brush  assembly  which,  I  think,  cannot  be  disputed: 

(1)  Increased  arc  steadiness.  This  is  of  the  utmost  im- 
portance in  the  higher  current  ranges.  There  is  no  flicker 
and  a  distinct  reduction  in  the  erratic  flame  of  the  non- 


*  "Monthly  Chat,"  IP  for  July  1949,  p.  3. 


cooled  arc.    This,  of  course,  results  in  uniformity  of  car- 
bon consumption  and  in  screen  light  steadiness. 

(2)  Reduction  in  crater  depth.  Without  water-cooling, 
at  currents  above  the  normal  rating  of  the  carbon  the 
crater  becomes  so  deep  that  the  efficiency  of  the  arc  is 
impaired.  Water-cooling  definitely  reduces  the  crater  depth 
so  that  higher  current  densities  may  be  used  with  a  normal 
and  efficient  depth  of  crater. 

(3)  Reduction  in  carbon  consumption.  It  seems  to  be 
a  fact  that  water-cooling  does  reduce  carbon  consumption 
to  a  certain  extent.  This  is  of  importance  when  higher 
than  normal  current  densities  are  used  in  the  carbon,  for 
obvious  reasons  of  economy. 

(4)  Last,  but  by  no  means  of  least  importance,  water- 
cooling  almost  completely  eliminates  the  heat  factor  in 
those  parts  of  the  arc  lamp  adjacent  the  crater  area.  For 
the  first  time  it  is  now  possible  to  produce  high-intensity 
projection  lamps  with  carbon  contacts  which  need  never 
be  removed  for  cleaning;  in  fact,  the  longer  they  are  left 
without  cleaning  the  better  become  the  contact  surfaces. 
This  alone  is  such  a  definite  improvement  over  the  non- 
water-cooled  projection  lamp  that  it  has  been  praised  by 
every  projectionist  who  has  seen  it.  It  is  quite  a  step  for- 
ward when  the  projectionist  may  remove  the  carbon  and 
retrim  the  lamp  with  bare  hands  without  fear  of  injury. 

There  is  no  disposition  in  responsible  manufacturing 
quarters  to  minimize  either  the  seriousness  or  the  diffi- 
culty of  this  problem;  and  I  for  one  would  be  glad  to 
participate  in  a  symposium  under  the  auspices  of  the 
SMPE,  as  suggested  by  IP,  so  that  an  impartial  evaluation 
of  test  data  assembled  by  manufacturers  could  be  made. 


By  J.  ROBERT  HOFF 

Vice-President,  The  Ballantyne  Company 

FOR  the  past  nine  months  we  have  been  investigating  the 
matter  of  cooling  projection  equipment,  but,  frankly, 
the  results  obtained  to  date  have  only  served  to  point 
up  the  complexity  of  this  problem.  There  can  be  no  ques- 
tion, of  course,  as  to  the  need  for  some  cooling  means, 
as  is  attested  to  by  every  installation  using  high-amperage 
carbon  arcs. 

We  are  in  complete  accord  with  the  views  expressed 
in  your  editorial  in  the  July  issue  of  IP  to  the  effect  that 
the  cooling  of  the  lamphouse  itself,  as  a  protective  measure 
for  the  units  therein,  is  only  remotely  connected  with  the 
cooling  of  the  film  and  of  those  parts  in  the  area  of  the 
aperture.   We  would  say  that  both  the  lamphouse  and  the 


20 


INTERNATIONAL    PROJECTIONIST 


September    1949 


projector  aperture,  if  not  actually  the  film  itself,  must  be 
cooled  by  some  efficient  means. 

Dual  Aspect  of  Problem  Recognized 

We  have  obtained  rather  good  results  in  cooling  the 
lamphouse,  and  the  carbon  therein,  by  means  of  air  under 
pressure.  This  airflow  has  not  disturbed  the  steadiness  of 
the  arc,  it  prevents  pencilling  of  the  positive  carbon,  and, 
we  think,  permits  a  somewhat  larger  gas  ball  and  conse- 
quent increase  in  light.  We  realize,  of  course,  that  even 
should  complete  success  attend  our  efforts  in  effectively 
cooling  the  lamphouse,  there  still  would  remain  the  very 
acute,  and  possibly  even  more  pressing,  problem  of  re- 
ducing sharply  the  amount  of  heat  that  strikes  the  film. 

We  think  it  a  good  thing  that  this  matter  be  thrown 
open  to  full  and  frank  discussion  by  the  various  manu- 
facturers in  the  pages  of  IP,  and  we  would  certainly  wel- 
come the  opportunity  to  meet  with  representatives  of  other 
manufacturers  to  the  end  that  this  problem  might  be  licked 
for  the  benefit  of  the  entire  industry.  If  such  a  conference 
might  be  arranged,  count  us  in. 

By  LARRY  W.  DAVEE 

Sales  Manager,  Century  Projector  Corp. 

THERE  should  be  no  confusion  anent  effective  means 
I  for  cooling  carbon  arc  lamps,  projectors  and  the  film 
itself.  It  would  seem  that  we  need  to  clarify  the  thinking 
of  those  most  intimately  associated  with  the  equipment 
industry,  including  those  whose  function  it  is  to  purchase 
and  maintain  projection  equipment  in  the  theatre.  During 
the  past  few  years  new  ideas  have  been  injected  into  the 
equipment  business,  together  with  a  new  conception  of  the 
responsibilities   of  the   equipment  manufacturers. 

These  new  ideas,  these  new  conceptions  have  the  old- 
timers  confused.  We  need  now,  more  than  ever,  increased 
publicity  and  more  frequent  open  engineering  discussions 
to  make  these  new  things  as  well-known  as  the  older  ideas 
were  for  so  many  years. 

To  begin  at  the  beginning,  when  something  gets  too  hot 
we  cool  it.  When  heat  becomes  a  problem  the  most  simple 
expedient  is  to  take  it  away — a  process  which  involves 
many  sciences.  Scientific  knowledge  plus  the  many  years 
of  first-hand  experience  most  of  us  have  had  with  pro- 
jection equipment  will  lick  this  problem  of  excessive  heat. 

Basic  Scientific  Laws  Unchanged  by  Discussion 

Broadly  speaking,  there  are  three  primary  scientific 
factors  involved  in  this  problem :  mechanics,  heat  and  light, 
each  of  which  is  a  study  in  itself  and  each  having  its  own 
peculiar  characteristics.  Heat  and  light  react  under  known 
laws  which  no  amount  of  discussion  can  change.  If  these 
laws  were  better  understood  generally,  much  of  the  exist- 
ing confusion  would  disappear. 

Light  and  sound  follow  a  geometric  progression  as  to 
their  effect  on  the  eye  and  the  ear.  As  light  and  sound 
grow  in  intensity,  it  requires  increasingly  greater  incre- 
ments of  level  to  make  the  same  apparent  change  in  effec- 
tiveness. If  we  listen  to  a  loudspeaker  energized  by  a  power 
of,  say,  0.006  watt  (zero  level),  a  certain  loudness  level 
will  be  attained.  If  the  power  be  increased  by  0.006  watt 
(double),  the  same  increased  volume  of  sound  will  be 
noticeable  to  the  ear  as  if  a  loudspeaker  operating  at  40 
watts  were  increased  to  80  watts.   Many  people  find  it  in- 


conceivable that  the  same  increase  in  loudness  will  occur 
by  raising  the  power  output  of  an  amplifier  from  0.006 
to  0.012  watt  as  will  occur  in  raising  the  power  from  40 
to  80  watts. 

I  have  referred  thus  to  sound  and  power  because  it  is 
easier  to  understand  than  is  light.  Following  the  same 
basic  laws  in  terms  of  light,  the  same  degree  of  effective- 
ness will  be  realized  by  raising  screen  illumination  from  1 
footcandle  to  2  footcandles  as  will  result  from  raising  the 
illumination  from  50  to  100  footcandles.  Doubling  the 
power  into  a  loudspeaker  or  doubling  the  amount  of  light 
on  a  motion  picture  screen  results  in  an  effective  apparent 
increase  in  either  sound  or  light  intensity  which  is  just 
about  noticeable. 

The  presentation  by  over-anxious  salesmen  of  "facts'' 
which  in  themselves  are  unimportant  and  irrelevant  serves 
cnly  to  increase  the  confusion  of  those  who  do  not  fully 
understand  the  basic  laws  relative  to  light,  heat  and  sound. 

The  utilization  of  water  for  cooling  purposes  is  well- 
known  in  air-conditioning  plants.  Water  will  absorb  a  lot 
of  heat  (BTU's) — and  fast,  acting  much  like  a  sponge. 
When  water  has  absorbed  enough  heat,  it  is  dumped  down 
the  drain  along  with  the  heat. 

The  question  of  whether  to  air-cool  or  to  water-cool 
resolves  itself  into  a  simple  engineering  decision.  What 
is  the  most  efficient  means  for  taking  away  unwanted  heat? 
Air  may  be  used,  but  air  is  inherently  inefficient  as  a  heat- 
absorber  and  serves  only  to  transfer  the  heat  to  other 
metal  parts  of  the  mechanism  or  to  the  projection  room; 
in  other  words,  it  raises  the  temperature  of  all  surrounding 
air,  metal  parts,  etc.,  with  which  it  comes  in  contact. 

Advocates  Water-Cooling  for  Both  Lamp  and  Projector 

Water,  on  the  other  hand,  will  absorb  a  lot  of  heat  with- 
out raising  the  temperature  of  the  surrounding  air.  By 
adjusting  the  time  the  water  stays  in  contact  with  the 
heated  part,  the  amount  of  heat  absorbed  can  be  governed. 
When  the  temperature  of  the  water  rises  to  a  predeter- 
mined amount,  it  is  disposed  of  and  supplanted  by  fresh, 
cool  water.  Neither  the  surrounding  metal  parts  nor  the 
projection  room  air  are  heated  at  all. 

The  same  cooling  system  is  used  in  all  automobiles. 
Air-cooling  for  automobiles  has  been  tried  many  times, 
but  the  extremely  high  efficiency  of  water-cooling  has 
rendered  it  standard  automobile  engineering  practice. 
Without  water-cooling  we  could  not  possibly  enjoy  our 
modern  automobiles. 

Water-cooling  is  simple  and  effective.  It  can  be  used 
to  cool  the  arc  lamp,  the  metal  parts  and  the  projector 
over-all.  When  used  on  both  the  arc  lamp  and  the  projec- 
tor it  provides  an  effective,  economical  means  of  supplying 
the  cooling  now  so  urgently  needed  for  these  units.  I  am 
sure  that  time  will  prove  water-cooling  to  be  an  absolute 
"must"   for  modern  projection  equipment. 

By  WILLIAM  BORBERG 

Development  Engineer,  International  Projector  Corp. 

THE  article  in  IP  for  July  opens  the  way  for  a  much- 
'  needed  discussion  of  the  problem  of  cooling  projection 
equipment,  particularly  with  reference  to  light  sources  of 
high  brilliance  and  their  effect  upon  the  behavior  of  the 
film  during  projection.    Heretofore  this  problem  has  been 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


21 


serious  only  in  the  larger  theatres  and  in  drive-ins  where 
unusually  large  screens  are  used,  but  the  constant  improve- 
ment in  light  sources  and  equipment  generally  make  this 
topic  of  industry-wide  interest. 

It  should  be  borne  in  mind  that  the  film  absorbs,  mainly 
in  its  emulsion,  a  part  of  the  energy  contained  in  the  light 
beam.  It  is  this  absorbed  energy  which  causes  the  film  to 
deform  or  buckle  and,  at  too  high  a  light  level,  produce 
blisters  or  even  charred  areas  in  the  darkest  portions  of 
the  photographic  image. 

Heat-absorbing  light  filters,  arresting  a  high  percentage 
of  the  invisible  heat  rays,  are  used  to  good  advantage  in 
many  installations  having  high-intensity  arcs.  The  filter 
has,  of  course,  the  disadvantage  of  a  loss  of  visible  or  use- 
able light  in  the  order  of  from  10  to  20%,  varying  with 
the  type  of  glass  and  its  thickness ;  however,  it  will  prevent 
the  excessive  absorption  of  energy  by  the  film  emulsion, 
thus  reducing  the  deformation  of  the  film  image  exposed 
in  the  aperture. 

Excessive  Heat  Occasions  Strong  Negative  Buckle 

This  deformation,  usually  referred  to  as  "buckling,"  has 
a  direct  bearing  on  the  quality  of  the  screen  image.  A  slight 
buckle  toward  the  light  source  is  tolerable,  but  a  severe 
curvature  of  the  image  from  the  normal  plane  will  cause 
an  out-of-focus  effect  on  the  screen  whereby  either  the 
screen  center  is  relatively  sharp  in  focus  and  the  outer  por- 
tions are  not,  or  vice  versa;  or  only  a  poor  average  focus 
over-all  may  be  obtained. 

A  good  picture  can  never  be  projected  with  heavily 
buckled  film,  since  the  film  in  the  aperture  is  never  flat 
during  the  exposure  time  and  each  film  frame  moves  from 
the  normal  plane  to  its  maximum  buckled  position  twice. 
This  movement  is  riot  instantaneous,  it  takes  time,  thus  the 
film  is  in  focus  only  for  a  fraction  of  the  time  that  it  is 
projected  on  the  screen.  Such  momentary  deformation  of 
the  film  along  the  optical  axis  is  readily  detected  by  ob- 
servers with  a  trained  eye,  and  this  might  explain  IP's 
reference  to  "projectionists  who  insist  that  they  can  detect 
with  the  naked  eye  a  great  improvement  in  the  screen 
image"  after  heat  filters  are  installed. 

A  heat  filter,  used  in  connection  with  equipment  cur- 
rently available,  reduces  film  buckle  to  an  acceptable  level 
and,  furthermore,  protects  the  film  from  permanent  injury 
due  to  high  heat  levels,  such  as  lasting  buckle  or  embossing, 
which  renders  them  inferior  for  future  use,  even  when 
projected  at  comparatively  low  light  levels. 

Modern  heat-absorbent  glass  has  a  useable  light  trans- 
mission of  from  85  to  90%  and  a  high  rejection  rate 
for  light  in  the  infra-red  region.  The  greatly  improved 
screen  image  and  the  better  preservation  of  the  film  itself 
more  than  compensates  for  the  relatively  small  reduction 
in  light  on  the  screen. 

Film  Behaviour  With  and  Without  Heat  Filter 

The  accompanying  chart  shows  the  typical  difference 
in  behaviour  of  film  in  the  aperture  under  the  influence  of 
light  and  heat,  when  used  either  with  or  without  heat  filter 
between  the  light  source  and  the  film.  Displacement  meas- 
urements were  made  during  each  revolution  of  continu- 
ously-running loops — one  reading  at  the  center  of  the  film 
and  another  reading  at  a  point  near  the  edge  of  the 
aperture. 


The  figures  show  the  displacement  in  reference  to  the 
zero  deflection  point,  i.e.,  a  perfectly  flat  piece  of  film  in 
the  film  trap.  The  light  source  for  both  loops  was  a  175- 
ampere,  high-intensity  arc  with  F:2  condensers.  A  rear- 
shutter  with  53%  light  transmission  was  used.  The  light 
reduction  on  the  screen  due  to  the  filter  was  15%. 

It  should  be  noted  from  the  curves  on  the  chart  that  in 
projection  without  a  filter  a  considerable  difference  exists 
between  the  points  observed  and  the  reference  plane,  to  an 
extent  that  even  a  total  reversal  takes  place  after  a  few 
runs  of  the  loop,  from  a  negative  to  a  positive  buckle.  With 
filter,  the  displacement  of  the  observation  points  to  each 
other,  and  to  the  zero  plane,  is  considerably  reduced,  and 
during  the  entire  run  of  the  loop  the  buckle  remains  on  the 
negative  side. 

The  cooling  of  the  carbon  jaws  by  water  jackets  can 
hardly  have  any  effect  upon  the  heating  or  cooling  of  the 
film  in  the  aperture,  and  on  this  point  we  are  in  full  accord 
with  the  opinion  expressed  in  the  IP  article. 

Air  Blast  Directed  Upon  Film  at  Aperture 

The  air-cooling  of  the  film  in  the  aperture  has  been 
widely  used  for  about  25  years.  European  manufacturers 
adopted  this  method  mainly  to  promote  safety  rather  than 
to  obtain  an  increase  in  the  amount  of  light  flux  through 
the  film. 

A  pistol-range  target  projector,  built  about  35  years  ago 
in  this  country,  stopped  after  the  firing  of  a  shot  and,  in 
order  to  determine  the  marksman's  skill,  the  image  was 
kept  stationary  for  the  inspection  of  the  bullet  hole  on  the 
paper  screen.  A  series  of  fine  holes  around  the  aperture 
directed  a  stream  of  air  onto  the  film  emulsion,  thus  keep- 
ing the  film  cool  enough  to  prevent  ignition.  The  screen 
illumination  did  not  even  approach  today's  values,  nor 
was  picture  definition  up  to  the  present  standard,  other- 
wise these  pioneer  designers  would  have  had  to  wait  for 
the  recent  paper  by  Dr.  F.  J.  Kolb,  of  Eastman  Kodak  Co.* 

Dr.  Kolb  shows  that  a  dual  air-jet  arrangement  utilizing 
high- velocity  air  is  necessary  to  do  the  job  of  removing 
the  absorbed  heat  from  the  film  emulsion  and  simultane- 
ously directing  another  stream  of  air  against  the  film  base. 
This  method,  according  to  Dr.  Kolb,  permits  operation 
with  lamps  delivering  from  50  to  60%  more  light  than  is 
now  feasible.    The  air-jet  design  must  provide  a  fine  bal- 


*  "Air-Cooling     of     Motion     Picture     Film     for     Higher     Screen     Illumination,*' 
presented  at  the   Spring   1949   Convention   of   the   SMPE. 

Comparative  degree  of  buckle  when  film  loop  is  run  with  and  without 
heat-absorbent  glass  filters.    Buckle  figures  are  in  inches. 

Drawing   by   International   Projector   Corp. 

£+.030 


UJ 

z 


5  10  15  20 

NUMBER  OF  RUNS  PER  LOOP  — •>► 


22 


INTERNATIONAL    PROJECTIONIST 


September    1949 


ance  between  the  air  pressure  on  both  sides  of  the  film. 
The  emulsion  side  has  to  get  a  good  coverage  of  air  to 
dissipate  the  heat,  while  the  base  must  be  supported  so 
that  the  air  directed  upon  the  emulsion  side  cannot  cause 
the  film  to  buckle  in  a  positive  direction  towards  the  lens. 
Either  jet  alone  will  probably  be  inadequate.  The  rear 
jet,  on  the  emulsion  side,  will  remove  heat,  but  its  air 
current  may  cause  film  fluttering  and  a  poor  screen  image. 
It  is  reasonable  to  expect  that  the  front  jet  alone  will  have 
less  cooling  effect,  since  the  air  therefrom  contacts  the 
film  base  only,  while  absorbed  energy  from  the  light  is. 
at  the  moment  of  exposure,  entirely  on  the  other,  emulsion 
side.  Also,  the  front  jet  alone  will  tend  to  increase  the 
initial  negative  buckle,  due  to  the  heat  absorption  of  the 
emulsion,  unless  the  cooling  effect  of  this  jet  is  sufficiently 
large  to  carry  away  a  major  portion  of  the  heat. 

'Reduction  to  Practice'  Required  for  Air-Jet  Unit 

Thus,  air-jet  cooling  methods,  as  outlined  by  Dr.  Kolb, 
point  the  way  toward  further  improvement,  but  they  still 
must  be  reduced  to  practice  by  means  of  foolproof  designs 
which  are  simple,  reliable  and,  if  possible,  quiet.  The 
advantage  of  such  units  lies  in  the  fact  that  there  are  no 
light  losses,  thus  higher  screen  illumination  may  be  ac- 
commodated. However,  special  plumbing,  air  compressors, 
air  filters  and  separators  may  have  to  be  provided. 

Water-cooling  in  the  projector  has  been  employed  in 
several  European  designs.  It  was  used  to  prevent  the  heat- 
ing of  the  film  contacting  metal  parts  in  the  trap  and  the 
gate.  A  water-cooled  aperture  will  probably  act  likewise. 
However,  the  picture  area  of  the  film  itself  never  comes  in 
contact  with  any  units  of  the  film  trap,  and  it  is  in  this 
picture  area  where  the  heating  problem  is  most  serious  in 
terms  of  good  picture  presentation  and  film  preservation. 

It  can  hardly  be  assumed  that  sufficient  heat  is  conducted 
away  from  the  picture  area,  laterally,  to  the  outside  film 
edges  which  are  in  contact  with  the  cooled  metal  parts,  to 
prevent  buckling.  While  it  is  theoretically  possible  to 
effect  slight  pre-cooling  of  the  film  by  this  method,  it 
appears  that  it  will  be  less  effective  than  either  a  well- 
designed  heat  filter  or  air-blast  cooling  of  the  film. 

By  CHARLEY  HAHN 

President,  J.  E.  McAuley  Manufacturing  Co. 

II IGH  aperture  heat  first  became  a  serious  problem  back 
'  'in  1929-30  when  the  first  reflector  arc  lamps  using  the 
high-intensity  type  positive  carbon  (inadvertently  tagged 
"Hi-Lo")  began  to  be  generally  used.  At  that  time  pro- 
jector manufacturers  made  their  first  contribution  to  the 
solution  of  this  problem  when  they  changed  the  location 
of  the  shutter  from  in  front  of  the  projection  lens  to  its 
present  position  between  the  aperture  and  the  light  source. 

The  term  "light-heat"  used  herein  refers  to  the  thermal 
rise  which  follows  the  stoppage  of  all  or  any  portion  of 
the  radiant  energy  produced  by  a  35-mm  projection  arc 
lamp.  This  thermal  rise  (heat)  increases  proportionately 
with  the  amount  of  light  that  is  subtracted  from  the  total 
light  traversing  the  axis  of  the  projector  optical  system. 

Two  methods  are  presently  being  advocated  as  a  means 
to  afford  light-heat  protection  for  the  film:  the  use  of  heat- 
absorbing  glass  filters  which  are  inserted  in  the  light  beam 
between   the   aperture   and   the  light   source,    referred   to 


herein  as  the  "absorption  system,"  and  the  heat-radiation 
method  whereby  projector  parts  are  either  water-cooled  or 
subjected  to  air  blasts  from  jets  which  are  directed  against 
both  the  front  and  the  back,  or  edgewise  across  each  side, 
of  the  film  at  the  aperture. 

Eliminating  Heat  Before  it  Reaches  the  Film 

We  feel  that  the  absorption  method  is  the  only  one  that 
assures  positive  results,  the  only  one  that  is  definitely  and 
completely  protective,  because  it  actually  extracts  from  the 
light  beam  that  portion  of  the  total  heat  which  is  the  cause 
of  film  damage — before  this  heat  reaches  the  projector 
and  the  film.  Also,  this  method  results  in  lower  operating 
temperature  of  the  projector  mechanism  and  in  a  lower 
degree  of  heat  absorption  by  the  projection  lens. 

The  use  of  water-cooled  film  traps  and  gates  does  not 
in  any  way  reduce  the  initial  temperature"  impact  of  the 
light-heat  striking  the  projector  or  film.  This  system  can 
only  carry  off  the  higher  temperatures  that  are  absorbed 
by  projector  mechanism  parts,  hence  its  effectiveness  in 
reducing  the  temperature  of  the  film  itself,  either  before 
or  after  exposure,  is  open  to  considerable  question,  because 
such  water-cooled  parts  contact  the  film  only  on  its  outer 
edges. 

Such  water-cooling  systems  present  notable  installation 
complications,  because  a  water-circulating  means  must  be 
provided.  In  cold  weather  or  in  cases  where  the  normal 
temperature  of  a  water  supply  is  rather  low,  a  moist  con- 
densation may  accumulate  on  the  cooled  projector  parts. 
Humid  weather  will  also  promote  such  condensation. 

Water-cooled  projector  parts  (and  this  applies  also  to 
air-cooling)  cannot  reduce  the  initial  thermal  content  of 
the  light  beam  striking  the  film,  thus  if  a  high  level  of  screen 
illumination  is  made  possible  through  their  use,  it  naturally 
follows  that  the  projection  lens  will  reach  a  proportion- 
ately higher  operating  temperature  due  to  higher  heat 
absorption. 

An  air  stream  blowing  on  the  exposed  film  at  the  aper- 
ture opening  is  also  a  heat-radiator,  the  only  difference 
being  that  the  medium  is  air  instead  of  water.  A  com- 
pressed air-cooling  system  also  has  the  complication  of  a 
suitable  piping  system  to  be  installed,  as  well  as  equalizing 
valves  to  control  the  jets  of  air  to  prevent  the  bending  or 
bellying  of  the  film  at  the  aperture  because  of  an  unequal 
air  pressure. 

Possible  Mechanical,  Maintenance  Difficulties  Cited 

To  maintain  an  adequate  air  capacity  and  pressure,  a 
compressor  would  have  to  be  powered  by  at  least  a  2-h.p. 
motor.  It  may  have  to  operate  almost  continuously,  hence 
there  is  a  sizeable  current  cost  to  be  considered.  Such  a 
system  should  also  have  a  fairly  large  expansion  tank,  so 
that  the  compressed  air  may  cool  before  it  is  blown  on 
the  film.  The  tank  should  also  have  a  safety  valve.  To 
prevent  an  excessive  accumulation  of  airborne  dirt  and 
moisture  in  and  around  the  projector  mechanism  and  on 
the  projection  lens  (which  would  effect  focus),  a  better 
than  ordinary  air  filter  and  drier  must  be  used.  Finally, 
there  will  be  a  relatively  high  maintenance  cost,  and  ever 
the  possibility  of  oily  mist  accumulating  on  parts  adjacent 
to  the  air  jets  because  of  oil  leakage  from  the  compressor 
cylinders,  pistons  or  rotors,  as  they  become  worn. 

If   a  motor-driven   centrifugal  blower   or  a  rotary  air 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


23 


pump  be  used  for  the  air  supply,  instead  of  a  compressor, 
adequate  filtration  of  airborne  dust  and  moisture  becomes 
a  more  difficult  problem,  because  such  a  source  cannot 
build  up  the  necessary  pressure  to  force  the  air  through 
efficient  air-filtering  mediums.  The  ever-present  collection 
of  dirt  and  oily  smudge  that  is  seen  around  air  vents  of 
exhaust  fans,  ventilating  and  air-conditioning  systems,  etc., 
is  evidence  of  this,  and  it  is  logical  to  assume  that  such 
accumulations  of  dirt  will  likewise  occur  in  the  projector 
mechanism. 

Possible  mechanical  failure  of  motors,  compressors, 
blowers,  air  pump;  replacements  of  filters  and  maintenance 
all  contribute  to  a  high  cost  of  operation. 

Air-Cooling  Induces  In-and-Out-of-Focus  Effect 

We  all  know  that  as  film  passes  through  the  projector, 
the  sprockets,  guide  rollers,  film  tracks,  tension  shoes,  etc., 
only  come  in  contact  with  it  for  a  width  approximately 
equal  to  the  width  of  the  sprocket  hole  area  on  each  edge; 
also,  that  a  centre  clearance  area  is  provided  for  each 
face  of  the  film  to  prevent  scratches  and  damage  to  the 
emulsion  and  plain  side  of  the  photo  frame  area. 

In  our  original  work  with  air-cooling  systems,  we  found 
that  when  only  slightly  warped  film  was  used,  any  air 
draft  of  sufficient  volume  to  do  any  radiating  of  heat  at  all 
would  cause  a  higher  rate  of  in-and-out-of-focus  fluttering, 
at  the  aperture,  than  is  normally  experienced  when  no  air 
draft  was  used,  and  that  such  fluttering  tendency  was 
markedly  increased  when  the  air  was  directed  across  both 
sides  of  the  film  from  an  edgewise  position. 

It  is  erroneous  to  assume  that  just  because  aperture  air- 
cooling  made  practical  in  great  measure  the  present  method 
of  process  background  projection  in  the  studios,  it  will 
likewise  solve  the  problem  of  aperture  heat  for  theatre  pro- 
jection: the  projection  principles  involved  are  wholly  differ- 
ent and  unrelated. 

Simplicity,  Efficiency  of  Absorption  Method  Cited 

The  absorption  system,  on  the  other  hand,  is  extremely 
simple  and  definitely  effective.  It  entails  no  high  installa- 
tion cost,  no  operating  complications,  and  no  high  operat- 
ing cost.  An  absorption  heat  filter  requires  only  a  1/50-h.p. 
motor  to  operate  the  blower  which  cools  the  filter  glasses, 
and  this  motor  runs  only  when  a  particular  projector  is 
operating. 

Widely  circulated  is  the  wholly  erroneous  impression 
that  the  use  of  a  glass  heat  filter  will  result  in  a  20% 
loss  of  visible  light.  This  round  percentage  figure  un- 
doubtedly  originated    (and  would  more   or  less   correctly 


apply)  to  the  first  internally-colored  heat-filter  glass  to 
become  commercially  available,  the  Aklo  Nos.  395  and 
3966  glass  having  a  thickness  of  2  mm.  Here  it  should  be 
emphasized  that  a  light-transmission  curve  will  vary  ma- 
terially depending  upon  the  thickness  of  the  glass  used. 

For  example,  the  aforementioned  Aklo  No.  3966  glass, 
having  a  thickness  of  2  mm,  is  known  to  have  an  optimum 
heat-absorption  ratio  of  70%  and  an  optimum  visible  ray- 
transmission  ratio  of  80% — a  light  loss  of  20%.  But  we 
have  always  used  a  glass  of  only  1%  mm  thickness  which 
transmitted  84%  of  the  light.  Now  comes  the  newly-de- 
veloped phosphate-type  glass  which  in  \V%  mm  thickness 
passes  86%  of  the  visible  light  rays! 

Number  of  Glass  Strips  Used  is  Elective 

A  complete  filter  glass  unit  consists  of  a  metal  frame 
with  provision  to  hold  a  total  of  eight  strips  of  glass.  The 
two  outer  strips,  in  inches,  are  %  x  3,  while  the  other  six 
strips  are  each  %  x  4.  All  these  strips  are  only  l1/^  mm 
thick.  The  strips  are  removable,  thus  only  as  many  need 
be  used  in  the  light  beam  as  are  required  to  prevent  film 
damage  at  the  particular  current  drawn  by  the  arc. 

With  the  entire  eight  strips  in  use,  the  average  total 
visible  screen  illumination  loss  is  at  most  14%.  When 
only  three  or  four  strips  are  required  to  prevent  damage, 
this  light  loss  can  be  reduced  to  approximately  7  or  8%, 
a  practice  that  is  utilized  by  many  installations  using  170 
amperes  at  the  arc.  The  removal  of  porthole  glass  com- 
pensates almost  entirely  for  the  visible  light  loss  occa- 
sioned by  the  filter  glass. 

It  would  seem  that  too  little  attention  has  been  paid  to 
the  possibility  of  pre-cooling  the  film  before  it  is  exposed 
to  the  heat  at  the  aperture,  that  is,  at  some  point  within 
the  projector  mechanism  between  the  upper  magazine  fire 
trap  and  the  aperture,  or  between  the  upper  magazine  and 
the  top  of  the  projector  mechanism. 

Such  a  method  is  entirely  feasible,  either  by  means  of 
an  air-cooled  chamber  through  which  the  film  would  travel 
or  by  cooled  air  which  could  be  blown  directly  against  the 
film.  A  very  small  mechanical  refrigerating  unit  could  be 
so  designed  that  the  degree  of  pre-cooling  could  be  defi- 
nitely controlled,  manually  or  automatically  by  a  thermo- 
stat. The  radiation  of  heat  while  the  film  is  being  rewound, 
or  the  provision  of  cooled  storage  compartments,  are  other 
possibilities. 

It  seems  pertinent  to  mention  here  that  irrespective  of  the 
type  of  high-intensity  lamp  used,  or  the  carbon  trim  used, 
or  the  arc  amperage,  it  is  authoritatively  conceded  that 
with   the  present  average  range   of  photographic   density 


Kodak's  New  Ektalite  Lens 

Kodak's  Ektalite  field  lens  is  something 
new  in  photographic  equipment.  It's  being 
used  in  the  new  Kodak  Reflex  II  camera  and 
in  the  Kodaslide  Table  Viewer.  For  a  clear 
understanding  of  how  this  lens  works,  look 
at  the  accompanying  three  sketches. 

The  usual  twin-lens  camera  has  a  viewing 
lens  that  transmits  the  subject  image  to  a 
mirror,  which  reflects  it  to  the  ground  glass 
screen.  The  light  rays  (as  shown  by  the 
figure  at  the  left)  tend  to  go  in  straight  lines 
through  the  screen.  But  the  image  loses 
brightness,  except  in  the  very  center  of  the 
screen. 


Now  notice  the  center  diagram.  It  shows 
a  condenser-type  field  lens  below  the  screen. 
This  bends  the  light  rays  upright  and  fun- 


Comparative  quality  of  Ektalite  lens. 


nels  them  directly  to  one's  eyes.  But  this  type 
is  relatively  heavy,  bulky  and  often  causes 
fuzzy  images.  In  short,  it's  not  very  practical. 

The  sketch  at  the  right  reveals  what  the 
Ektalite  lens  achieves.  It  does  what  the  con- 
denser lens  did  without  the  condenser's  op- 
tical drawbacks. 

A  series  of  precise  grooves — 200  to  an 
inch — on  the  face  of  the  lens  "reproduce" 
the  over-all  curve  of  the  condenser  lens  sur- 
face. Thus  the  condenser  lens,  in  effect,  has 
been  "flattened"  into  a  thin  plastic  sheet. 
Placed  below  the  ground  glass  in  the  camera, 
the  Ektalite  lens  does  the  job  of  a  standard 
condenser  lens  nine  times  as  heavy  and  20 
times  as  thick! 


24 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


the  absolute  top  level  of  screen  illumination  it  is  safe  to 
use  is  16,000  lumens.  This  refers  to  measurement  without 
film  in  the  projector,  without  shutter  losses,  without  port 
glass  losses,  and  with  an  efficient  and  accurately  aligned 
optical  system. 

It  seems  perfectly  clear,  therefore,  that  without  some 
means  of  light-heat  protection  for  the  film,  the  mere  use 
of  a  certain  type  of  carbon  combination  having  a  stated 
maximum  screen  lumen  output  at  a  certain  amperage,  in 
a  lamp  having  a  particular  diameter  reflector  and  F  light 
speed — all  this  is  no  indication  that  a  level  of  screen 
illumination  higher  than  16,000  lumens  will  be  obtained. 
If  a  higher  level  of  screen  light  actually  did  result  there- 
from, film  damage  in  varying  degree  would  be  experienced 
at  some  time  or  other,  or  possibly  all  the  time. 

The  foregoing  comment  should  not  be  construed  as  a 
criticism  of  any  particular  manufacturer's  product;  rather 
is  it  a  summary,  as  the  writer  sees  it,  of  ten  years'  experi- 
ence with  this  particular  problem. 

By  H.  T.  MATTHEWS 

President,  Motiograph,  Inc. 

THE  ADVENT  of  the  drive-in  theatre  with  its  tremendous 
screen  area  has  intensified  the  search  for  greater  light- 
producing  capacity  from  projection  equipment.  With 
existing  limitations  on  the  efficiency  of  shutters  of  all  pres- 
ent types,  efforts  have  been  devoted  in  the  main  to  increas- 


ing the  output  of  the  light  source.  Since  increased  light 
means  increased  heat  on  the  projector  and  the  film,  the 
problem  is  complicated  by  the  need  for  providing  effective 
means  for  cooling. 

First,  let  us  not  confuse  water-cooled  positive  contacts 
in  the  lamphouse  with  film-cooling  or,  for  that  matter,  with 
known  means  for  improving  light  production.  Though 
claims  for  improved  light  with  this  method  have  been 
made,  they  are  contrary  to  laboratory  findings  (except 
under  special  conditions),  and  no  one  has  yet  demonstrated 
just  how  such  claimed  increase  is  achieved. 

Water-cooling  the  lamphouse  may  have  beneficial  effects 
with  respect  to  increasing  the  life  of  contact  parts  in  some 
makes  of  lamps,  making  lamp  parts  cooler  to  handle  and, 
possibly,  decreasing  carbon  consumption;  but  our  tests 
here  at  Motiograph  have  not  progressed  sufficiently  to 
enable  us  to  substantiate  any  claims  regarding  light  output. 

In  any  event,  the  heat  on  the  aperture  and  the  film  is 
radiated  from  the  lamphouse  mirror  or  condenser,  as  the 
case  may  be,  and  the  cooling  of  the  carbon  jaws  cannot 
possibly  affect  this  situation — unless,  of  course,  it  should 
be  found  that  water-cooling  at  this  point  actually  reduces 
the  amount  of  light  produced. 

Cites  80-Ampere  Level  as  Threshold  of  Danger 

Any  carbon  arc  lamp  operating  at  80  or  more  amperes 
gets  into  the  range  where  heat  becomes  a  problem.    The 
use  of  filters  to  reduce  this  heat  has  been  tried  with  some 
(Continued  on  page  34) 


.;  • 


Giant  "Drive -In"  Images 

with 


Edge-to-Edge  Sharpness 


•  For  the  toughest  projection  job  .  .  . 

producing  clear,  critically  defined,  uniformly 

brilliant  giant  images  on  "Drive-In"  Theatre  screens 

.  .  .  Bausch  &  Lomb  Super  Cinephor  lenses  are 

preferred.  Only  screen  images  easy  to  look  at  with 

edge-to-edge  sharpness  satisfy  theatregoers.  Be  sure  your 

screen  images  are  the  best .  .  .  specify  Bausch  &  Lomb 

Super  Cinephor  projection  lenses.  Bausch  &  Lomb  Optical 

Co.,  616-1  St.  Paul  St.,  Rochester  2,  N.Y. 


FOR   TOP    IMAGE    QUALITY  ON   YOUR    SCREEN  ...  THE  W  TRADEMARK   ON    YOUR   LENS 


BAUSCH  &  LOMB 


PROJECTION  LENSES 


INTERNATIONAL    PROJECTIONIST 


September    1949 


25 


supi:k-s: 


|Ww      . 


SEALED 

LENS  ELEMENTS 


,  ONE-PIECE 
'  MOUNT 


ANODIZED 
FINISH 


COATED 
'  OPTICS 


f/ 


&* 


WHY  ARE  SHORT  FOCAL  LENGTH  LENSES  USED  FOR  DRIVE-INS? 
Where  the  projection  room  must  be  located  near  the 
screen,  short  focal  length  lenses  are  necessary  to  pro- 
ject large  pictures.  For  this  reason  lenses  with  focal 
lengths  from  2"  to  3V2"  are  usually  used  in  Drive-Ins. 
The  Eollmorgen  Screen  Chart  shows  the  focal  length 
needed  for  pictures  from  9  to  85  ft.  wide  at  40  to  400  ft. 
throws. 


DO     SHORT 
PICTURES? 


FOCAL     LENGTH     LENSES     GIVE     HIGH     QUALITY 

Short  focal  length  lenses  for  wide  angle  projection  are 
quite  difficult  to  design,  but  special  attention  was 
given  to  this  phase  in  computing  the  Super-Snaplites. 

DOES    THE    PICTURE    PROJECTED    BY    A    SUPER-SNAPLITE    HAVE 
THE  SAME  QUALITIES  IN  ALL  FOCAL  LENGTHS? 

Yes.  Due  to  the  unique  design  of  the  Super-Snaplite, 
the  picture  projected  by  a  2"  lens  shows  as  good  defi- 
nition, flatness  of  field  and  uniformity  of  light  as  with 
the  more  popular  sizes  such  as  4"  or  4V2". 

ARE  THE  SIZES  OF  THE  VARIOUS  ELEMENTS  THE  SAME  FOR  ALL 
FOCAL  LENGTHS? 

No — the  elements  are  designed  for  each  focal  length 

and  vary  in  size. 

WHAT  IS  THE  TOLERANCE  IN  FOCAL  LENGTHS  OF  SNAPLITES? 

Snaplite  lenses  are  all  within  the  tolerance  of  plus  or 
minus  1%  recommended  by  the  Society  of  Motion  Pic- 
ture Engineers. 


IN   ACTUAL 
MEAN? 


PRACTICE   WHAT    DOES    THIS    PLUS    OR   MINUS    1% 


Gt&Ki 


It  means  that  the  actual  picture  size  for  any 
focal  length  lens  will  be  within  plus  or  minus 
1%  of  the  computed  picture  size.  Thus  if  a  20 
ft.  (240")  wide  picture  is  desired,  the  actual 
projected  picture  might  be  238"  or  242"  and 
still  fall  within  the  accepted  tolerances. 


"You  Get  the  Most  Uniform  Light  with  Super-Snaplite' 

mhj.a\oim;!Fn     . 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


r® 


LENS  AND  FILM  FACTORS 

(Continued  from  page  8) 

gate,  may  be  such  that  a  perfect  focus 
is  a  physical  impossibility. 

The  function  of  the  film  gate  is  simply 
to  hold  the  film  in  correct  lateral  align- 
ment and  perfectly  flat  and  motionless 
while  each  individual  frame  is  projected. 
If  the  gate  fails  to  hold  the  film-photo- 
graph flat  and  square  to  the  lens,  the 
definition  of  the  projected  image  will  be 
poor.  Yet  many  times  the  lens  is  blamed 
for  out-of-focus  effects  which  are  really 
due  to  failure  of  the  gate  to  perform  its 
simple  function. 

The  effects  produced  by  worn  gate 
runners  (film  trap  shoes)  are  frequently 
very  pronounced,  making  it  impossible  to 
secure  a  uniformly  sharp  focus  on  all 
areas  of  the  screen,  even  with  the  best  of 
lenses.  Sometimes  the  left-  and  right- 
hand  sides  of  the  screen  differ  in  focus, 
and  very  often  one  corner  (usually  the 
lower  right-hand  corner  of  the  screen  im- 
age) is  blurred  when  all  other  parts  of 
the  picture  are  perfectly  sharp.  The  fol- 
lowing test  serves  to  determine  whether 
the  lens  or  the  film  gate  is  at  fault  when 
only  one  part  of  the  picture  is  blurred: 

Project  a  reel  of  pictures  known  to 
have  good  definition.  While  the  reel  is 
running,  loosen  the  lens  holder  and  ro- 
tate the  lens  barrel  a  quarter  of  a  revolu- 
tion or  more.  Refocus  and  note  the  image 
definition.  If  the  blurred  area  has  shifted 
to  another  side  or  corner  of  the  screen, 
something  is  wrong  with  the  lens. 

If,  on  the  contrary,  the  blurred  portion 
ol  the  picture  remains  in  the  same  region 
of  the  screen  no  matter  how  the  lens  is 
turned,  the  film  runners  (trap  shoes)  are 
worn  and  need  replacement. 

Periodic  testing  of  the  flatness  of  the 
film  trap  shoes  with  a  short  steel  straight- 
edge is  good  practice,  but  it  does  not 
compare  with  the  aforementioned  actual 
projection  test  for  tracking  down  poor 
image  definition  arising  from  hollow- 
worn  shoes.  Shoes,  or  runners,  must  also 
be  replaced  if  the  film  has  grooved  them 
longitudinally.  (Draw  a  sharp-edged 
copper  coin  across  the  shoes  laterally. 
The  tell-tale  "click"  indicates  grooving. 
Detection  of  grooving  is  more  difficult  in 
the  case  of  Simplex  E-7.) 

Uneven  hollowing  of  the  film  shoes 
may  be  traced  to  worn  and  incorrectly 
adjusted  gate  tension  pads  (film  trap- 
door pads). 

Image  definition,  even  though  limited 
by  the  quality  of  the  lens  and  the  print, 
is  largely  a  matter  of  projection  practice. 
The  attainment  of  the  most  perfect  defi- 
nition which  the  print  allows  is  one  of 
the  most  valuable  contributions  the  pro- 
jection craft  can  make  to  the  continued 
success  of  professional  movies. 


26 


INTERNATIONAL   PROJECTIONIST     •     September    1949 


TELECASTS 

(Continued  from  page  15) 

mixture  is  broken  down  into  the  three 
primary  signals  carrying  the  different 
colors.  These  then  are  fed  simultaneous- 
ly onto  a  screen  to  give  the  single,  full- 
color  picture. 

The  CBS  mechanical  system  uses  the 
sequential  method  of  transmission — 
sending  the  picture  first  in  one  color  and 
then  in  another,  the  eye's  persistence  of 
vision  giving  the  finished  image. 

Noting  that  the  receiver  market  al- 
ready was  subject  to  severe  price-cutting, 
dealers  expressed  the  fear  that  the  public 
might  believe  that  color  would  be  here 
almost  immediately  and  hesitate  to  buy 
receivers.  This  viewpoint  was  buttressed 
by  a  statement  by  Emerson  Radio  Corp., 
which  holds  that  there  is  a  "remote  pos- 
sibility" that  color  Tv  receivers  will  be 
available  to  the  public  by  1953.  "It 
would  now  cost  anywhere  from  $300  to 
$500  to  build  a  converter  to  receive  color 
— that  is,  to  build  them  on  a  mass-pro- 
duction basis  and  not  handmade  lab 
units.  A  set  to  receive  both  color  and 
b-and:w  should  sell  for  about  $1000." 

This  color  Tv  situation,  if  it  slows  up 
materially  the  sale  of  receivers,  might 
give  the  motion  picture  industry  a  much- 
needed  breathing  spell  until  it  gets  its 
own  Tv  and  other  technical  programs  in 
older;  but  if  home  Tv  proves  to  have 
the  wide  audience  appeal  that  some  quar- 
ters attribute  to  it,  the  respite  will  be 
in  any  event  of  brief  duration. 


Altec's  New  Quality  Tv  Receiver 

Newest  entry  into  the  high-quality  tele- 
vision   market   is    Altec    Lansing    Corp., 

Correction,  Please 

In  the  August  issue  of  IP  (p.  28)  there 
appeared  a  picture  of  Ray  Colvin,  secre- 
tary of  TEDPA,  accompanied  by  a  cap- 
tion which  described  him  as  Roy  Boomer, 


Roy  Boomer 

Sec.-Treos.   of 

TESMA.  This 

photo  warranted 

authentic. 


whose  likeness  is  reproduced  herewith. 
Both  handsome  guys  and  both  devoted 
to  the  big  equipment  show  staged  jointly 
by  their  respective  organizations  each 
year  (this  time  in  Chicago  Sept.  26-28). 
Excuse  it,  please. 


long  recognized  as  specialists  in  the  pro- 
fessional sound  reproduction  field,  nota- 
bly the  motion  picture  industry. 

Bringing  their  20-year  professional 
know-how  in  relating  sound  to  sight  in 
both  the  production  and  theatre  phases 
of  motion  pictures,  Altec  Lansing  asserts 
it  has  brought  to  Tv  for  the  first  time  a 
quality  of  sound  reproduction  commensu- 
rate with  the  most  advanced  design  on 
the  visual  side,  stressing  that  it  has  de- 
liberately aimed  at  the  "high  end  of  the 
high-quality  market"  and  will  not  "mass- 
produce  for  the  hot-dog  market."  The 
new  receivers  are  in  production  in  Altec 
Lansing's  own  factory  in  California  on  a 


strictly  limited  production  schedule  of 
only  200  a  month. 

Featured  specifications  include  as  "a 
new  and  unique"  easy-turning  channel 
selector  to  provide  for  positive  station 
tuning,  an  exclusive  video  circuit  design 
which  improves  picture  quality  by  40%, 
a  12%-inch  picture  tube,  and  an  8-inch 
400B  Dia-Cone  speaker  which  produces 
audio  quality  superior  to  that  of  competi- 
tive receivers  costing  more  than  $2,000. 

Table  and  consolette  models  are  fur- 
nished in  mahogany,  walnut  or  blonde 
finish.  Selling  prices  are  $367,  $408,  and 
$308  for  table,  consolette,  and  chassis, 
respectively. 


UMafetM^ 


REQ.     U.    5.     PAT.    OFF. 


JVU 


The  Standard  of  Constant  Power  Supply 


Throughout  the  years 


For  more  than  three  decades,  thousands  of  Transverters  have 
been  installed  in  leading  theatres  everywhere.  Theatre  operators 
know  there  is  nothing  better  than  a  Transverter  for  the  sure  way 
to  get  reliable  performance,  constant  screen  illumination,  quiet 
operation,  low  operating  cost  and  long  life.  You  can  profit  by 
the  experience  of  others  and  solve  your  projection  room  require- 
ments   with    the    best— a    Hertner    motor-generator    Transverter. 

Distributed    by 

NATIONAL    THEATRE    SUPPLY 

In  Canada:    GENERAL    THEATRE    SUPPLY    COMPANY 


THE  HERTNER  ELECTRIC  COMPANY 

12690  ELMWOOD  AVE.  •  CLEVELAND  11,  OHIO 

A  General  Precision  Equipment  Corporation  Subsidiary 
MOTOR-GENERATORS    •    GENERATOR    SETS 


MOTORS    • 


INTERNATIONAL    PROJECTIONIST 


September    1949 


27 


NEW  16-MM  LENS  SERIES 

(Continued  from  page  17) 

and  with  no  shutter  or  film  in  the  gate, 
theoretically  it  should  be  possible  to 
deliver  approximately  605  lumens  to  the 
screen.  Assuming  a  shutter  efficiency  of 
50%,  this  would  reduce  to  302  lumens. 
The  previously  mentioned  ASA  speci- 
fication requires  under  the  same  condi- 
tions 275  lumens  with  65%  average  cor- 
ner-to-center distribution.  A  Navy  speci- 
fication   requires    the    same    lumen    out- 


put,   but    with    75%    average    corner-to- 
center  distribution. 

Obviously,  then,  in  order  to  reach  the 
required  total  lumen  output,  practically 
all  of  the  F:1.6  speed  of  the  entire  sys- 
tem must  be  utilized.  Inherently,  any 
lens,  as  is  well  known,  will  transmit  less 
light  the  farther  off  the  axis  we  go.  In 
the  case  of  the  2-inch  Super  Cinephor 
16,  which  will  vignette  the  most  since  it 
is  the  shortest  focal  length  in  the  series, 
there  is  about  a  30%  loss  of  light  in  the 
extreme  corner  of  the  16-mm  frame. 


Your  Silent  Partner 

in  the  Projection  Room 


We  are  proud  of  our  23  year$  of 
service  as  "Silent  Partners"  to  the 
projectionists  of  America. 

You  put  the  show  on! 

We  help  you  keep  it  on  —  maintain 


screen  presentation  at  its  best! 


Now—as  always  across  the  years  — 
you  can  rely  on  NATIONAL— in  any 
emergency  —  24  hours  a 
necessary! 


day    if 


When  you  think  of  equipment , .  .supplies  .  ♦ , think 

NATIONAL.    We're   as   near   as   your   telephone  — 

ready  and  waiting  fa  be  of  servitel 


NATIONAL 

■lilWIlWIHJf 

Divide**  el  National  .Simplex  •  Sluow arth. I r. 


A  Petzval-type  lens,  because  ot  its 
simpler  construction,  vignettes  under  the 
same  conditions  anywhere  between  20 
and  30%,  depending  on  the  lens  and 
whether  or  not  it  has  a  field-flattening 
element.  Therefore,  the  requirement  of 
75%  corner-to-center  uniformity  demands 
not  only  a  100%  efficient  condenser,  but 
actually  in  most  cases  a  deliberate  re- 
duction of  light  in  the  center  of  the  field. 

This  can  be  done  in  the  condenser 
design,  but  obviously  it  will  reduce  the 
total  lumen  output  and,  as  already  stated, 
there  is  practically  no  room  to  move  in 
this  direction.  Therefore,  even  at  best 
to  meet  the  illumination  requirements 
as  aforementioned,  it  requires  a  very 
delicate  balance  between  total  output 
and  uniformity. 

65%  Center-to-Side  Distribution 

Coupled  with  the  fact  that  it  is  al- 
most impossible  to  design  a  perfect  con- 
denser, and  with  the  many  other  vari- 
ables in  the  system  such  as  variation  in 
light  sources  and  misalignment  of  the 
optical  system,  it  is  felt  that  the  afore- 
mentioned specifications  are  not  realistic 
for  practical  projector   performance. 

However,  under  carefully  controlled 
conditions,  and  with  a  well-designed  con- 
denser, 65%  corner-to-center  uniformity 
with  approximately  550  total  lumens 
(with  no  shutter)  can  be  achieved  with 
an  F:1.6  Super  Cinephor  16  lens,  and  a 
750-watt,  25-hour  lamp.  This  represents 
about  the  limits  that  can  be  obtained 
without  resorting  to  faster  lenses  or 
different  light  sources. 

Finally,  in  keeping  with  the  design 
requirements    of    projection    lenses,    so 

(Continued  at  foot  of  next  page) 


Star  fienfonmcutce   with  STAR  CORE 


JLonflA^  ctn)^ 


STAR  CORE,  exclusive  feature  with  the  }•""'"•  c°,b°n'  °"  ""''"J'T'V  \  \  i  W            \ 

'  the     lorgeil     theatres     m     the     U.     o.    and  y?                   Jr  Vl' 

Lorraine    CorbOnS  —  a    manufacturing  throuohoul Ihe  world  i/ie  Lorraine  Corbon..  \ 

process  that  increases  the  performance                  •Feaiured  in  our  horizontaiieod  -hse.  r 

Of  the  CarbOnS.  .opcer-roaled  rorbon,. 

A  more  brilliant,  steadier,  more  con-  write  for  distribution  data 

sistent  white  light — more  economically                PAQDftMC      IMP  / 

...proven  facts  as  shown  by  tests                 ImlluUPlO,    IllU.  ^- 

made  under  actually  operating  con-                   BOONTON,  N.J.  M, 

dltlOnS.  UEUI    vnoti.    a-jn    1A/C<T    zl/WV,    5TDCCT  V 


NEW  YORK:  234  WEST  44th  STREET 


WITH   ANY 


LAMP 


IN  ANY  SIZE     THEATRE 


SAM  SCHWARTZ— Owner,  Aztec 
and  Yolanda  Theatres,  Eagle  Pass, 
Texas — declares: 

"I  have  used  RCA  Service 
continuously  for  the  past  20 
years.  Service  has  been  prompt 
and  very  efficient.  It's  a  sound 
business  investment." 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


28 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


All  This,  and  the  Movies  Too: 
Drive-Ins  as  Seen  by  Time' 

Copyright  1949  by  Time  Magazine 

Within  the  year,  U.  S.  drive-in  theatres 
had  doubled :  more  than  i,uvO  sprawled 
under  the  sky  in  45  states,  and,  with  at  least 
100  more  on  the  way,  the  sky  seemed  to  be 
the  limit.  While  indoor  exhibitors  gloom  over 
a  20%  drop  from  last  year's  box-office  take, 
Variety  reported  a  10%  boost  in  drive-in 
business. 

Drive-ins  .  .  .  and  "airers,"  could  also 
point  to  a  recent  triumph  over  man  and  na- 
ture. In  Denver  recently,  a  once  skeptical 
Hollywood  had  staged  its  first  world  pre- 
miere at  an  ozoner.  Heavy  rain  lashed  at 
the  arena,  but  to  see  a  Western  7,000  of 
the  faithful  waited  for  two  hours  in  1500 
cars. 

Barbecue,   Bingo — and   Movies 

From  their  modest  start  in  Camden  (N.J.) 
in  1933,  the  drive-ins  have  grown  too  big 
to  be  dampened  by  rain.  They  woo  the  fam- 
ily trade  with  an  imposing  sideshow  of  pic- 
nic areas,  merry-go-rounds,  dance  floors, 
shuffleboard  courts  and  bottle-warming,  car- 
washing  and  laundry  service.  Among  the 
latest  gimmicks,  planned  or  already  drawing 
customers  to  the  airers:  nightclubs,  golf- 
driving  ranges.  Shetland  ponies,  barbecue 
pits  and  motorized  bingo  (the  jackpot  goes 
to  the  right  speedometer  mileage). 

All  this,  plus  the  movies,  takes  as  big  an 
investment  as  a  regular  cinemansion:  one 
2,000-car  ozoner  near  Cincinnati  cost  $750,- 
000.  But  the  payoff  is  heavy  and  swift.  Ex- 
ample: the  atmosphere  under  artificial  moon- 
glow  whets  appetites  so  keenly  that  popcorn, 
hotdogs  and  hamburgers  sell  about  four 
times  as  well  at  ozoners  as  in  theatres.  Some 
drive-ins  can  pay  all  expenses  with  the  re- 
ceipts from  munching. 

New  Moviegoers  Bulk  of  Audience? 

One  outdoor  impresario  estimates  that 
80%  of  drive-in  fans  are  not,  and  never  have 
been,  regular  indoor  moviegoeri.  The  best 
customers  are  (1)  moderate-income  families 
who  bring  the  children  to  save  on  baby-sit- 
ting (2)  the  aged  and  physically  handi- 
capped and  (3)  farmers  and  factory  workers 
clucking'  the  ritual  of  dressing  up  to  go  to  a 
movie  in  town.  The  drive-ins  are  also  popu- 
lar with  young  neckers,  but  exhibitors  deny 
that  their  places  are,  in  Variety's  phrase, 
"passion  pits  with  pix."    Their  righteous  de- 

NEW  16-MM  LENS  SERIES 

that  they  be  in  every  way  comparable  to 
larger  lenses,  the  Super  Cinephor  16's 
are  held  in  manufacturing  to  a  focal 
length  tolerance  of  ±  1%.  This  elimi- 
nates the  necessity  of  matching  when  the 
lenses  are  used  in  pairs  in  the  usual 
manner  in  continuous   projection. 

[The  author  acknowledges  those  who  did 
most  of  the  actual  optical  and  mechanical 
design  referred  to  in  this  article  namely, 
the  late  Dr.  W.  B.  Rayton,  Miss  Lena  M. 
Hudson,  Dr.  K.  Pestrecov,  Mr.  C.  DeGrave, 
and  Mr.  D.  Gottschalk.] 


fense:   nothing  happens  that  doesn't   go  on 
in  a  balcony. 

Most  ozoners  get  by  nicely  with  old  mov- 
ies, but  many  are  clamoring  for  a  chance  to 
show  the  latest  pictures:  four  Illinois  drive- 
ins  are  suing  for  earlier  showings.  Another 
growing  pain:  at  least  three  state  legislatures 
are  talking  about  regulating  or  taxing  the 
drive-ins,  and  some  local  officials  have 
banned  them  as  road  hazards  because  they 
disgorge  hundreds  of  cars  at  once. 

Owners'  Resourcefulness  Overcomes  Handicaps 

The  battle  against  the  elements  is  pro- 
gressing. Airers  have  found  a  glycerine  com- 
pound which  is  sprayed  on  windshields  to 
drain  off  the  downpour  in  transparent  sheets 


instead  of  driblets.  Steel  reinforcement 
keeps  60-by-50  feet  screens  from  toppling  in 
high  winds.  For  mosquitoes,  there  are  DDT 
foggings.  Against  fog,  filters  have  been  de- 
vised to  help  projectors  lay  the  picture  on 
the  screen  clearly  and  sharply. 

Hot  or  Cold — on  Order 

Though  the  weather  holds  most  ozoners 
down  to  a  30-week  season,  except  in  such 
places  as  California  and  Florida,  some  in- 
stall portable  electric  heaters  in  each  car. 
This  season  an  engineer  has  stepped  forward 
with  the  last  word — an  air-conditioning 
scheme  that  will  keep  the  cars  not  only  cozy 
against  wintry  blasts  but  cool  and  dry  in  the 
August  heat. 


What  projectionists  say  about  the 

ASHCRAFT  S^EM  LAMPS 


'They're    honies    .    .    / 


"Once  we  light  the  lamps 
they  take  care  of  them- 
selves." 


"The  lamps  are  the  pro- 
jectionist's dream." 


"We  trim  the  lamps  with 
our  bare  hands  ...  no 
tools." 


'We  have  yet  to  see  the  individual  who  does  not  like  the  lamp. 


TRULY    THE    PROJECTIONISTS'    PROJECTION    LAMP 


BOOTH  OF 
CRITERION 
THEATRE   IN 
THE  HEART  OF 
TIMES    SQUARE, 
NEW  YORK 


C.    S.    ASHCRAFT    MANUFACTURING    CO. 

36-32  Thirty-Eighth  Street,  Long  Island  City,  N.  Y. 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


29 


New  Graphecon  'Memory'  Tube 

Evidence  of  the  onward  rush  of  electronic 
development  is  a  new  electron  tube,  intro- 
ducing a  material  that  is  used  both  as  an 
electrical  conductor  and  an  insulator,  in 
which  the  fleeting  image  from  a  radar  scope 
can  be  retained  and  intensified.  The  tube,  de- 
veloped by  RCA,  is  a  "booster"  device  that 
is  employed  between  the  stage  where  the 
radar  beam  is  received  and  where  it  is 
reproduced  on  a  Tv  kinescope.  It  has 
"visual  memory,"  retaining  for  more  than 
a  minute  images  that  otherwise  would  have 
a  life  of  less  than  1/millionth  second. 

The  heart  of  the  Graphechon  is  a  metal 
target,  3  inches  square,  coated  on  one  side 
with  a  layer  of  pure  quartz  20/millionths 
inch  thick.  Two  beams  in  the  legs  of  a 
V-shaped  tube  are  aimed  at  this  target:  one 
is  the  radar  beam,  which  "writes"  on  the 
quartz  surface;  the  other  is  the  Iconoscope- 
type  beam — such  as  is  used  in  a    Tv  camera 


READING    G 


EVISION     DEFLECTION     YOKE 


— which  "reads"  from  it.  Unlike  a  fluores- 
cent screen,  the  target  is  not  light-sensitive, 
but  is  sensitive  to  electrical  charges. 

Action  of  the  'Reading'  Gun 

The  beam  of  electrons  from  the  "reading" 
gun  strikes  the  target  and  every  electron 
knocks  off  secondary  electrons,  which  fly  to 


"The  Projectionists'  Best  Friend!" 

$86.50  postpaid 

ARCON  MFG.  CO. 


^P 


•  Buzzes  when  light  is  going 
blue,  brown,  or  bad.  Works 
on  any  make  of  lamp.  One 
ARCON  watches  two  lamps. 
Full  instructions  and  1-year 
guarantee  with  order. 

Write  for  Folder. 


1214  WEST   30th  STREET 
LOS  ANGELES  7,  CALIF. 


nUJflRD  U1I1MER 

Flutter  Suppressor  Wins 
ACADEMY   AWARD! 


The  Academy  of  Motion  Picture  Arts  &  Sciences  recog- 
nized the  value  of  this  development  in  making  its  1947 
award  to  C.  C.  Davis  of  the  Western  Electric  Co. 

CENTURY  can  give  you  this  outstanding  improvement 
in  sound  reproduction   NOW. 


The  Award- 
winning  Hydro 
Flutter  Suppressor 
as  used  in  the 
new  Century 
sound  reproducer. 


Graphecon  "memory  tube," 
heart  of  which  is  a  metal 
target  3"  square  coated  on 
one  side  with  a  layer  of  pure 
quartz  20  millionths  of  an 
inch  thick.  Two  beams  in 
the  legs  of  the  V-shaped 
tube  are  aimed  at  this  target: 
the  radar  beam  "writes'' 
thereon,  while  the  other 
beam  (such  as  is  used  in  a 
Tv  camera)  "reads"  from  it. 


the  conductingi  coating  that  lines  the  tube. 
Removal  of  negative  electrons  builds  an 
increasing  positive  charge  on  the  target 
surface,  until  a  maximum  point  of  equilib- 
rium is  reached.  When  this  occurs,  the 
excess  of  secondary  electrons,  over  the  beam 
current,  returns  to  the  target,  maintaining 
the  electrical  status  quo.  At  this  point  the 
quartz  coating  is  acting  an  as  insulator  and 
permits  the  charging  of  the  surface  to  a 
higher  voltage   than   the   metal   sheet. 

At  this  point  the  Iconoscope  beam  has 
prepared  the  target  for  the  radar  beam. 
which  will  "write"  on  it.  When  the  radar 
receiver  picks  up  a  reflection,  the  signal 
turns  on  the  radar  beam  of  electrons  which 
crashes  through  the  quartz  layer,  makes  it 
conducting  at  that  point  and  there  dis- 
charges the  voltage. 

The  Iconoscope  scanning  beam  then 
knocks  secondary  electrons  from  that  spot 
on  the  target  in  an  effort  to  bring  it  back 
to  equilibrium.  This  removal  of  the  elec- 
trons produces  a  signal  on  the  target  which 
is  amplified  and  applied  to  the  kinescope. 
The  Iconoscope  scans  30  times  a  second  and 
can  take  as  long  as  2000  scans  to  bring 
the  signal  area  of  the  target  back  to  equilib- 
rium— or  read  off  the  signal  completely. 
Thus  the  image  may  be  retained  for  approxi- 
mately a  minute. 

On  the  other  hand,  the  radar  antenna 
revolves  once  every  five  seconds  and  repeats 
each  signal  at  that  interval.  By  coordinating 
the  reading  speed  of  the  Iconoscope  with 
the  writing  speed  of  the  radar  beam,  all 
the  signals  may  be  seen  on  the  kinescope 
with  a  high  level  of  brightness. 


Trust-Buster  Hits  Producer-Exhibs 

If  no  producer  were  permitted  to  profit 
from  theatre  operation,  the  number  of 
features  marketed  would  zoom,  former 
trust-buster  Thurman  Arnold  told  the 
House  Judiciary  Committee  recently. 
"The  trouble  is  .  .  .  that  they  put  out 
only  from  300  to  400  films  a  year  and  not 
enough  for  all  the  little  theatres  that  are 
desperately  going  broke  for  want  of  pic- 
tures and  setting  elaborate  schemes  as 
to  who  gets  this  short  supply,"  said 
Arnold. 

Thousands  of  films  would  profitably  be 
turned  out,  he  ventured,  if  no  producer 
were  permitted  to  hold  any  financial  in- 
terest in  theatres.  "Why  should  a  pro- 
ducer make  a  lot  of  pictures  for  his  com- 
petitors?" he  concluded.  "It  can  make 
more  money  out  of  that  set-up  by  re- 
ducing the  supply." 


30 


INTERNATIONAL   PROJECTIONIST 


September    1949 


NEWS     PROJECTIONS 

Jottings  of  happenings  which,  while  mostly  of 

a  non-technical  nature,  have  a  bearing   upon 

general  industry   welfare  and  progress. 

SETTLED  policy  of  both  AF  of  L  and 
the  CIO  to  bear  down  on  seniority 
protection  and  pension-welfare  plans  in 
lieu  of  wage  increases  is  expected  to 
be  reflected  in  future  film  industry  bar- 
gaining. .  .  .  20th-Fox  and  Warners 
still  wrestling  with  Dept.  of  Justice 
about  theatre  divestiture  formula.  .  .  . 
Congressional  leaders  adamant  in  re- 
fusing to  accede  to  flood  of  requests 
for  repeal  or  reduction  in  20%  ticket 
tax.  .  .  .  FCC  shows  no  sign  of  relent- 
ing in  its  tough  attitude  toward  appli- 
cation for  Tv  licenses  from  film  com- 
panies hit  by  anti-trust  decrees. 

By  the  end  of  1950  A.  T.  &  T.  Tv  net- 
work will  cover  43  cities.  Company  told 
the  FCC  that  experiments  have  demon- 
strated that  both  coaxial  cable  and 
radio  relay  can  transmit  color  Tv.  .  .  . 
Western  Union  wants  in  on  the  Tv  pic- 
ture via  its  relay  equipment  now  being 
used  for  telegraphic  messages.  W.  U. 
qualifies  as  a  "common  carrier"  under 
the  communications  law.  .  .  .  FCC  ban 
of  all  giveaways  on  the  radio  networks 
cheered  theatre  interests.  Broadcasters 
will  fight  ban  in  courts.  .  .  .  Deny  it  or 
not,  fact  is  that  distribs  have  slashed 
number  of  release  prints  over  the  coun- 
try. Bum  prints  the  inevitable  result, 
especially  since  little  time  is  afforded 
for  interim  inspection.  .  .  .  Kicks 
against  non-advertised  reissue  films 
mounting  all  over  the  country.  Movie- 
goer doesn't  find  out  the  score  until  he's 
paid  his  dough  and  sat  thru  a  reel  or  so. 


Columbia  will  release  67  films  next 
season,  including  31  "top"  production, 
22  "features"  (how  much  off  from  the 
"top"  is  not  stated)  and  about  15  west- 
erns. .  .  .  Distributors  fear  theatres 
will  be  drawn  into  a  giveaway  rat  race 
as  an  antidote  to  mild  b.o.  fare  and 
competition  from  other  amusements. 
Premiums  more  widespread  than  ever. 


.  .  .  American  film  circles  still  dazed 
by  savage  attack  by  Tom  O'Brien,  Brit- 
ish Labor  leader  and  M.P.,  on  the  "al- 
mighty dollar  mentality  of  America" 
and  the  'unlettered,  potbellied  money 
magnates  of  the  U.S."  O'Brien  at- 
tended the  LA.  convention  in  1948. 

Rev.  Patrick  Masterson,  executive 
secretary  of  Catholic  Legion  of  De- 
cency, says  pictures  are  at  an  all-time 
moral  low.  The  padre's  chief  blasts 
were  at  foreign  imports.  .  .  .  Shooting 
time  on  Hollywood  sets  has  been  cut 
25%,  reports  the  Wall  Street  Journal. 
Pre-shooting  preparation  is  said  to  be 
main  factor  in  cut.  .  .  .  Warner  Bros, 
backlog  of  completed  films  now  total  59. 
.  .  .  More  and  more  American  producers 
getting  set  for  foreign  production  in 
order  to  siphon  off  blocked  funds. 
Tough  on  Hollywood  technicians.  .  .  . 
Technicolor,  facing  an  anti-trust  suit, 
offers  to  license  any  other  company  on 
"appropriate  terms."  .  .  .  All-industry 
conference  on  public  relations  in  Chi- 
cago on  Sept.  1  developed  into  a  love 
feast. 

Altec-Lansing  entry  in  Tv  receiver 
field  strictly  a  tailor-made  proposition. 
.  .  .  Paramount  earnings  for  second 
1949  quarter  ending  July  2  were  $7,- 
800,000  as  compared  with  $5,810,000 
for  like  period  last  year.  Special  non- 
recurring 1949  income  of  $4,500,000 
arose  chiefly  from  sale  of  theatres  and 
other  joint  interests  as  required  by  the 
consent  decree. 


Definitely  new  is  the  new  plan  to  ex- 
tend credit  to  moviegoers  in  heavily  in- 
dustrialized areas  which  have  been  hit 
by  strikes.  Books  containing  40  ex- 
change tickets  are  issued  upon  submis- 
sion of  an  auto  driver's  license,  a  car 
owner's  registration  or  a  Social  Secur- 
ity card.  No  checkups  will  be  made,  no 
bills  issued,  the  patron  being  expected 
to  pay  as  soon  as  possible  at  regular 
box  office  scales.  The  theatre  will  ad- 
vance the  Federal  tax  on  each  "charge 
it"  admission.  .  .  .  The  anti-trust  decree 
forcing  the  divestiture  of  many  chain 
theatres  will  "open  up"  towns  hereto- 
fore closed  to  any  but  producer-dis- 
tributor houses. 


®®t?*f\  SINCE  THAT  DRIVE-H1  PUT  IN 
SUPER-LITES,  NOTHING  EVER  PASSES  HERE/ 


FOR     EDGE-TO-EDGE     DEFINITION 

THINK    OF    SUPER-LITE 

With  speeds  of/1.6  to/l.9,  in  suitable  focal  lengths  for  most 

Drive-ins    and    Theaters,    SUPER-LITE    lenses    assure    you    of 

superior   performance. 

SEE    US    AT    BOOTH    78,    THE    CHICAGO    T.  E.  S.  M.  A.   CONVENTION 

*Pwkcti<M  O fitter 

'  COMPANY,  INC. 

OPTICS  SUPPLIER  TO  THE  LEADING   PROJECTOR  MANUFACTURERS 
332      LYEIL      A  V  E  N  U  E    .    R  O  C  H  E  S  T  E  R      6,     NEW      YORK,     U.S.A. 


HARRY  L.  NACE,  SR.— President, 
Harry  L.  Nace  Theatres,  Inc.,  Phoe- 
nix, Arizona — says: 

"Sound  is  the  very  heart  of 

our  theatres  .  .  .  and  RCA 

Service  is  the  very  heart  of 

our  sound." 

To  get  the  benefits  of  RCA  Service — 

write:   RCA  SERVICE   COMPANY, 

INC. .Radio  Corporation  of  America, 

Camden,  N.  J. 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


31 


Du  Pont's  New  Polymer  Color  Release  Positive  Film 


PRODUCTION  of  a  release  positive 
color  film  replacing  gelatin  with  a 
superior  synthetic  polymer  has  been  an- 
nounced by  Du  Pont.  The  film  is  suit- 
able for  making  color  prints  in  the  pro- 
fessional motion  picture  field.  It  is  de- 
signed to  be  printed  from  three  black- 
and-white  separation  negatives  and  to 
be  developed  in  color  during  a  single- 
passage  through  a  slightly  modified 
conventional    developing    machine. 

The  film  consists  of  three  emulsion 
layers  superimposed  on  one  side  of  stand- 
ard cine  film  base.  The  binder  ior  each 
layer  is  a  polymer  which  behaves  also  as 
a   dye  intermediate  capable  of  forming 


onci 


V 


cJLife  Lji 


uaruniee 


teed 


]  G-83 


Precision  designed,  ruggedly 
constructed,  factory  "aged" 
and  thoroughly  tested  f  o» 

SMOOTH    OPERATION 

CONSTANT    POWER    SUPPLY 

LONG   LIFE 

Guaranteed  for  1,200  op- 
erating hours  when  used 
at    their     proper     rating. 


See  our  exhibit  at  the 
TESMA  Trade  Show, 
Sept.  26-28,  Stevens 
Hotel,  Chicago,   Illinois. 


ASK   YOUR    DEALER 
— HE   KNOWS 


GORDOS   CORPORATION 

86   SHIPMAN   STREET      •      NEWARK  2,  N.  J. 


a  dye  image  under  the  control  of  a  de- 
veloping silver  image,  according  to  the 
well-known  method  of  color-forming  de- 
velopment. 

Procedural  Changes  Effected 

In  the  past,  the  emulsion  layers  for 
color-forming  development  have  con- 
tained at  least  three  components — gela- 
tin, silver  halide,  and  color-former.  In 
the  printing  film  worked  out  by  Du  Pont, 
only  two  components  are  employed — sil- 
ver halide  and  a  water-sensitive  synthetic 
polymer  which  plays  the  role  of  both 
gelatin  and  color-former. 

Heretofore,  it  has  been  considered 
that  a  slightly  solubility  of  the  color- 
former  in  water  was  essential  in  order 
to  bring  about  the  dye-coupling  reaction 
and  that  the  migration  of  a  soluble  color 
former  had  to  be  prevented  by  various 
means.    ■ 

In  the  new  conception  developed  by 
Du  Pont,  there  are  no  problems  of  mi- 
gration or  solubility.  The  color-former 
is  as  insoluble  as  gelatin.  Water  only 
swells  it.  When  the  polymer  is  swollen 
by  processing  solutions,  the  color-form- 
ing groups,  though  bound  up  in  a  com- 
plex polymer  molecule,  remain  highly 
reactive  with  the  oxidation  product  of 
the  developer. 

Layer  Arrangement  in  New  Film 

The  layer  arrangement  in  Du  Pont 
color  print  stock  departs  from  the  order 
usually  used  by  monopcak  producers.  It 
is  as  follows: 

Blue-sensitive 

emulsion    magenta  polymer 

Red-sensitive 

emulsion   cyan 

Green-sensitive 

emulsion    yellow 

Support 

This  arrangement  is  permissible  be- 
cause the  printing  is  done  on  a  registra- 
tion printer  and  any  one  of  the  three 
separation  negatives  can  be  directed  into 
the  appropriate  layer  by  the  proper  selec- 
tion   of    printing    light.    The    particular 


w> 
m 

WUkSk 


UNBREAKABLE 

Non-Pitting 

H 


GUARANTEED  5  YEARS 


Manufactured  by 

HEYER-SHULTZ,  INC. 
CEDAR  CROVE,  N.  I. 


/  <  I  »I\A 


Oirtributod  Exclusively  by 

( JJ*T.I~—  *£L) 


arrangement  aforementioned  permits 
optimum  quality  in  that  the  most  im- 
portant records  from  the  standpoint  of 
definition  are  placed  in  the  top  layers, 
and  the  yellow,  least  important,  is  placed 
in  the  bottom  layer  where  diffusion  effects 
caused  by  printing  through  the  two  em- 
ulsion layers  are  least  noticeable. 

The  layer  arrangement  invites  the  use 
of  a  dye  sound  track  and  a  blue-sensitive 
photocell  for  reproducing  sound.  A 
track  in  magenta,  which  gives  good  re- 
sponse to  a  blue  cell,  can  be  confined  to 
the  outer  layer  to  get  the  advantage  of 
sharp  definition.  But  since  blue  cells  are 
not  a  part  of  present  theatre  equipment, 
a  silver-plus  dye  track  is  recommended. 
This  can  be  obtained  by  several  known 
methods,  such  as  preventing  the  bleach- 
ing of  the  sound  area  or  by  redeveloping 
or  sulfiding  the  track  after  bleach. 

The  polymer  film,  although  yielding 
acceptable  results  with  separation  nega- 
tives made  from  a  color  original,  will  give 
maximum  quality  with  black-and-white 
separations  made  in  a  split-beam  beam 
camera  or  by  other  means  capable  of  giv- 
ing black-and-white  originals. 

Clarify  in  Circuit  Diagrams 

With  the  increasing  use  of  electronic 
apparatus  in  industry  and  engineering,  sym- 
bols which  were  originally  only  intelligible 
to  the  radio  circuit  designer  are  now  ap- 
pearing in  all  the  technical  journals,  and 
engineers  find  that  their  present-day  knowl- 
edge has  to  include  an  ability  to  read  the 
complexities  of  an  electronic-circuit  diagram. 

This  task  is  not  made  easier  when  the 
circuit  diagram  takes  on  a  variety  of  forms 
and  contains  an  assortment  of  symbols  which 
differ  sometimes  from  page  to  page  in  a 
given    publication.      It    is    unfortunate    thai 


IKE   BERNEY,    Owner,   and   son 
IRV  BERNEY,  Manager— Pastime 
Theatre,  Lewiston,  Pa. — say: 
"RCA  Service  is  tops  in  our 
opinion.  We  never  have  un- 
expected repair  and  replace- 
ment. Promptness  seems  to 
be  RCA's  watchword." 
To  get  the  benefits  of  RCA  Service — 
write:    RCA   SERVICE    COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


32 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


these  symbols  differ  even  between  branches 
of  the  same   profession. 

For  example,  the  power  engineer's  trans- 
former, sometimes  represented  by  a  pair  of 
wavy  lines,  becomes  the  radio  engineer's 
resistance.  The  non-inductive  resistance  in 
electronic  diagrams  is  commonly  used  for 
an  ordinary  resistance  in  power  circuits. 

To  add  to  the  difficulties  of  reading,  some 
circuits  are  drawn  in  such  a  manner  that 
only  an  expert,  with  a  pencil  laboriously 
tracing  over  the  lines,  can  determine  the 
function  of  each  component.  His  work  is 
made  still  harder  if  unfamiliar  outlines  are 
used  to  identify  familiar  components. 

As  was  stated  in  a  recent  article:  "The 
object  of  a  circuit  diagram  is  the  explana- 
tion of  the  operation  of  a  given  circuit,  and 
any  attempt  to  make  the  diagram  fulfil  the 
additional  role  of  a  wiring  diagram  usually 
results  in  obscuring  the  electrical  operation 
of  the  circuit." 

The  use  of  graphical  symbols  familiar  to 
all  and  accepted  as  standard  will  obviously 
simplify  the  task  of  reading  a  complex 
circuit.  The  introduction  of  universal  elec- 
trical graphical  and  letter  symbols  is  an 
important  step  toward  that  standardization 
to  which  we  all  pay  lip-service  but  seldom 
encourage. — Electronic    Engineering. 


Soldering  a  Wire  to  a  Crystal 

How  would  you  solder  a  wire  to  a  crystal? 
This  must  be  done  for  most  of  those  wafer- 
thin  plates  of  quartz  used  in  electrical 
circuits.  They  play  a  big  part  in  the  myriad- 
channel  telephone  system  that  utilizes  co- 
axial cables. 

This  is  how  Bell  Labs  solved  the  problem : 
a  spot  of  paste  containing  silver  is  deposited 
on  the  crystal  and  bonded  to  it  by  oven 
heat.  The  crystal  is  then  vapor-plated  with 
a  thin  layer  of  silver.  Then  a  fine  wire  is 
soldered  to  the  spot  by  a  concentrated  blast 
of  hot  air.  The  result  is  a  rugged  electrical 
connection  to  the  surface  of  the  crystal  which 


E.  O.  BRILES— Owner  and  Man- 
ager, Lyric  Theatre,  Emporia,  Kan- 
sas— writes: 

"RCA  Service,  over  a  period 
of  15  years,  has  proved  its 
value  to  us  in  consistently  good 
sound  quality  and  trouble-free 
operation.  We  are  'RCA  All 
The  Way.' " 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


does  not  interfere  with  its  vibrations. 

Sealed  in  glass  tubes,  the  crystals  are 
precise  and  reliable  performers  in  com- 
munications. Each  is  a  crystal  gate  to  a 
voiceway,  separating  your  conversation  from 
the  hundreds  of  others  which  may  be  using 
a  pair  of  coaxial  conductors,  at  the  same 
time.  ^_^__^_^_^_ 

Projection  Optics  Reorganization 

The  reorganization  of  Projection  Op- 
tics Co.,  of  Rochester,  N.  Y.,  is  now 
complete,  according  to  an  anouncement 
by  Fred  E.  Aufhauser,  president.  Fran- 
cis J.  Fouquet  is  vice-president  in  charge 
of  manufacturing.  Present  plans  of  the 
company  include  a  widening  and  im- 
provement of  service  and  an  addition  to 
the  Superlite  series  of  lenses. 


BOOK     REVIEW 

The  Complete  Projectionist,  by  Howard 
Cricks,  F.B.K.S.,  F.R.P.S.  Fourth  edition, 
edited  by  Alex  J.  Martin.  374  pages,  more 
than  200  illustrations,  3  blueprints  and  in- 
dex. Blue  leather  cloth.  Odhams  Press, 
Ltd.,  6  Catherine  St.,  London,  W.C.  2.  10/- 
{approx.  $2.50  U.S.). 

This  work  produced  in  England,  is  a 
general  handbook  for  projectionists.  The  33 
chapters  cover  every  conceivable  phase  of 
projection  theory  and  practice  in  a  compre- 
hensive, well-balanced  manner.  Television 
and  experimental  developments  are  given  a 
proportionate  share  of  space,  and  the  numer- 
ous tables,  charts,  and  projection  rules  and 
regulations  (British)  are  only  a  few  features 
which  make  this  book  a  giveaway  at  its 
modest   price. 

Mr.  Cricks,  technical  editor  of  Ideal  Kin- 
ema  (London)  and  not  unknown  to  readers 
of  IP,  has  produced  a  compendium  which 
should  commend  itself  highly  to  projection- 
ists everywhere.  Concise  and  lucid,  this 
book  is  eminently  practical  and  informative; 
and  apart  from  a  few  points  on  which  we 
differ  with  the  author  (the  handling  of  film 
fires  and  the  cleaning  of  lenses,  for  ex- 
ample), the  work  is  technically  accurate  and 
wholly  trustworthy.  The  concise  presentation 
of  basic  optical,  acoustic  and  electrical  prin- 
ciples set  a  standard  for  projection  texts. 

There  is  a  remarkably  good  exposition  of 
the  high-intensity  arc,  and  the  treatment  of 
the  value  of  the  arc  voltage  (not  generator 
or  rectifier  voltage)    as  an  indicator  of  arc 


stability  is  thought-stimulating.  Also  ac- 
corded first-rate  treatment  are  projection 
room  appointments,  oil  and  gas  engines, 
studio  process  projection,  stereophony,  stere- 
oscopy,  color  films,  and  16-mm  projection. 
The  section  on  sound  is  fully  abreast  of 
latest  developments.  The  book  is  beautifully 
printed  and  illustrated. 

The  understandable  preoccupation  with 
British  equipments  and  practice  does  not 
limit  the  usefulness  of  this  book,  and  com- 
parisons made  to  evaluate  the  worth  of  this 
volume  need  not  be  confined  to  the  European 
field.  Indeed,  those  American  projectionists 
who  have  found  considerable  fault  with  the 
unwieldly  and  error-sated  American  manu- 
als on  the  art  will  find  "The  Complete  Pro- 
jectionist"' a  long-sought  medium.  Highly 
recommended. — R.A.M. 


for 

SMOOTH 
DEPENDABLE 
D.  C.  Power  Supply 


CLAYTON  BALL-BEARING 

EVEN  TENSION  TAKE-UPS 
For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reels. 
Silent  Chain   Drives 

THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reek. 

CLAYTON    PRODUCTS    CO. 

31-45  Tibbett  Avenue  New  York  63,  N.  Y. 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


33 


COOLING    MEANS    FOR    H-l    ARC 
PROJECTION 

{Continued  from  page  25) 

success  in  indoor  theatres,  despite  the  attendant  reduction 
in  light  transmission.  This  set-up  has  been  found  wanting 
in  outdoor  theatres,  however,  where  every  last  lumen  is 
needed  to  project  an  acceptable  picture. 

We  have  not  thoroughly  tested  the  idea  of  water-cooling 
the  aperture,  thus  we  cannot  make  any  positive  statements 
about  it.  It  is  our  impression,  however,  that  most  of  the 
heat  imparted  to  the  film  is  due  to  the  direct  rays  from 
the  lamp  rather  than  from  contact  with  the  metal  parts 
adjacent  to  the  film.  Temperatures  of  up  to  200 °F  are 
conducted  to  these  surrounding  metal  parts;  while  the 
temperature  in  the  direct  light  may  exceed  1000°F.  Thus 
while  water-cooling  the  aperture  parts  may  save  the  pro- 
jectionist some  discomfort,  it  seems  to  us  that  its  effect 
upon  the  film  is  decidedly  limited. 

The  air-jet  principle  appears  to  be  the  best  solution  to 
this  problem.  We  have  not  yet  completed  our  investiga- 
tion as  to  the  degree  of  temperature  reduction  on  the  film 
effected  by  this  means,  but  with  the  use  of  a  blower  ar- 
rangement we  have  reduced  the  temperature  of  the  aperture 
casting  by  as  much  as  40%.  In  addition  to  the  indirect 
cooling  effect  this  has  on  .the  film,  the  air-jet  principle 
permits  what  is  probably  a  far  more  effective  action 
directly  on  the  film. 

While  we  don't  believe  that  it  is  the  function  of  the 
Society  of  Motion  Picture  Engineers  to  resolve  differences 
of  opinion  of  this  nature  among  manufacturers,  it  is  en- 
tirely possible  that  an  SMPE-sponsored  investigation  of 
this  problem  might  result  in  a  solution  somewhat  faster 
than  would  be  otherwise  possible. 

By  HARRY  STRONG 
President,  Strong  Electric  Corp. 

THE  problem  of  preventing  film  damage  due  to  heat  at 
■  the  aperture  is  like  the  poor — it  has  always  been  with 
us.  Since  the  beginning  of  the  motion  picture  business 
there  has  been  a  constant  demand  for  more  light  at  the 
screen,  and  the  constant  increasing  of  this  light  has  re- 
sulted in  more  energy  at  the  aperture,  more  possibility  of 
film  damage,  and  repetitions  of  temporary  hysteria  in  the 
equipment  business.  But  each  time  that  a  new  source  of 
increased  light  has  been  introduced,  there  has  been  found 
a  satisfactory  means  of  avoiding  resultant  film  damage. 

Many  will  recall  that  when  we  went  from  the  straight 
arc  to  the  low-intensity,  everybody  was  worried  about 
increased  fire  hazards.   Better  projector  design  solved  that. 


When  we  went  from  the  low-intensity  to  the  high-intensity 
arc  a  decade  ago,  there  was  a  temporary  wave  of  com- 
plaints from  film  exchanges  because  of  print  damage. 
This  was  adequately  eliminated  by  adoption  of  the  rear 
shutter,  in  preference  to  the  front  shutter,  with  an  attend- 
ant reduction  of  50%  in  the  radiant  energy  at  the  film 
aperture,  and  without  reducing  the  picture  brilliancy. 

With  the  transition  from  silent  to  sound  pictures  we 
thought  that  things  were  looking  up,  for  the  increase  in 
film  speed  from  16  to  24  frames  per  second  reduced  the 
time  any  one  frame  was  exposed  to  the  heat.  But  with  the 
addition  of  the  sound  track  to  the  film  the  size  of  the 
picture  aperture  was  reduced,  so  that  in  order  to  project 
the  same  amount  of  light  to  the  screen  the  energy  per  unit 
of  film  area  was  necessarily  increased,  which  in  turn  again 
aggravated  the  film  buckling  problem. 

Print  Density  an  Important  Damage  Factor 

Subsequently,  to  the  end  of  improving  the  photographic 
quality  of  the  picture  at  the  screen,  producers  began 
developing  their  prints  to  greater  densities.  Since  the 
radiant  energy  from  the  lamp  either  passes  through  the 
film  to  the  screen  as  light  energy,  or  is  retarded  in  pro- 
portion to  the  density  of  the:  film  and  converted  into  heat 
energy  within  the  film,  these  new  prints  were  more  sus- 
ceptible to  damage  than  the  earlier  thin  prints. 

And  so  the  ever  increasing  quest  for  more  light  to 
adequately  illuminate  the  modern  screen  has  continually 
been  linked  with  film  damage  possibilities  in  direct  pro- 
portion to  the  increase  in  light  volume. 

Current  lamps  which  have  been  manufactured  for  the 
past  several  years  have  been  capable  of  consistently  pro- 
jecting the  maximum  light  that  the  film  would  accept 
without  damage  and  without  the  use  of  cooling  devices, 
and  they  deliver  all  the  light  that  was  necessary  for  the 
majority  of  the  screens. 

The  advent  of  tremendous  size  screens,  especially  in 
drive-in  theatres,  has  again  today  brought  demands  for 
still  more  light.  These  demands  have  resulted  in  the  de- 
velopment of  higher  powered  arcs  which,  if  operated  at 
their  capacity,  will  provide  the  necessary  increase  in  light. 
Simultaneously,  increased  energy  at  the  film  aperture  has 
reintroduced  the  problem  of  permanent  film  damage,  or 
has  at  least  resulted  in  buckling  that  causes  the  film  to 
move  laterally  both  toward  and  also  away  from  the  pro- 
jection lens,  making  it  difficult,  if  not  impossible,  to  keep 
the  screen  image  in  focus. 

So  once  more  the  old  bugbear,  film  damage,  is  with  us. 
In  the  few  cases  where  the  maximum  capacity  of  the  lamp 
is  required,  however,  the  currently  available  methods  or 
devices  for  removing  some  of  the  energy  in  the  longer 
wave  region  have  adequately  solved  the  problem. 


Research  and  Development  in  Applied 
Optics  and  Optical  Glass  at  the  National 
Bureau  of  Standards  (Miscellaneous  Pub- 
lication M-194)  ;  by  Irvine  G.  Gardner  and 
C.  H.  Hahner;  20  large  double-column  pages, 
16  illustrations,  complete  bibliography  of 
195  publications;  15c  per  copy  from  the 
Superintendent  of  Documents.  U.  S.  Govern- 
ment Printing  Office,  Washington  25,  D.  C. 
Remittances  must  be  in  U.  S.  exchange  and, 
from    foreign     countries,    must    include    an 


additional  sum  of  1/3  the  publication  price 
to  cover  mailing. 

The  National  Bureau  of  Standards  is  the 
only  scientific  institution  in  the  world  which 
has  complete  facilities  entirely  within  its 
own  organization  for  making  an  optical  in- 
strument, beginning  with  the  raw  materials 
and  in  turn  producing;  the  glass,  the  optical 
design,  the  lenses  and  prisms,  the  mechani- 
cal parts,  and  finally  the  finished  instrument. 
Since  its  founding  in  1901,  the  Bureau  has 


conducted   a   broad   program   of   optical   re- 
search and  development. 

This  work  has  included  the  development 
of  technological  processes  for  the  production 
of  optical  glass,  the  study  of  the  properties 
of  optical  materials,  the  maintenance  of 
optical  standards,  the  design  of  lenses  and 
optical  systems,  the  production  of  prototype 
optical  instruments,  the  determination  of 
performance  characteristics,  the  devising  of 
methods  for  testing  and  calibration,  the 
preparation  of  specifications,  and  a  complete 
consultant  service. 


34 


INTERNATIONAL    PROJECTIONIST     •     September    1949 


SO  MUCH 


for  so  LITTLE 


$0.00 


3 


per  copy 
pottage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores oi  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  far  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


S&nd  #0/1  jH  Vbwi 


/ 


(Do  Tboi  (Dslay 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18.  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a  copy  oi  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
Name  _ _» 


Address 
City    


Stale 


V 


;*N 


Njrtffl 


PROJECTION  &  SOUND 
FOR  DRIVE-IN  THEATRES 


MANUFACTURED    BY    INTERNATIONAL    PROJECTOR    CORPORATION     •     BIOOIHIFIEID,    NEW    JERSEY 


~7m 


OCTOBER 


1949 


VOLUME  24       •       NUMBER   10 


30c  A  COPY    •    S2.50  A  YEAR 


\ 


•_ _  ?         $Tir? 


'""^ 


This  is  how  Chic  Young,  the  cartoonist,  makes  a  first  rough  sketch  for  the  famous  strip. 


Then  when  each  panel  in  a  strip  meets  his  approval,  he  makes  a  careful  pencil  rendering  as  above. 


JOIN  THE  PAYROLL  SAVINGS, 
PLAN  ANP  WE'LL  6ET"*4.22 
FOR  EVERV*3.2?  IN  JUST 
TEN  YEARS.1 


After  this,  the  pencil  rendering  is  carefully  inked  in,  as  you  see  here. 


STEP  BY  STEP... 

that's  the  way  it's  done  successfully! 


as  you  can  see,  Chic  Young,  who  draws 
■**■  the  popular  "Blondie"  comic  strip, 
goes  through  many  steps  to  arrive  at  a 
finished  cartoon. 

And,  cartoonist  Chic  Young,  together 
with  millions  of  other  smart  Americans, 
will  tell  you  that  the  step- by-step  method 
is  the  easiest,  surest  way  of  doing  any- 
thing worth  while. 

Particularly,  saving  money. 

One  of  the  easiest  and  surest  ways  to 


set  aside  any  worth  while  amount  of 
money  is  to  buy  United  States  Savings 
Bonds  the  step-by-step  method — 

So  set  aside  a  regular  amount  week  after 
week,  month  after  month,  year  after  year. 
Then  in  10  short  years  you  will  have  a 
mighty  nice  nest  egg  tucked  away  for  you 
and  your  family. 

Get  started  now.  Get  your  Bonds  through 
Payroll  Savings  or  at  your  bank  or 
post  office. 


AUTOMATIC  SAVING  IS  SURE  SAVING— U.S.  SAVINGS  BONDS 


Contributed  by  this  magazine  in  co-operation  with  the  Magazine  Publishers  of  America  as  a  public  service. 


©c 


IB    216141 


OCT  2i  19 W 


INTERNATIONAL 

PROJECTIONISl 

With  Which  Is  Combined  Projection  Engineering 


HENRY  B.   SELL  WOOD,  Editor 


Volume  24                                  OCTOBER4949                                 Number 

10 

Index  and  Monthly  Chat 

Roundup:    'Matched'  Projection 

3 
5 

Strong's    New    'Mighty   90'    75- 
125  Amp.  Reflector-Type  Pro- 
jection Arc 

15 

Optics    

A.  E.  Neumer 

Dr.  J.  L.  Maulbetsch 

Robert  A.  Mitchell 

Questions  and  Answers  on  Pro- 
jection  Lenses 

16 

Improved  Concentrated-Arc 

10 

Telecasts 

17 

Fire  Extinguishers  in  Projection 
Rooms 

12 

In   the   Spotlight 
Harry  Sherman 

18 

George  A.  Stewart 
Robert  A.  Mitchell 

DeVry's  'Koolite'  Unit  for  H-I 
Arcs     

14 

The  Origins  of  the  'Magic  Lan- 
tern,' II   . 
J.  Voskuil 

21 

E.  W.  D'Arcy 

News  Notes 

The   Starke   Cycloramic   Projec- 
tion Screen   

14 

Technical  Hints 
Miscellaneous  Items 

Herbert  A.  Starke 

Published  Monthly  by 
INTERNATIONAL   PROJECTIONIST   PUBLISHING    CO..    INC. 

19  West  44  Street,  New  York  18,  N.  Y. 

R.  A.  ENTRACHT,  Publisher 
SUBSCRIPTION  REPRESENTATIVES 

AUSTRALIA:  McGills,  183  Elizabeth  St.,  Melbourne 

NEW  ZEALAND:    Te  Aro   Book  Depot,  Ltd.,  64  Courtenay  Place,  Wellington 

ENGLAND  and  DOMINIONS:  Wm.  Dawson  &  Sons,  Ltd.,  Macklin  St.,  London,  W.  C.  2 


Yearly  Subscription:  United  States  and  possessions,  $2.50  (two  years,  $4) ;  Canada  and 
foreign  countries,  $3;  single  copies,  30  cents.  Changes  of  address  should  be  submitted 
two  weeks  in  advance  of  publication  date  to  insure  receipt  of  current  issue.  Entered  as 
second  class  matter  February  8,  1932,  at  the  Post  Office  at  New  York,  N.  Y.,  under  the 
act  of  March  3,  1879.  Entire  contents  copyrighted  T949  by  International  Projectionist ' 
Publishing  Co.,  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


420 


MONTHLY   CHAT 


REPERCUSSIONS  of  the  symposium 
on  cooling  methods  for  high-inten- 
sity arcs  which  was  published  in  these 
columns  last  month  continue  to  manifest 
themselves  in  IP's  mailbag.  As  was  to  be 
expected,  IP  readers  are  more  than  a 
little  perplexed  at  the  sharp  differences 
of  opinion  evident  in  the  statements  by 
the  various  equipment  manufacturers,  no 
less  than  they  are  disappointed  at  the 
obvious  lack  of  forthrightness  among 
some   of  the  contributors. 

IP  readers  in  general  wonder  why  it  is 
impossible  to  take  the  direct  approach  to 
a  technical  problem,  such  as  this  one 
anent  cooling,  and  on  the  basis  of  ex- 
periment and  test  come  up  with  the  cor- 
rect answer — one  answer.  Instead,  we 
were  treated  to  almost  as  many  different 
opinions  as  there  were  contributors,  a 
performance  indicative  of  something  less 
than  a  sincere  desire  on  the  part  of  the 
manufacturers  to  service  their  customers 
properly  by  a  forthright  approach  to  this 
problem. 

We  may  expect  to  see  the  lamp  manu- 
facturers going  on  their  respective  ways 
by  water-cooling  the  carbons,  the  while 
they  ignore  the  problems  of  the  projector 
manufacturers;  the  latter  will  probably 
continue  to  utilize  one  of  three  possible 
methods — glass  filters,  air  blast,  or  water- 
cooled  apertures — to  minimize,  but  not 
eliminate,  a  definite  defect  of  the  pro- 
jection process. 

IP  is  not  happy  about  the  outcome  of 
this  abortive  effort  to  effect  some  sort  of 
general  agreement  on  this  problem 
among  the  various  manufacturers,  but  it 
is  glad  to  have  been  able  to  provide  the 
means  for  focusing  craft-wide  attention 
upon  the  topic.  Ultimately,  and  not  too 
far  away,  the  manufacturers  of  both  arc- 
lamps  and  projectors  will  have  to  square 
up  to  this  matter — and  then  it  will  be 
much  more  difficult  because  the  fellow 
whom  they  will  meet  face-to-face  will  be 
the  purchaser  of  their  equipments. 

The  mixed  reaction  evoked  among  film 
people  by  the  recent  showings  of  the 
World  Series  ball  games  via  television 
in  various  theatres  does  not  indicate  that 
this  process  is  a  dead  horse  in  an  eco- 
nomic sense.  Far  from  it.  The  Series 
was  on  view  in  practically  every  tavern 
in  the  Eastern  states.  The  real  test  will 
come  when  there  exist  sufficient  theatres 
Tv-equipped  to  warrant  showings  in 
movie  houses  exclusively. 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


/ 


In  Projectors  .  •  • 


Automatic  Lubrication 


* 


■V-S'1- 


FOR  SMOOTH,  HIGH  QUALITY  PERFORMANCE 


YOU  need  look  no  further  than  the  automatic 
lubrication  system  of  Brenkert  Projectors 
to  find  reasons  for  Brenkert's  dependable  per- 
formance in  drive-in  and  indoor  theatres. 

A  continuous  stream  of  oil  is  automatically 
showered  over  gears,  shafts,  bearings — all  mov- 
ing parts.  Brenkert's  oiling  system  eliminates 
friction.  Frictionless  operation  means  wear  is 
negligible  even  after  many  years  of  operation. 

Oil  circulating  continuously  acts  as  a  cooling 
system  as  well  as  a  lubrication  system.  This  is 
important  in  drive-ins  where  high  amperage 
arcs  cause  intense  heat. 


With  Brenkert's  dustproof  gear  cover  the 
oil  is  kept  inside;  dust,  lint  or  foreign  matter 
is  kept  out. 

Longer  wearing  of  all  parts.  No  worry  about 
bind-ups.  Automatic  lubrication  is  one  of  many 
reasons  why  Brenkert  Projectors  do  a  better,  a 
more  efficient  job  of  providing  the  finest  per- 
formance in  motion  picture  projection,  over  a 
longer  period  of  time. 

Write  Dept.  47J,  for 
FREE  booklets  on 
Brenkert  "80"  and 
"60"  Projectors. 


YOUR  INDEPENDENT  RCA  THEATRE  SUPPLY  DEALER 
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In  Canada:  RCA  VICTOR  Company  Limited,  Montreal 


VOLUME  XXIV 


OCTOBER  1949 


NUMBER  10 


Roundup:   Matched'  Projection  Optics 


To  the  Editor  of  IP: 

Reference  is  made  to  the  article  on  the  match- 
ing of  projection  optics  by  Mr.  R.  A.  Mitchell 
in  the  March  1949  issue  of  your  publication.* 
and  also  to  the  subsequent  comments  on  the  same 
topic  in  both  the  Mayf  and  JuneJ  issues.  We- 
have  read  all  of  these  with  a  good  deal  of  inter- 
est, but  we  are  somewhat  puzzled  by  the  fact 
that  no  one  has  challenged  Mr.  Mitchell's  deriva- 
tion of  his  general  formula  for  matching  (shown 
as  Fig.  4,  page  9,  in  IP  for  March;  as  Fig.  1  in 
this  issue)  and  also  the  simplified  formula  which 
is  based  on  the  fact  that  the  diagonal  of  the  sound 
film  aperture  is  approximately  one  inch. 

Not  only  have  we  been  unable  to  derive  the 


basic  general  formula  exactly  as  it  appears  (Fig. 
1)  but  neither  have  we  been  able  to  see  how  the 
simplified  form  is  arrived  at  after  the  aforemen- 
tioned assumption.  It  is  entirely  possible  that  we 
have  overlooked  some  obvious  points,  or,  as  we 
first  suspected,  that  there  is  a  typographical 
error;  but  since  no  corrections  have  appeared  in 
subsequent  issues,  we  assume  that  the  formulae 
as  printed  are  as  Mr.  Mitchell  intended. 

Since  the  results  obtained  from  the  use  of 
these  formulae  actually  form  the  "meat"  of  the 
entire  article,  we  would  more  than  appreciate  for 
our  own  reference  further  clarification  by  Mr. 
Mitchell  in  a  future  issue  of  IP. 

A.  E.  Neumer,  Scientific  Bureau 
Bausch  &  Lomb  Optical  Company 


By  DR.  J.  L.  MAULBETSCH 
Kollmorgen  Optical  Corp. 

I  HAVE  looked  into  the  derivation  of 
the  formulas  given  by  Mr.  Mitchell* 
and  have  found  that,  except  for  a  misprint 
in  the  accompanying  line  drawing  (des- 
ignated Fig.  4  on  page  9  of  IP  for  March, 
1949;  reproduced  in  this  issue  as  Fig.  1) 
these  formulae  are  correctly  derived.  As 
a  matter  of  fact,  the  "simplified"  general 
formula  which  is  used  by  Mr.  Mitchell 
throughout  the  balance  of  his  article  can 
be  directly  derived  in  a  very  simple 
manner. 

The  errors  in  the  more  complete  for- 


*  "This  'Matching'  of  Projection  Optics,"  by 
Robert  A.   Mitchell;    IP   for  March  1949,  p.  7. 

t  "Optical  Factors  in  Arc  Lamp  Design,"  by 
J.  K.  Elderkin  and  Robert  A.  Mitchell;  IP  for 
May  1949,  p.  19. 

t  "Addenda:  'Matched*  Projection  Optics,"  by 
R.  H.  Cricks  and  Robert  A.  Mitchell;  IP  for 
June   1949,   p.    11. 


mula   given   in   the   aforementioned   line 
drawing   (Fig.  1)   are  as  follows: 

1.  The    plus    sign    in    the    numerator 
should  be  a  multiplication  sign,  so  that 

m 
the  numerator  should  read  /  X ; 


2.  In  the  denominator  the  term  multi- 
plying the  bracket  should  be  in  paren- 
theses; that  is,  the  bracket  is  to  be  multi- 


plied not  only  by  2 


but  also  by  the 


square  root.  The  denominator  should  be: 


V 


2  — 


3.  The  letter  b  was  not  referred  to  in 
the  caption  (Fig.  4  in  the  March  issue) 
and  should  have  been  given  as  the  "mir- 
ror diameter." 


4.  The    derivation    of    the    expression 
r 
2  —  is  somewhat  obscure,  and  since  the 

■R 

multiplying  factor  of  r  should  depend 
upon  the  ratio  of  aperture  height  h  to 
aperture  width  iv,  we  can  consider  the 

2 
factor  —  as  an  average  value,  which  is 


close  enough  in  most  cases. 

At  any  rate,  the  magnitude  of  the  term 
is  small  compared  with  the  term  given 
by  \/h2  +  iv-,  as  long  as  the  film  aper- 
ture is  not  rounded  off  at  the  corner  with 
too  large  a  radius. 

Single-Element  Lens  is  a  Simplification 

As  in  any  other  derivation  which  has 
to  be  technically  correct,  but  must  be 
presented  in  a  simple  form,  these  for- 
mulae can  be  subjected  to  various  criti- 


INTERNATIONAL  PROJECTIONIST 


October  1949 


cisms.  One  such  is  that  they  are  abso- 
lutely correct  only  for  a  schematic  pro- 
jection lens  consisting  of  a  single  ele- 
ment; while  all  projection  lenses  are 
compound  lenses. 

Mr.  Mitchell  shows  that  he  derives 
the  formulas  for  a  single  lens  as  shown 
in  his  drawings  (Figs.  1,  2  and  3  in  the 
March  issue  of  IP).  The  derivation  of 
equivalent  formulas  for  compound  lenses 
would  require  an  assumption  upon  the 
strength,  diameter  and  location  of  the 
rear  element  of  the  projection  lens,  and 
would  lead  into  complicated  derivations 
which  would  detract  the  attention  of  the 
reader  from  the  main  conclusions  of  the 
article. 

R.  H.  Cricks  (technical  editor  of  Ideal 
Kinema,  London)  attempts  to  present 
this  point  in  his  article,:}:  but  does  not 
do  so  correctly,  as  he  still  shows  in  his 
figures  a  projection  lens  consisting  of  a 
single  element. 

There  is  no  doubt  that  this  contro- 
versial discussion  could  go  on  almost 
interminably,  but  the  main  thing  to  re- 
member is  that  a  projection  lens  should 
make  full  use  of  the  light  which  is  avail- 
able; when  it  does  this  it  is  a  truly 
matched  lens. 

An  important  conclusion  is  that  the 
F-ratios  given  for  mirrors  and  projection 
lenses  are  not  consistent  with  each  other. 
As  Mr.  Mitchell  points  out,  this  would 
seem  to  be  a  subject  meriting  investiga- 
tion by  the  Society  of  Motion  Picture 
Engineers. 

Now,  finally,  the  author  of  the  article 
which  induced  the  foregoing  and  sundry 
other  comment,  has  his  say. 

By   ROBERT   A.   MITCHELL 

THE  mathematical  difficulties  men- 
tioned by  Mr.  Neumer,  of  Bausch  & 
Lomb,  are  probably  due  to  a  misprint  in 
the  general  formula  given  in  my  article* 
and  also  to  an  error  in  the  expression 
intended  to  give  the  length  of  the  diag- 
onal of  the  round-cornered  projector 
aperture.  This  error  was  pointed  out  by 
Dr.  Maulbetsch,  of  Kollmorgen. 

r 
In   place   of  the   erroneous  term   2  — 

IT 

a  new  expression  must  be  found  to  give 
the  length  of  the  diagonal  removed  by 
the  rounded  aperture  corners.  Examina- 

2 
tion  of  the  matter  reveals  that  —   (sug- 

7T 

gested  by  Dr.  Maulbetsch**  and  based, 
presumably,  on  my  own  erroneous  form) 
is  almost  as  unsatisfactory.  The  following 

**  Audit   this   point,   Dr.    Maulbetsch   observes: 
"This  was  not  suggested  by  me.    I  only  mention 
2 
—  as  the  factor  multiplying  r  and  state  that  it  is 

IT 

probably  used  as  an  average  value  by  Mr.  Mit- 
chell." 


line   of   reasoning,   however,   appears   to 
give  a  good  value. 

Let  a  square  inscribed  with  a  circle  be 
assumed.  Now  let  a  diagonal  be  drawn; 
and  this  diagonal  will,  of  course,  pass 
through  the  common  center  of  square 
and  circle. 

Designate  that  part  of  the  diagonal 
from  center  to  the  circumference  of  the 
circle  as  r,  and,  continuing  in  the  same 
direction,  that  part  from  circumference 
to  the  corner  of  the  square  as  x.  Let  us 
now  define  the  sum  of  r  and  x  as  d, 
which  will  be  considered  as  the  diagonal 
of  a   smaller  square. 

It  will  be  seen  that  the  length  of   a 
side  of  the  smaller  square  is  r.  The  prob- 
lem is  to  find  the  length  of  x. 
d  =   r\/2  _ 
x  +  r  —  r\/~2 
x  =  r  \/  2  — -  r 

But  the  length  and  diagonal  lost  from 
an  aperture  will  be  2x,  or  2r  \/2  —  2r. 
This,  then,  is  the  desired  quantity  to 
subtract  from  V  h2  +  w2  to  give  the 
length  of  the  diagonal  of  a  round-cor- 
nered aperture.  (As  Dr.  Maulbetsch  sug- 
gested, this  term  is  a  function  of  the 
ratio  df  aperture  height  to  aperture 
width  for  any  given  radius  of  corner 
curvature;  but  it  will  be  readily  appre- 
ciated that  large  variations  in  aperture 
ratio  produce  only  insignificant  depar- 
tures from  the  true  value  of  the  sub- 
tracted expression.) 

This,  however,  is  a  matter  of  minor 
importance  and  does  not  enter  into  the 
basic  structure  of  the  main  formula  for 
matched    projector    optics. 

The  "simplified"  equation  derived 
from  the  general  formula  was  set  up  in 
type  by  the  printers,  and  is  correct  as 
it  appeared  in  IP. 


The  general  formula  for  the  calcula- 
tion of  perfectly  matching  lens  speed 
(together  with  others  associated  with  the 
geometric  aspect  of  lens  matching)  is 
presented  herewith  in  a  form  more  ac- 
ceptable to  technicians  in  the  optical 
field.  An  algebraic  derivation  of  the  gen- 
eral formula  is  also  offered. 

The  General  Formula 

The  F-number  of  a  projection  lens  of 
given  E.F.  which  exactly  matches  any 
particular  lamp  optical  system  is  deter- 
mined by  the  following  formula  in  which 
a  is  the  diagonal  of  the  projector  aper- 
ture, b  is  the  diameter  of  the  lamphouse 
converging  element  (reflector  or  con- 
verger of  a  condensing-lens  assembly), 
/  is  the  equivalent  focal  length  of  the 
projection  lens,  and  m  is  the  "working 
distance"  (the  length  of  a  straight  line 
extended  from  the  edge  of  the  converger 
to  the  plane  of  the  projector  aperture, 
and  intercepting  that  plane  perpendicu- 
larly). All  dimensions  substituted  for  the 
letters  of  the  formula  should  be  in  like 
units  of  linear  measure. 


Fo 


fm 


bf  +  a(f+  m) 
The  foregoing  equation,  determinate  for 
all  values  of  a,  is  the  same  formula  which 
appeared   in   an    indeterminate   form   in 
the  March  1949  issue  of  IP. 

The  value  of  a,  the  length  of  the  diag- 
onal of  the  aperture,  is  given  by: 


a  =  V  h2  +  w2  —  (2r  V  2  —  2r) 
in  which  h  is  the  height  and  w  the  width 
of  the  picture  aperture,  and  r  the  radius 
of  the  rounded  aperture  corners.  When 
the  aperture  has  square  corners,  r  =  0, 
hence  the  expression  2r  y/  2  —  2r 
reduces  to  0. 

In   the    case    of   the    standard    35-mm 


FIG.  1.    Here  is  reproduced  the  drawing  from  the  March  1949  issue  of  IP  (Fig.  4  on  p.  9),  beneath 
which  appears  the  original  caption.    This  drawing  and  caption  figure  prominently  in  the  accom- 
panying discussion. 


This  formula  is  the  basis  for  the  optical  matching  principles  discussed  in  the  accompanying  article. 
The  simplified  35-mm  matched  optics  formula  was  derived  from  this  general  formula,  in  which  f  is 
the  E.  F.  of  the  projection  lens,  m  is  the  working  distance  of  the  condenser  element,  h  is  aperture 
height,  w  is  aperture  width,  and  r  is  the  radius  of  the  aperture  corners  if  they  be  rounded.    All 

dimensions  are  in  inches. 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


He  gives  the  scene  its  heartbeat... 


THIS  meeting  of  mother  and  child  is  no 
make-believe — not  to  the  movie-goers! 

To  them,  it  is  as  real  as  life  itself, 
thanks  to  the  director  of  the  picture. 
Through  his  perceptive  handling  of  ac- 
tion, dialogue,  and  camera,  he  has  given 
the  scene  its  human  touch,  its  heartbeat 
.  .  .  made  the  audience  feel  its  warmth,  its 
mood — and  live  the  moment,  one  with 
the  personalities  on  the  screen. 


And  this  achievement  is  the  mark  of 
his  mastery  of  the  dramatic;  the  gauge  of 
his  creative  contribution  to  the  motion 
picture  art. 

But  if  such  artistry  is  to  have  full  ex- 
pression, the  director  must  have  the  as- 
sistance of  film  that  gives  him  ample 
freedom  to  achieve  the  effects  he  desires. 
This  freedom  he  finds  in  the  family  of 
Eastman  motion  picture  films. 


EASTMAN    KODAK    COMPANY 


ROCHESTER    4,    N.    Y. 


J.   E.    BRULATOUR,    INC.,    DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •     HOLLYWOOD 


sound  film  aperture  of  dimensions  0.600 
X  0.825  inch,  a  —  1.041  inch  if  the  coi> 
ners  are  square,  and  1.002  if  the  corners 
are  curves  of  0.047-inch  radius. 

Computations  are  greatly  shortened  by 
employing  1  inch  as  the  length  of  the 
aperture  diagonal  of  the  35-mm  projec- 
tion machine,  an  approximation  which 
does  not  affect  the  results  materially.  It 
is  necessary,  when  making  use  of  this 
simplification,  to  express  all  quantities 
in  the  general  formula  in  inches.  The 
"simplified"  formula  given  in  IP*  was 
obtained  by  letting  a  in  the  general 
formula  equal  1.  There  is  no  need  to 
repeat  the  simplified  formula  here  as 
the  new  determinate  form  supplants  it. 

The  Efficiency  Ratio 

The  geometric  efficiency  of  a  projec- 
tion lens  is  the  ratio  of  the  speed  of  a 
given  lens  to  the  speed  of  a  perfectly 
"matched"  lens  of  the  same  focus.  Each 
projection  setup  must  be  treated  indi- 
vidually, for  a  lens  which  matches  one 
lamp  does  not  necessarily  match  another. 

Following  are  three  formulas  for  the 
calculation  of  the  efficiency-ratio  of  any 
projection  lens.  Symbols  are  the  same 
as  those  used  in  the  general  formula.  All 
quantities  having  an  inferior  0  appended 
refer  to  the  perfectly  matched  lens. 

F0 
E  =  (A) 


E  = 


E  = 


fm 


(B) 


(C) 


F  [bf  +  a{f  +  m)-\ 
The  value  of  E  may  be  multiplied  by  100 
to  express  the  efficiency-ratio  as  a  per- 
centage. 

The  diameter  of  any  lens   (considered 
as  a  single  element)   is  given  by: 

/ 

d  =  

F 

and  the  diameter  of  a  perfectly  matched 
lens  is  given  by: 


bf  +  a(f  +  m) 


d0  = 


Derivation  of  the  Formula 

The  base  of  operations  in  developing 
the  general  optical  matching  formula  is 
the  simple  ratio  which  defines  the  speed 
rating  of  a  lens  (F-number)  : 


F  = 


f 


d 


(1) 


The  first  member  of  (1)  is  regarded 
as  the  unknown  quantity,  the  value  of 
which  requires  transformation  of  the 
second   member  into   an  expression   for 


the  "matched-lens"  value  of  F,  (herein- 
after represented  by  F0)  for  any  given 
values  of  converger  diameter,  working 
distance,  lens  E.F.,  and  aperture  dimen- 
sions. 

Throughout  this  discussion  the  lens  is 
considered  as  a  single-glass  element 
placed  at  a  distance  from  the  aperture 
equal  to  its  focal  length — "infinity  focus 
position."  These  assumptions  are  judged 
entirely  in  keeping  with  the  requirements 
of  the  problem. 

The  dimensional  characteristics  of  the 
diverging  beam  of  light  which  pours 
lensward  from  the  aperture  are  of  the 
utmost  importance.  Viewing  the  condi- 
tions in  two-dimensional  cross-section, 
we  may  say  that  the  outermost  sides  of 
the  beam  emerging  from  the  aperture 
produce  an  angle  whose  vertex  is  located 
at  some  point  between  the  aperture  and 
the  converger. 

The  degree  of  divergence  of  the  outer- 
most sides  of  the  emergent  beam  is  a 
resultant  of  two  functions:  first,  the  dis- 
tance separating  converger  and  aperture; 
second,  the  ratio  of  converger  diameter 
to  aperture  diagonal.  This,  of  course, 
suggests  the  use  of  the  calculus,  but  the 
problem  also  lends  itself  to  algebraic 
solution. 

In  the  imaginary  case  of  a  projector 
aperture  no  larger  than  a  mathematical 
point,  the  lens  F0  value  will  be  the  same 
as  the  "spurious"  F  value  which  is  com- 
monly (and  unwisely)  used  to  rate  the 
speed  of  the  lamp.  The  situation  is  com- 
plicated by  the  fact  that  a  real  aperture 
is  an  area  of  quite  appreciable  mag- 
nitude. 

The  terms  "top"  and  "bottom"  of  the 
aperture  used  in  the  following  paragraph 
are  understood  to  refer  to  the  extremities 
of  the  aperture  diagonal. 

If  a  line  be  drawn  from  the  top  of  the 
converging  element  to  the  bottom  of  the 
aperture  and  extended,  and  another  be 
drawn  from  the  bottom  of  the  converger 
to  the  top  of  the  aperture  and  extended, 
the  extended  lines  will  form  the  outer- 
most   sides    of    the    diverging    emergent 


beam.  Outside  the  limits  of  the  emergent 
beam  so  defined  no  direct  rays  of  light 
from  the  converger  will  in  any  case  be 
found. 

The  two  lines  produced  in  the  afore- 
mentioned procedure  will  be  seen  to 
cross  at  some  point  on  that  section  of  the 
optical  axis  which  extends  from  the  cen- 
ter of  the  converger  to  the  center  of  the 
aperture.  This  point,  labelled  P  in  Fig.  2, 
is  the  vertex  of  the  angle  formed  by  the 
sides  of  the  emergent  beam. 

The  distance  between  P  and  the  cen- 
ter of  the  aperture  may  now  be  ascer- 
tained. Point  P  divides  the  section  of 
optical  axis  from  aperture  to  converger 
(working  distance,  designated  by  m) 
into  two  parts,  y  and  z.  Part  y  is  that 
part  which  extends  from  P  to  the  aper- 
ture. Because:  j,i 

m   =  y   +   z  (2) 

the  value  of  m  in  terms  of  y  is: 

m  —  y  +  ry  (3) 

in  which  r  is  the  ratio  of  z  to  y.  Solving 
for  y  we  obtain: 

m 

y    =    (4) 

!+' 
But  the  lines  drawn  to  define  the  emerg- 
ent  beam   will   be   seen   to   form    (with 
converger    and    aperture    "planes")    two 
similar  triangles,  hence: 

z  b 

r   =   -    =   -  (5) 

y  a 

in  which  6  is  the  diameter  of  the  con- 
verger and  a  is  the  diagonal  of  the  aper- 
ture.  Therefore : 

m 
y  =  (6) 


nt 


1  +  — 
a 
The  next  step  involves  determining  the 
value  of  the  diameter  (or  diagonal)  d  of 
the  emergent  beam  at  a  distance  /  from 
the  aperture  equal  to  the  focal  length  of 
the  projection  lens.    The  following  self- 


t > 


FIG.  2.  Graphical  exposition  of  derivation  of  general  formula  for  computing  lens  matching  speeds. 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


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TRADE   MARK    REG 


NEW     MAGNETIC    STABILIZER 

This  modern  lamp  produces  all  the  light  there  is. 
...  It  is  the  standard  equipment  of  the  nation's  largest 
and  finest  theatres.  .  .  .  Used  by  90%  of  the  largest 
Drive-In  Theatres. 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  white  light  volume 
when  used  with  projectors  that  have  efficient  DISC 
type  revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions.  .  .  .  They  are  Und.  Lab.,  Inc. 
listed  and,  therefore,  not  insurance  hazards. 


I  1 


WHY    EXPERIMENT? 


J.E.McAULEY  MFG. CD. 

552-554    WEST   ADAMS    STREET 
CHICAGO   6.  ILLINOIS 


/  I 


INTERNATIONAL  PROJECTIONIST 


October  1949 


evident 
to  give 

proportion  may  be  solved  for  d 
(9). 

y        S  +  y 

—                          \  1 ; 
a              d 

or: 

dy  =  a(f  +  y)                 (8) 

hence: 

An  Improved  Concentrated-Arc  Light 


By  using  (9)  a!  is  eliminated  from  (1). 

fy 

(10) 


^0       = 


a(f  +  y) 

and  by  using  (6),  y  is  thrown  from  (10). 
fm 


1   + 


F„    = 


\ 


(11) 


/    + 


b 
1  +  — 
V  a  J 

Reduction  of  (11),  which  is  indetermi- 
nate when  a  equals  0,  may  be  accom- 
plished very  simply  to  give  the  following 
convenient  and  perfectly  determinate 
form  of  the  general  formula  for  matched 
projector  optics. 

fm 

F0  =  ■ (12) 

bf  +  a(f  +  m) 

The  geometric  efficiency-ratio  formula 
(C)  is  derived  from  (12)  by  obvious 
processes. 

The  writer  invites  further  criticism  and 
comment  from  the  technical  field  in  re- 
gard to  the  concept  of  matched  projector 
optics  proposed  by  him. 

'Ethyloid'  a  New  Film  Cement 

"Ethyloid"  is  a  new  all-purpose  film 
cement  made  and  distributed  by  Fisher 
Mfg.  Co.,  529  Merchants  Road,  Roches- 
ter, 9,  N.  Y.  It  is  asserted  that  Ethyloid 
cement  will  stand  exposed  to  the  air  for 
24  hours  without  congealing,  that  it  does 
not  build  up  on  the  splice  and  that  it 
works  fast. 

A  sample  bottle  of  this  cement  will  be 
sent  to   any  projectionist  upon  request. 


Weinke,  Motiograph  Designer,  Dies 

Emil  J.  Weinke,  68,  chief  projector 
design  engineer  for  Motiograph,  Inc., 
died  recently  in  Chicago  after  a  long  ill- 
ness. Weinke  was  an  industry  pioneer, 
having  been  associated  with  Motiograph 
since  the  company  was  founded. 

The  originator  of  many  advances  in 
projector  design  and  technique,  Weinke 
was  granted  numerous  patents  during  his 
long  engineering  career. 


IP  READERS  will  be  reminded  of  the 
several  articles  which  appeared  in 
these  pages  anent  concentrated-arc  light 
sources1'2'3  by  the  presentation  before 
the  recent  SMPE  convention  in  Holly- 
wood of  a  description  of  a  new  high- 
power,  high-intensity  electric  light  de- 
veloped by  Western  Union  Telegraph 
Co.  Obviously,  W.  U.  has  pursued  as- 
siduously the  development  of  the  zircon- 
ium concentrated-arc  light. 

The  data  presented  herein  is  a  resume 
of  the  information  supplied  to  the  SMPE 
meeting  by  W.  D.  Buckingham,  engineer 
for  W.  U. 

The  luminescent  source  of  the  new 
arc  light  is  two-tenths  of  an  inch  in  diam- 
eter and  one-eighth  as  bright  as  the  sun. 
The  light  source,  which  operates  in  the 
open  air  and  not  in  a  glass  bulb,  is  a 
pool  of  molten  zirconium  metal  main- 
tained at  a  temperature  near  6500°F. 

Stability,  High  Luminescence  Cited 

The  new  light  source  is  extremely 
stable  in  operation,  producing  a  uni- 
formly bright,  sharply  defined  circular 
spot  of  white  light  of  dazzling  brightness. 
In  a  1000-watt  lamp,  operating  at  55 
volts  and  18  amperes  a-c,  the  source 
spot  is  two-tenths  of  an  inch  in  diameter 
and  has  a  maximum  brightness  of  130,- 
000  candles  per  square  inch,  and  20 
times  the  brightness  of  the  ordinary 
tungsten  filament  lamp.  The  total  light 
from  the  new  lamp  is  20,00  lumens. 

The  new  lamp,  named  Telcoarc,  is  al- 
ready being  tried  in  a  few  of  the  many 
fields  in  which  they  are  expected  to  be 
used.  A  16-mm  motion  picture  projector 
designed  to  use  a  1000-watt  lamp  of  the 
new  type  produces  three  times  as  much 
light  on  the  screen  as  the  currently  avail- 
able projectors  using  a  1000-watt  tung- 
sten filament  lamp.  The  new  light,  being 
a  much  smaller  source,  will  also  produce 
sharper,  clearer  pictures  on  the  screen. 

Operation  of  the  new  lamp  in  the  open 
air  without  an  enclosing  glass  bulb  per- 
mits a  high  output  of  radiations  in  the 
infra-red  and  the  ultra-violet  regions  of 
the  spectrum,  which  are  cut  off  by  the 
glass  bulb  of  most  light  sources. 

In  one  case,  the  new  light  was  tried 
in  an  ultra-violet  microscope  working  at 
2600  Angstroms  and  gave  20  times  as 
much  ultra-violet  energy  as  a  quartz 
mercury-vapor  lamp.  In  a  searchlight 
application,  it  was  reported,  the  new 
lamp  produced  over  7  million  beam 
candlepower.  A  tungsten  filament  lamp 
of  the  same  wattage  in  the  same  equip- 
ment produced  less  than  500,000  beam 
candlepower. 

1  "The   W.    U.    Concentrated    Arc    Lamp";    IP 
for  April  1946,  p.  16. 

2  "A    Crystal-Gazer    at    Work" ;    IP    for    June 
1946,  p.  12. 

3  "Concentrated-Arc     Light     Sources";     IP     for 
April  1947,  p.  14. 


In  addition  to  furnishing  a  small,  high- 
intensity  source  with  high  lumen  and 
actinic  efficiency,  the  new  lamp  is  said 
to  have  a  continuous  spectral  energy  dis- 
tribution and  a  color  temperature  which 
holds  constant  at  3600°  K.  These  last 
two  characteristics  are  of  particular  im- 
portance in  color  photography. 

In  spite  of  operating  in  the  open  air 
at  this  extremely  high  temperature,  the 
new  lamp  can  be  made  to  have  a  life  of 
several  hundred  hours.  This  is  due,  it 
was  explained,  to  a  unique  operating 
principle  whereby  the  zirconium  metal 
is  constantly  renewed  and  reproduced 
from  its  own  products  of  combustion. 
The  electrodes  are  small.  When  they  be- 
come exhausted  from  long  use,  new  ones 
may  be  inserted  quickly  and  easily.  The 
new  lamps  can  be  made  in  sizes  up  to 
several  thousand  watts,  and  to  operate 
from  either  a-c  or  d-c. 

Operating  Advantages  Cited 

With  its  advantage  of  intense,  steady 
light  from  a  small  source,  ease  of  opera- 
tion long  life,  the  absence  of  toxic  fumes 
or  any  fire  hazard,  and  operation  from 
a-c,  the  new  lamp  is  expected  to  be  used 
in  many  places  heretofore  preempted 
by  other  light  sources. 

A  previous  Western  Union  invention 
based  on  the  same  principles  was  the 
concentrated-arc  lamp,  a  pin-point 
source  of  intensely  bright  light,  which 
was  released  from  wartime  security  re- 
strictions three  years  ago.  However, 
W.  U.  engineers  continued  their  search 
for  an  even  higher  powered  and  more 
intense  light  to  meet  many  other  needs, 
and  the  new  lamp  resulted. 


The  W.U.  concentrated-arc :.l.  Zirconium  metal 
surface  (active  luminous  area);  2,  Specially 
prepared  electrodes;  3,  Differentially  coiled 
electro  magnet  with  wide  pole  pieces  for  ver- 
tical arc  stream  control;  4,  Permanent  magnet 
for  lateral  arc  stream  control;  5,  Micrometer 
screw    control    for    adjustment    of    electrodes. 


10 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


The  term  "National"  is  a  registered  trade-  mart  of 

NATIONAL  CARBON  COMPANY,  INC. 

Unit  of  Union  Carbide  I'm  and  Carbon  Corporation 
30  East  42nd  Street,  New  York  17.  N.  Y. 

Division  Sales  Offices:  Atlanta,  Chicago,  Dallas, 
Kansas  City,  New  York,  Pittsburgh,  San  Francisco 


with  "NATIONAL"  HIGH  INTENSITY 
PROJECTOR  CARBONS 
and  make  box  office 

BOOM! 


-££ 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


11 


Fire  Extinguishers  in  Projection  Rooms 


By  GEORGE  R.  STEWART 
I A   Local   150,   Los  Angeles 

LAST  year  sometime  IP  published  data 
bearing  on  the  danger  inherent  in  the 
use  of  carbon-tetrachloride  fire  extin- 
guishers in  projection  rooms.*  Whether 
this  warning  was  heeded  by  projection- 
ists generally  I  don't  know;  but  if  it 
wasn't,  then  the  projectionist  craft  is 
strangely  indifferent  to  one  of  the  most 
serious  threats  to  their  physical  welfare 
— and  how! 

It  seems  that  we  are  now  faced  with 
a  new  danger  which  parallels  the  carbon- 
tet  menace.  Many  projection  rooms  in 
the  Los  Angeles  area  (and  plenty  of 
others,  for  all  I  know)  are  now  equipped 
with  15-pound  C02  (carbon  dioxide) 
bottles  which  were  purchased  from  U.S. 
Navy  surplus  supply. 

On  the  outside  of  these  bottles  appears 
the  manufacturer's  statement:  "Non- 
poisonous,  but  will  not  support  life" — 
which  we  understand  to  mean  that  when 
the  gas  is  used  there  must  be  available 
a  goodly  amount  of  fresh  air  so  as  to 
prevent  the  user  being  overcome,  possibly 
lapsing  into  unconsciousness. 

CAB  Plane  Crash  Report  on  C00 

Our  suspicions  as  to  the  undesirability 
of  using  these  C02  fire  extinguishers  in 
a  confined  space  like  a  projection  room 
were  confirmed  recently  when  we  re- 
ceived a  copy  of  the  report  rendered  by 
the  Civil  Aeronautics  Board  on  the  air- 
plane crash  which  claimed  the  lives  of 
all  43  persons  aboard  just  outside  Mt. 
Carmel,  Pa.,  on  June  17,  1948  (Sa-172; 
File  No.  1-0075-48).  The  facts  given  in 
the  following  paragraphs  were  culled 
from  this  report. 

A  United  Air  Lines  DC-6  plane  en 
route  from  Los  Angeles  to  New  York 
stopped  at  Chicago  where  it  was  given 
a  routine  station  inspection,  serviced  and 
loaded,  taking  off  at  10:44  a.  m.  At  11 :55 
the  plane  captain  reported  to  United  at 
New  York  that  the  plane  was  mechani- 
cally okay  for  a  return  trip.  At  12:27 
p.  m.  the  crew  acknowledged  clearance 
to  descend  to  an  altitude  of  11,000  feet. 

At  12:31  p.  m.  the  plane  notified  New 
York  that,  following  a  warning  signal  by 
the  smoke  indicator,  C02  bottle  fire  ex- 
tinguishers had  been  released  in  the  for- 
ward baggage  compartment  (under  the 
cockpit)  and  that  an  emergency  descent 
was  being  made.  The  crash  occurred  at 
12:41  p.  m. 

*  "The  Anatomy  of  Nitrocellulose  Film:  Its  Import 
to  the  Projectionist,"  by  Robert  A.  Mitchell;  IP  for 
February  1948,  p.  5. 


Sections  11  and  12  of  the  CAB  report 

are  particularly  interesting: 

''Section  11.  After  the  release  of  CO., 
gas  hazardous  concentrations  of  the  gas 
entered  into  the  cockpit. 

'Physically,  Mentally  Incapable' 

''Section  12.  Due  to  the  physiological 
and  toxic  effects  of  high  concentrations 
of  C02  gas  in  the  cockpit,  which  would 
probably  not  have  occurred  had  the  cabin 
pressure  relief  valves  been  open,  the 
members  of  the  flight  crew  .  .  .  were  ren- 
dered physically  and  mentally  incapable 
of  performing  their  duties." 

Now,  a  projection  room  is  not  nearly 
as  confining  as  an  airplane  cockpit,  but 
the  fact  remains  that  CO,  is  very  nasty 
stuff  and  that  nobody  can  foretell  the 
circumstances  under  which  it  might  be 
used  in  an  emergency.  There  are  other 
and  more  efficient  fire  extinguishers  than 
the  C02  type  available,  and  projection- 
ists everywhere  should  take  immediate 
action  looking  toward  the  removal  of 
these  units.  It's  a  damn  sure  bet  that 
dilatory  inspectors  and  exhibitors  won't 
move  in  this  matter  unless  they  are 
prodded — or   pushed.    Push   'em. 

Commenting  on  the  foregoing  in  par- 
ticular    and     fire     extinguishers     in 
general  is  this  very  interesting  com- 
munication 

By    ROBERT  A.   MITCHELL 

!T  is  indeed  a  pleasure  to  read  a  con- 
tribution from  a  projectionist  who  is 
obviously  alert  and  extremely  interested 
in  his  work;  but  I  cannot  subscribe  to 
the  conclusions  of  the  article.  It  is  always 
unwise  to  deduce  generalizations  from 
one  special  case,  and  that  is  exactly  what 
Mr.  Stewart  seems  to  have  done.  Further- 
more, the  possibility  that  the  data  given 
by  Sections  11  and  12  of  the  CAB  report 
are  incorrect  is  very  strong,  for  the  fol- 
lowing reasons: 

1.  All  43  occupants  of  the  plane  were 
killed  in  the  crash,  hence  depriving 
the  report  of  facts  derived  from  the 
testimony  of  first-hand  witnesses.  This 
materially  weakens  the  credibility  of 
the  data. 

2.  The  fact  of  the  existence  of  smoke 
indicates  trouble  of  a  more  serious 
nature  than  any  probable  concentra- 
tion in  the  air  of  the  cockpit  of  CO, 
released  from  the  extinguishers. 

Carbon  Monoxide  Suggested 

3.  The  manner  of  incapacitation  of  the 
flight  crew  as  given  in  Sec.  12  does 
not  suggest  the  effects  of  C02  at  all, 
but  seems  rather  more  like  poisoning 


by  a  toxic  gas  such  as  carbon  mon- 
oxide. 

4.    The  time  between  the  release  of  C02 
from   the    extinguishers   in    the   bag- 
gage compartment  under  the  cockpit 
(12:31  p.m.)   and  the  crackup  of  the 
airplane     (12:41    p.m.) — a    mere    10 
minutes — does  not  seem  sufficient  for 
the    production    of    an    asphyxiating 
concentration  of  CO,  and  subsequent 
incapacitation    of   the    crew.    Carbon 
dioxide,    we    know,    is    a    heavy    gas 
(approx.   IV2  heavier  than  air)    and 
does  not  diffuse  upwards  readily. 
The  foregoing  four  points  are  offered 
not  to  strengthen  my  own  case  in  favor 
of   carbon-dioxide   extinguishers,    but   to 
show  the  imprudence  of  placing  complete 
reliance  on  data  not  wholly  authenticated 
or  in  only  one  set  of  data.  The  CAB  re- 
port furnishes  a  "lead"  for  further  inves- 
tigation,  but  as  the  sole  basis  for  con- 
demning the  use  of  carbon-dioxide  extin- 
guishers in  projecting  rooms  jt  is  value- 
less. 

Character  of  Both  Gases 

IP  readers  should  guard  against  con- 
fusing carbon  dioxide  and  carbon  monox- 
ide. The  two  are  entirely  different.  The 

(Continued    on    page    30) 


Carbon -let   Extinguishers 

Here  is  an  excerpt  from  the  article 
referred  to  by  Mr.  Stewart.* 

Film  fires  may  be  put  out  by  cooling 
the  film  below  its  ignition  temperature. 
Ordinary  fires  may  be  extinguished  by 
blanketing  the  blaze  with  an  oxygen- 
excluding  gas  such  as  carbon-tetrachlor- 
ide vapor,  but  this  is  not  true  of  burning 
film.  Film  contains  its  own  oxygen. 

Efficiency  Seriously  Doubted 

A  carbon-tet  extinguisher  may  or  may 
not  put  out  a  film  fire,  depending  upon 
the  intensity  of  the  blaze.  A  hot  fire  will 
immediately  convert  the  carbon-tet  to 
gas,  thus  robbing  it  of  any  cooling  effect 
it  might  have. 

In  addition  to  its  inefficacy,  the  nature 
of  vaporized  carbon-tet  renders  this  type 
of  extinguisher  extremely  hazardous  to 
the  projectionist.  The  fumes  of  carbon- 
tet  are  injurious  when  inhaled  (more 
poisonous  than  chloroform)  and,  what  is 
worse,  they  react  with  the  inevitably- 
present  water  vapor  of  the  air  in  contact 
with  hot  iron  or  iron  oxides  to  form 
lethal  phosgene.  (Phosgene,  the  chemi- 
cal name  for  which  is  carbonyl  chloride, 
is  a  poison  gas  of  warfare.) 


12 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


13 


DeVry's    Koolite'  Unit  for  H-l  Arcs 

By  E.  W.  D'ARCY 

Chief  Engineer,  DeVry  Corporation 

The  appended  contribution  was  received  too  late  to  be  included  in  the 

symposium   anent  cooling   methods   for  high-intensity  projection   which 

appeared  in  these  columns  last  month. 


THE  adverse  effects  of  excess  heat 
upon  the  film  are  so  well  understood 
throughout  the  projection  field  as  to  re- 
quire no  extensive  recounting  here.  Suf- 
fice it  to  say  that  not  only  is  the  film 
damaged  in  the  first  instance  of  light- 
heat  contact  to  an  extent  which  prevents 
a  good  screen  image,  but  that  particular 
print  will  render  impossible  good  projec- 
tion in  subsequent-run  theatres.  This  is 
quite  apart  from  the  damage  wrought 
upon  projector  parts  and  the  ever-pres- 
ent possibility  of  physical  harm  to  the 
projectionist. 

With  a  high-intensity  carbon  arc  oper- 
ating at  75  amperes  the  temperature  at 
the  center  of  the  aperture  is  approxi- 
mately 1350°  F.  The  absorption  of  heat 
by  the  film  is  proportionate  to  the  dens- 
ity of  the  silver  deposit  on  the  latter,  thus 
a  dark  scene  absorbs  sufficient  heat  to 
severely  emboss  the  film  and  result  in 
alternate  high  and  low  spots  thereon. 

Dual  Function  Required 

We  feel  that  the  cooling  method  em- 
ployed to  overcome  this  difficulty  must 
serve  a  dual  purpose:  it  must  cool  both 
the  film  and  the  adjacent  projector  parts. 
Two  basic  methods  for  accomplishing 
this  purpose  suggest  themselves  imme- 
diately: liquid  cooling  through  channels 
installed  in  the  aperture  bracket,  and 
forced  cooling  by  means  of  directing  an 
air  blast  against  both  the  film  and  pro- 
jector parts. 

Based  on  extensive  tests,  DeVry  has 
developed  the  "Koolite"  system  of  air- 
blast    cooling    for    the    projector    head. 


Fig.  1  shows  the  mounting  of  this  unit 
and  the  means  for  ingress  and  exit  of 
the  air. 

Indicative  of  the  effectiveness  of  this 
system  are  the  two  curves  shown  in 
Fig.  2.  These  curves  reflect  data  compiled 
without  film  in  the  projector,  a  condition 
not  of  normal  operation  but  still  one 
frequently  employed  when  checking  uni- 
formity of  illumination,  arc  lamp  align- 
ment and  mirror  adjustment.  Fig.  3  tells 
the  story  of  what  happens  with  and  with- 


300*1: 


in  Fig.  2.  It  can  be  seen  that  after  60 
minutes'  operation  the  top  temperature 
rise  is  85°;  with  air-blast  cooling,  how- 
ever, this  rise  is  held  to  35° — a  clear-cut 
gain  of  50°.  The  Koolite  unit  consists  of 
a  blower  which  directs  an  air  blast  over 
the  entire  aperture  area  past  the  face 
of  the  film  and  an  exhaust  section  which 
removes  the  heated  air  from  the  projec- 
tor head. 

A  good  indication  of  the  degree  of 
cooling  possible  by  an  air-wipe  directed 
at  the  aperture  is  given  by  measurements 
obtained  using  a  thermocouple  installed 
in  an  asbestos  plate  and  then  clamped 
into  position  in  the  exact  center  of  the 
aperture.   The   results   were   as   follows: 

Light  Source:    70-Amp.  Suprex  Carbons 

No  Air  Blast:  1350°  F. 

With  Air  Blast:    450°  F. 

During   these   air-blast   tests  we   have 

repeatedly  run  test  loops  of  film  through 


ZOO 


0 
MINUTE5 

FIGURE  2 

out  the  blower  in  operation:  the  blower 
reduces  the  temperature  200°  in  the 
immediate  area  of  the  aperture,  and  it 
undoubtedly  exerts  a  marked  beneficial 
effect  upon  those  other  parts  exposed  to 
arclight  cone   spillover. 

Figure  3  corroborates   the   data   given 


ioo°r 


0 


WITH  FILM 


BLOWERS 
I 
BLOWERS  ON 


OFFv 


10 

MINUTE5 
FIGURE  3 


a  projector  in  excess  of  3,000  times  with- 
out any  sign  of  film  damage.  Contrari- 
wise, however,  similar  runs  of  film  have 
resulted  in  severe  embossing  and  extreme 
brittleness.  It  is  understood,  of  course, 
that  this  air  blast  is  directed  across  not 
at  the  face  of  the  film. 


The  Starke  Cycloramic  Projection  Screen 


FIG.  1.     'Koolite'  mounted  on  DeVry  projector. 


By  HERBERT  A.  STARKE 
I A   Local   150,   Los  Angeles 

SINCE  the  advent  of  sound  pictures 
the  need  for  a  motion  picture  screen 
which  would  reflect  a  suitable  amount 
of  light  without  harmful  glare  has  been 
recognized  within  the  industry.  When 
viewing  the  auditorium  it  has  been  noted 
that  the  front  and  side  seats  are  the  last 
to  be  occupied.  The  audience  has  been 
keenly  aware  of  the  fact  that  the  picture 
image  did  not  appear  pleasing  from  this 
area. 

The  Cycloramic  screen  has  been  de- 
signed to  overcome  this  fault.  Tests  by 
Photo  Research  Corp.  show  that  there  is 
no  fall-off  of  screen  light  up  to  and  in- 
cluding 60  degrees  off  center.  To  at- 
tain these  results  a  top  grade  of  combed 
cotton  was   selected.     The   screen    body 


consists  of  three  layers  of  this  material. 
The  threads  of  each  layer  are  impreg- 
nated with  opposing  chemicals,  the  na- 
ture of  which  we  do  not  wish  to  divulge 
at  this  time. 

New  Optical  Principle  Cited 

We  believe  that  we  are  introducing 
an  entirely  new  physical  (optical)  prin- 
ciple in  the  production  of  this  screen. 
Heretofore  the  natural  yellowing  of 
screen  fabrics  had  been  temporarily 
counteracted  by  the  addition  of  a  blue 
tint  which  was  added  to  the  plasticizer. 
This  was  applied  to  the  fabric,  and  when 
combined  with  the  yellow  to  obtain  the 
illusion  of  white,  the  yellow  ground  was 
plus-blue,  creating  objectionable  grayish 
tones  which,  in  turn,  absorbed  a  severe 
amount  of  light. 

The   Cycloramic   process   produces   an 


14 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


indiscernible  fluorescence  which  is  acti- 
vated by  the  ultra-violet  rays  emanating 
from  the  arc  source.  This  creates  in- 
tensive light  reflection. 

It  is  emphasized  that  the  Cycloramic 
screen  contains  no  plasticizers  or  pig- 
ments whatsoever.  Whether  they  be 
flaked  aluminum  or  white  pigments  com- 
bined with  ethyl  cellulose,  all  known 
plasticizers  have  been  found  to  discolor 
rapidly.  A  reliable  investigating  body 
has  certified  that  screen  surfaces  so 
treated  will  deteriorate  approximately 
4%  per  month  under  ideal  conditions, 
discoloration  beginning  immediately. 

Numerous  Advantages  Seen 

The  Cycloramic  screen,  however,  will 
not  discolor  from  natural  causes.  The 
surface  is  practically  indestructible  and 
is  not  subject  to  abrasion.  It  is  thor- 
oughly fireproof  as  well  as  being  immune 
to  fungus  or  mildew.  By  the  use  of 
specially  designed  machines,  a  seam  has 
been  created  which  is  practically  in- 
visible. 

This  screen  may  be  successfully 
packed  in  small  containers:  for  example, 
a  screen  18x24  ft.  is  shipped  in  containers 
having    an    inside    measurement    of    2.7 


cubic  feet  and  weighing  only  19  pounds, 
thereby  effecting  a  considerable  saving 
to  the  purchaser. 

During  the  long  series  of  tests  con- 
ducted principally  at  the  RKO  Studios, 
Hollywood,  it  was  established  that  by 
the  use  of  this  specially  woven  material, 
eliminating  the  need  for  perforations, 
perfect  sound  transmission  was  attained. 
The  increased  number  of  very  small  hole> 
(pores)  much  more  closely  spaced  than 
the  conventional  perforated  surfaces,  im- 
proved the  characteristics  at  the  higher 
frequencies  by  completely  reducing  back- 
stage reverberations  as  well  as  producing 
a  better  high-frequency  distribution  with- 
in the  audience  area. 

Individual  Theatre  Requisites 

The  B.  F.  Shearer  Company  has  estab- 
lished a  factory  at  Seattle,  Washington, 
for  the  production  of  the  Cycloramic 
screen.  It  is  their  policy  to  manufacture 
the  screens  to  exact  individual  theatre 
specifications  in  order  to  render  saleable 
front  and  side  seats,  enhance  color 
photography  as  well  as  reproduce  black- 
and-white  film  as  it  was  photographed, 
and  be  economical  due  to  such  features 
as  low  shipping  cost,  ease  of  installation 
and  cleaning,  as  well  as  durability. 


Strong's  New   Mighty  90'  75-125  Amp 
Reflector-Type  Projection  Arc 


DESIGNED  especially  for  those  appli- 
cations where  the  light  requirements 
far  exceed  the  capacities  of  lamps  here- 
tofore available,  the  Strong  Mighty  "90" 
75  to  125  ampere  high-intensity  projec- 
tion arc  lamp  was  unveiled  at  the  recent 
TESMA  theatre  equipment  exhibit  at 
Chicago.  This  new  lamp,  a  product  of 
The  Strong  Electric  Corp.,  Toledo,  is 
said  to  project  a  volume  of  light  even 
far  beyond  that  necessary  to  illuminate 
the  tremendous  screens  used  in  the  larg- 
est drive-ins. 


The  Mighty  "90",  which  burns  a  9-mm 
x  20"  plain  high-intensity  positive  with  a 
5/16"  x  9"  copper-coated  negative  at  90 
amperes,  delivers  21,000  lumens.  The  gen- 
erous sized  lamphouse  and  rugged  burner 
mechanism  have  been  designed  to  burn 
the  larger  carbons  at  up  to  130  amperes, 
at  which  current  26,000  lumens  are  avail- 
able. This  compares  with  the  17,000 
lumens  projected  by  the  70-ampere  Su- 
prex,  and  the  7000  lumens  of  the  1  KW 
lamp. 

The    lamphouse    measures,    in    inches, 


35  long  x  24  wide  x  28  high,  which  large 
content  of  20,000  cubic  inches  combines 
with  the  forced  air  cooling  of  the  posi- 
tive carbon  feeding  mechanism  to  as- 
sure low  operating  temperatures  within 
the  lamphouse  even  when  burned  at  130 
amperes. 

Precise  Arc  Crater  Positioning 

The  position  of  the  positive  arc  crater 
is  automatically  maintained  at  the  exact 
focal  point  of  the  reflector  by  means  of 
Strong's  exclusive  Lightronic  crater  posi- 
tioning system.  The  positive  and  the 
negative  carbons  are  advanced  by  sepa- 
rate motors  the  speeds  of  which  are  gov- 
erned by  the  bi-metal  Lightronic  tube. 
Once  the  arc  has  been  struck,  the  crater 
positioning  and  the  arc-gap  length  are 
automatically  maintained  without  manual 
adjustment  or  any  further  attention  be- 
ing required. 

A  stream  of  air  directed  just  above  the 
arc  stabilizes  its  burning,  assures  com- 
plete combustion  of  any  black  soot,  and 
carries  away  the  white  smoke  which 
would  otherwise  be  deposited  on  the  re- 
flector. 

Optics:  WA-lnch,  F:1.9  Reflector 

The  optical  system  comprises  an 
eliptical  reflector  ^/-j"  in  diameter  with 
a  resultant  speed  of  F:1.9  to  match  the 
currently  available  high-speed  F:1.9  pro- 
jection lens.  The  mirror  and  its  tilting 
mechanism  are  an  integral  part  of  the 
back  door  of  the  lamphouse,  which 
swings  out  to  allow  easy  cleaning  of  the 
reflector  and  convenient  trimming  of  the 
lamp. 

The  Strong  Mighty  "90"  features  unit 
construction  whereby  the  various  com- 
ponents are  instantly  removable  for 
cleaning  and  inspection.  The  lamphouse 
is  finished  in  attractive  gunmetal  gray 
with  chrome  trim  and  weighs  165  pounds. 
There  is  an  arc  imager,  an  ammeter  for 
reading  the  current  at  the  arc,  an  auto- 
matic trimming  and  framing  light,  and 
an  inside  dowser  system. 


TWO  VIEWS  OF  STRONG  ELECTRIC  CORP.'S  NEW  'MIGHTY  90',  75-125  AMP.,  HIGH-INTENSITY,  REFLECTOR  ARC  LAMP 


At  the  left  is  shown  the  com- 
pletely enclosed  lamphouse, 
with  all  manual  controls 
visible.  The  right-hand  view 
shows  the  interior  of  the 
lamp,  with  the  16Vi-inch 
mirror  mounted  on  the  rear 
door  which  swings  open  for 
ease  of  trimming  and  gen- 
eral servicing.  Trim  posi- 
tioning, compact  feed  assem- 
bly, and  overall  sharpness 
of  design  lines  are  clearly 
evident. 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


15 


Questions  and  Answers  on  Projection  Lenses 


In  response  to  widespread  demand  from  our  readers  for  presentation  in  compact 
form,  the  appended  data  were  compiled  from  the  highly  informative  series  of  ads 
sponsored  by  Kollmorgen  Optical  Corp.  exclusively  in  IP  during  the  past  year. 


What  Is  the  Deposit  that 
Forms  on  Lens  Surfaces? 

This  deposit  may  be  dust,  fumes  from 
the  arclamp  housing,  or  oil.  Poor  venti- 
lation of  the  projector  or  projection 
room  will  probably  cause  a  deposit  to 
form  on  any  glass  surface  in  either  pro- 
jector or  room. 

What  Comprises  the  Coating  on 
Snaplite  Projection  Lenses? 

All  glass-to-air  surfaces  (all  surfaces 
except  the  cemented  ones)  are  coated 
with  a  thin  film  of  hard  magnesium- 
fluoride.  ; 

Just  What  Does  this  Coatinc  Do? 

The  coating  decreases  internal  reflec- 
tions and  increases  light  transmission  at 
each  surface.  By  practically  eliminating 
stray  light  it  improves  contrast,  brings 
out  colors  more  fully,  and  increases  the 
brightness  of  the  picture. 

How  Much  Brighter  Does  the  Lens 
Coating  Make  the  Picture? 

The  coating  increases  light  transmis- 
sion about  4%  per  lens  surface.  Thus 
the  Super-Snaplite,  having  eight  coated 
glass-to-air  surfaces,  transmits  about 
30%  more  light  than  would  a  similar 
lens  with  uncoated  surfaces. 

What  Causes  Coated  Lenses 
to  Become  Cloudy? 

The  magnesium-fluoride  coating  does 
not  cause  cloudiness,  but  it  might,  be- 
cause of  its  purple-straw  color,  make  the 
cloudiness  more  apparent.  Under  the 
same  conditions,  uncoated  lenses  will 
also  have  the  deposit. 

Why  Are  Short  Focal  Length  Lenses 
Used  for  drive-in  Theatres? 

Where  the  projection  room  must  be 
located  near  the  screen,  short-  ^focal 
length  lenses  are  necessary  to  project 
large  pictures.  For  this  reason  lenses 
with  focal  lengths  of  from  2  to  3V2 
inches  are  usually  used  in  drive-in  thea- 


tres. The  Kollmorgen  Screen  Chart 
shows  the  focal  length  needed  for  pic- 
tures from  9  to  85  feet  wide  at  from  40 
to  400  feet  projection  distance   (throw) . 

Do  Short  Focal  Length  Lenses 
Give  Hich-Quality  Pictures? 

Short  focal  length  lenses  for  wide- 
angle  projection  are  quite  difficult  to  de- 
sign, but  special  attention  to  this  phase 
in  computing  the  lens  results  in  an  effi- 
cient unit. 

Does  the  Picture  Projected  by  a 
Super-Snaplite  Have  the  Same 
Quality  at  All  Focal  Lengths? 

Yes.  Due  to  unique  design,  the  picture 
projected  by  a  2-inch  lens  shows  as  good 
definition,  flatness  of  field  and  uniformity 
of  light  as  with  the  more  popular  sizes, 
such  as  the  4-  or  4V2-inch  lenses. 

Are  the  Sizes  of  the  Various  Elements 
the  Same  for  All  Focal  Lengths? 

No;  the  elements  are  designed  speci- 
fically for  each  focal  length  and  vary  in 
size. 

What  Is  the  Tolerance  in  Focal 
Length  for  a  Good  Modern  Lens? 

A  good  modern  lens  should  be  within 
the  1%  plus-or-minus  tolerance  area  rec- 
ommended by  the  Society  of  Motion  Pic- 
ture Engineers. 

In  Actual  Practice,  What  Does 
This  Plus-or-Minus  1%  Mean? 

It  means  that  the  actual  picture  size 
for  any  focal  length  lens  will  be  within 
1%  plus-or-minus  of  the  computed  pic- 
ture size.  Thus,  if  a  20-foot  wide  picture 
(240  inches)  is  desired,  the  actual  pro- 
jected picture  might  be  238  or  242  inches 
and  still  fall  within  the  accepted  toler- 
ance. 

Does  the  F:1.9  Super-Snaplite 
Have  a  True  Speed  of  F.1.9? 

Yes,  in  all  sizes  from  2  inches  through 
4%  inches.  The  5-inch  size  has  a  speed 
of  F:  2.0. 


Two  pinhole 

apertures 
1  inch  apart 


Why  Does  the  5-Inch  Size  Differ  in 
Speed  from  the  Shorter  Focal  Lengths? 
This  is  due  to  the  limited  space  pro- 
vided in  some  projectors.  In  other  words, 
a  5-inch  lens  having  a  speed  of  F:1.9 
would  not  fit  into  some  present  projectors 
because  of  the  large  diameter  lens  barrel 
required. 

Does  the  Super-Snaplite 
Lens  Have  Diaphragms? 

No;  the  full  aperture  is  utilized  in  all 
focal  lengths. 

Does  a  Fast  Lens  Eliminate 
the  So-Called  'Hot  Spot'? 

Yes,  to  a  very  large  extent.  The  faster 
the  lens  and  the  higher  its  quality,  the 
more  uniform  will  be  the  screen  illumi- 
nation. 

Is  this  'Hot  Spot'  Worse  With 
Short  Focal  Length  Lenses? 

Usually.  The  falling-off  in  screen  illu- 
mination at  the  corners  can  be  quite  se- 
vere with  poor  lenses.  When  this  prob- 
lem is  given  full  consideration  in  the 
lens  design,  remarkably  even  screen  illu- 
mination is  achieved. 

If  the  Speed  of  an  Arclamp  Be  Slower 
Than  the  Lens,  Why  Use  a  Fast  Lens? 
This  topic  has  been  discussed  in  detail 
in  various  issues  of  IP,  including  an 
article  by  Dr.  J.  L.  Maulbetsch,  of  Koll- 
morgen Optical  Co.*  In  brief,  a  fast  lens 
gives  more  illumination  because,  having 
larger  lens  elements,  it  picks  up  more  of 
the  edge  illumination  than  does  a  slower 
lens  with  correspondingly  smaller  lens 
elements. 

Are  Adapters  Necessary 
for  Snaplite  Lenses? 

Fittings  are  available  to  adapt,  where 
necessary,  Snaplite  lenses  to  all  currently 
manufactured  professional  projectors. 

Are  Adapter  Drawings  Available? 

The  required  adapters  are  shown  in 
Kollmorgen  Bulletins  Nos.  204  and  206. 
Dimensions  of  all  adapters  except  the 
shade  tubes  are  fixed.  The  length  of 
the  shade  tube  varies  with  the  focal 
length  of  the  lens. 

How  Many  Lens  Elements  Are 
There  in  a  Super-Snaplite? 

Six:    two    pairs    of    elements    are    ce- 
{Continued   on   page   22) 

*  "Uniform   Screen  Illumination   as  Related   to  High- 
Speed   Lenses";   IP  for  September  1947,  p.  5. 


Pinhole  aperture 


P:2.5 


Showing  actual  optical  conditions  in  a  projector.    Note  that 
an  F:2.5  lens  does  not  match  an  F:2.5  mirror.  A  large  proportion  of 
the  light  from  the  illuminated  aperture  is  lost. 


f:2.5 


An  F:2.5  lens  "matched"  to  an  F:2.5  mirror — in  theory,  but  not 
as  conditions  exist  in  an  actual  projector. 


U 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


World  Series  Theatre  Tv  Evokes  Mixed  Reaction 


INDUSTRY  opinion  as  to  the  worth  of 
theatre  television  was  sharply  divided 
following  the  presentation  on  six  theatre 
screens  east  of  the  Mississippi  of  the 
World  Series  baseball  games,  which  in 
all  cases  augmented  the  regular  film  pro- 
gram. 

While  the  Tv  adherents  asserted  that 
the  telecasts  inaugurated  a  "new  era  of 
showmanship,"  the  skeptics  stressed  the 
fact  that  most  of  the  theatres  involved  in 
the  experiment  failed  to  pull  capacity  at- 
tendance. Preponderance  of  opinion  was 
that  all  future  theatre  Tv  events  must  be 
on  an  exclusive  basis  if  the  industry  is  to 
benefit  fully. 

A  city-by-city  roundup  of  the  series  re- 
ception, as  compiled  by  The  Film  Daily, 
is  appended: 

Brooklyn — Opening  day  attendance  in  ex- 
cess of  3,000  in  the  4100-seat  Fabian  Fox 
Theatre.  Attendance  fell  off  to  2,800  and 
2,400,  respectively,  on  second  and  third  day 
and  then  jumped  above  the  3,000  mark  for 
Saturday  and  Sunday.  Regular  55-cent  ad- 
mission was  increased  to  $1.25  during  the 
week,  and  $1.50  for  the  week-end.  Confection 
sales  quadrupled.    Reception  very  good. 

Boston — Patronage  at  the  1800-seat  Pil- 
grim Theater  for  the  five  days  hit  5,000,  with 
Saturday  the  biggest  draw.  Admissions  were 
scaled  at  $1.50  but  the  balcony  seats  at  85 
cents  failed  to  draw  and  were  discontinued. 
Management  expressed  disappointment  at 
the  returns  in  the  light  of  an  anticipated 
capacity  had  the  Red  Sox  been  in  the  series, 
but  were  optimistic  about  the  presentation 
of  future  televised  events. 

Chicago's  Intermediate  Showing 

Chicago — Upwards  of  10,000  saw  the  five 
games  at  the  B  &  K  State  Lake  Theater  at 
$1.25  scale.  This  was  the  only  house  in  the 
Paramount  intermediate  theater  tele  system 
which  puts  the  program  on  film  and  then 
projects  on  the  regular  screen.  Necessity  of 
bringing  the  film  over  from  the  Chicago  The- 
ater in  which  the  processing  equipment  is 
installed  was  responsible  for  several  breaks 
in  transmission  and  a  time  lag  of  20  minutes 
from  the  actual  action.  Special  announcers 
took  over  during  the  breaks  and  kept  the 
crowd  happy.  Many  patrons  inquired  as  to 
whether  football  games  would  be  shown  this 
Fall.  Opinion  around  Film  Row  is  that 
theater  Tv  is  here  to  stay,  and  while  the 
initial  expense  is  heavy,  ways  will  be  found 
to  share  them. 

Milwaukee — This  was  the  only  city  where 
the  series  was  available  on  two  screens. 
Both   houses,   the   Oriental  and   Tower,   are 


located  in  residential  districts,  several  miles 
from  downtown  first  run.  Tower  seats  1,585 
and  the  Oriental  2,200.  After  the  first  day 
when  transmission  bugs  were  responsible  for 
only  a  fair  image,  the  reception  was  highly 
satisfactory,  with  many  in  the  audience  re- 
porting it  superior  to  their  home  sets.  Aver- 
age attendance  approached  two-thirds  of  ca- 
pacity, with  the  best  grosses  on  the  final  day, 
Sunday.  Admission  price  at  both  houses  was 
$1.50.  Many  inquiries  were  received  by  the 
management  regarding  future  video  attrac- 
tions. 

Scranton — The  1,800-seat  West  Side  Thea- 
ter played  to  capacity  audiences  during  each 
of  the  five  games  telecast  here.  Admission 
price  was  only  30  cents,  however,  with  all 
profits  going  to  the  Community  Chest. 
*        *        * 

Par's  20-Second  Portable  Tv  Unit 

The  recent  convention  of  the  Theatre 
Owners  of  America,  held  in  Hollywood, 
saw  the  first  demonstration  of  the  new 


Paramount  portable  theatre  Tv  system 
which  allows  only  a  20-second  time  lapse 
between  the  appearance  of  the  Tv  signal 
on  the  tube  face  and  its  film  projection 
on  a  large  theatre  screen.  This  means 
that  Par  has  cut  its  processing  time  on 
such  film  by  35  seconds. 

Paramount's  determination  to  build  a 
nation-wide  system  of  Tv  station  affiliates 
was  emphasized  by  the  recent  announce- 
ment by  Station  KBTV  that  it  had  signed 
up  "as  the  first  affiliate  in  the  new,  up- 
and-coming  Paramount  Tv  network.  Sev- 
eral other  stations,  a  few  of  whom  are 
severing  connections  with  other  networks, 
will  sign  contracts  with  Paramount 
shortly,"  the  announcement  said. 

Paramount  intends,  it  was  said,  to  sup- 
ply its  station  affiliates  "with  the  best 
film  entertainment  yet  produced,  utilizing 
its  many  years  of  motion  picture  experi- 
ence, vast  production  facilities  and  large 

(Continued   on   page   24) 


CHICAGO   LOCAL    110   BUILDS  CRAFT   PRESTIGE:   TRIBUTE   BY  TV   EXECUTIVE 


Tv  equipment  shown,  from   left  to  right:  line  amplifier,  monitoring   oscilloscope,  and 
control  console.     Local  110  members  handled  this  equipment. 


Only  the  foresight  of  this  progressive 
organization,  under  the  leadership  of 
Gene  Atkinson  and  his  able  associates, 
enabled  the  publication  of  this  very 
significant  picture  in  which  are  shown 
projectionists  who  work  under  con- 
tracts signed  long  before  television 
developed  its  present  imposing  stature. 
Seen  here  are  Joseph  Hovorka, 
Bobby  Burns  and  Ira  Jacobson,  all 
members  of  Local  110,  on  the  occa- 
sion of  the  transmittal  of  Tv  images 
to  the  assemblage  at  the  recent  joint 


TESMA-TEDA  convention  in  Chicago. 
Said  Barton  Kreuzer,  manager  of 
RCA's  Theatre  and  Film  Recording 
Department : 

"I  confess  that  it  was  not  without 
some  misgiving  that  I  entrusted  the 
first  showings  of  television  to  men 
who,  I  imagined,  were  not  too  well 
versed  in  the  niceties  of  this  exacting 
art.  However,  I  want  to  say  to  this 
assemblage  that  the  success  of  this 
demonstration  here  today  is  due  in  no 
small  measure  to  the  ability  and  sea- 
soned experience  of  these  craftsmen." 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


17 


By 

HARRY 

SHERMAN 


THAT  workers  in  all  crafts  are  more 
interested  in  some  form  of  security 
after  a  given  number  of  years'  work 
rather  than  peak  current  wages  was 
brought  home  sharply  to  us  in  recent 
trips  about  the  country  during  which  we 
got  together  with  several  groups  of  our 
fellows  and,  as  usual,  talked  a  little 
"'shop."  The  important  point  here,  we 
think,  is  that  these  various  groups  were 
not  composed  largely  of  old-timers  who 
might  be  expected  to  bear  down  heavily 
on  the  security  angle,  but  included  men 
whose  craft  service  ranged  from  eight 
years  upward. 

Naturally  the  talk  got  around  to  the 
Chicago  Local  110  pension  plan,  and 
there  was  general  agreement  that  this 
set-up  with  its  various  benefits  was  a 
fine  thing,  particularly  for  the  oldster 
who  wished  to  retire.  But  there  was  other 
talk,  too,  which  was  not  so  pleasant  and 
not  so  favorable  to  the  worker,  old 
or  young. 

There  was  talk,  for  instance,  of  the 
various  "pension"  plans  instituted  by 
various  circuits  which  ran  along  for 
years  and  then  blew  up  right  in  the  work- 
ers' faces  when  the  theatre  was  sold  or 
the  circuit  decided  to  "make  a  change" 
or  some  such  stuff.  There  was  talk,  too, 
about  the  classic  case  where  a  man  who 
worked  in  one  theatre  for  30  years  was 
forced  to  retire  due  to  failing  eyesight — 
and  the  theatre  gave  him  one  week's  sal- 
ary as  severance  pay! 

Mention  was  made  in  one  session  that 
in  the  absence  of  any  concrete  security 
provision,  projectionists  should  benefit 
by  a  profit-sharing  plan  under  which  a 
part  of  the  profits  would  be  set  aside 
either  for  periodical  distribution  or  for 
deposit  to  individual  accounts  and  dis- 
tribution contingent  upon  retirement,  dis- 
ability, severance  or  some  other  condi- 
tion. There  has  been  very  little  thought 
given  by  the  craft  to  a  profit-sharing 
plan,  probably  because  projectionists  do 
not  actually  produce  anything  in  the 
same  sense  that  a  factory  worker  does 
but  rather  is  regarded  as  one  who  ren- 
ders service. 

Upon  returning  home  from  our  most 
recent  trip,  we  got  to  thinking  about  this 
profit-sharing  idea  and  did  a  little  dig- 


ging by  getting  some  data  from  the  Na- 
tional Industrial  Conference  Board  and 
the  Council  of  Profit-Sharing  Industries, 
which  we  pass  along  here. 

We  were  surprised  to  learn  that   not 

BUSINESS  AGENT  FOR  25  YEARS 


Bill  Hartnett  (center)  is  given  the  keys  to  a 
sleek  new  Dodge  sedan  in  recognition  of  his 
25  years  of  service  to  Ottawa,  Can.,  Local  257. 
At  left  is  A.  B.  Zumar,  sec.-treas.,  and  (right) 
James  McGuire,  pres.,  of  L.  257. 

only  are  profit-sharing  plans  spreading 
rapidly  in  various  industries  but  also 
that  executives  of  companies  having  such 
plans   are,   as   one  report   states,    "over- 


whelmingly enthusiastic"  about  their 
benefits  to  both  the  companies  and  work- 
ers. An  idea  of  how  rapidly  such  plans 
are  growing  may  be  had  from  the  fact 
that  in  some  localities  banks  are  actively 
competing  for  the  business  of  handling 
the  trust  funds. 

Several  of  the  reports  at  hand  mention 
the  fact  that  in  past  years  unions  were 
strongly  opposed  to  any  profit-sharing 
plan,  the  most  effort  being  exerted  in 
getting  the  highest  wages  possible.  The 
growing  concentration  by  unions  on  some 
form  of  security  for  their  members  is  re- 
flected by  the  fact  that  at  the  present 
time  "union  opposition  to  profit-sharing 
has  largely  evaporated";  in  fact,  certain 
units  of  both  the  A.  F.  of  L.  and  CIO 
now  insist  upon  writing  the  profit-sharing 
arrangement  into  the  labor  contract. 

Here  are  a  couple  of  typical  comments 
by  executives  of  companies  which  have 
profit-sharing  plans  in  operation: 

A.  R.  Meeker,  president,  Meeker  Mimeo- 
graph Co.,  Newark :  "In  my  opinion,  the  chief 
advantage  is  that  the  employes  do  develop 
a  feeling  of  really  belonging  to  the  organi- 
zation and  a  sense  of  ownership  and  respon- 
sibility. With  this  feeling  prevalent  a  mini- 
mum of  supervision  is  required.  *  *   *  Over 


IA  STATE  CONFERENCE  AT  ILLINOIS  FEDERATION  OF  LABOR  CONVENTION 


Seated:  Earl  J.  McMahon,  secretary,  Illinois  Federation  of  Labor;  Felix  D.  Snow,  6th  IA  vice- 
president;  IA  President  Richard  Walsh;  Frank  Stickling  and  William  Donnelly,  IA  representatives; 
John  H.  Wald,  9th  District  secretary  and  also  secretary  of  Illinois  State  Conference. 

Standing:  Sam  Bonansinga,  president,  Springfield  Local  138  and  vice-president.  III.  State 
F.  of  L.;  W.  F.  Wepner,  secretary,  Springfield  Local  323;  Tony  Stuches,  business  representative, 
and  C.  A.  Wallace,  president.  Local  323.  Next  are  Conference  Board  members  with  their'  IA 
Local  designations:  Fred  Shoup,  Bloomington,  193;  Ray  McNickle,  E.  St.  Louis,  288;  S.  Lamasky, 
Chicago,  B-45;  R.  Engel,  Galesburg,  166;  then  L.  C.   Brownlow,  323,  Federation  delegate. 


18 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


BEAUTY,  UTILITY  IN  FLORIDA  PARADE 

iWEKi 


Labor  Day  float  of   Fort  Lauderdale   IA   Local 

646    presents    pretty    girls    watching    a    screen 

show,  ushers  standing   in   attendance,  and   the 

projectionist,  C.  W.  Goethe. 

the  years  we  have  gotten  cooperation  and 
teamwork  to  a  remarkable  degree." 

D.  R.  Thompson,  secretary,  the  Snow- 
Nabstedt  Gear  Corporation,  Hamden,  Conn.: 
"Our  plan  has  been  in  continuous  operation, 
in  good  times  and  bad,  for  a  period  of 
twenty-six  years,  and  we  feel  that  it  has 
been  one  of  the  greatest  single  factors  in  our 
pleasant  personnel   relationship." 

Whether  profit-sharing  is  feasible  for 
projectionist  organizations  because  of  the 
nature  of  the  service  they  render  is  a 
very  difficult  question  to  answer  and 
one  that  would  require  a  lot  of  straight 
thinking  and  planning.  But  we  do  know 
that  the  operation  of  the  Local  110  pen- 
sion plan  has  set  local  union  leaders  all 
over  the  country  to  thinking  about  some 
form  of  security  for  their  members. 


Do  you  remember  when  paid  vacations 
for  projectionists  was  a  revolutionary 
idea? 

If  union  leaders  run  into  a  stone  wall 
in  their  efforts  to  establish  a  security 
program  in  one  form  or  another,  they 
might  consider  going  after  some  profit- 
sharing  plan.  If  the  foregoing  para- 
graphs set  the  thinking  wheels  turning 
along  the  lines  of  benefit  plans,  they  will 
have  well  served  their  purpose. 

•  The  IA  General  Office  recently  an- 
nounced the  signing  of  three-year  con- 
tracts, retroactive  to  August  6,  1948,  for 
1000  Philadelphia  movie  theatre  work- 
ers, members  of  Local  B-100.  who  last 
Spring  rejected  a  bid  to  jump  to  John  L. 
Lewis'  District  50.  United  Mine  Workers. 
In  addition  to  pay  increases,  the  contracts 
provide  a  week's  vacation  with  pay  for 
all  employed  over  one  year  and  who  work 
18  hours  or  more  per  week;  those  em- 
ployed over  five  years  get  two  weeks 
paid  vacations.  These  contracts  affect 
employes  of  the  Warner.  Paramount  and 
Fox  circuits,  and  the  Theatre  Cleaning 
Service. 

•  California  District  No.  2  will  hold  its 
1950  meeting  in  Hollywood,  with  Local 
165  acting  as  host  to  the  delegates. 

•  The  Museum  of  Modern  Art  in  New 
York  City  was  the  scene  of  a  party  spon- 
sored by  Local  306  officials  in  honor  of 
Steve  D'Inzillo,  business  representative. 
President  Herman  Gelber  was  master  of 
ceremonies,    with    Harry    Storin,    Ernie 


QUANTITY,  QUALITY  THROUGH  THE  YEARS 


CALIFORNIA  DISTRICT  COUNCIL  NO.  2  HOLDS  ANNUAL  MEETING  IN  SAN  BERNARDINO 


=:!*^T§1 


San  Bernardino  Local  577  and  Barstow  Local  730  entertain  District  No.  2  delegates  at  a  beef- 
steak dinner.  Seated,  left  to  right:  Robert  Bennett,  bus.  rep.  San  Bernardino  L.  577;  Ralph 
Adams,  District  Council  vice-pres.  and  bus.  rep.  Santa  Ana  L.  504;  Carl  Cooper,  International 
7th  vice-pres.;  Wm.  Wise,  Council  pres.;  Alonzo  Bennett,  Council  sec.-treos.  and  sec.-treas.  Long 
Beach  L.  521;  Harry  Beauford,  bus.  rep.,  J.  O.  Jones,  pres.  and  Rudy  Trotter,  sec.-treas.,  all  of 
Barstow  L.  730. 

Standing,  left  to  right:  Charles  Collins,  pres.  San  Diego  L.  297;  Stanley  Campbell,  bus.  rep. 
Hollywood  L.  706;  Walter  McCormick,  pres.  Hollywood  L.  165;  John  Lehners,  bus.  rep.  Los  An- 
geles L.  776;  Earl  Hamilton,  pres.  Los  Angeles  L.  150;  Herb.  Aller,  bus.  rep.  Hollywood  L.  659; 
Norman  Morris,  bus.  rep.  El  Centro  L.  656;  Chas.  Vencill,  sec.-treas.  and  Magnus  Nielsen,  bus. 
rep.  of  Los  Angeles  L.  150;  W.  L.  Coleman,  sec.-treas.  and  Art  Narath,  pres.  of  Santa  Ana  L. 
504;  Chas.  Baumgartner,  sec.-treas.  and  Wm.  Romley,  bus.  rep.  of  Bakersfield  L.  215;  Basil  Davis, 
pres.  and  Harry  Reynolds,  chairman,  Wage  Scale  Com.  San  Bernardino  L.  577;  L.  S.  Hall,  bus. 
rep.  San  Diego  L.  297;  Max  Miller,  pres.  Long  Beach  L.  521;  John  Gotchell,  sec.-treas.  Santa 
Barbara  L.  442;  W.  Caplan,  sec.-treas.  Hollywood  L.  705;  and  Cecil  Walters,  bus.  rep.  L.  294, 
Phoenix,  Ariz.    The  meeting  was  voted  the  best  Council  gathering  ever. 


Ted  Bowers,  business  agent  of  IA  Local  64, 
Wheeling,  W.  Va.,  the  father  of  13  children 
of  whom  5  sons  belong  to  L.  64.  This  picture 
forwarded  by  Al  Boudouris  of  Theatre  Equip- 
ment Co.,   Toledo. 

Lang,  Harry  Garfman,  Izzy  Schwartz. 
Ben  Scher  and  Frank  Inciardi  serving 
on  the  arrangements  committee. 

•  Congratulations  to  Bert  Steinhauser. 
business  representative  of  Local  373, 
Terre  Haute,  Ind.,  on  his  re-election  to 
office  for  his  20th  consecutive  term. 

•  Allen  G.  Smith,  National  Theatre  Sup- 
ply Co.'s  popular  New  York  branch  man- 
ager, recently  underwent  minor  surgery 
at  the  Wickersham  Hospital.  Allen  is 
feeling  pretty  slick  again  and  from  sub 
rosa  reports  reaching  this  corner  he  seems 
to  have  been  completely  rejuvenated. 

•  Milwaukee  Local  164  was  well  rep- 
resented at  the  recent  TESMA-TEDA 
meeting  in  Chicago.  Particularly  inter- 
ested in  the  RCA  tele  demonstration  were 
Glen  Kalkhoff,  pres.;  Oscar  E.  Olson, 
bus.  rep. ;  George  Beck,  Karl  Miller,  Myrl 
Melton,  Alex  Zebe,  Rudy  Willert,  Karl 
Fergens,  Harry  Post,  Charles  Herbst. 
Frank  Wagner,  and  Henry  Putsear. 

•  Lou  Walters,  former  district  manager 
for  Ampro  Corp.,  has  given  up  the  thea- 
tre supply  business  and  joined  the  ranks 
of  projectionists.  His  application  for 
membership  in  Dallas  Local  249  was  ap- 
proved last  month  and  he  now  is  working 
at  the  Kaufman  Pike  Drive-In  Theatre. 
We  are  sure  that  Lou  will  prove  a  valu- 
able member  to  Local  249,  and  we  wish 
him  lots  of  luck  in  his  new  calling. 

•  Many  IA  Local  Unions  were  repre- 
sented at  the  recent  Connecticut  State 
Federation  of  Labor  Convention,  which 
was  held  at  the  Hotel  Garde  in  New 
Haven.  Mike  Scanlon,  business  repre- 
sentative of  Torrington  Local  402,  and 
Frank  Corrigan,  business  representative. 
Waterbury  Local  88,  were  candidates  for 
the  office  of  Federation  vice-president. 

Other  IA  delegates  were  John  Martin. 
Bridgeport  Local  277;  Charles  North. 
Hartford  Local  486 ;  John  McGlew,  Meri- 
den  Local  350 ;  Rube  K.  Lewis,  Hartford 
Local  84;  James  Corrigan  and  Frank 
Carey.  Waterbury  Local  304;  Matt  Ken- 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


19 


nedy,  New  Haven  Local  273;  Fred  No- 
well,  New  London  Local  439;  Joe  Tas- 
sinero,  Bridgeport  Local  109;  Fred  Ma- 
thews, New  Britain  Local  301 ;  John  Mil- 
ler, New  Haven  Local  74,  and  Irving  C. 
Lown,  Danbury  Local  662. 

•  James  A.  Whitebone,  secretary  and 
business  representative  for  Local  440, 
St.  John,  N.  B.,  has  been  re-elected  to 
serve  his  16th  term  as  president  of  the 
New  Brunswick  Federation  of  Labor. 
Whitebone  has  rounded  out  more  than 
20  years  of  service  as  an  official  of  Local 
440,  during  which  time  he  has  become 
known  throughout  the  Alliance  as  a 
very  able  and  conscientious  labor  leader. 

•  Another  chest-puffer  for  cause :  Joe  De 
Renzis,  business  agent  for  Local  710, 
Stroudsburg,  Penna.,  is  broadcasting  on 
an  ultra-high  wavelength  about  the  new- 
comer to  his  home.   Heir  or  heiress,  Joe? 

•  The  25-30  Club  of  New  York  City 
launched  its  1949-50  season  with  one  of 
the  best  meetings  in  its  history,  from  the 
standpoint  of  attendance  and  proceed- 
ings. The  great  turnout  of  members  were 
given  a  rare  treat  by  the  appearance  of 
J.  A.  Fetherston,  sales  manager  of  the 
Kollmorgen  Optical  Corp.,  who  gave  a 
candid  and  no-holds-barred  presentation 
of  modern  projection  optics.  More  such 
sessions  on  a  wider  scale  throughout  the 
country  would  benefit  the  craft. 

Cecil  R.  Wood,  St.,  got  off  to  a  fast 
start  for  his  presidential  year,  and  it 
evoked  a  flood  of  memories  to  see  this 
old-timer  in  the  craft  do  his  stuff. 

•  Sad  news  occasionally  breaks  into  these 
columns,  such  as  the  recent  death  of  Flo 
Jackson,  wife  of  Howard  Jackson,  busi- 
ness representative  of  Local  343,  Omaha, 
Nebr.    Mrs.  Jackson  came  from  a  well- 


AT  ALTEC'S  12TH  ANNIVERSARY  PARTY 


No  exchange  of  weighty  topics  but  good  fellow- 
ship is  evidenced  by  this  shot  of  Altecmen  D.  L. 
Netter,  Jr.,  C.  S.  Perkins  and  Harold  Wengler, 
and,  second  from   right,  Harry  Sherman  of  IP. 

known  theatrical  family  and  was  known 
professionally  as  Flo  LaDell.  She  accom- 
panied Howard  to  many  IA  gatherings 
and  was  known  to  many  of  the  old-timers. 
We  sympathize  deeply  with  Howard  in 
his  loss. 

•  The  Illinois  State  Conference  meeting 
was  held  in  Springfield  last  month  in  con- 
junction with  the  Illinois  State  Federa- 
tion of  Labor  Convention.  Frank  Stick- 
ling, IA  representative  of  the  9th  District, 
presided.  The  Conference  meeting  closed 
with  a  party  tendered  the  delegates  and 
guests  at  the  Elks  Club.  Committees  ap- 
pointed by  Springfield  Locals  323  and 
138  were  in  charge  of  arrangements. 

•  Charbe  Keeler  was  elected  business 
representative  for  Local  597,  Waco,  Tex- 
as, succeeding  Bob  Foster,  who  resigned 
because  of  ill  health. 

•  We  were  looking  forward  to  a  meeting 
with  our  good  friend  Vern  Harris,  former 


secretary  of  Toledo  Local  228,  who 
planned  to  visit  the  IP  offices  while  on  a 
vacation  trip.  Then  we  received  word 
from  him  advising  us  of  a  rather  un- 
pleasant experience  he  had.  Vern's  car 
was  broken  into  while  visiting  friends  in 
Camden,  N.  J.,  en  route  to  New  York, 
and  all  of  his  and  Mrs.  Harris'  belong- 
ings were  stolen.  Not  a  very  pleasant 
ending  to  an  anticipated  pleasure  trip. 

•  A  salute  to  the  officials  of  Local  350, 
Meriden,  Conn.,  for  their  effective  picket- 
ing of  a  non-union  house.  Several  weeks 
of  intensive  picketing  of  the  new  Meri- 
den Theatre,  which  opened  last  August 
with  non-union  projectionists,  resulted 
in  the  signing  of  an  agreement  with 
Local  350. 

•  Roy  Brewer,  IA  West  Coast  representa- 
tive, was  unanimously  re-elected  chair- 
man of  the  AFL  Hollywood  Film  Coun- 
cil, which  represents  about  20,000  studio 
employes. 

•  Pittsburgh  Local  171  celebrated  its 
40th  anniversary  with  a  banquet  on  Sep- 
tember 20  last.  President  Walsh,  Secre- 
tary Raoul,  and  other  top  IA  officials 
were  present  at  the  affair.  Mayor  Law- 
rence of  Pittsburgh  and  a  number  of 
prominent  civic  leaders  were  among  the 
invited  guests  present. 

On  behalf  of  Local  171,  President 
Walsh  presented  two  charter  members, 
Clyde  Cain  and  Arthur  G.  Williams,  with 
gold  wrist  watches. 

•  New  York  Local  306  television  classes 
for  the  1949-50  season  opened  September 
19  last  with  a  high  registration.  Regis- 
trants are  required  to  attend  classes  three 
days  per  week — either  from  9  to  11  a.m., 
or  from  12  noon  to  2  p.m.  Beginners  are 

(Continued  on  page  29) 


RCA  THEATRE  SUPPLY  DEALERS  HOLD  ANNUAL  MEETING  AT  RECENT  CHICAGO  TESMA-TEDA  CONVENTION 


Dealers  in  RCA  theatre  supplies  from  all  parts  of  the  country  attending  the  annual  dealer  meeting  conducted  by  the  RCA  Theatre  Equipment  Sec- 
tion in  conjunction  with  the  TESMA-TEDA  convention  at  the  Hotel  Stevens  in  Chicago.  Front  row,  left  to  right:  John  Volkman  and  Duncan  Phyfe, 
RCA  theatre  equipment  engineers;  Jack  O'Brien,  manager,  Theatre  Equipment  Section;  Karl  Brenkert,  president,  Brenkert  Light  Projection  Co. 
(RCA  subsidiary);  Homer  B.  Snook,  president.  Midwest  Theatre  Supply  Co.,  Cincinnati;  Charles  R.  Underbill,  Jr.,  and  Ralph  H.  Heacock,  theatre 
equipment  sales. 

To  the  right  of  the  aisle  in  the  second  row,  left  to  right:  Barton  Kreuzer,  head  of  RCA's  Theatre  and  Film  Recording  Dept.;  W.  W.  Watts, 
vice-president  in  charge  of  Engineering  Products  Dept.;  T.  A.  Smith,  general  sales  manager;  Arch  Hosier,  St.  Louis  Theatre  Supply  Co.;  C.  F. 
Strawley  and  Herman  Henken,  Theatre  Equipment  Section;  J.  V.  Buckley,  J.  Walter  Thompson  Co.;  Richard  Sanderson,  Theatre  Equipment  Section. 


20 


INTERNATIONAL  PROJECTIONIST 


October  1949 


The  Origins  of  the  'Magic  Lantern' + 

The  second  instalment  of  an  article  which  traces  the  development  of  the  modern  slide 
projector  out  of  the  old  art  of  "mirror-writing,"  a  derivation  of  the  silhouette. 


By  J.  VOSKUIL 

Research  Chemist,  Gcldermalsen,  Holland 

IT  MAY  be  imagined  that  the  develop- 
ment of  the  magic  lantern  from  the 
camera  obscura  had  taken  place  after 
systematic  research  work  on  geometrical 
optics,  as  is  the  practice  today.  By  mov- 
ing the  object  from  a  point  far  off  to 
the  focus  of  the  lens,  and  by  construct- 
ing a  device  for  optical  lighting  (con- 
denser), which  is  a  characteristic  feature 
in  a  projector,  one  had  changed  the 
camera  obscura  into  a  magic  lantern. 

But  in  Porta's  time  there  was  no  ques- 
tion of  systematic  research.  All  investi- 
gation was  more  or  less  guesswork,  done 
for  the  greater  part  by  adventurers  and 
charlatans  who  looked  for  ways  in  which 
to  deceive  the  credulous  public  and  to 
make  quick  money.  As  for  the  very  small 
scientific  world  of  those  days,  it  was 
interested  only  in  the  magnifying  power 
of  lenses  and  their  use  in  microscopes 
(Hooke  van  Leeuwenhoek)  and  telescopes 
(Galileo). 

Genesis  of  Optic  Projection 

So  the  principles  of  optic  projection 
were  invented  by  way  of  trial  and  error, 
and  in  the  previously-mentioned  first 
edition  of  Kircher's  "Ars  Magna"  of  1646 
we  can  find  a  good  starting  point  for  the 
historical  development  of  the  slide  pro- 
jector, for  on  pages  907-917  we  read 
about  experiments  which,  traced  back- 
ward, point  to  the  "silhouette  show,"  and 
on  the  other  side  directly  lead  to  the 
first  magic  lanterns  of  Christiaan  Huy- 
gens  (1629-1695)  and  Thomas  Walgen- 
sten. 

Kircher,  who  was  at  that  time  in  Rome, 
carried  out  these  experiments  because  he 
was  fascinated  by  the  old  "art  of  mirror- 
writing."  From  passages  in  Agrippa 
von  Nettesheim's  works  on  occult  phi- 
losophy (16th  Century)  we  learn  that 
this  art  is  very  old,  even  the  name  of 
Pythagoras  (500  B.  C.)  being  connected 
with  it. 

The  ancients  seem  to  have  experi- 
mented with  a  system  of  long-distance 
communication  by  writing  on  a  plane  or 
concave  mirror  which  was  reflected  on  a 
screen  placed  at  some  distance.  Thus  a 
kind  of  optical  telegraphy  was  con- 
structed to  be  used  for  messages  to  army 
leaders  in  battle  or  for  other  emergencies. 

Von  Nettesheim  tells  us  the  fantastic 
story  that  Pythagoras,  while  in  Italy,  in 
this  way  communicated  with  his  friends 
in  Byzantium.    He  wrote  the  letters  with 


his  blood  and  reflected  the  mirror  to  .  .  . 
the  moon! 

Figure  3,  b  and  c,  shows  schematically 
how  the  ancients  planned — and  perhaps 
put  into  practice — their  "art."  On  a 
mirror,  Sp,  the  reversed  letters,  /,  were 
traced;  these  did  not  reflect  the  rays  of 
the  sun  and  thus  formed  shadowy  figures 
on  a  screen,  5,  as  reflected  by  the  mirror. 
In  fact,  mirror-writing  really  is  nothing 
but  using  a  mirror  to  direct  a  certain 
shadow,  A,  to  a  certain  spot,  b.  By  using 
a  concave  mirror  the  ancients  tried  to 
get  larger  images,  c. 


We  learn  in  the  primers  on  optics  that 
the  shadow  of  an  object  lighted  by  a 
light  of  some  dimensions  becomes  less 
sharp  as  the  distance  between  the  object 
and  the  screen  grows.  The  inner  shadow 
grows  narrower  and  the  penumbra  broad- 
er. Consequently,  the  reflected  writings 
are  somewhat  blurred  at  relatively  small 
distance  and  badly  blurred  at  greater 
distance. 

Kircher's  Use  of  a  'Lens' 

Now,  Kircher  tried  to  improve  on  this 
method  by  means  of  a  lens.  That  he 
chose  a  lens  was  very  probably  not  the 
result  of  scientific  reflections  but  of  the 
fact  that  the  lens,  as  an  optical  imple- 
ment, was  becoming  ever  more  popular. 
The  17th  Century,  in  which  Kircher  lived, 
(Continued   on    page    25) 


FIG.  3.    Development  of  modern  projection  systems  from  the  silhouette: 

v  r=  object;  s  =  screen;  /  =  source  of  light;  la  =  slide;  fi  =  film;  sp  =  mirror;  and  o,  le,  co  = 

lens  (o  as  objective,  co  as  condenser). 


fj.   Soc.   M.  P.  Eng.,  Dec,  1948. 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


21 


QUESTIONS  AND  ANSWERS 
ON  PROJECTION  LENSES 

(Continued  from  page  16) 

mented  together,  and  two  elements  are 
single. 

Are  the  Cemented  Surfaces  Coated? 

No.  Treating  cemented  surfaces  with 
an  anti-reflection  coating  would  not  in- 
crease the  light  transmission  of  the  lens. 

Are  Snaplite  Lenses  Sealed, 
and  If  So,  How? 

All  Snaplite  Series  II  and  Super-Snap- 
lite  lenses  manufactured  since  January 
1946  are  of  sealed  construction  to  pre- 
vent entrance  of  moisture,  dust  or  oil. 
This  is  accomplished  by  using  a  one- 
piece  lens  barrel  made  from  a  solid  bar 
with  no  threaded  joints.  The  front  and 
the  rear  elements  are  sealed  by  means 
of  synthetic  rubber  gaskets. 

Should  Sealed  Lenses  Be  Taken  Apart? 
No,  never  disassemble  a  sealed  lens. 
If  there  develops  any  indication  that  the 
lens  need  be  taken  apart,  it  should  be 
returned  to  the  factory  for  complete  ex- 
amination. 

Why  Is  Aluminum  Used 
for  Lens  Mounts? 

Because  of  its  light  weight,  high- 
strength  aluminum  alloy  is  preferred  to 


brass  for  lens  mounts,  especially  if  the 
former  is  protected  by  anodizing.  A  gold 
anodized  finish  is  used  for  Super-Snap- 
lites,  while  a  black  finish  is  used  for  the 
Series  I  and  II  lenses. 

Are  Plastic  Mounts  Used  in 
Snaplite  Lenses? 

Definitely  not.  The  black  anodized 
aluminum  barrel  has  sometimes  been 
mistaken  for  plastic;  but  we  do  not  con- 
sider plastics  as  being  suitable  for  mount- 
ing high- precision  lenses. 

How  Is  It  Possible  to  Get  a  Blurred 
Picture  With  a  Good  Lens? 

This  is  usually  caused  either  by  mis- 
alignment of  the  entire  optical  system  of 
the  projector  or  by  the  lens  itself  not 
being  securely  held. 

Must  Fast  Lenses  Be  Aligned  More 
Accurately  Than  Slower  Ones? 

Yes.  An  extremely  fast  lens  must  be 
held  securely  at  all  times.  The  lamp,  pro- 
jector and  lens  must  be  kept  in  align- 
ment. Check  by  interchanging  lenses 
between  projectors. 

Should  Lenses  Be  Replaced  in  Holders 
in  the  Same  Position  Every  Time? 

This  is  not  necessary  in  the  case  of 
Snaplites,  which  are  so  centered  that  no 
alignment   marks   are   necessary. 

How  Often  Should  Focus  Be  Checked? 
The  focus  should  be   checked  at  fre- 


Mirror  rated  J* : 2. 5 


ANSWER 
TO  YOUR 
TECHNICAL 
PROBLEMS . . . 


The  Altec 
Service  Man  and 
the  organization 
behind  him 


F:1.5 


Optics    matched 
Condenser  rated  f  :2.5 


x    \ 


F-.1.5 


l6l  Sixth  Avenue, 
New  York  13,  N.  Y. 

PROTECTING  THE  THEATRE—FIRST  PLACE  IN  ENTERTAINMENT 


Optics  not  matched 
in  this  case 

Example:  a   projection   lens  which   is  matched 
to  one  lamp  is  not  necessarily  matched  to  an- 
other lamp  having  the  same  "speed". 

quent  intervals,  especially  after  reels  are 
changed.  If  after  checking  focus,  align- 
ment and  lens  holder,  the  lenses  do  not 
give  a  good  picture,  they  should  be  re- 
turned for  inspection. 

How  Should  Coated  Lenses  Be  Cleaned? 
Instructions  on  the  care  of  both  coated 
and  uncoated  lenses  are  generally  avail- 
able from  either  supply  dealers  or  manu- 
facturers. Form  66  is  the  Kollmorgen 
designation  for  these  data. 

Altec  Takes  Over  W.  E.  Sound 
Reproducing  Activities 

Altec  Lansing  Corp.  will  take  over 
Western  Electric's  commercial  activities 
in  microphones,  loudspeakers  and  disc 
reproducing  equipment  under  an  agree- 
ment entered  into  by  the  two  companies, 
according  to  an  announcement  by  F.  R. 
Lack,  vice-president  of  W.  E.  The  agree- 
ment, which  is  already  in  effect,  will 
assure  uninterrupted  service  and  availa- 
bility of  maintenance  parts,  Lack  said. 
Cited  among  the  reasons  for  W.  E.'s  deci- 
sion to  withdraw  from  the  field  were  the 
continuing  specialized  needs  of  the  Bell 
Telephone  System  and  the  expanding  re- 
quirements of  the  armed  forces  for  the 
development  of  complex  electronic  equip- 
ment essential   to   the   nation's   defense. 

Distribution  Continues  Thru  Graybar 

Graybar  Electric  Co.  will  act  as  dis- 
tributor for  Altec,  as  it  has  for  W.  E.,  in 
the  sale  and  servicing  of  the  type  of 
equipment  concerned.  Among  the  prod- 
ucts affected  will  be  the  109  reproducer 
series,  the  633  and  639  types  of  micro- 
phones, and  the  728,  755  and  757  types  of 
loudspeakers  used  extensively  in  broad- 
casting and  high-quality  sound  system 
applications. 

Altec  was  founded  in  1937  to  carry  on 
the  theatre  servicing  activities  of  Electri- 
cal Research  Products,  Inc.,  at  that  time 
a  subsidiary  of  W.  E. 

Commenting  on  the  W.  E.  announce- 
ment, G.  L.  Carrington,  president  of  the 
Altec  companies,  said: 

"This  development  will  enable  both 
Altec  Service  and  Altec  Lansing  to  round 


22 


INTERNATIONAL  PROJECTIONIST 


October  1949 


out  and  expand  their  interacting  activi- 
ties, not  only  in  the  motion  picture  field 
but  in  the  audio  industry  generally.  The 
addition  of  these  splendid  W.  E.  prod- 
ucts to  our  present  line  of  sound  appa- 
ratus enables  Altec  to  supply  all  branches 
of  the  audio  industry  with  their  essential 
technical  equipment." 

TESMA-TEDA  Convention  Tops 

Three  thousand  people.  87  companies 
occupying  110  booths  for  the  display  of 
every  conceivable  product  which  consti- 
tutes the  modern  motion  picture  theatre, 
a  flood  of  confidences  and  conviviality 
marked  the  1949  joint  convention  of 
TESMA  (Theatre  Equipment  Supply 
Manufacturers  Association)  and  TEDA 
(Theatre  Equipment  Dealers  Associa- 
tion) held  in  Chicago  the  last  week  in 
September. 

Evidence  that  "the  show's  the  thing" 
is  no  longer  "gospel"  was  abundant  on 
all  sides  as  for  the  first  time  in  motion 
picture  history  mere  incidentals  to  the 
presentation  of  a  picture  on  a  screen 
far  outnumbered  the  purely  technical  and 
time-honored  units  devised  for  the  show- 
ing of  motion  pictures.  Popcorn?  Yes. 
multiplied    manifoldly. 

The  spirit  of  the  gathering  over-all 
seemed  to  be  that  if  the  theatre  were  kept 
appealing  in  terms  of  a  community  cen- 
ter, with  convenient  and  eye-appealing 
appointments  playing  a  major  part  in 
gaining  and  holding  such  prestige,  the 
movies  had  very  little  to  worry  about  in 
terms  of  competitive  amusements — in- 
cluding television  with  a  capital  T. 

Oscar  F.  Neu,  president  of  Neumade  Prod- 
ucts Corp.,  was  re-elected  president  ot 
TESMA.  J.  R.  Hoff,  Ballantyne  Co.,  was 
elected  vice-president,  and  Roy  Boomer  was 
re-elected    secretary    and    treasurer. 

Named  to  the  board  of  directors  were: 
L.  W.  Davee,  Century  Projector  Corp.; 
H.  B.  Engel,  GoldE  Mfg.  Co.;  L.  S.  Jones, 
Neumade  Products  Corp.;  W.  D.  Matthews, 
Motiograph,  Inc.;  V.  J.  Nolan,  National  Car- 
bon Co.,  Inc.;  J.  F.  O'Brien,  RCA;  H.  H. 
Strong,  Strong  Electric  Corp.;  E.  J.  Vallen, 
Vallen,  Inc.;  E.  Wagner,  Wagner  Sign  Serv- 
ice, Inc.;  F.  J.  Wenzel,  Wenzel  Projector 
Co.;  C.  S.  Ashcraft,  Ashcraft  Mf°".  Co.,  and 
W.  A.  Gedris,  Ideal  Seating  Co. 

Ray  G.  Colvin  was  elected  executive  direc- 
tor of  TEDA.  The  position  of  president,  for- 
merly held  by  Colvin,  was  replaced  with 
the  new  office  to  which  he  was  elected.  Tom 
Shearer,  B.  F.  Shearer  Co.,  was  elected  chair- 
man, a  position  which  replaces  the  former 
vice-presidency. 

Elected  to  the  executive  committee  were: 
F.  A.  Van  Husan,  Western  Theatre  Supply; 
Joe  Hornstein;  W.  E.  Carrells,  Fall  City 
Equipment  Co.;  John  P.  Filbert;  Ray  Bus- 
ier, United  Theatre  Supply  Co.;  Jack  L. 
Rice;  H.  J.  Ringold,  Ringold  Theatre  Equip- 
ment Co.;  K.  R.  Douglas,  Capitol  Theatre 
Supply  Co.;  J.  Eldon  Peek,  Oklahoma  Thea- 
tre Supply  Co.;  Ernest  Forbes;  Nash  Weil, 
Wilkin  Theatre  Supply,  and  Henry  Soren- 
son,  Modern  Theatre  Equipment  Co. 


siiiM-ir-s 


SEALED 

LENS  ELEMENTS 


.  ONE-PIECE 
MOUNT 


ANODIZED 
FINISH 


,  COATED 
'  OPTICS 


Bw 


»A 


'&» 


at 


DOES  THE  F/1.9  SUPER-SNAPLITE  HAVE  A  TRUE  SPEED 
OF  F/1.9? 

Yes — in  all  sizes  from  2"  up  through  4%".  The 
5"  size  has  a  speed  of  f  2.0. 

WHY  DOES  THE  5"  SUPER-SNAPLITE  HAVE  A  DIFFERENT 
SPEED  FROM  THE  SHORTER  FOCAL  LENGTHS? 

Because  of  the  limited  space  in  the  projector.  In 
other  words,  a  5"  lens  with  a  speed  of  f/1.9 
would  not  fit  into  present  projectors  because  of 
the  large  diameter  needed  for  the  lens  barrel. 

DOES  THE  SUPER-SNAPLITE  LENS  HAVE  DIAPHRAGMS? 
No — the  full  aperture  is  utilized  in  all  focal 
lengths. 

DOES  A  FAST  LENS  ELIMINATE  THE  "HOT  SPOT"? 

To  a  very  large  extent  The  faster  the  lens,  and 
the  higher  its  quality,  the  more  uniform  the 
screen  illumination  will  be. 

IS  THE  "HOT  SPOT"  WORSE  WITH  SHORT  FOCAL  LENGTH 
LENSES? 

Usually.  The  falling  off  in  illumination  at  the 
corners  can  be  quite  severe  with  poor  lenses. 
This  problem  was  given  full  consideration  when 
Super-Snaplite  lenses  were  designed.  Even  in 
the  shorter  focal  lengths,  they  give  re- 
markably even  screen  illumination. 


"You  Get  the  Most  Uniform  Light  with  Super-Snaplite' 


kom.a\oim;1Tn    /      @ 

y^y^cai  corporation 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


23 


IP    TELECASTS 

(Continued  from  page  17) 

roster  of  talent."  It  will  also  supply 
"live"  films  tailored  specifically  to  meet 
Tv's  needs.  Par  is  also  offering  its  serv- 
ices as  film  buyer  to  interested  stations. 
#     *     * 

Battle  on  Color  Tv  Systems 
Rages  Before  the  FCC 

The  nation's  Tv  set  makers  hope  tc 
come  up  eventually  with  a  color  Tv  re- 
ceiver that  would  sell  for  only  $49.95, 
said  R.  C.  Crosgrove,  president  of  the 
Radio  Manufacturers  Association,  in  a 
recent  hearing  before  the  Federal  Com- 
munications Commission.  He  added,  how- 
ever, that  color  Tv  never  would  replace 
black-and-white,  thus  any  color  system 
that  was  approved  should  protect  set 
owners  against  having  to  buy  costly  con- 
verters or  adapters. 

"As  manufacturers,"  said  Mr.  Cos- 
grove,  "we  would  like  to  have  color  stand- 
ards set  as  soon  as  possible.  If  you  could 


do  it  tomorrow,  we  could  get  off  our  un- 
easy seats.  We  are  scared  to  death  about 
the  probable  need  for  costly  converters 
and  adapters." 

RCA  Not  Ready  on  Color  Tv 

The  FCC  has  been  asked  to  add  42 
new  Tv  channels  to  the  12  b-and-w  chan- 
nels now  available.  The  two  systems  now 
receiving  the  most  attention  are  the  elec- 
tronic system  developed  by  RCA  and  a 
mechanical  device  developed  by  Colum- 
bia Broadcasting.  RCA  asserts  that  with 
its  color  system  present  set  owners  could 
receive  the  color  images  in  b-and-w  with- 
out altering  their  receivers;  or  they 
could  receive  color  by  buying  an  inex- 
pensive converter. 

FCC  members  pounded  away  at  the 
RCA  research  director,  Elmer  W.  Eng- 
strom,  who  had  the  unpleasant  task  of 
announcing  that  RCA  was  not  quite  as 
ready  with  color  Tv  as  its  announcement 
of  last  August  had  indicated.  FCC  Chair- 
man Coy  asked  if  it  were  not  true  that 
RCA  was  willing  to  take  a  much  greater 
risk  on  b-and-w  than  on  color  Tv. 


CYCL0RAMIC 


The  FIRST 

Major  Screen 

Improvement  in 

30  Years! 


Custom  Screen 

*Patent  applied  for 


Perfect  Sound 

Transmission  •  Elimination 

Of  Backstage  Reverberation  .  Perfect  Vision  in  Front 

Rows- Setter  Side  Vision 

THE  MAGIC  SCREEN  OF 
THE  FUTURE NOW.' 


Manufactured  and 
Distributed  inclusively 
TferttghMl  tit  World  b» 


B.  F.  SHEARER  COMPANY 

LOS    ANGELES    •    PORTLAND    •    SEATTLE    •    SAN    FRANCISCO 

Executive  Offices:  2318  Second  Avenue,  Seattle  I,  Washington 


Exclusive  Export  Distributors 
FRAZAR  &  HANSEN,  LTD.,  301   Clay  St.,  San  Francisco  11,  Calif. 


CLAYTON  BALL-BEARING 

EVEN  TENSION  TAKE-UPS 

For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reek. 
Silent  Chain  Drives 

THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reels. 

CLAYTON    PRODUCTS    CO. 


31-45  Tibbett  Avenue 


New  York  63,  N.  Y. 


Coy  declared,  one  year  to  the  day  from 
his  announcement  of  the  freeze  on  Tv, 
that  the  FCC  "didn't  do  too  well  on 
b-and-w  Tv,"  and  that  it  was  unwilling 
now  to  rush  ahead  on  color.  When  Eng- 
strom  remarked  that  progress  had  been 
good  on  b-and-w,  Coy  replied,  "We've 
had  to  stop  and  revise  it,  haven't  we?" 

Commissioner  Frieda  B.  Hennock  in- 
dulged in  some  blunt  talk  with  Eng- 
strom.  "Don't  kid  us,"  she  said;  "let's 
call  a  spade  a  spade  on  this  color  thing. 
Why  don't  you  help  us?"  She  added 
that  she  and  the  FCC  are  not  willing  to 
take  the  blame  because  RCA  is  not  pre- 
pared, following  Engstrom's  admission 
that  RCA  is  months  away  from  actual 
commercial  production  of  equipment  for 
its  color  Tv  system. 

"Color  has  been  in  the  process  for  20 
years,"  said  Miss  Hennock,  "but  every 
time  we  want  something  it's  next  Spring, 
or  next  year  or  five  years  from  now.  I 
don't  believe  you  want  color." 

SMPE  66rh  Meeting  on  Coast 

More  than  300  motion  picture  engi- 
neers, including  six  from  Europe,  gath- 
ered October  10  at  the  Roosevelt  Hotel,, 
Hollywood,  for  the  66th  Semi- Annual 
Convention  of  the  Society  of  Motion  Pic- 
ture Engineers.  Technical  sessions,  ex- 
tending over  a  five-day  period,  were 
marked  by  the  presentation  of  a  record 
number  of  papers  and  demonstrations, 
with  television,  color  photography,  and 
high-speed  photography  the  major  areas 
of  the  Convention's  reviews. 

Other  discussions  were  concerned  with 
studio  lighting,  lenses,  new  film  emul- 
sions, sound  recording,  including  mag- 
netic tape;  new  film  processing  proce- 
dures, and  related  subjects. 

As  soon  as  these  papers  become  avail- 
able to  the  industry  generally  by  virtue 
of  their  publication  in  the  SMPE  Journal 
■ — which  period  may  range  upward  to  six 
months — IP  will  publish  such  meager 
data  relating  to  the  field  of  visual  and 
sound  reproduction  as  has  been  the  norm 
for  the  past  four  or  five  SMPE  meetings. 


New  Ampro  Magnetic  Tape  Recorder 

An  entirely  new  type  of  magnetic  tape 
recorder  and  playback  unit  at  a  record- 
breaking  low  price  is  announced  by 
Ampro  Corp.,  Chicago.  Based  on  an  en- 
tirely new  electronic  circuit  which  dras- 
tically reduces  size,  weight  and  cost, 
this  recorder  is  the  first  such  complete 
unit  to  sell  for  less  than  $100 — retailing 
for  $94.50. 

Weighing  only  15  pounds  and,  in 
inches,  only  8  x  8  x  11,  this  recorder 
is  truly  portable.  It  uses  standard  re- 
cording tape  and  records  on  a  "dual 
tape"  on  either  5-  or  7-inch  reels  at  3% 
inches  per  second  tape  speed.  A  full  2- 
hour  program  can  be  put  on  a  single 
7-inch  reel  of  tape. 


24 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


THE  ORIGINS  OF  THE  'MAGIC  LANTERN' 

(Continued  from  page  21) 


FIG.  4.    Bettini's  shadow  projection  with   the  lens   (1642). 


was  the  period  of  the  rise  of  optical 
science  and  practice. 

Snellius  (1580-1626)  had  worked  out 
his  well-known  law  of  refraction  by  which 
a  rational  construction  of  optical  instru- 
ments had  become  possible.  Huygens 
and,  later,  Isaac  Newton  (1642-1727), 
published  their  famous  treatises  on  the 
nature  of  light  and,  moreover,  constructed 
different  optical  apparati. 

The  study  of  microscopical  objects  and 
celestial  bodies  went  through  a  "boom" 
period,  and  so  it  can  be  easily  understood 
that  minor  scientists  like  Kircher  tried 
the  lens  as  an  improvement  for  their 
optical  devices,  asserting  priority  when 
they  had  made  an  "invention."  More- 
over, Kircher  had  read  about  experi- 
ments of  another  Jesuit,  Marius  Bettini 
(1582-1657)  which,  according  to  Kircher. 
might  be  very  useful  for  his  research. 

Bettini's  experiments  can  be  found  on 
pages  26  and  27  of  the  "Apiaria  Uni- 
versae  Philosophiae  Mathematicae" 
(1642),  which,  freely  translated,  means 
"a  miscellany  of  mathematical  philoso- 
phy." Under  the  heading  "Shadow  Pro- 
jection With  the  Lens"  (Fig.  4)  Bettini 
dealt  with  a  "secret  method  with  which, 
during  the  night,  one  can  communicate 
with  a  friend  in  another  place  with  the 
aid  of  a  hyperbolic  lens,  painted  figures, 
and  a  source  of  light."  The  figures  had 
to  be  made  of  materials  which  did  not 
affect  the  polished  surface  of  the  lens — 
wax  or  clay,  for  instance. 

First  Primitive  Condenser 

It  must  be  noted  that  the  lens  did  not 
project  an  image  of  the  figures.  These 
appeared — as  was  the  case  with  the 
figures  on  the  mirror — as  shadows.  But 
the  lens  did  achieve  a  concentration  of 
the  light,  and  we  may  consider  it  as  the 


first  primitive  condenser.  The  "hyper- 
bolic" lens  existed  only  in  the  fantasy  of 
its  inventor,  because  the  grinding  of  this 
kind  of  lens,  even  with  modern  tools,  is 
practically  an  impossibility.  So  much 
for  the  experiments  of  Bettini,  who  was 


able  to  perform  "the  art  of  mirror-writ- 
ing" at  night. 

The  first  thing  Kircher  did  was  to  ex- 
tend the  distance  between  the  mirror  and 
the  screen,  because,  as  he  wrote,  "it  was 
hardly  20  steps.  .  .  ."  He  did  this  by 
placing  a  lens  in  the  reflected  rays  which 
produced  a  sharp,  enlarged  and  inverted 
image  on  the  screen  (Fig.  3,  d,  and  Fig. 
5.  the  latter  shown  on  page  27.) 

The  plane  mirror  had  a  diameter  of 
4  cm.  and  a  lens  of  3  cm.  Fig.  5  (a  copy 
of  the  picture  in  the  "Ars  Magna"  of 
1646 )  would  seem  to  indicate  that  the 
lens  was  of  rather  a  large  focal  length. 
For  it  must  be  noted  that  the  distance 
between  the  mirror  and  the  lens  is  rather 
long,  and  that  the  enlargement  on  the 
screen  is  rather  small.  Considering  the 
technical  possibilities  of  the  17th  Cen- 
tury, this  was  the  only  means  of  avoiding 
spherical  and  chromatic  aberrations. 
Kircher  first  projected  tests  which  now 
"were  clearly  visible  at  a  distance  of 
500  feet." 

With  two  assistants  (Kasper  Schott — 
"Magia  Universalis  Naturae  et  Artis" — 
and  Georgia  de  Sepi,  who  acted  as  an 
instrument  maker)  Kircher  pursued  his 
experiments.  The  mirrors  were  made  of 
a  special  alloy  because  normal  steel 
mirrors    were    affected    by   the   ink.    Nor 


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25 


were  glass  mirrors  of  any  use,  as  the 
double  reflection  of  the  light  rays  pro- 
duced a  blurred  image. 

It  was  found  that  concave  mirrors 
worked  better  than  plane  ones,  under- 
standably, as  the  concave  mirror  reflects 
the  rays  in  a  convergent  bundle  on  the 
center  of  the  lens  and  so  produces  a 
sharper  image  than  the  plane  mirror, 
where  the  rays  reflected  in  the  margin 
of  the  lens  are  more  refracted  than  those 
which  are  transmitted  nearer  the  center 
(Fig.  3,  d).  Further,  as  mentioned  pre- 
viously, it  was  very  important  to  have  a 
well-ground  lens  which  had  to  be  spheri- 
cal or,  better  still,  "hyperbolical." 

The  First  Moving  Pictures 

The  many  performances  which  were 
given  by  Kircher  and  his  assistants  ex- 
cited a  lively  interest  and  made  a  pro- 
found impression.  Texts  were  first  pro- 
jected, then  the  dial  of  a  clock  which 
was  painted  on  the  mirror  with  a  pointer 
made  of  paper  indicating  the  correct 
time. 

Later,  geometrical  line  drawings,  filled 


in  with  transparent  paint,  were  projected, 
and  Kircher  was  surprised  at  the  fact 
that  the  colors  appeared  unchanged  on 
the  screen.  Pleased  with  this  kind  of 
projection,  he  relieved  his  feelings  in 
circumstantial  treatises. 

The  experiments  went  on.  Right  in 
front  of  the  mirror  a  cardboard  puppet 
was  placed,  the  limbs  of  which  could  be 
moved  by  invisible  threads. 

The  spectators  saw  the  first  moving 
pictures ! 

Then  a  fly  was  fixed  on  the  mirror 
with  honey,  and  a  terrifying  monster  ap- 
peared on  the  screen.  By  sticking  a 
needle  into  the  fly  and  moving  a  magnet 
behind  the  mirror  (which  in  this  case 
could  not  be  made  of  iron)  it  looked  as 
though  the  fly  moved  and  were  alive. 
This  apparatus  may  be  considered  one 
of  the  first  primitive  solar  microscopes. 

The  spectators  were  profoundly  im- 
pressed by  this  performance,  and  the 
"moving  pictures"  even  frightened  them. 
However,  Kircher  was  not  yet  satisfied. 
The  public  had  to  be  impressed  much 
more,  and  the  idea  occurred  to  him  that 
this  might  be  achieved  if  the  performance 
were  given  at  night. 

Now  he  had  to  work  with  an  artificial 
source  of  light:  a  burning  candle  was 
chosen  which  was  placed  in  front  of  a 
concave  mirror,  because  a  plane  mirror 
would  only  reflect  part  of  the  divergent 
rays  into  the  lens    (Fig.  3.  eh 

Water-Filled  Flasks  Used 

Not  always  having  the  correct  con- 
cave mirrors  at  his  disposal,  Kircher  in- 
vented another  device.  Thinking  of 
Bettini's  method  with  which  he  had  ex- 
perimented before.  Schott  wrote  about 
this  "third  art": 

"I  have  tried  it  with  Kircher  and  it 
came  out  well" — the  concave  mirror  was 
substituted  by  one  of  those  rather  large 
spherical  flasks  filled  with  water  which, 
in  the  17th  Century,  were  on  hand  in  all 
sorts  and  sizes  and  were  used  by  physi- 
cians as  "urine  receptacles." 

The  drawing  or  text  was  fixed  or 
painted  inverted  and  reversed  on  the 
water-filled  flask  at  the  side  turned  to 
the   projection  lens,   but  as  the   surface 


of  the  flask  was  spherical,  it  was  not 
possible  to  focus  all  points  of  the  figures 
on  the  screen,  and  the  image  as  a  whole 
remained  blurred  (Fig.  3,  /). 

Remarkably,  Kircher,  instead  of  using 
a  second  lens,  chose  a  flask.  We  may 
draw  the  conclusion,  therefore,  that  lenses 
still  were  rare  in  the  17th  Century.  Thus 
we  may  consider  the  device  of  Fig.  3,  e, 
as  the  first  primitive  projector  with  the 
reflector  lamp,  g,  and  the  device  of  / 
as  the  first  with  a  condenser.  1. 

As  the  light  of  a  candle  is  very  feeble 
compared  with  that  of  the  sun,  only 
figures  and  short  words  as  "pax"  and 
"salve"  could  be  shown,  but  the  influence 
of  the  darkness  on  the  spectators  was  so 
undeniable  that  the  simple  words  made 


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— quarter-century  independent  ex- 
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26 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


Iconismus   XXX/V.       J~  jo^°   $i*-- 


"ABC.DEFGHIKLMNOP  Q..R  S  T  V  X  Y  Z 
V  B  C  I)  E  h  G  H  I  K  F  Vi  V,  Q  J,  cf  If  2  J.  A  X  /    X. 

S3  T?  n  m  Jl  3  H 

o  u  ;  J  u  j  :o  '/. 
o  n  r  i  t  y  <p  x  *  ri 

O  U  T>  2.1.  X  *  X  *IJ 


FIG.  5.    Kircher's  projection  methods  as  an  improvement  of  the  old  art  of  mirror-writing  (1646). 


a  more  profound  impression  than  did  the 
moving  puppet  in  the  sunlight. 

Religious  Angle  Stressed 

Kircher  considered  this  kind  of  pro- 
jection a  very  useful  means  to  convert 
godless  people.  Therefore  he  took  great 
pains  to  project  on  the  windows  of  houses 
in  Rome,  the  window  panes  in  those 
days  being  of  paper.  We  may  imagine 
the  feelings  of  the  sinful  Roman  citizens 
when  suddenly  they  saw  the  bright  figures 
in  the  darkness  and  supposed  an  ominous 
resemblence  with  the  "Menetekel  .  .  ." 
of  King  Belshazzar. 

Schott  wrote  in  his  "Magia  Optica" 
(one  of  the  volumes  of  the  "Magia  Uni- 
versalis") that  "these  performances  of 
images  in  darkened  places  were  more 
alarming  than  those  in  the  daylight."  By 
this  art  godless  people  might  easily  be 
kept  from  committing  sin,  especially  if 
one  should  fix  a  picture  of  the  devil  on 
a  mirror  and  project  it  in  a  dark  place. 
It  is  a  pity  that  such  views  have  hampered 
the  development  of  the  projection  lantern. 


When  the  profound  seriousness  of  the 
priests  vanished,  the  "laterna  magica" 
remained  in  the  hands  of  charlatans  and 
necromancers  who  used  it  to  impress 
simple  and  superstititious  minds.  Dur- 
ing almost  two  centuries  the  lantern  had 
only  been  used  to  project  terrifying  fig- 
ures and  for  other  mysterious  purposes. 


The  development  toward  an  instrument 
for  the  use  of  scientific  instruction  and 
education  was  for  this  reason  hampered 
until  about  1850. 

Tacquet's  Lantern  Lectures 

In  the  17th  Century,  however,  then- 
was  somebody  who,  in  Kircher's  improved 
art  of  mirror-writing,  saw  not  only  an 
instrument  of  wonder  but  something 
more.  It  was  the  Belgian  Jesuit  and 
mathematician  Andreas  Tacquet  of  Lou- 
vain  (1612-1660)  who  was  the  first  to 
give  a  lantern  lecture.    He  had  met  Friar 


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INTERNATIONAL  PROJECTIONIST     •     October  1949 


27 


Martin  Martini,  a  Jesuit  missionary,  who 
had  undertaken  a  dangerous  journey  to 
China  and,  after  his  return  to  Louvain 
(1653)  visited  Tacquet  and  planned  to 
lecture  upon  his  adventures. 

Tacquet,  acquainted  with  Kircher's 
method  of  projection  (probably  by  hav- 
ing read  the  "Ars  Magna")  realized  how 
Martini's  lectures  could  gain  an  import- 
ance if  they  were  accompanied  by  pro- 
jected illustrations.  Thus  it  happened 
that  during  Martini's  narrative,  before 
the  eyes  of  the  interested  and  astonished 


MRS.  ANN  R.  KANTNER— Man- 
ager, New  Pittsburgh  Drive-In 
Theatre,  Turtle  Creek,  Pa. — says: 

"In  our  business  sound  is  im- 
portant. So  it's  RCA  100%." 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


spectators,  pictures  of  foreign  countries 
and  peoples  appeared  which  seemed  to 
come  out  of  nothing  and  also  vanished 
into  nothing. 

[To  be  Concluded] 


NEWS    PROJECTIONS 

Jottings  of  happenings  which,  while  mostly  of 

a  non-technical  nature,  have  a  bearing  upon 

general  industry  welfare  and  progress. 

ESTIMATES  say  approximately  10% 
of  next  year's  total  feature  produc- 
tion will  be  done  abroad — 35  such 
already  set — despite  the  anguished  out- 
cry of  Hollywood  technicians.  .  .  .  Para- 
mount winds  up  with  nine  of  the  50 
theatres  in  the  Malco  Circuit,  Memphis, 
divestiture  deal.  .  .  .  Total  gross  of  first- 
run  theatres  in  Los  Angeles  area  for 
1948-49  season  off  only  5  2/3%  from 
preceding-  year.  .  .  .  Paramount  retains 
only  three  of  the  15  theatres  in  the 
Dominion  Theatres,  Virginia,  splitup. 
.  .  .  Magnitude  of  theatre  concession 
sales  revealed  by  TOA  announcement 
that  $500  millions  is  annual  take  for 
popcorn,  candy,  etc. 

In-car  speakers  with  heating  attach- 
ment have  old-line  exhibs  worried  that 
drive-in  season  will  be  considerably  pro- 
longed and  cut  deeply  into  regular  thea- 
tre biz.  .  .  .  Double-barreled  blast  at 
U.  S.  equipment  manufacturers  through 
devaluation  of  various  currencies 
abroad.  U.  S.  units  set  down  on  for- 
eign shores  now  cost  43%  more;  while 
a  British  projector  landed  here,  for 
example,  bears  a  price  tag  20%  less. 
One  large  exporter  of  projection  equip- 


WORLD- 
REPUTATION 


...  the  movie-goer 

responds  to  how  he  sees  and 

hears  in  your  theatre. 

Install  CENTURY  PROJECTION 

AND  SOUND  SYSTEMS  for 

harmony  of  color  tone  and 

picture  brilliance. 


,  — .  i— 


Sold   through   recognized  theatre  supply  dealers 

CENTURY  PROJECTOR  CORP. 

NEW  YORK,  N.  Y. 


ment  informs  IP  that  concern  centers 
not  so  much  on  current  business  drop 
abroad  as  that  U.  S.  loss  will  be  "per- 
manent as  foreign  manufacturers  move 
in."  .  .  .  New  big-town,  first-run  policy 
of  feature  and  a  condensed  version  of 
musicals  not  over  five  years  old  getting 
test  in  Eastern  cities. 

Complete  separation  of  distribution 
and  exhibition  organizations  currently 
controlled  by  Fox,  Loew's  and  Warners 
within  18  months  was  asked  by  Dept.  of 
Justice  in  proposed  final  judgment  sub- 
mitted in  the  industry-wide  anti-trust 
suit.  Government  also  wants  to  have 
right  to  "police"  the  final  judgment.  .  .  . 
Clifton  Webb  rated  as  top  box-office 
draw  in  pictures  today,  due  to  his  "Mr. 
Belvedere"  series.  .  .  .  Drive-in  theatres 
expected  to  number  one  out  of  every 
eight  motion  picture  theatres  in  U.  S. 
within  two  years.  .  .  .  Cost  of  living 
generally  has  risen  31.6%  since  1945, 
reports  the  U.  S.  Bureau  of  Labor  Sta- 
tistics, while  movie  theatre  admission 
prices  have  increased  only  10^%  in 
same  period. 

Distributors  finally  forced  by  exhibi- 
tor complaints  from  all  over  the  coun- 
try to  increase  print  orders  on  releases 
by  about  30%  .  .  .  Paramount  will 
install  its  intermediate  Tv  system  in 
the  Metropolitan,  Boston.  ...  CBS  has 
recently  completed  huge  Hollywood 
studio  for  production  of  several  shows 
on  films  which  will  subsequently  play 
Tv  stations  throughout  the  country.  .  .  . 
Picture  company  profits:  Columbia  for 
year  ending  June  30  last  earned  $1,- 
07,000  net ;  Republic  for  39  weeks  ended 
July  30  earned  $730,116. 

Ignoring  obvious  dissatisfaction  of 
paying  patrons,  Fox  has  just  announced 
reissuance  of  10  old  features.  Exhibi- 
tors who  play  this  stuff  without  explicit 
notice  of  their  character  are  hurting 
this  business.  .  .  .  Paramount  is  invit- 
ing offers  for  the  stock  it  holds  in  the 
W.  S.  Butterfield  Theatres  and  the 
Butterfield  Michigan  Theatres  Co.,  in- 
volving 113  houses  in  Michigan.  Par's 
holdings  in  both  companies  approxi- 
mate 30%. 


Community  Chest  Appeal  by 
President  of  A.  F.  of  L. 

I  am  pleased  to  add  my  personal 
approval  to  the  official  endorsement 
of  the  American  Federation  of  Labor 
for  the  Community  Chest  campaigns. 
It  is  a  most  significant  and  a  highly 
important  fact  that  representatives  of 
labor,  management  and  professions 
have  been  called  upon  in  most  cities 
and  towns  to  serve  on  budget  and 
campaign  committees,  as  well  as  on 
Boards  of  Directors,  of  local  Commu- 
nity Chests  and  Red  Feather  services. 
This  is  a  most  convincing  example  of 
democracy  in  action. 

William  Green 


28 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


IN  THE  SPOTLIGHT 

(Continued  from  page  20) 

taught  basic  electronics,  while  courses  in 
practical  shop  work,  including  tele  serv- 
icing and  installation,  are  available  to  ad- 
vanced students.  These  classes  are  formed 
under  the  supervision  of  Frank  Inciardi. 
educational  director  for  Local  306. 

•  W.  B.  Clark,  former  president  of  Local 
599,  Fresno,  Calif.,  was  presented  with 
a  lifetime  membership  card.  Clarke  has 
held  every  office  in  the  Local  since  he 
became  a  member  in  1917,  and  for  ten 
years  prior  to  his  retirement  in  1947  he 
held  the  office  of  president.  The  presen- 
tation was  made  at  Clarke's  home,  where 
he  has  been  confined  to  his  bed  since  the 
early  part  of  the  year. 

•  In  an  official  NLRB  count  of  36  to  0, 
the  movie  set  decorators  voted  in  favor  of 
IATSE  representation.  This  small  group 
set  off  the  spark  that  ignited  the  long 
bitter  Hollywood  strike  about  four  years 
ago  when  Herbert  Sorrell,  business  agent 
of  the  Brotherhood  of  Painters,  Decora- 
tors and  Paperhangers  of  America, 
sought  to  gain  control  of  the  film  indus- 
try. A  majority  of  the  36  decorators  who 
voted  in  the  NLRB  election  were  former 
supporters  of  Sorrell. 

•  Seen  here  and  there  at  the  TESMA- 
TEDA  Chicago  convention :  Barney  Pearl- 
man,  former  sales  manager  for  GoldE 
Mfg.  Co.,  and  one  of  the  best  liked  men 
in  the  industry  .  .  .  George  Raaflaub, 
secretary  of  Syracuse  Local  376,  our 
sidekick  on  the  plane  flight  to  Chicago, 
crammed  up  on  a  lot  of  tele  dope.  His 
report  to  the  Local  should  be  a  very  in- 
teresting one  .  .  .  Jack  Behlke,  member  of 
Chicago    Local    110   and    field    man    for 


A 


J.  A.  CHRISTENSEN— Owner  and 
Manager,  Arcade  Theatre,  Salt  Lake 
City,  Utah — says: 

"Sound  service  is  essential  for 
patron  satisfaction.  For  many 
years  RCA  Service  has  done  an 
excellent  job  for  us." 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


Motiograph,  gained  many  new  friends 
for  his  company  by  his  courteous  and  un- 
failing willingness  to  answer  the  ques- 
tions of  the  many  visitors  to  the  Motio 
booth  .  .  .  About  650  people  attended 
the  National  Carbon  Co.  cocktail  party, 
which  was  held  in  the  Normandie  Lounge 
of  the  Stevens  Hotel.  On  hand  to  wel- 
come the  visitors  were  the  following  Na- 
tional representatives:  C.  0.  Kleinsmith, 
Dave  Joy,  W.  J.  Nolan,  Paul  Reis,  C.  E. 
Heppberger,  Erwin  Geib,  Dr.  W.  W. 
Lozier,  and,  of  course,  none  other  than 
National's  old  standby — Bill  Kunzmann, 
who  was  largely  responsible  for  the  suc- 
cess of  the  party.  A  newcomer  to  these 
affairs  was  F.  S.  Haggerson,  sales  man- 
ager of  carbon  products  for  NCC  .  .  . 
Missed  at  the  Motiograph  headquarters 
was  the  cheery  smile  and  ready  wit  of 
Mrs.  Thor  (Pat)  Matthews,  who  was 
confined  to  her  bed  with  a  cold  .  .  .  The 
IA  was  represented  by  projectionists 
from  all  parts  of  the  country — Louis 
Wutke,  Los  Angeles  Local  150;  Wallace 
Yutzy,  Minneapolis  Local  219;  Gene  Mul- 
ler,  San  Antonio  Local  407;  J.  Williams, 
Memphis  Local  144;  Fred  Parker,  Rock 
Island  Local  433 ;  a  large  delegation  from 
Milwaukee  Local  164  (mentioned  else- 
where in  these  columns)  ;  and,  of  course, 
Chicago  Local  110  members. 


IA     ELECTIONS 

LOCAL  440,  ST.  JOHN,  N.  B. 

A.  C.  Spracue,  pres.;  L.  J.  McCourt,  vice- 
pres.;  C.  Beesley,  sec.;  A.  T.  Wedge,  treas.; 
James  A.  Whitebone,  bus.  rep.;  Norman 
Peters,  L.  Spracue,  Ed  Chase,  trustees. 

LOCAL  373,  TERRE   HAUTE,   IND. 

M.  B.  Link,  pres.;  E.  F.  Kirk,  vice-pres.; 
Geo.  H.  Facg,  sec;  E.  F.  Brown,  treas.; 
B.  Steinhauser,  bus.  rep.;  C.  B.  Knott  and 
T.  A.  White,  executive  board  members. 

LOCAL  604,   CORPUS   CHRISTI,   TEX. 

Herman  Bridcers,  pres. ;  T.  W.  Rich,  vice- 
pres. ;  Leo  Beckley,  sec. -treas.;  D.  A.  Bran- 
don, bus.  rep. 


Forty-One   Years  Ago 

Middleport,  N.  Y.  Frowns  on  Movie  Shows 
An  edict  has  been  passed  by  the  city 
fathers  of  Middleport  that  moving  pic- 
ture shows  are  a  menace  to  women  and 
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men  to  establish  a  nickelodeon  here 
within  the  past  few  days  have  failed. 

Moving  Picture  World,  May  16,  1908 


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STAR  CORE,  exclusive  feature  with  the 
Lorraine  Carbons  —  a  manufacturing 
process  that  increases  the  performance 
of  the  carbons. 

A  more  brilliant,  steadier,  more  con- 
sistent white  light — more  economically 
. . .  proven  facts  as  shown  by  tests 
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Lorraine  Carbon,  are  world  rer 

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NEW  YORK:  234  WEST  44tli  STREET 


WITH  ANY     LAMP      IN  ANY  SIZE     THEATRE 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


29 


FIRE  EXTINGUISHERS  IN 
PROJECTION  ROOMS 

(Continued  from  page  12) 

monoxide  is  a  combustible,  highly  toxic 
gas;  while  the  dioxide  is  incombustible 
and  quite  non-poisonous. 

Not  only  is  carbon  dioxide  non-poison- 
ous, but  it  is  essential  to  the  existence  of 
life  on  this  planet.  The  gas  is  present  in 
the  atmosphere  to  the  extent  of  0.03% 
to  0.04% — much  more  in  large  cities. 
Without  C02  in  the  air  there  would  be 
no  plant  life.  Plants  breathe  C02  and 
exhale  oxygen.  Animals  breathe  oxygen 
and  exhale  C02.  All  the  oxygen  in  the 
earth's  atmosphere  is  the  breath  of  plants. 
There  is  probably  no  plant  life  on  Venus 
because  the  atmosphere  of  that  planet 
is  mostly  C02  with  little  or  no  oxygen; 
but  the  atmosphere  of  Mars  is  like  that 
of  the  earth  though  thinner,  hence  it 
may  be  assumed  that  there  is  vegetation 
there  to  maintain  free  oxygen  in  the 
Martian  air. 

Carbon  dioxide  is  present  in  exhaled 
human  breath  to  the  extent  of  4.4%  by 
volume.  This  gas  also  comprises  45% 
of  the  total  volume  of  dissolved  gases  in 
venous  blood,  and  38%  in  arterial  blood. 

It  can  therefore  be  understood  that 
C02  is  not  a  poison.  It  can  take  life 
only  by  excluding  oxygen  from  the 
lungs.  But  the  gas  is  not  without  physio- 
logical effect:  it  stimulates  the  respira- 
tory centers.  In  fact,  the  standard  gas- 
eous mixture  administered  to  victims  of 
gas  poisoning  consists  of  93%  oxygen 
and  7%  carbon  dioxide  to  increase  the 
rate  of  breathing. 

Very  high  concentrations  of  CO,  are 
required  to  produce  suffocation;  and 
before  death  can  occur,  the  ensuing 
stimulation  of  the  respiration  causes  dis- 
comfort and  forces  the  victim  to  seek 
fresh  air.  The  victim  is  not  "overcome" 
in  the  sense  that  he  loses  consciousness 
without  ever  having  realized  the  danger 
of  suffocation  and  the  urgent  need  for 
oxygen.  Can  you  imagine  a  projection- 
ist gasping  for  breath  while  using  a  C02 
extinguisher  and  not  having  sense  enough 
to  open  the  door  or  else  leave  the  room? 

CO.,  Use  for  Film  Fires 

The  only  danger  in  using  a  C02  ex- 
tinguisher for  putting  out  film  fires  is 
that  the  user  may  have  a  little  too  much 
confidence  in  it  and  get  burned  or 
poisoned  by  the  fumes  of  burning  film. 
I  cannot  now  advise  any  projectionist 
to  fight  a  film  fire;  but  those  intrepid 
would-be  heroes  who  insist  on  showing 
off  are  advised  to  use  nothing  but  a 
C02-type    extinguisher. 

The  jet  of  liquid  C02  from  the  tank 
freezes  to  a  solid  snow  of  "dry  ice"  which 


HARRY    HOLLAND  — Owner, 
Bishop  Theatre,  Bishop,  Calif. — says: 
"Happily,  I  endorse  the  excel- 
lent qualities  of  RCA  Service 
rendered  me  over  a  period  of 
many  years.  In  my  recently 
rebuilt  theatre  I  am  continu- 
ing with  the  dependable  RCA 
Sound  and  Service." 
To  get  the  benefits  of  RCA  Service — 
write:   RCA  SERVICE    COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


is  cold  enough  to  put  out  all  but  the 
fiercest  projection-room  film  fires.  It 
would  be  ridiculous  of  a  person  to  fear 
being  suffocated  by  the  C02  gas  evolv- 
ing from  the  dry  ice.  Rather,  he  should 
fear  bad  effects  from  the  smoke  of  the 
film  fire. 

Regardless  of  what  Eastman  Kodak 
says  about  film  burning  under  water 
(p.  14  of  IP  for  September),  most  cel- 
luloid factories  rely  on  nothing  but  water 
to  combat  fires  which  may  occur.    I  once 


set  a  full  2000-foot  reel  on  fire  outdoors 
and  put  it  out  by  simply  throwing  a 
bucket  of  water  on  it.  I  should  like  to 
try  dropping  a  blazing  reel  into  a  tub 
of  water,  but  I  have  only  a  few  reels 
of  my  own  left,  and  I  want  to  keep  them 
for  use  as  test  films.  If  someone  will 
donate  the  film,,  I'll  conduct  any  sort  of 
extinguishing  experiment  they  wish. 

Water,  to  be  effective,  must  be  ap- 
plied in  a  powerful,  continuous  stream. 
Sprinkling  systems  are  of  no  value  be- 
cause they  do  not  apply  sufficient  water 
to  cool  the  film  below  the  ignition  tem- 
perature. 

Carbon-ret  extinguishers  are  worth- 
less and  extremely  dangerous. 

Soda-acid  extinguishers  are  useless 
because  the  jet  is  too  fine  to  have  any 
cooling  effect.  Foam-type  extinguishers 
may  cause  a  disastrous  explosion  of  cel- 
luloid degradation  gases.  Both  these 
types  of  fire-fighting  devices  may  ruin 
the  projection  equipment  and  cause  elec- 
trical fires  by  short-circuiting  wiring. 

Mr.  Stewart  failed  to  identify  the 
"other  and  more  efficient"  extinguishers. 
I  have  never  heard  of  such,  but  I  am 
very  desirous  of  learning  what  they  may 
be.  Why  not  solicit  further  contribu- 
tions on  this  subject  from  Mr.  Stewart? 
I  should  like  to  think  over  any  other 
ideas  he  may  have.  Personally,  I  should 
almost  advise  against  any  type  of  ex- 
tinguisher in  projection  rooms;  but,  on 
the  other  hand,  a  small  roll  of  film  might 
ignite  which  the  projectionist  could  ex- 
tinguish with  a  C02  extinguisher. 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you  ?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

INTERNATIONAL    PROJECTIONIST. 
19  West  44  St..  New  York  18.  N.  Y. 

□  1     year — 12    issues — $2.50 
G  2   years — 24   issues — S4.00 
Foreign    and   Canada:    Add  50c   per   year. 


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30 


INTERNATIONAL  PROJECTIONIST     •     October  1949 


SO  MUCH 


for  so  LITTLE 


$0.00 


3 


per  copy 
postage   prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  far  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage   prepaid. 


Ssnd  go*  it  Vbow! 


(Do  Tbi  (Dsdaif 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street.  New  York  18,  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a  copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
Name   _ 


Address 
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FOR   SOUND   REASONS 


PROJECTION  AND  SOUND  FOR  DRIVE-IN  THEATRES 

MANUFACTURED    BY    INTERNATIONAL    PROJECTOR    CORPORATION    •    BLOOMFIELD,    NEW    JERSEY 


WiMiiiiH 


NOVEMBER 


1949 


VOLUME  24       •       NUMBER   11 


30c  A   COPY    •    S2.50  A  YEAR 


5*     N 


Imm 


WHAT  YOU  SHOULD  KNOW 
ABOUT  TB  RESEARCH 


In  universities  and  laboratories  throughout  the  country,  America's  scientists  are  con- 
ducting an  unceasing  war  against  tuberculosis.  This  year  alone,  more  than  22  separate 
yet  coordinated  studies  are  being  aided  by  the  National  Tuberculosis  Association 
and  its  affiliates  —  made  possible  by  your  purchase  of  Christmas  Seals. 

Under  investigation  are  such  questions  as  the  chemistry  and  virulence  of  the  tuber- 
culosis germ,  factors  influencing  the  course  of  early  tuberculosis,  the  reason  some  strains 
of  germs  become  resistant  to  streptomycin,  and  the  effectiveness  of  a  combination  of 
drugs  in  tuberculosis  treatment. 

Since  1904,  the  overall  TB  program  has  helped  cut  the  death  rate  by  eighty-five 
per  cent  —  yet  TB  still  kills  more  people  between  15  and  34  than  any  other  disease. 

So,  please,  buy  and  use  Christmas  Seals  —  send  in  your  contribution,  today. 


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«» 


©ClB    2l,99  7« 


INTERNATIONAL 

PRQJECTIONISI 

With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


NOVEMBER  1949 


./  Number  11 


Index   3 

High    Court    Ruling    on    Local 
Rights 5 

Multiple    16-mm    Soundtrack   in 
J.  E.  Maurer  Version 6 

The  35-mm  Projection  Positive 
Film     8 

Robert  A.  Mitchell 

Notes  on  Drive-In  Theatres ....      10 
C.  Edward  Whitford 

Theatre  Television:  What,  How 

and  When   12 

John  Evans  McCoy 
Harry  P.  Warner 

Early    Photographic     Collection 
Recalls  Governor's  Bet 15 

Film  Fire  Characteristics 16 

Richard  D.  Marks 


Letters  to  the  Editor 17 

In    the   Spotlight 18 

Harry  Sherman 

'Dancing     Shoes'     Sequence     in 
'Barkleys'    20 

Looking  Back — To  The  Future.      21 

Proposed  American  35-mm  Film 
Perforation    Standard 23 

Views  from  the  Antipodes 24 

0.  A.  Harley 

News  Projections 25 

Personnels     27 

Book  Reviews    30 

News  Notes 

Technical  Hints 

Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST  PUBLISHING  CO.,   INC. 

19  West  44  Street,  New  York  18,  N.  Y. 

R.  A.  ENTRACHT,  Publisher 
SUBSCRIPTION  REPRESENTATIVES 

AUSTRALIA:  McGills,  183  Elizabeth  St.,  Melbourne 

NEW  ZEALAND:    Te  Aro  Book  Depot,  Ltd.,  64  Courtenay  Place,  Wellington 

ENGLAND  and  DOMINIONS:  Wm.  Dawson  &  Sons,  Ltd.,  Macklin  St.,  London,  W.  C.  2 

Yearly  Subscription:  United  States  and  possessionsv$2.50  (two  years,  $4)  ;  Canada  and 
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two  weeks  in  advance  of  publication  date  toinsure  receipt  of  current  issue.  Entered  as 
second  class  matter  February  8,  1932,  ^tjfae  Post  Office  at  New  York,  N.  Y.,  under  the 
act  of  March  3,  1879.  Entire  contents^opyrighted  1949  by  International  Projectionist 
Publishing  Co.,  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 

420 
INTERNATIONAL  PROJECTIONIST     •     November  1949 


What  other 
Christmas  present 
can  you  name  that 


.you  wouldn't  want  to  exchange 


.comes  in  so  handy  on  rainy  days 


...keeps  increasing  in  value 

...is  so  quick  and  easy  to  buy 
...pleases  everyone  on  your  list 
AND... gives  itself  all  over  again 
(with  interest)  ten  years  later? 

U.  S.  SAVINGS  BONDS 

Automatic  Saving 
is  Sure  Saving 


Contributed  by  this  magazine 

in  co-operation  with  the  Magazine 

Publishers  of  America  as  a  public  service. 


9  _  ^k,  i-irw  to  Tfi  auhc 


d*** 


11 


MAGNA&C 

TRADE   MARK    M 

1-KW  TO  70  AMPS 

HY-AX"  ARC  MAGNET 


ii 


HY-LUMEN     REFLECTOR 


More  light  at  40  to  70  amperes  than  ever  thought  possible. 
.  .  .  Equals  and  excels  any  reflector  lamp  to  85  amperes,  whether 
they  be  unapproved  water-cooled  or  resurrected  "Hi-Lows".  .  .  . 
Highest  ratio  of  honest  screen  lumens  per  watt  consumed  at  the 
arc.  ...  At  70  amperes,  with  a  projector  having  an  efficient  DISC 
type  revolving  shutter,  it  develops  the  maximum  white  light  that 
can  be  used  without  a  heat  filter  at  no  risk  of  film-heat  damage. 
.  .  .  Operating  costs  under  these  conditions  are  far  below  that  of 
85-ampere  lamps. 

Magnarc  Lamps  assure  80%  side-to-center  (SMPE  Standard) 
screen  light  distribution,  not  a  deceptive  60%  or  "Hot  Center." 
.  .  .  They  are  all  Und.  Lab.,  Inc.  listed.  .  .  .  They  are  not  in- 
surance hazards.  .  .  .  They  are  and  have  been  for  years  "The 
Standard  of  Comparison"  and  "The  First  Choice"  of  large 
and  small  theatres,  drive-ins,  and  the  motion  picture  industry 
in  general! 


i  i 


FIRST    WITH    THE    FINEST 


t  i 


120-180  AMPERES 


TRADE    MARK   REG. 


NEW    MAGNETIC    STABILIZER 

This  modern  lamp  produces  all  the  light  there  is. 
...  It  is  the  standard  equipment  of  the  nation's  largest 
and  finest  theatres.  .  .  .  Used  by  90%  of  the  largest 
Drive-In  Theatres. 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  white  light  volume 
when  used  with  projectors  that  have  efficient  DISC 
type  revolving  shutters. 

Assures  satisfying  projection  for  Drive-Ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions.  .  .  .  They  are  Und.  Lab.,  Inc 
listed  and,  therefore,  not  insurance  hazards.  .  .  .  Heat 
filter  assures  no  risk  of  film-heat  damage  at  maximum 
arc  amperage. 


1  I 


WHY    EXPERIMENT? 


i  i 


t 


!•       1 


J.E.McAULEY  MFG. CD. 

552-554    WEST    ADAMS    STREET 

CHICAGO   6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST 


November  1949 


Your  Local  Union  is 
Your  Only  Security 


High-Court  Ruling  on  Local  Rights 


THIS  is  one  of  the  most  important 
stories  that  IP  has  ever  printed,  be- 
cause it  bears  directly  upon  the  personal 
security  of  every  man  who,  having  joined 
an  organization  such  as  an  IA  Local 
Union,  looks  to  that  organization — "fam- 
ily," if  you  will — to  protect  him  in  his 
livelihood.  These  are  not  only  the  impli- 
cations but  the  considered  judgment  of 
the  Supreme  Court  of  the  State  of  Cali- 
fornia in  overturning  the  decision  of  a 
lower  (Superior)  court  which  had  ruled 
that  a  Local  Union  must  continue  to  give 
employment  to  an  outside  card-member 
of  the  same  International. 

Most  important  we  think  is  the  fact 
that  the  decision  of  this  highest  State 
court  directed  that  even  had  the  Local 
Union  acted  arbitrarily  (not  sustained  by 
the  evidence),  it  .still  would  have  been 
within  its  legal  rights  in  refusing  longer 
to  honor  the  filed  working  cards  of  out- 
side members  of  the  same  International. 

The  facts  in  this  case  are  simple — but 
the  implications  are  of  tremendous  im- 
portance to  every  man  who  carries  a  card, 
whether  in  the  I A  or  any  other  labor 
union.  These  are  the  facts: 

Two  IA  members  (who  shall  be  name- 
less) journeyed  to  San  Francisco  and, 
having  deposited  their  cards  with  Local 
162,  were  given  employment.  There  was 
no  question  of  their  competency;  in  fact, 
they  worked  for  months  on'  given  jobs; 
but  they  suddenly  decided  that  by  reason 
of  the  fact  that  they  had  worked  in  the 
Local  162  jurisdiction  for  ,that  given  pe- 
riod, they  were .  entitled  to  full  member- 
ship ,in  the  Local.  -.    .       ^ 

Despite  the    fact  that  these  men  had 


By  HARRY  SHERMAN 

never  made  formal  application  to  Local 
162  for  full  membership,  they  suddenly 
withdrew  their  cards  and  addressed  a 
grievance  complaint  to  the  International 
office  in  New  York  City — this,  mind  you, 
without  a  warning  of  any  sort  (even  ver- 
bally) to  Local  162.  The  IA  General 
Office  promptly,  and  properly,  referred 
the  communication  back  to  Local  162. 

The  Inevitable  Lawsuit 

What  happened  next  is  easy  to  guess — 
a  lawsuit  to  compel  Local  162  to  admit 
these  casuals  to  full  membership  rights. 
The  basis  of  the  legal  action?  The  fact 
that  the  men  had  demonstrated  their  com- 
petency on  a  regular  projection  job  in 
Local  162's  jurisdiction. 

Into   Superior   Court  they   went;    and 


they  scored  mightily  by  coming  up  with 
a  decision  against  Local  162.  But  this  was 
not  the  last  inning,  by  far.  An  appeal  was 
taken. 

Upon  appeal,  the  California  Supreme 
Court  ruled  that  jobs,  as  such,  were  not 
vested  in  an  individual  but  in  the  organi- 
zation which,  by  joint  action  over  a  pe- 
riod of  time,  had  established  standards  of 
work  and  means  for  the  protection  of 
those  men  who  had  contributed  to  the 
building-up  and  continuing  progress  of 
their  own  organization.  Nobody  from 
hundreds  of  miles  away  was  properly  en- 
titled to  participate  in  the  benefits  of  this 
careful,  painstaking  work  over  the  years 
simply  because  he  held  a  card  in  the  same 
International. 

That  is  the  sum  and  substance  of  this 
far-reaching  decision:  local  autonomy 
prevails,  because  it   was  the   brawn   and 


IA  Constitution  and  By-Laws  [Article  17) 


Right  of  Appeal 

Section  1 :  Any  member  aggrieved 
by  the  decision  of  the  tribunal  of  this 
Alliance  may  appeal  his  case  in  the 
following  order:  (1)  from  the  decision 
of  the  Local  Union  to  the  Interna- 
tional President  of  this  Alliance;  (2) 
from  the  decision  of  the  International 
President  to-  the  General  Executive 
Board;  (3)  from  the -ruling  of  the 
General  Executive  Board  to  this  Alli- 
ance in  the  convention  assembled,  and 
the  latter  body  shall  be  the  "'tribunal  of 


ultimate  judgment.  However,  in  the 
interim,  rulings  of  any  proper  tribu- 
nal of  this  Alliance  shall  be  enforced 
pending  disposal  of  appeal. 

Exhausting  Internal  Remedies 

Section  7:  The  members  of  this 
Alliance  further  consent  to  be  disci- 
plined in  the  manner  provided  by  this 
Constitution  and  By-Laws,  and  under 
no  circumstances  to  resort  to  the  civil 
courts  until  all  the  remedies  therein 
provided  shall  have,  been  exhausted. 


INTERNATIONAL  PROJECTIONIST 


November  1949 


brains  and  guts  of  the  Local  fellows  who 
went  out  and  turned  the  trick  in  the  first 
place — the  trick  of  organizing  and  fight- 
ing and  battling  and  worrying  that  they 
would  have  a  job  to  go  to  tomorrow — not 
somebody  1000  miles  removed. 

We  want  to  say  something  very  nice 
about  the  officials  of  Local  162  who  in- 
vested their  nerve,  their  money  and  their 
courage  in  this  hard-hitting  fight,  a  fight 
that  was  won  not  alone  for  Local  162  but 
for  every  man  who  carries  an  IA  card. 

Thank  you,  from  the  bottom  of  the  well. 

So  that  every  card-holding  member  of 
the  Alliance  may  be  fully  informed  as  to 
the  importance  of  this  decision  to  his  own 
personal  welfare,  we  are  appending  ex- 
cerpts from  this  noteworthy  decision. 

Labor  Unions — Membership.  Whether  or 
not  a  labor  organization  is  arbitrarily  closed 
to  a  particular  worker  depends  on  the  facts 
of  each  case,  and  in  a  mandamus  proceeding 
by  out-of-state  members  *  *  *  to  compel  a 
local  union  to  admit  plaintiffs  to  member- 
ship, it  is  the  plaintiffs'  burden  to  prove 
that  they  are  entitled  to  membership,  that 
membership  is  closed  to  them,  and  that  it 
is  arbitrarily  closed. 

A  labor  union  is  not  compelled  to  admit 
all  persons  as  a  condition  to  maintaining 
closed-shop  agreements,  and  it  has  the  right 
to  reject  or  expel  persons  who  refuse  to 
abide  by  any  reasonable  regulation  or  lawful 
policy  adopted  by  the  union. 

Moving  picture  projectionists  who  are 
members  of  out-of-state  unions  are  not  en- 
titled* to  a  writ  of  mandate  to  compel  a 
local  union  to  admit  them  to  membership 
where  they  have  not  applied  for  membership 
and  have  not  complied  or  offered  to  comply 
with  reasonable  requirements  imposed  by 
the  union  as  conditions  for  obtaining  mem- 
bership, even  if  the  evidence  establishes  that 
any  application  for  membership  would  have 
been  arbitrarily  rejected. 

Projectionists  who  are  members  of  out-of- 
state  unions  do  not  have  an  absolute  right 
to  be  admitted  to  a  local  union  as  transfer 
members,  even  though  the  constitution  of  the 
International  union  compels  a  local  union 
to  issue  transfer  cards  to  its  members,  where 
the  constitution  of  the  International  union 
recognizes  the  right  of  the  local  union  to 
which  the  card  is  presented  to  reject  the 
applicant,  and  where  there  is  nothing  therein 
which  forbids  the  practice  adopted  by  the 
local  union  of  requiring  outside  men  to  meet 
some  or  all  of  the  qualifications  required  of 
new  members. 

It  is  not  improper  or  contrary  to  public 
policy  for  a  local  union  to  require  that  an 
out-of-state  member  file  an  application  and 
submit  to  a  re-examination  of  his  qualifica- 
tions as  a  condition  for  membership  in  the 
local  union,  and  the  mere  fact  that  he  might 
have  originally  complied  with  the  require- 
ments of  the  International  union  at  the  time 
he  joined  his  home  union,  does  not  mean 
that  he  still  meets  those  requirements,  nor 
indicate  that  he  can  and  does  meet  other 
reasonable  requirements  imposed  by  the 
local  union. 
In  a  mandamus  proceeding  by  out-of-state 


members  to  compel  membership  in  the  local 
union,  evidence  that  one  plaintiff  and  a  third 
person  presented  their  transfer  cards  to  the 
local  union,  but  were  notified  that  their 
cards  had  been  rejected  without  prejudice 
to  their  right  to  become  members  by  the  ap- 
plication method,  would  not  justify  or  re- 
quire affirmance  of  a  judgment  granting  the 
writ  of  mandate. 

Liability  for  Causing  Loss  of  Employ- 
ment— Damages.  In  an  action  by  out-of- 
state  members  against  a  local  union  for  gen- 
eral damages  for  alleged  loss  of  wages  and 
for  examplary  damages  for  alleged  conspi- 
racy to  deprive  plaintiffs  of  their  employ- 
ment as  projectionists,  the  court's  refusal  to 
grant  damages  could  not  be  successfully  at- 
tacked on  the  theory  that  plaintiffs  were 
forced  to  leave  their  work  where  the  evi- 
dence supported  a  finding  that  it  was  not 
true  that  a  conspiracy  existed,  or  that  fraud, 
malice,  intimidation  or  coercion  was  prac- 
ticed by  defendants  to  deprive  plaintiffs  of 
their  livelihood  as  motion  picture  operators 
or  of  their  membership  in  the  International 
union,  or  to  deny  them  admission  into  the 
local  union. 

Liability  for  Causing  Loss  of  Employ- 
ment. In  an  action  by  out-of-state  members 
against  a  local  union  for  general  damages 
foi  alleged  loss  of  wages  and  for  exemplary 
damages  for  alleged  conspiracy  to  deprive 
plaintiffs  of  their  employment  as  projection- 
ists,  the   court's   refusal    to    grant   damages 


could  not  be  attacked  on  the  ground  that 
plaintiffs  were  not  dispatched  to  work  as 
outside  members,  where  the  constitution  of 
the  International  union  provided  that  out- 
side men  must  keep  their  working  cards  on 
deposit  with  the  local  union,  and  plaintiffs 
admitted  that  they  had  picked  up  their  work- 
ing cards. 

Liability  for  Interference  with  Right 
to  Work.  If  out-of-state  members  of  a 
union  were  qualified  for  full  membership  in 
a  local  union,  but  the  local  union  arbitrarily 
denied  them  admission  and  at  the  same  time 
refused  to  permit  them  to  work  without  be- 
longing to  the  local  union,  the  out-of-state 
members  would  be  entitled  to  recover  dam- 
ages for  wrongful  interference  with  their 
right  to  work. 

In  an  action  by  out-of-state  members 
against  a  local  union  and  its  officers  for  gen- 
eral damages  for  alleged  loss  of  wages  and 
foi  examplary  damages  for  alleged  conspi- 
racy to  deprive  plaintiffs  of  their  employ- 
ment as  projectionists:  where  the  trial 
court's  findings  showed  that  plaintiffs'  earn- 
ings were  greatly  reduced  after  they  stopped 
working  in  the  jurisdiction  of  the  local 
union,  but  no  findings  were  made  relating 
to  plaintiffs'  right  to  damages  on  the  theory 
that  the  reduction  in  their  earnings  was 
caused  by  a  wrongful  interference  with  their 
right  to  work,  the  denial  of  damages,  at  least 
in  the  absence  of  findings  on  the  matter  was 
inconsistent  with  the  court's  conclusion  that 
plaintiffs  were  entitled  to  full  membership. 


Multiple  16-mm  Soundtrack 
in  J.  A.  Maurer  Version 

IN  an  interesting  variation  of  an  old  prin- 
ciple, J.  A.  Maurer,  Inc.  has  introduced  a 
16-mm  sound  track  in  which  the  familiar 
bilateral  type  of  recording  in  a  single  line  is 
replaced  by  a  group  of  six  smaller  variable- 
area  tracks,  each  a  duplicate  of  the  other 
and  l/6th  the  width  normally  employed.  The 
multiple  track  thus  contains  12  simultane- 
ously modulated,  identical  areas  (see  accom- 
panying illustration). 

More  uniform  reproduction  from  the  point 
of  view  of  clarity  and  naturalness  is  claimed 
for  this  method  because  much  of  the  wave- 
form distortion  that  occurs  with  the  usual 
track  is   eliminated. 

The  scanning  light  beams  of  most  16-mm 
projectors  depart  from  perfection  in  two 
ways:  (1)  they  are  not  uniformly  illuminated 
from  one  side  of  the  sound  track  to  the  other, 
and  (2)  they  are  not  correctly  adjusted  for 
"azimuth"  (that  is,  for  the  ideal  positioning 
at  an  exact  right  angle  to  the  direction  of 
film  travel). 

Numerous  studies  have  revealed  that  well- 
known  makes  of  16-mm  projectors  introduced 
from  15  to  30%   intermodulation  distortion 


The     Maurer    multiple 
16-mm  soundtrack, 

which     is    asserted    to 
give  greater  clarity 
and  naturalness  to 
reproduced  sound. 


because  of  the  lack  of  accurate  adjustment 
of  the  two  factors  mentioned.  8  to  10% 
intermodulation  distortion  is  generally  con- 
sidered the  maximum  permissible  in  the 
35-mm  industry. 

With  a  group  of  six  identical  VA  tracks  in 
place  of  one,  a  variation  even  as  great  as 
50%  in  the  illumination  in  the  projector 
sound  scanning  beam  will  still  provide  sub- 
stantially undistorted  wave  form,  the  varia- 
tion over  any  individual  modulated  area 
being  extremely  small.  Since  the  total  signal 
reaching  the  photocell  is  the  sum  of  the  sig- 
nals given  by  six  individual  tracks,  each  of 
which  has  very  low  distortion,  the  total  re- 
produced signal  has  low  distortion.  Similarly, 
the  harmonic  distortion  of  wave-form  due  to 
azimuth  error  is  reduced.  Overall  intermodu- 
lation distortion  is  brought  down  to  values  of 
the  order  of  5%. 

Early  Multiple-Track  Patents 

Although  the  multiple  track  is  new  to  the 
U.  S.  A.  for  commercial  recording  use,  the 
basic  idea  is  not  original.  As  far  back  as 
October,  1918,  a  German  patent  was  issued 
to  E.  M.  C.  Tigerstedt  for  a  sound  recording 
optical  system  that  produced  a  multiple  track. 
In  the  U.  S.  A.  patents  were  issued  to 
S.O.F.A.  Berglund  in  1926  and  1927  cover- 
ing methods  of  producing  such  tracks  and 
others  have,  at  various  times,  been  experi- 
mentally active.  .• 

The  multiple  sound  track  will  be  made 
available  as  conversion  to  all  present  owners 
ot  late-type  Maurer  recorders,  and  soon  it 
will  be  standard  equipment  on  all  new 
Maurer  recorders.  Further  details  from 
Maurer  at  37-01  31st  St.,  Long  Island  City, 
N.  Y. 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


Change  dim  screen 


Use  "NATIONAL"  High  Intensity 
Projector  Carbons  and  make 
box  office 


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' 


BOOM! 


The  term.  "National" 
is  a  registered  trade-mark  of 

NATIONAL  CARBON  COMPANY.  INC. 

Unit  of  Union  Carted* 
and  Carbon  Corporation 

GH3 

30  East  42nd  St..  New  York ,17.  N.  Y. 

Division   Sales  Offices: 

Atlanta,  Chicago.  Dallas.  Kansas  City. 

New  York.  Pittsburgh.  San  Francisco 


When  you  buy  projector  carbon; 
-BUY  "NATIONAL"! 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


The  35-mm  Projection  Positive  Film 


By  ROBERT  A.  MITCHELL 
/.    Types  of  Film 


The  first  of  a  series  of  articles  relating  to  the  anatomy,  characteristics, 
and  care  of  various  film  stocks  as  used  in  both  studios  and  theatres. 


MOTION  picture  film  differs  basic- 
ally from  ordinary  snapshot  film 
only  in  its  physical  dimensions 
and  requisite  marginal  perforations.  Each 
is  a  photographic  film  consisting  of  a 
plastic  base  coated  with  sensitized  emul- 
sion. The  light-sensitive  coatings  of  both 
cine  and  still  film  are  essentially  the 
same:  one  type  of  plastic  base  may  be 
used  for  both  kinds  of  film;  and  each  is 
exposed,  developed,  and  "printed  out" 
on  other  sensitized  photographic  materi- 
als by  processes  which,  as  far  as  funda- 
mental principles  go,  are  analogous  with 
each  other. 

The  picture  which  is  brought  out  by 
developing  a  correctly  exposed  camera 
film  (cine  or  still)  has  a  characteristic- 
ally unnatural  appearance.  All  values  of 
light  and  shade  are  reversed:  the  dark 
objects  in  the  original  scene  come  out 
light  on  the  film,  and  the  highlights  come 
out  dark.  The  tonal  values  of  the  camera- 
film  picture  are  therefore  negative  in 
relation  to  the  tonal  values  of  the  origi- 
nal scene. 

Negative  pictures  are  obviously  ill- 
suited  for  exhibition  purposes,  either  in 
snapshot  albums  or  on  motion  picture 
screens.  So,  in  order  to  get  faithful  rep- 
resentations of  the  original  scene  (images 
in  which  the  highlights  and  shadows  cor- 
respond with  those  of  the  photographed 
scene)  the  negatives  are  printed  on  other 
pheto-sensitized  materials  which  are  sub- 
sequently developed  in  about  the  same 
way  that  the  original  negatives  were  de- 
veloped. 

The  'Reversal'  Process 

With  the  preparation  of  the  print,  two 
"reversals"  have  taken  place.  The  tonal 
values  of  the  printed-out  picture  are  nega- 
tive to  those  of  the  camera-film  picture, 
but  positive  to  those  of  the  original  scene. 
The  "positive"  made  by  printing  the 
"negative"  accordingly  provides  a  reason- 
able facsimile  of  the  scene  viewed  by  the 
camera's  eye. 

A  snapshot  negative  is  ordinarily 
printed  on  paper  coated  with  photogra- 
phic emulsion ;  but  a  motion  picture 
negative  must  be  printed  on  emulsion- 
coated   perforated   film. 

There  is  no  great  difference  between 
negative  and  positive  "raw  stock,"  the 
term  applied  to  undeveloped  motion  pic- 
ture film.  In  fact,  it  would  be  possible 
to  photograph  a  motion  picture  on  posi- 
tive stock  and  print  it  on  negative  stock, 
but  the  quality  of  the  picture  might  be 


very  poor  in  such  a  case.  There  are  many 
different  grades  of  emulsion  available, 
with  each  having  been  produced  to  give 
the  best  results  when  used  in  the  applica- 
tion for  which  it  is  specifically  intended. 

Types  of  35-mm  Cine  Film 

Because  several  types  of  plastics  are 
used  for  the  emulsion-supporting  base  of 
film,  we  sometimes  find  it  convenient  to 
classify  motion  picture  film  according  to 
the  nature  of  the  base.  The  two  principal 
categories  of  cine-film  base  are  "inflam- 
mable" and  "safety."  A  number  of  speci- 
fic types  are  found  in  each  of  these  two 
classes: 

(A)  Inflammable  (Nitrate)  Base: 
Cellulose  pentanitrate  (nitrogen  con- 
tent 12.8%)  ;  Cellulose  tetranitrate 
(nitrogen  content  11.1%)  ;  Cellulose 
trinitrate  (nitrogen  content  9.1%). 
[Ordinary  nitrate  film  base  is  a  mix- 
ture of  these  three  nitrates,  the  tetra- 
nitrate  predominating.] 

(B)  Safety  Acetate  Base: 
Cellulose  diacetate, 
Cellulose    acetopropionate, 
Cellulose  triacetate, 
Butyril   acetate, 

.  .  .  and  others. 

This  system  of  classification  is  ex- 
tremely useful  to  all  who  process,  repair, 
project,  or  store  motion  picture  films. 
Solubility  in  cementing  fluids,  flamma- 
bility,  tensile  strength,  flexibility,  resist- 
ance to  the  action  of  heat,  permanence, 
etc.,  are  among  those  properties  of  film 
which  are  either  wholly  or  largely  deter- 
mined by  the  base.1 

But  those  who  are  concerned  only  with 
the  photographic  aspects  of  motion  pic- 
tures consider  film  from  an  entirely  dif- 
ferent point  of  view.  The  cameraman,  for 
instance,  is  concerned  primarily  with  the 
light-recording  characteristics  of  the 
emulsion,  and  he  can  afford  to  ignore 
completely  many  of  the  properties  of  film 
which  are  of  vital  interest  to  the  projec- 
tionist. The  processing  technician,  how- 
ever, makes  use  of  both  points  of  view, 
the  physical  and  the  photographic.  The 
film  laboratory  may  therefore  be  re- 
garded as  a  bridge  directly  connecting 
the  complementary  fields  of  cinematog- 
raphy and   projection. 

Film  is  classified  photographically  as 
"positive"  and  "negative,"  a  distinction 
based  not  on  any  fundamental  differences 
between  the  two  kinds  but  rather  on  the 


applications  for  which  they  are  manufac- 
tured. In  general,  a  film  made  for  use 
in  cameras  is  negative  stock,  while  that 
intended  for  use  in  printers  (and,  later, 
projectors)  is  positive  stock.  But  positive 
stock  is  used  as  a  negative  in  soundtrack 
recorders  and  in  title  cameras,  and  nega- 
tive stock  is  used  as  a  positive  after  it 
has  been  developed  by  a  special  reversal 
process. 

Now,  both  positive  and  negative  stock 
include  many  different  grades  and  types 
of  emulsion,  permitting  further  classi- 
fication : 

(A)  35-mm  Positive  Stock: 
Regular  positive, 

Sound  positive, 
Duplitized    positive, 
.  .  .  and  others. 

(B)  35-mm  Negative  Stock: 
Orthochromatic  negative, 
Panchromatic   negative, 
Extrasensitive  panchromatic  nega- 
tive, 

Background  negative, 
Infra-red  negative, 
Reversal  negative, 
Duplitized  color  negative, 
Monopack  color  negative, 
.  .  .  and  others. 

Positive  Raw  Film  Stock 

On  the  whole,  positive  emulsions  are 
"slower"  (less  sensitive  to  light)  than 
negative  emulsions.  Regular  Positive,  for 
example,  is  only  about  1/10  as  "fast"  as 
Panchromatic  Negative.  This  means  that 
ordinary  positive  stock  requires  approxi- 
mately 10  times  the  exposure  needed  by 
Panchromatic  Negative  to  produce  the 
same  density  of  image. 

The  wide  latitude  (high  contrast-fac- 
tor) of  positive  stock  compensates  for 
the  comparatively  low  range  of  contrasts 
in  negative  picture  images.  This  char- 
acteristic also  makes  positive  raw  stock 
useful  as  a  "negative"  for  photographing 
movie  titles  in  which  the  very  highest 
degree  of  contrast  between  the  white 
lettering  and  the  black  background  is 
desired. 

The  color  response  of  positive  stock 
does  not  match  the  color  sensitivity  of 
human  vision.  Red,  orange,  and  yellow 
look  very  bright  to  the  eye,  but  positive 
emulsion  is  so  little  affected  by  these 
colors  that  when  film  of  this  type  is  used 

1  Parts  V  and  VI  of  this  series  are  devoted  to 
film-bise  characteristics  and  their  significance 
in    projection    practice. 


3 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


in  a  camera,  red  and  orange  objects 
photograph  as  if  they  were  black.  Posi- 
tive emulsion  is  only  slightly  sensitive  to 
yellow  and  green,  but  is  very  sensitive 
to  blue,  violet,  and  the  invisible  color 
called  ultra-violet. 

The  structure  of  positive  emulsion  is 
extremely  fine-grained,  even  with  ordi- 
nary developing.  This  noteworthy  feature 
permits  tremendous  magnifications  of 
the  tiny  film-pictures  without  appreciable 
loss  of  picture  detail — an  important  con- 
sideration in  the  projection  of  motion 
pictures  on  large  screens. 

The  unexcelled  fineness  of  grain  and 
emulsion  stability  are  qualities  which 
make  positive  stock  the  ideal  negative  for 
sound  recording.  The  special  type  known 
as  Sound  Positive,  prepared  specifically 
for  this  work,  is  from  2  to  3  times  faster 
than  Regular  Positive,  and  is  footage- 
numbered  along  the  edges  to  help  the 
film-cutter  match  sound  and  picture  when 
assembling  negatives  in  the  studio. 

Tinted  Projection  Prints 

In  the  days  of  silent  motion  pictures 
from  80%  to  90%  of  the  total  output  of 
projection  prints  was  made  on  tinted-base 
positive  stock.  Each  mood  and  locale  in 
a  photoplay  suggested  an  appropriate 
hue,  and  the  stockroom  of  the  old-time 
film  laboratory  accordingly  never  lacked 
an  assortment  of  tints  sufficiently  inclu- 
sive to  meet  any  possible  exigency  of 
dramatic  atmosphere  and  "artistic" 
whim.  One  film  manufacturer  regularly 
supplied  sixteen  colors2  of  tinted-base 
positive  in  addition  to  the  regular  clear- 
base  stock  and  a  special  neutral  gray 
film  for  low-key  effects! 

With  the  advent  of  sound,  the  rainbow 
hues  which  softened  and  glamourized 
the  screens  of  yesteryear  departed  from 
the  cinema  with  their  gentle  sisters,  the 
dialogue  "subtitle"  and  the  sympathos  of 
the  theatre  organ.  So  thoroughly  aban- 
doned was  the  use  of  tinted  stock  by 
producers  unwilling  to  risk  the  quality 
of  their  soundtracks3  that  today  only 
clear-base  positive  is  regularly  manu- 
factured. 

Duplitized  Positive  is  a  double-coated 
film  used  for  making  two-color  "natural" 
color  prints.  By  means  of  special  print- 
ing and  processing  procedures,  one  side 
of  the  film  is  printed  with  the  red  (or 
red-orange)  component  of  the  picture, 
and  the  other  side  with  the  comple- 
mentary blue-green  (or  blue)  component. 
The  superposition  of  the  two  colored 
component  images  in  exact  registration 
results  in  an  approximation,  or  sugges- 


2  Red,  three  hues  of  pink,  three  of  amber,  yel- 
low, two  hues  of  green,  three  of  blue,  and  three 
of  violet. 

3  Experts  have  questioned  whether  tinted  stock 
causes  variations  in  sound  volume  too  great  to 
be  tolerated.  In  any  event,  the  subject  of  tinted 
film  is  too  intriguing  to  be  dismissed  with  these 
brief  remarks.  Additional  data  must,  however, 
be  deferred   to  the  last  part  of  this   series. 


FIGURE    1 

Th  ree  types  of 
film  stocks,  show- 
ing the  transition 
from  negative  to 
positive,  with 
sound  track  en- 
larged. 


PICTURE 
NEGATIVE 


tion,  of  natural  color.  (Three  colors  are 
required  for  true  natural  color.) 

Color  prints  of  the  Monopack  type  are 
true  full-color  reproductions.  The  emul- 
sion of  a  Monopack  color  film  (there  are 
several  brand  names)  consists  of  three 
separate  emulsions  on  the  same  side  of 
the  film.  When  processed,  these  emul- 
sions provide  a  combination  of  the  yellow, 
magenta  and  cyan  components  of  the 
original  colored  scene. 

Technicolor  prints  accomplish  the 
same  end  (in  a  more  faithful  manner) 
by  imbibition  printing  with  yellow,  ma- 
genta, and  cyan  dyes. 

Negative  Raw  Film  Stock 

Negative  stock  is  available  in  a  wide 
variety  of  emulsions.  The  slowest  type, 
Orthochromatic  Negative,  is  but  a  trifle 
faster  than  Sound  Positive,  and  only 
about  i/4  as  fast  as  the  regular  Panchro- 
matic Negative.  In  the  matter  of  color 
response,  Orthochromatic  Negative  rep- 
resents only  a  slight  improvement  over 
Regular  Positive.  It  is  somewhat  sensitive 
to  yellow,  but  quite  insensitive  to  red. 
This  type  of  negative  film  is  usually  pro- 
vided with  an  anti-halation  backing  of 
red  gelatine  to  eliminate  "flare  spots" 
from  excessively  bright  objects  in  photo- 
graphed   scenes. 

Panchromatic  Negative  is  the  most 
commonly  used  type  of  35-mm  negative 
stock.  It  is  rather  fast  (about  4  times 
faster  than  Orthochromatic  Negative  and 
10  times  faster  than  Regular  Positive) 
and  moderately  fine-grained.  By  using 
special  developers,  extremely  fine-grained 
images  may  be  obtained  with  Panchro- 
matic   Negative. 

All  panchromatic  emulsions  possess 
color  characteristics  similar  to  those  of 
the  human  eye.  They  are,  therefore,  most 
sensitive  to  red,  orange,  and  yellow.  They 
are  less  sensitive  to  green  than  to  other 
colors,  and  are  usually  coated  on  the 
reverse  side  with  green  gelatine  to  reduce 
halation. 


SOUND 
NEGATIVE 


PROJECTION 
POSITIVE 


The  panchromatic  emulsions  do  not 
have  the  great  contrast  range  of  positive 
emulsion,  but  they  faithfully  record  fine 
detail  in   both   highlights   and   shadows. 

Special-Purpose  Film  Bases 

Extra-sensitive  Panchromatic  Negative, 
3  or  more  times  faster  than  ordinary 
Panchromatic  Negative,  is  an  ideal  stock 
for  use  under  adverse  lighting  conditions. 
Newsreel  cameramen  accordingly  find 
this  type  of  sensitized  material  an  indis- 
pensable aid  to  photography  at  night,  in 
stormy  weather,  inside  dimly  illuminated 
halls,  etc.  Nevertheless,  the  use  of  Extra 
sensitive  Panchromatic  Negative  is 
avoided  as  much  as  possible  in  ordinary 
work  because  of  its  very  limited  contrast 
latitude    and   coarse   grain. 

Background  Negative  is  an  extremely 
fine-grained,  but  comparatviely  slow, 
panchromatic  film  made  for  the  photog- 
raphy of  "background  scenery"  which  is 
to  be  projected  on  transparent  screens 
in  front  of  which  actors  perform  on 
studio  sets.  The  excellence  of  modern 
"process  projection"  is  due  in  part  to 
Background   Negative. 

Infra-red  Negative  is  a  film  sensitive 
to  invisible  infra-red  light — the  color  of 
longer  wave-length  than  the  deepest  red 
that  the  human  eye  can  perceive.  When 
used  in  conjunction  with  the  proper 
filters,  Infra-red  Negative  makes  possible 
moonlight  effects  of  breath-taking  beauty 
' — brilliant  foliage  contrasts,  fleecy-white 
clouds  in  velvet-black  skies,  etc.  All  infra- 
red emulsions  are  rather  unstable  and 
require  careful  handling  and  processing. 

Reversal,  Duplitized  Negatives 

Reversal  Negative  (sometimes  called 
Direct  Positive)  is  a  panchromatic  nega- 
tive especially  adapted  to  reversing  by 
a  special  developing  process.  By  "revers- 
ing" is  meant  a  reversal  of  the  values  of 
light  and  shade  so  that  the  film  exposed 
(Continued  on  page  29) 


INTERNATIONAL  PROJECTIONIST 


November  1949 


THE  North  Drive-in  Theatre  on  Route 
11  between  North  Syracuse  and  Ci- 
cero, N.  Y.,  is  a  noteworthy  example  of 
the  modern  drive-in  equipped  to  meet 
the  highest  standards  in  visual  and  sound 
projection.  Opened  June  18  last,  it  is 
owned  and  operated  by  McConnel-Read 
Corp  of  Syracuse,  N.  Y.,  and  was  de- 
signed by  Leon  Einhorn,  architect,  Al- 
bany, N.  Y.  In  area  and  design,  it  is 
potentially  a  1000-car  theatre;  currently, 
700  speakers  are  in  use. 

In  designing  and  equipping  this  thea- 
tre, every  care  was  exercised  to  insure 
patrons  an  opportunity  to  see  and  hear 
the  performance  with  the  utmost  satis- 
faction. This  is  no  mean  accomplish- 
ment in  the  sphere  of  the  drive-in  theatre, 
which,  because  of  its  physical  nature,  not 
only  falls  heir  to  the  projection  problems 
of  the  largest  conventional  theatres,  but 
tends  to  aggravate  these  difficulties  as 
well  as  having  to  contend  with  some  pe- 
culiar to  itself.  In  the  main,  these  diffi- 
culties relate  to  the  great  size  of  the 
screens,  the  long  "throws,"  atmospheric 
liability,  and  extension  of  audience  dis- 
persal. 

Projection  Facilities,  Housing 

Projection  facilities  at  the  North  are 
such  as  to  effeptively  cope  with  these 
difficulties,  and  make  possible  a  steady, 
undistorted  54-foot  image  of  such  brilli- 
ance and  definition  as  to  be  visible  in 
detail  from  a  distance  of  half  a  mile. 

The  projection  department  occupies 
two  rooms  in  the  main  building  in  the 
center  of  the  fifth  ramp,  280  feet  from 
the  screen.  Running  the  width  of  the 
building,  the  combined  length  of  the 
rooms  is  37  feet.  The  projection  room 
proper,  in  feet,  is  20  long,  11  wide  and 
8  high.  Its  equipment  includes:  two  film 
projectors,  amplifier  racks,  rewind  bench, 
film  cabinet,  record  player  and  micro- 
phone. 

The  generator  room  is  17  x  11  x  8  feet 
and  houses  a  360-ampere  Century  Acto- 
decter  with  a  40  h.p.  motor,  the  arc 
rheostats,  and  a  rotary  positive  air  com- 
pressor, powered  by  a  Wagner  iy2  h.p. 
motor. 

The  projector  components  are:  Bren- 
kert  BX-80  mechanisms  with  Kollmorgen 
F:1.9  Super  Snaplite  lens,  Brenkert  Su- 
pertensity    arc    lamps,    model    A-4,    and 


Notes  on  Drive-In  Theatres 

By  C.  EDWARD  WHITFORD 
Member,  IA  Local  376,  Syracuse,  N.  Y. 


Brenkert  heavy-duty  bases.  The  sound 
heads  are  RCA  PG-285's;  changeover 
devices  are  Essannay  Zippers. 

Air  jets  are  used  to  cool  the  film  at  the 
aperture.  The  air  is  drawn  through  a 
filter  outside  the  building,  compressed, 
and  piped  under  two  pounds  pressure  to 
a  pair  of  nozzles  front  and  rear  of  the 
apertures.  This  method  of  cooling  has 
proved  successful  at  the  North,  with  the 
heat-laden  air  being  rapidly  removed 
before  its  heat  is  absorbed  by  machine 
parts. 

This  heat  removal  is  aided  by  the  ex- 
haust fan,  integral  with  the  BX-80  pro- 
jector, and  by  the  arc  lamp  exhaust  sys- 
tem. The  latter  function  is  made  possi- 
ble by:  (1)  the  absence  of  any  glass  heat 
filter  between  lamp  and  film;  (2)  the 
double-walled  structure  of  the  lamphouse 
which  creates  a  suction  through  the  cone ; 
(3)  the  fact  that  the  lamp  may  be  ex- 
hausted at  a  very  high  rate  without  arc 
turbulation,  and  (4)  the  powerful  fan 
exhausting  the  lamps. 

The  lamps  are  so  recent  in  design  and 
production  that,  at  this  writing,  only 
eight  are  in  service  nationally.  At  the 
North,  a  13.6-mm  National  Super  H.  I. 
rotating  positive  is  used  with  a  %-inch, 
heavy-duty  Orotip  negative.  Line  voltage 
is  105,  and  the  arc  draws  170  amperes. 

Arc  Lamp,  Projector,  Sound 

Within  the  lamp,  current  is  conducted 
ta  the  arc  in  such  a  way  that  no  arc 
stabling  magnet  is  necessary.  Correct 
arc  burning  is  facilitated  by  adjustment 
mechanism  which  provides  for  vertical 
tilting  of  the  negative  as  well  as  for  hori- 
zontal positioning.  The  two-element  con- 
denser combination  has  a  speed  of  F:2.0, 
with  each  element  being  individually 
mounted  and  both  cooled  by  air  from  a 
blower  mounted  at  the  rear  of  the  lamp 
with  the  carbon  feed  mechanism. 

The  design  of  the  BX-80  mechanism 
includes  a  feature  which  solves  a  serious 
problem  peculiar  to  drive-in  operation — 
the  presence  of  airborne  dust,  fumes,  and 


The  non-operating,  or  gear,  side  of  the  pro- 
jector, and  the  path  of  the  compressed  airline 
from  the  front  wall  to  the  projector.  Another 
air  nozzle  is  hooked-up  to  the  film  side  of 
the  mechanism. 

From  the  wall  the  airline  is  reduced  to 
'4-inch  copper  tubing.  The  hump  shown  in  the 
tube,  as  it  curves  upward  and  down  to  the 
projector,  serves  two  purposes:  (1)  it  provides 
flexibility  of  the  tubing  to  absorb  vibration  and 
to  permit  any  possible  change  in  projector 
tilt,  and  (2)  permits  the  projectionist  to  have 
unobstructed  access  to  side  of  projector  at  the 
front. 

moisture.  This  hazard  is  minimized  by 
the  mechanism's  oiling  system  which 
employs  a  circulating  oil  bath  in  a  sealed 
gear  compartment. 

The  sound  system  is  an  RCA  PG-285 
having  two  main  amplifiers  of  250  watts 
audio  output  each.  In  regular  service, 
each  amplifier  serves  350  of  the  700  in- 
car  speakers.  In  emergency,  either  one 
can  assume  the  full  load,  indefinitely. 
In  the  projection  room,  two  in-car  speak- 
ers, each  monitoring  its  own  amplifier, 
provide  a  constant  check  on  individual 
amplifier  performance. 

Last,  but  by  no  means  least,  in  con- 
tributing to  patron  satisfaction  is  the 
forward  tilt  of  the  screen.  This  serves  to 
minimize  keystone  distortion,  and  to  re- 
flect the  picture  at  the  audience,  which, 
after  all,  does  pay  to  see  it. 


-.-'i«*J 


THE  VITAL  ELEMENTS  THAT  MAKE  POSSIBLE  A  DRIVE-IN   THEATRE:  SCREEN,  PROJECTION    ROOM,  AND   PROJECTOR 
Massive   screen    mounting  Projection    room    housing  Projection  room  installation 


V  \ 


rjmE'S  EVEN 
J0RE  LIGHT 

THAN 

nU'U  NEED' 


STRONG  MIGHTY  90 

O  ■  ,%    «  to  130  Ampere 


// 


Ampere 


*  PROJECTS  21,000  LUMENS  [at  90  amperesl-26,000  LUMENS 
[at  130  amperes]  as  compared  to  17,000  lumens  for  the  70  ampere  Suprex 
or  7,000  lumens  for  the  1  K.W. 
•  THERE'S  NO  SCREEN  TOO  BIG  FOR  THE  STRONG   MIGHTY  "90"! 
IMPRESSIVELY   MASSIVE   LAMPHOUSE       •  UNIT  CONSTRUCTION 

Various  components  instantly  removable  for  cleaning  and  in- 
spection. 


combines  with 

•  FORCED  AIR  COOLING 
ofthecarbon  feed  mechanism  to  insure  lowoperatingtemperatures 

•  RUGGED  BURNER  MECHANISM 


*  EXCLUSIVE  LIGHTRONIC 
AUTOMATIC  CONTROL  SYSTEM 

Maintains  the  position  of  the  positive  arc  crater  at  the  exact  focal 
point  of  the  reflector.  The  positive  and  negative  carbons  are 
advanced  so  as  to  maintain  proper  arc  gap  length  by  separate 
motors,  the  speeds  of  which  are  governed  by  the  Bi-Metal  Light- 
ronic  Tube.  Once  the  arc  is  struck  no  manual  adjustment  or 
further  attention  is  required. 

*  BIG  16-1/2  INCH  REFLECTOR 

matches  high  speed  fl  .9  lens. 

*  COMPLETE  COMBUSTION  OF  BLACK  SOOT 

is  assured  by  a  stream  of  air  directed  just  above  the  arc  and 
which  stabilizes  its  burning  and  carries  away  the  white  smoke 
which  would  otherwise  be  deposited  on  the  reflector. 


•  MANY  ADVANTAGES  AVAILABLE  IN  NO  OTHER  LAMP 

•  BACKED  BY  THE  FAMOUS  STRONG  GUARANTEE 

Build  your  business  with  more  brilliant  pictures.  See  an  actual 
demonstration  in  your  own  theatre  or  drive-in  now  and  you'll 
be  convinced  that  here  is 

THE  FINAL  WORD  IN  HIGH  POWERED  PROJECTION  ARCS! 

Use  coupon  now  to  arrange  free  demonstration.  No  obligation. 


THE  STRONG  ELECTRIC  CORPORATION 

31  City  Park  Avenue  Toledo  2,  Ohio 

□    I  would  like  a  demonstration  of  the  Strong  Mighty  "90"  in  my 
theatre,  without  cost  or  obligation. 

Please  send  free  literature  on  the  □  Mighty  "90";  □  Mogul 
Lamp;  □  Utility  Lamp;  □  Strong  Arc  Spotlamps;  Q  Strong 
Rectifiers;   □  Strong  Reflectors. 

Name 

Theatre 

Street 

City  &  State 


INTERNATIONAL  PROJECTIONIST 


November  1949 


11 


THERE  are  strong  signs  that  the  mo- 
tion picture  industry,  in  facing  the 
problems  created  by  the  spectacular 
boom  in  home  television  (Tv)  and  its 
impact  on  motion  picture  theatre  attend- 
ance, intends  to  "fight  Tv  with  Tv."  The 
creation  of  what  amounts  to  a  new  me- 
dium of  mass  entertainment  and  com- 
munication involves  numerous  technical, 
economic,  and  legal  problems,  and  calls 
for  broad  vision,  clarity  of  thinking,  and 
inspired  leadership. 

Theatre  Tv  involves  the  exhibition  of 
visual  and  aural  television  programs  on 
large  screens  (about  15  x  20  feet). 
These  programs  are  photographed  out- 
side the  theatre  by  regular  Tv  cameras, 
transmitted  to  the  exhibiting  theatre  over 
microwave  radio  relays,  coaxial  cables, 
or  telephone  wires,  and  received  in  the 
exhibiting  theatre.1 

In  the  United  States,  two  systems  of 
theatre  Tv  equipment  have  been  devel- 
oped for  the  purpose  of  projecting  the 
program  to  the  screen:  the  direct-pro- 
jection and  the  intermediate-film  systems. 

Tv  broadcast  stations  licensed  by  the 
FCC  are  intended  to  transmit  programs 
to  the  public  generally,  primarily  for  re- 
ception in  the  home.  Theatre  Tv  does  not 
come  within  this  definition  because  its 
programs  are  beamed  directly  by  means 
of  closed-circuit  coaxial  cables  or  wires, 
or  by  directional  microwave  relays,  to 
the  exhibiting  theatre,  and  they  are  not 
intended  to  be  received  by  the  general 
public. 

Theatre  Tv  Development 

Large-screen  projection  Tv  is  nearly 
as  old  as  the  direct-view  Tv  that  pre- 
dominates in  home  reception.  In  1930, 
Tv  on  a  6  x  8-foot  screen  was  shown  by 
RCA  at  RKO-Proctor's  58th  Street  Thea- 
tre, New  York.  Large-screen  theatre  Tv 
on  a  15  x  18-foot  screen  was  exhibited 
in  London,  England,  in  1939,  and  by  the 
end  of  that  year  five  theatres  were  so 
equipped.  In  1941,  a  Madison  Square 
Garden  prize  fight  and  a  Brooklyn 
Dodgers  baseball  game  were  demon- 
strated to  the  public  by  RCA  on  a  15  x 
20-foot  screen  in  the  New  Yorker  Thea- 
tre. The  onset  of  war  interrupted  the 
further  development  of  theatre  Tv  in 
*both  England  and  the  United- States. 

During  the   general  frequency  alloca- 


(1)  Other  uses  of  Tv  by  the  motion  pic- 
ture industry  might  include  (1)  ownership 
of  Tv  broadcast  stations,  and  (2)  develop- 
ment of  pay-as-you-see  plans  such  as  Zenith 
Radio   Corp.'s  "Phonevision." 


FIRST  OF  A  SERIES  OF  ARTICLES  WHICH  BY  REASON  OF  THEIR 
INCLUSIVENESS  CONSTITUTE  A  'MUST'  FOR  A  THOROUGH  UNDER- 
STANDING OF  THEATRE  Tv  IN  TERMS  OF  EQUIPMENT  USED, 
RADIO-FREQUENCY  REQUIREMENTS,  METHODS  OF  PROGRAM  DIS- 
TRIBUTION, CAPITAL  COSTS  OF  A  NATION-WIDE  SYSTEM,  AND 
SOME  ASPECTS  OF  PROGRAMMING  IN  MOTION  PICTURE  THEATRES. 


Theatre    Television: 
What,  How  and  When* 


By  JOHN  EVANS  McCOYt 


and  HARRY  P.  WARNERt 


tion  hearings  held  before  the  FCC  in 
1944  and  1945,  Paul  J.  Larsen,  on  be- 
half of  the  Society  of  Motion  Picture 
Engineers,  appeared  and  requested  the 
allocation  of  frequencies  to  theatre  Tv. 

After  the  war,  Paramount  Pictures  di- 
rected its  research  to  the  development 
of  the  intermediate-film  method  of  thea- 


date  similar  exhibitions  have  been  given 
frequently. 

Meanwhile,  RCA,  collaborating  with 
20th  Century-Fox  and  Warner  Brothers, 
proceeded  with  the  development  of  the 
direct-projection  system  of  theatre  Tv. 
In  July,  1947,  20th  Century-Fox  and 
Warner  Brothers  signed  joint  research 
agreements  with  RCA  for  common  par- 


tre   Tv  which  culminated   on   April   14,      ticipation    in    the    development    of    this 
1948,  in  the  surprise  public  exhibition  of      system. 


a  15-minute  televised  newsreel  at  the 
Paramount  Theatre,  New  York.  The 
images  were  transmitted  via  a  7000- 
megacycle  microwave  relay  from  the 
Navy  YMCA,  Brooklyn,  to  the  top  of 
the  Daily  News  Building  on  East  42 
Street,  thence  to  the  Paramount  Build- 


The  three  organizations  sponsored  a 
private  showing  of  theatre  Tv  (15  x  20- 
foot)  at  Warner's  Burbank  Studio  in 
May,  1948;  and  on  June  25,  1948,  his- 
tory was  made  by  the  public  showing  in 
the  Fox-Philadelphia  Theatre  of  instan- 
taneous Tv  pictures  of  the  Louis-Walcott 


ing    at    Broadway    and    43    Street,    and      prize  fight,  using  an  intercity  relay  from 


from  there  down  a  coaxial  cable  to  the 
receiving  and  film-making  equipment. 

RCA-F ox-Warner  Theatre  Tv 

The  pictures  were  filmed  on  regular 
35-mm  stock,  and,  because  of  the  new 
rapid  film-developing  process,  reached 
the  18  x  24-foot  screen  66  seconds  after 
the  scenes  were  shot.  On  June  25,  1948, 
the  same  process  was  employed  at  the 
Paramount  Theatre  in  a  showing  of  the 
Louis-Walcott  prize  fight,  and  since  that 


*  Reprinted  from  Vol.  IV,  No.  2,  of  The  Hollywood  Quarterly  with  its  kind  permission. 
fNoTE:    The  opinions  and  conclusions  stated  are  the  personal  views  of  the  authors. 

John  Evans  McCoy  is  Chief,  Television  Branch,  Law  Bureau,  Federal  Communica- 
tions Commission;  Harry  P.  Warner  is  author  of  "Radio  and  Television  Law,"  con- 
tributor to  law  journals  and  other  periodicals  on  communications  law,  and  is  associ- 
ated with  Segal,  Smith,  and  Hennessey. 


New  York  to  Philadelphia.  The  program 
was  picked  up  at  the  Yankee  Stadium, 
New  York,  and '  relayed  by  microwave 
relays  successively  to  WNBT  (Empire 
State  Building,  New  York),  WPTZ, 
Wyndmoor,  Penna.,  and  the  Fox-Phila- 
delphia Theatre,  a  distance  of  about  100 
miles.  From  the  roof  of  the  theatre  the 
program  was  run  to  the  receiving  and 
projecting  equipment  by  coaxial  cable. 
The  reaction  of  the  audience  in  the 
2400-seat  theatre  was  described  as  highly 
enthusiastic. 

Theatre  Equipment  Required 

On  April  4,  1949,  the  RCA-Fox-War- 
ner  system  was  demonstrated  before  the 
SMPE  at  the  Statler  Hotel,  New  York, 
the  programs  being  relayed  in  part  via 
balanced  telephone  wires  from  the  Em- 


12 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


He  makes  the  most 
of  moonlit  moments  •  •  • 


IT'S  mighty  important  to  star  . . .  direc- 
tor . . .  movie-goer  ...  to  have  this  moon- 
lit moment  come  alive  upon  the  screen. 

And  when  it  does — in  all  its  subtlety 
of  mood  in  light  and  shadow — the  cred- 
it's due  in  no  small  measure  to  the  im- 
portant contribution  of  the  laboratory 
control  engineer. 

For  his  knowledge  of  photochemistry, 
his  "eye"  for  photographic  quality  .  .  . 


his  vigilant  control  of  printing  density 
and  contrast  ...  do  much  to  make 
moonlight  footage  look  like  moonlight, 
and  help  to  bring  out  the  best  in  every 
frame  of  film. 

Quality  of  film  contributes,  too;  and 
this  important  assistance  the  laboratory 
control  engineer  is  sure  of  when  he 
works  with  the  famous  Eastman  family 
of  motion-picture  films. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,     N.    Y. 

J.    E.    BRULATOUR,    INC.,    DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •     HOLLYWOOD 


RCA  Color  Converter   Using  Small   Projection   Kinescopes  and   Refractive  Optics 


Direct-view  picture  reproducing  system  developed  by  RCA 
for  color  Tv  uses  three  kinescopes  and  two  dichroic  mirrors. 
In  operation,  the  red  components  of  the  scene  appear  on  the 
lower  tube  and  are  reflected  to  the  viewer  by  the  right  hand 
mirror.    Blue  components  are  formed  on  the  middle  tube  and 


are  reflected  by  the  left  hand  mirror  through  the  right  mirror 
to  the  viewer.  The  green  components  created  on  the  left 
upper  tube  pass  straight  through  the  two  mirrors  to  join  the 
other  two  color  versions  of  the  scene  to  give  the  viewer  the 
effect  of  the  combination  of  the  three  colors. 


pire  State  Building  to  the  hotel.  The 
RCA-Fox- Warner  group  has  also  de- 
veloped intermediate-film  equipment. 

The  equipment  required  for  theatre 
Tv  falls  into  two  general  categories:  that 
which  is  installed  in  the  theatre  for  re- 
ceiving the  program  and  projecting  it  to 
the  screen,  and  the  equipment  used  out- 
side the  theatre  for  pickup  of  programs 
and  relay  to  the  theatre. 

The  first  problem  undertaken  was  the 
development  of  theatre  Tv  equipment. 
These  units  have  now  reached  the  point 
where  two  systems  are  now  ready  for 
commercial  use:  the  direct  (or  instan- 
taneous-projection system)  and  the  in- 
termediate-film (or  film-storage )  system.2 

The  direct-projection  system,  devel- 
oped by  the  RCA-Fox-Warner  group, 
consists  of  (1)  the  receiver-projector, 
which  includes  a  projection  cathode-ray 
tube  as  the  source  of  the  light  image, 
and  the  optical  system  which  projects 
the  image  to  the  screen  by  a  reflective 
process;    (2)    a  viewing   screen;    (3)    a 


(2)  Electronic-storage,  as  opposed  to  film- 
storage,  methods  are  also  under  develop- 
ment, using  the  Skiatron  tube  (or  P10 
phosphor)  and  the  so-called  Swiss  or  AFIF 
Method,  developed  by  Dr.  F.  Fischer  of  the 
Swiss  Federal  Institute  of  Technology.  Elec- 
tronic-storage methods,  however,  are  not  ex- 
pected to  be  available  for  commercial  use 
in  the  near  future. 


Tv  control  console;  and  (4)  a  power- 
supply  rack  and  high-voltage  power 
unit.3  If  the  Tv  program  is  brought  to 
the  theatre  by  a  microwave  relay  sys- 
tem, the  theatre  installation  will  also  in- 
clude a  receiving  antenna,  receiver,  and 
a  transmission  line  to  carry  the  program 
from  the  antenna  to  the  receiver. 

Data  on  RCA's  Latest  Equipment 

RCA's  latest  projector  utilizes  a  12- 
inch  cathode-ray  picture  tube  inclosed 
in  a  barrel  about  the  size  and  appear- 
ance of  a  Bendix  home  washing  machine. 
The  optical  system  enclosed  in  the  same 
barrel  employs  a  21-inch  spherical  mir- 
ror and  a  correcting  lens,  employing  the 
Schmidt-type  optical  system. 

As  installed,  the  picture  tube  faces  the 
rear  of  the  theater  and  projects  the  pic- 
ture on  the  spherical  mirror  which  re- 
flects it  toward  the  screen.  The  picture 
passes  through  the  correcting  lens  on  its 
way  to  the  screen.  The  picture  tube 
operates  with  80,000  volts,  as  compared 
with  the  9000  volts  used  in  most  home 
Tv  receivers.  The  optical  system  is  cap- 
able of  projecting  a  screen  image  18  x 


(3)  A  similar  direct  projection  system 
has  been  developed  in  England.  See 
A.  G.  D.  West,  "Development  of  Theatre 
Television  in  England,"  /.  Soc.  Mot.  Pict. 
Eng.,  vol.  51,  pp.  127—169;  August,  1948. 


24  feet,  which  is  larger  than  the  average 
motion  picture  screen. 

The  entire  projector  unit  weighs  about 
180  pounds  and  is  designed  for  installa- 
tion either  suspended  from  the  balcony 
or  mounted  on  a  platform  in  front  of 
the  theater  mezzanine,  rather  than  in  the 
regular  projection  room.  The  "throw  dis- 
tance" can  be  varied  from  45  to  80  feet. 

RCA  plans  to  manufacture  pilot 
models  before  the  end  of  1949  for  sale 
to  theatres  at  a  price  under  $25,000.  The 
first  such  unit  has  been  ordered  for  in- 
stallation in  the  Fabian  Fox  Theatre  in 
Brooklyn,  New  York.  The  installation  of 
microwave  receiving  equipment  and  a 
transmission  line  would  cost  approxi- 
mately $3500  at  present  prices. 

Intermediate-Film  System 

The  viewing  screen  is  an  important 
element  of  the  direct-projection  system. 
The  cathode-ray  tube,  which  is  the  light 
source  for  projection  Tv,  at  this  stage  of 
development  cannot  compete  with  the 
carbon  arc  which  is  the  light  source  in 
conventional  motion  picture  projectors. 
Thus,  while  standard  motion  picture 
screens  are  generally  not  directional  in 
distributing  the  light,  much  research  has 
been  devoted  to  the  development  of  di- 
rectional screens  for  Tv. 

The  Paramount  intermediate-film  sys- 
tem consists  of  (1)  receiving  equipment, 
(2)     a     specially     developed     recording 


14 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


camera,  (3)  rapid  film-processing  equip- 
ment, capable  of  developing  film  in  less 
than  a  minute,  and  (4)  a  conventional 
35-mm  motion  picture  projector.  If  the 
program  is  received  over  microwave  re- 
lay, receiving  equipment  and  a  trans- 
mission  line  must  be  installed. 

The  receiving  equipment  is  contained 
in  one  unit,  which  houses  both  video  and 
audio  equipment,  and  high-  and  low- 
voltage  power  supplies. 

The  receiver  utilizes  a  10-inch  cathode- 
ray  tube,  aluminum-backed  and  with  a 
flat-face  screen,  from  which  the  picture 
is  photographed.  A  15-inch  cathode-ray 
tube  is  provided  for  monitoring  purposes. 
The  special  recording  camera  utilizes  an 
electronic  shutter,  rather  than  a  me- 
chanical one,  and  is  synchronized  at  the 
standard  film  rate  of  24  frames  per  sec- 
ond. Twenty  frames  before  exposure  of 
the  picture  the  sound  track  is  impressed 
on  the  film. 

High-Speed  Film  Processing 

One  of  the  amazing  features  of  this 
system  is  the  high-speed  film-processing 
unit,  into  which  the  film  passes  by  chute 
from  the  recording  camera.  The  film  is 
lead  by  vertical  chutes  into  solutions 
which  develop,  fix,  and  wash  it,  and  into 
a  compartment  which  dries  it  in  a  maxi- 
mum period  of  66  seconds.  The  proc- 
essed film  either  may  be  wound  on  reels 
or  fed  directly  to  the  conventional  35-mm 
film  projector  by  chute.  The  equipment 
requires  a  room  of  about  10  by  20  feet 
floor  space,  which  is  usually  located  di- 
rectly above  the  projection  room. 

It  has  been  reliably,  and  probably  con- 
servatively, stated  that  the  cost  of  the 
receiver,  camera,  and  processing  unit 
will  be  approximately  $35,000,  plus  in- 
stallation. Units  of  this  type  have  been 
installed  in  Paramount  theatres  in  New 
York,  Chicago,  and  Los  Angeles.  It  is 
likely  that  the  price  of  the  three  units 
may  be  in  the  $15,000  to  $20,000  range, 
plus  installation,  when  available  in  com- 
mercial quantities.  The  microwave  re- 
ceiving equipment  and  transmission  line 
would  add  an  additional  $3500. 

Theatre  Tv  equipment  has  not  yet  at- 
tained the  perfection  of  class  A  motion 
pictures,  although  engineering  opinion 
supports   the    conclusion   that    such    per- 


(4)  The  20th  Century-Fox  report  to  the 
FCC  of  its  experimental  theatre  Tv  opera- 
tions contained  the  tentative  conclusion : 
"The  quality  of  a  television  picture  having 
a  total  of  525  scanning  lines  per  frame  and 
a  horizontal  resolution  in  excess  of  600 
lines,  with  good  picture  contrast  ratio,  will 
approach  that  of  35-mm  professional  motion 
picture  film,  provided  there  is  good  halftone 
reproduction,  accurate  line  interlace,  and 
specified  minimum  of  geometric  distortion. 
Such  a  value  of  horizontal  resolution  would 
require  a  video  band-pass  of  between  7  and 
8  megacycles." 


fection  is  attainable.  However,  20th 
Century-Fox  recently  advised  the  FCC 
that  in  its  opinion  "the  generation  of  a 
theatre  Tv  picture  of  suitable  quality  is 
not  only  possible  but   practical."4 

The  final  arbiter  of  picture  quality  is 
the  audience,  and  theatre  Tv  has  been  re- 
ceived favorably  by  the  public.  There  is 
some  danger  that  in  waiting  for  technical 
perfection,  the  motion  picture  industry 
may  lose  the  opportunity  to  secure  the 
radio  frequencies  and  other  transmission 
facilities  that  would  make  theatre  Tv 
possible. 

Distributing  Theatre  Tv  Programs 

The  most  critical  and  urgent  problems 
facing  the  proponents  of  theatre  Tv  in- 
volve determination  of  methods  and 
means  for  transmitting  programs  to  the 
theatres.    It  is  well  known  that  Tv  pro- 


grams may  be  transmitted  by  radio  re- 
lays, by  coaxial  cable,  and  by  telephone 
wires  for  short  distances.  The  oppor- 
tunity to  use  these  avenues  of  program 
distribution  cannot  be  had  merely  for 
the  asking.  The  use  of  radio  relays  re- 
quires approval  by  the  FCC.  The  use  of 
coaxial  cable  and  telephone  wires  re- 
quires the  co-operation  of  A.T.&T.  and 
the  Bell  System. 

Wherever  theatre  Tv  applies  for  trans- 
mission facilities  it  must  prove  a  demand 
for  the  facilities  and  it  must  overcome 
strong  competition  for  the  same  facilities 
by  broadcast  Tv  networks  and  stations, 
and  by  other  users  of  the  same  facilities. 

Theatre  Tv  may  be  carried  out  as  an 
independent  enterprise  by  one  theatre 
which  provides  or  obtains  all  of  its  own 
(Continued  on  page  32 J 


Early  Photographic  Collection  Recalls  Governor's  Bet 


AN  HISTORIC  photographic  collec- 
tion is  a  reminder  of  a  governor's 
wager  that  a  galloping  horse  lifts  all 
four  feet  off  the  ground  at  once.  The 
collection  is  part  of  the  equipment  used 
by  Eadweard  Muybridge,  a  photographer 
of  the  1870's,  which  will  be  shown  at 
George  Eastman  House,  the  photographic 
museum  in  Rochester,  N.  Y.,  which  was 
opened  to  the  public  this  fall. 

The  collection  was  made  available 
through  the  generosity  of  Dr.  George 
Nitzsche,  recorder  emeritus  of  the  Uni- 
versity of  Pennsylvania. 

Governor  Leland  Stanford  of  Califor- 
nia made  the  bet;  Muybridge  tackled  the 
tough  photographic  job.  After  many 
trials,  the  latter  lined  up  a  number  of 
cameras  along  a  track.  Eventually  he 
attached  strings  to  electric  switches  that 
controlled  the  camera  shutters.  When  a 
horse  galloped  past,  it  broke  the  strings 
one  after  another.  The  shutters  were 
released  and  negatives  made  in  a  series. 
The  photographs  proved  that  Governor 
Stanford  was  right.  The  feet  were  off 
the  ground  during  the  gallop. 

Filled  Still-Motion  Picture  Gap 

Muybridge  was  a  pioneer  in  instan- 
taneous photography.  His  work  fills  the 
gap  between  still  and  motion  picture 
history.  While  he  set  out  to  eliminate 
motion  by  stopping  it  in  pictures,  in  1880 


he  also  projected  photos  intermittently. 
This  produced  motion  on  the  screen. 
Thus  he  anticipated  the  motion  picture. 

His  projected  pictures  of  horses  in 
motion  amazed  audiences.  The  San  Fran- 
cisco Call  of  May  5,  1880,  reported  that 
"nothing  was  wanting  but  the  clatter  of 
the  hoofs  upon  the  turf  and  an  occasional 
breath  of  steam  from  the  nostrils,  to 
make  the  spectator  believe  that  he  had 
before  him  genuine  flesh-and-blood 
steeds." 

Later  Muybridge  went  to  Philadelphia 
where  he  continued  his  work  at  the 
University  of  Pennsylvania  from  1883  to 
1885.  Here  he  perfected  his  equipment. 
He  also  turned  to  use  of  the  new  dry 
plates  for  shorter  exposures.  The  results 
of  his  work  were  published  in  a  series 
of  781  illustrations  on  animal  locomotion. 
For  his  pictures  he  used  horses  and 
animals  of  all  kinds  from  the  Philadel- 
phia zoo  as  well  as  human  models. 

Muybridge's  photography  at  Philadel- 
phia was  done  outdoors  against  a  black 
background.  Opposite  the  background 
he  had  a  battery  of  24  cameras.  A  cam- 
era in  the  collection  at  Eastman  House 
is  one  of  these.  Also  in  the  collection 
are  Muybridge's  notebooks,  13  albums 
containing  a  large  number  of  his  dupli- 
cate negatives,  and  an  album  of  albumen 
prints  which  are  considered  to  be  the 
best  of  his  work. 


The  clincher.    Muybridge  photographs  like  these  proved  that  a  horse  lifts  all  feet  off  the  ground 
at  once  in  a  gallop,  winning  a  bet  for  Governor  Stanford  of  California  in  1870. 


INTERNATIONAL  PROJECTIONIST 


November  1949 


15 


BEARING  on  the  two  excerpts  from 
IP  shown  within  rules  at  right,  both 
Eastman  Kodak  Co.,  and  Robert  A. 
Mitchell — no  less  than  the  projectionist 
craft  generally — should  find  the  ap- 
pended comment  and  accompanying 
photographs  of  more  than  passing  in- 
terest. 

First,  however,  the  writer  expresses 
his  sincere  thanks  to  Max  Scharnberg, 
Cine  Engineer  and  Instructor,  Teknolo- 
gisk  Institut,  Copenhagen,  Denmark,  for 
the  two  highly  interesting  photographs 
here  reproduced. 

Water  for  Film  Fires 

Figure  1  destroys  many  cherished  il- 
lusions about  the  ability  of  water  to 
put  out  film  fires.  Burning  film  can 
sometimes  be  extinguished  by  liberally 
dousing  it  with  water — but  not  always. 
If  the  reel  is  burning  vigorously,  it  may 
continue  to  burn  even  if  it  be  dropped 
into  a  tub  of  water,  as  this  amazing 
photograph  shows.  „ 

This  spectacular  demonstration  was 
performed  at  the  Institute  of  Technology 
in  Copenhagen  for  the  benefit  of  projec- 
tionist license  applicants. 

Take  a  good  look  at  Fig.  2  and  imag- 
ine a  fire  like  that  in  your  projection 
room!  In  the  event  of  such  an  accident, 
the  projectionist  should  never  attempt  to 
fight  the  fire,  but: 

1.  Switch  on  the  house  lights. 

2.  Drop  the  port  shutters. 

3.  "Kill"  the  arc. 

4.  Get  out  of  the  projection  room. 

The  projector  magazine  in  this  pic- 
ture is  fitted  with  the  "Dawesnets,"  fa- 
miliar to  projectionists  who  operate  the 
Ernemann,  Bauer,  and  Euro  projectors, 
the  Aga  (Swedish)  the  Philips  (Dutch), 

FIG.  1.  Nitrate  film  burning  under  water. 


"Safety  film  avoids  the  'principal  hazard 
of  nitrate  film.  Nitrate  film  burns  very 
rapidly  indeed.  When  a  roll  is  thoroughly 
ignited,  it  cannot  be  extinguished  with  a 
fire  extinguisher  nor  even  by  immersion  in 
a  bucket  of  water.  This  is  because  it  carries 
its  own  oxygen  supply  within  itself  in  the 
form  of  the  nitrate  group." 

Excerpt  from  "Questions  and  Answers 
on  Safety  Film";  IP,  Sept.,  1949,  p.  14. 

"Regardless  of  what  Eastman  Kodak  Co. 
says  about  film  burning  under  water  (see 
foregoing  excerpt),  most  celluloid  factories 
rely   on   nothing   but  water   to   combat   fires 


which  may  occur.  I  once  set  afire  outdoors 
a  full  2000-foot  reel  of  film,  and  put  it  out 
by  simply  throwing  a  bucket  of  water  on  it. 
I  should  like  to  try  dropping  a  blazing  reel 
into  a  tub  of  water,  but  I  have  only  a  few 
reels  of  my  own  left.  .  .  . 

"Water,  to  be  effective,  must  be  applied 
in  a  powerful  continuous  stream.  Sprinkling 
systems  are  of  no  value  because  they  do  not 
apply  sufficient  water  to  cool  the  film  below 
the  ignition  temperature." 

Excerpt  from  "Fire  Extinguishers  in 
Projection  Rooms"  by  Robert  A.  Mit- 
chell; IP  for  Oct..  1949,  pp.  12,  30. 


Film  Fire  Characteristics 

Will  film  burn  when  totally  submerged  in  water? 
It  certainly  will! 

By  RICHARD  D.  MARKS 


and   the   Mikroteknika    (Italian),   mech- 
anisms. 

The  Dawesnet,  required  by  German 
regulations,  consists  of  an  opening  on 
each  side  of  the  magazine,  each  of  a  size 
6  per  cent  of  the  area  of  one  side, 
and  covered  over  with  a  wire  screen 
(like  mosquito  netting)  having  144 
meshes  per  square  centimeter.  This 
construction  explains  why  the  flames  are 
issuing  from  both  sides  of  the  magazine 
shown  in  the  picture. 

Minimum  Factor  of  Safety 

In  regard  to  the  Dawesnet  as  a 
"safety"  device,  a  top-flight  European 
motion   picture   technician   states: 

The  intention  is  that  the  film  in  the 
magazine  is  to  have  a  supply  of  air  in 
order  that  it  burn  with  a  bright  flame, 
thereby  avoiding  the  accumulation  of 
explosive  gas  in  the  projection  room. 
The  net,  furthermore,  ought  to  prevent 
the  flames  from  issuing  from  the  maga- 
zines.; but,  unfortunately,  there  arises 
so  great  a  pressure  that  flames  up  to  2 
meters  (6  feet)  jump  out  through  the 
net  and  set  fire  to  the  film  in  the  other 
projector  and  raze  the  whole  projection 
room." 

It  is  easy  to  see  why  the  wire  screen 
of  the  Dawesnet  fails  to  confine  the 
fire.  A  reel  of  film,  when  burning,  may 
attain  a  temperature  which  produces 
enormous  volumes  of  such  combustible 
gases  as  carbon  monoxide,  hydrogen,  and 
methane. 

Now,  it  is  possible  to  conjecture  with 
some  accuracy  that  the  wire  Dawesnet 
attain  bright-red  heat  (of  the  order  of 
800°  C.)  in  about  15  seconds  from  the 
time  of  outbreak  of  fire  in  a  magazine, 


and,  further,  that  the  net  becomes  even 
hotter  than  this  before  the  fire  has  sub- 
sided. But  even  red  heat  is  a  sufficiently 
high  temperature  to  ignite  the  com- 
bustible gases.  Carbon  monoxide  ignites 
at  645°  C.  in  air  under  standard  baro- 
metric pressure;  hydrogen  at  585°  C; 
and  methane  at  650°  C. 

Projector  magazines  of  American  de- 
sign are  totally  enclosed  and  are  so  con- 
structed that  the  doors  unlatch  and  fly 
open  when  the  gases  from  burning  film 
attain  a  certain  degree  of  pressure.  Se- 
rious explosions  may  result  when  the 
doors  fail  to  open*  (see  footnote  at  end  of 
article). 

Several  correspondents  in  foreign 
countries  have  expressed  doubts  that 
American  magazines  are  entirely  safe, 
and  they  have  asked  the  writer  if  the 
doors  are  made  to  open  at  a  definite  ga& 
pressure.  Of  course,  projector  maga- 
zines are  not  absolutely  air-tight,  but 
it  does  seem  only  fair  to  offer  these  cor- 
( Continued  Col.  1,  foot  of  next  page) 

FIG.  2.  Film  fire  in  a  projector  magazine. 


16 


INTERNATIONAL  PROJECTIONIST 


November  1949 


m 


To  the  Editor  of  IP: 

On  several  occasions  I  have  noted  in  IP 
that  American  projectionists  cite  certain 
long-run  prints,  some  of  which  are  said  to  be. 
run  300  or  400  times.  I  wish  you  would 
carefully    examine    the    enclosed    clips    from 


W 


Clip  of  Charlie  Chaplin 
print  which,  32  years 
old,  was  recently  pro- 
jected 150  times  within 
one  week. 


two  "original''  Charlie  Chaplin  films — "The 
Immigrant"  and  "1  A.M."  These  prints — 
now  32  years  old! — were  run  a  total  of  150 
times  in  two  different  theatres  here  recently. 
During  the  entire  run  I  had  no  stops  or 
trouble  of  any  kind. 

Notice   how   pliable    and    soft   these    clips 

still   are,  and   also   the  complete  absence  of 

scratching,   embossing   or   any   other    defect. 

Percy  T.  Mollek 

Melbourne,  Australia 

To  the  Editor  of  IP: 

I  am  somewhat  troubled  by  the  tone  of 
your  Monthly  Chat  in  IP  for  October  (p.  3). 

respondents  some  assurance  that  the 
magazine  doors  will  open  if  film  burns 
in  the  magazines — particularly  in  view 
of  the  fact  that  the  use  of  American 
equipment  may  be  vetoed  unless  they 
are  convinced  on  this  point. 

We  want  American  equipment  to  be 
used  in  every  country,  not  because  it 
is  American,  but  because  it  is  the  best 
equipment  in  the  world.  Projector 
manufacturers  and  exporters ,  of  equip- 
ment are  invited  to  contribute  their 
opinions  on  magazine  construction  to 
IP  for  the  benefit  of  skeptical  projection 
engineers  and  safety  officials  overseass. 


*  Note:  This  statement  will  occasion 
many  an  arched  eyebrow,  and  it  has  al- 
ready induced  strong  disagreement  from 
two  projector  manuafcturers,  who  point  out 
that  it  would  take  one  whale  of  a  lot  of 
pressure,  even  exceeding  that  produced  by 
a  burning  full  double  reel,  to  accomplish 
such  a  result.  We'll  let  the  statement  stand 
as  written,  however,  in  the  hope  that  some 
reader  will  have  something  interesting  to 
say  anent  this  topic. — Ed. 


-. 


Have  you  found  it  impossible  to  arrange 
with  the  equipment  manufacturers  that  panel 
discussion  for  which  you  originally  seemed 
to  have  such  high  hopes.  I  hope  not;  but 
the  phrase  "abortive  effort"  in  your  Chat 
leads  me  to  believe  that,  for  some  reason  or 
other,  you  have  given  up  on  the  project. 

It  does  seem  strange  that  the  manufac- 
turers, with  every  means  for  research  and  test 
at  their  disposal,  should  come  forth  with 
mere  statements  of  opinion  instead  of  indis- 
putable facts.  Anybody  can  express  an 
opinion,  even  a  person  who  has  no  clear 
understanding  of  the  matter  under  considera- 
tion. I  should  like  to  see  IP  prosecute  this 
panel  session  matter  vigorously,  so  that  we 
could  come  up  with  the  correct  answer. 

Richard  Vaughan 
San  Francisco,  Calif. 

IP's  offer  to  handle  all  details  of  organ- 
izing such  a  panel  session  —  providing 
quarters,  making  a  transcript  of  the  pro- 
ceedings, in  fact,  all  necessary  arrange- 
ments—  still  stands.  IP  can  only  invite, 
only  propose;  the  real  initiative  must 
come  from  the  manufacturers  them- 
selves.— Ed. 

To   the  Editor  of  IP: 

I  was  very  much  interested  in  the  article 
"An  Improved  Concentrated-Arc  Light," 
which  appeared  on  page  10  of  your  October 
issue,  but  I  am  not  quite  sure  just  how  this 
lamp  operates  —  that  is,  how  it  is  started,  and 
what  happens  once  it  is  operating. 

Roy  McAllister 
Los  Angeles,  Calif. 

Western  Union's  new  open-air  Telco- 
arc  lamp  emits  light  at  a  brilliance  of 
130  candles  per  sq.  mm  from  a  thin  sur- 
face of  molten  zirconium  metal  (1  in 
the  accompanying  illustration)  at  the 
end  of  specially  prepared  electrodes  (2). . 
The  electrodes  are.  made  of  nickel,  filled 
to  a  depth  of  %  inch  with  a  mixture. of 
87  per .  cent  zirconium  oxide,  8.7  per 
cent  nickel,  and  4.3  per .  cent  other 
materials. 

These  tiny  electrodes  are  warranted  by 
W.  U.  to  operate  continuously  for  37 
hours. 

The  lamp  is  started  by  bringing  to- 
gether the  two  electrodes  so  that  the 
zirconium  oxide  caps  are  touching 
(similar  to  a  carbon  "freeze")  and  then 
the  power  is  turned  on.  Once  the  arc  is 
"struck,"  a  high-voltage  pulse  is  pro- 
vided from  an  inductor  and  vacuum 
switch,  or  a  high-voltage  transformer,  to 
form  the  active  zirconium  surface  which 
is  the  light  source  of  the  lamp.  After 
the   active   surface  is   formed,   the  lamp 


will  operate  at  its  normal  rating  of  55 
volts. 

Stability  of  the  arc  is  provided  through 
the  use  of  a  differentially-coiled  electro- 
magnet which  exerts  control  in  direct  pro- 
portion to  the  lamp  current  in  a  vertical 
direction,  and  by  a  permanent  magnet  in 
the  horizontal,  or  lateral,  direction. 

Arc-spacing  is  controlled  by  micro- 
meter screws  (5)  which  require  adjust- 
ment only  once  every  half-hour  during 
operation  —  similar  to  the  carbon-arc  gap 
with  which  projectionists  are  familiar. 
It  is  also  possible  to  provide  automatic 
arc-spacing  control  through  an  electrical 
control  mechanism. 


The  W.U.  concentrated-arc:  1,  Zirconium  metal 
surface  (active  luminous  area);  2,  Specially 
prepared  electrodes;  3,  Differentially  coiled 
electro  magnet  with  wide  pole  pieces  for  ver- 
tical arc  stream  control;  4,  Permanent  magnet 
for  lateral  arc  stream  control;  5,  Micrometer 
screw    control    for    adjustment    of    electrodes. 

Altec  Service  Personnel  Increased 

An  increase  in  Altec  Service  contracts  to 
an  all-time  high  in  company  history  has  re- 
sulted in  promotions  and  additions  to  the 
staff  of  men  who  are  well-known  in  projec- 
tion circles.  Ralph  Kautzky  has  been  ad- 
vanced from  Broadway  (New  York  City) 
service  inspector  to  New  York  suburban  field 
manager,  taking  in  New  Jersey  and  upstate 
Ne.w  York.  J.  I.  Mather,  formerly  field  man- 
ager in  Detroit,  becomes  field  manager  in 
the  Washington,  Maryland,  and  Virginia 
areas,  with  a  special  assignment  under  the 
new  Altec  contract  with  the  U.  S.  Navy. 

Also  under  the  Navy  contract,  R.  W. 
Fuller,  formerly  with  the  Electronic  Division, 
has  been  added  to  the  Boston  staff;  L.  G. 
Schock,  formerly  with  Warners  in  Atlantic 
City,  goes  to  Providence,  R.  I.;  W.  J.  Sirms, 
another  former  Warner  man  in  Philadelphia 
has  joined  Altec  in  that  area;  N.  Markanich, 
temporarily  in  Newport  News,  formerly  of 
Scranton;  Ernest  Theiss  in  Washington,  and 
Adolph  H.  Baus,  Jr.,  formerly  with  Sperry 
Gyroscope,   to   Brooklyn. 

Fred  Pheiff,  formerly  New  York  suburban 
field  manager,  has  been  promoted  to  duty  in 
Altec's  New  York  City  headquarters. 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


17 


IN  THE 

SPOTLIGHT 


By 

HARRY 

SHERMAN 


Your  attention  is  directed  to   the   article   on  Page   5   of  this   issue 


WITHOUT  detracting  one  bit  from 
the  swell  job  done  by  President 
Philip  Murray  and  his  CIO  aides  in 
effecting  a  settlement  with  the  steel  com- 
panies, which  gives  steel  workers  vastly 
increased  social  benefits,  there  is  one 
point  on  which  we  think  the  CIO  leader 
is  in  error.  Mr.  Murray  was  quoted  as 
saying  that  the  settlement  was  the  "most 
outstanding  achievement  of  its  kind  at- 
tained by  any  union  through  voluntary 
collective  bargaining  in  this  or  any  other 
country." 

When  Mr.  Murray  uses  the  phrase 
"voluntary  collective  bargaining,"  he 
means  that  the  deal  was  made  by  direct 
negotiation  between  union  and  employer, 
without  government  intervention  of  any 
kind. 

Now,  we  have  a  union  right  in  our 
own  IA  which  more  than  a  year  ago 
(Sept.  1,  1948)  achieved  through  volun- 
tary collective  bargaining,  and  without  a 
strike,  a  welfare  set-up  which,  while  not 
matching  in  scope  the  70,000  steel  work- 
ers' settlement,  certainly  was  a  pioneer- 
ing  achievement — the  more   difficult   be- 


cause it  affected  a  field  which  properly 
may  be  considered  as  being  more  on  the 
"service"  rather  than  on  the  straight 
"industrial"  side,  such  as  steel  produc- 
tion. We  refer  to  the  Chicago  Local  110 
general  welfare  plan,  which  also  includes 
pensions. 

In  passing,  it  might  be  remarked  that 
the  steel  workers'  pensions  will  be  re- 
duced by  whatever  payments  they  re- 
ceive under  the  Federal  Social  Security 
Law,  which  restriction  definitely  does 
not  apply  to  the  Local  110  arrangement. 
Incidentally,  the  figures  for  the  first  full 
year  of  operation  of  the  Local  110  plan 
have  now  become  avail?ble  and  are  pre- 
sented here: 

Receipts   $397,671.84 

Disbursements    217,819.79 

Cash  on  Hand $179,852.05 

We  understand  that  President  Walsh  is 
now  negotiating  for  the  establishment  of 
a  general  welfare  plan,  including  a  pen- 
sion arrangement,  for  the  motion  picture 
studio  workers.  More  later  on  this. 


25TH  ANNIVERSARY  PARTY  OF  LONG  ISLAND  (N.  Y.)  LODGE  67,  TMA 


Seated  (I.  to  r.):  Mrs.  Mabel  Lloyd,  Mother  of  all  TMA  auxiliaries;  Phil  Hitter  and  Mrs.  Hitter; 

Mrs.  Weidner,  Mrs.  Nadel,  Mrs.  Adelson,  Mrs.  Pantizis,  Mrs.  Underhill,  and  Mr.  Adelson.     Center 

row   (standing):  Charles   Eichhorn,  T.   J.   Lloyd,  L.    Burns,  J.   Weidner,  A.  Silverman,   N.    Nadel, 

H.  Felsinger,  S.  Fink,  and  J.  Barish.  Back  row:  Charles  Muller  and  W.  W.  Friedman. 


•  Lester  Isaac,  director  of  projection 
and  sound  for  Loew's,  Inc.,  has  been 
shuttling  back  and  forth  between  N.  Y. 
City  and  the  West  Coast,  supervising  the 
projection  installations  for  the  newly- 
remodeled  State  Theatre,  Los  Angeles, 
and  the  Warfield  Theatre,  San  Francisco. 
These  houses  are  now  under  the  manage- 
ment of  Loew's  Theatres,  Inc.,  and  will 
be  supervised  as  integral  units  of  the 
national  set-up. 

•  Fresno,  Calif.  Local  599  recently  hon- 
ored four  of  its  members  with  life-mem- 
bership cards  for  outstanding  services 
rendered  the  Local.  Recipients  of  the 
awards  were  Grover  Miller,  member  of 
Local  599  since  1915  and  business  rep- 
resentative for  15  years  prior  to  his  re- 
tirement last  year;  Frank  Bell,  who 
served  as  financial  secretary  for  20  years ; 
Harry  Wolfe,  member  since  1917,  and 
Homer  Elias,  who  has  been  a  member  of 
the  Local  since  1919.  Both  Wolfe  and 
Elias  served  in  various  official  capacities. 

•  Ground  was  broken  last  month  for 
Los  Angeles  Local  150's  new  home.  The 
early-morning  ceremonies,  conducted  by 
Frank  Sawyer,  the  oldest  card-holding 
member  of  the  Local,  attracted  a  fine 
turnout.  The  usual  roundup  of  "sidewalk 
superintendents"  are  now  gathered  daily 
at  1800  S.  Vermont  Avenue,  the  future 
address  for  Local  150  headquarters. 

•  Most  of  us  are  familiar  with  the  double- 
talking  politician  who,  while  running  for 
public  office,  makes  a  bid  for  the  labor 
vote  by  professing  his  staunch  support 
of  organized  labor.  Labor  is  wise  to  these 
wily  individuals  and  is  pretty  careful  to 
check  a  candidate's  record  of  past  per- 
formances before  lending  him  support. 

All  this  leads  to  the  case  of  Louis  A. 
Johnson,  our  Secretary  of  National  De- 
fense (who  is  rumored  to  be  a  1952 
presidential  candidate),  vs.  IA  Local  270, 
Clarksburg,  W.  Va.  We  understand  that 
Mr.  Johnson  is  an  important  stockholder 
in  the  Clarksburg  Theatre  Corporation 
and  directs  its  policies.  Although  the  offi- 
cials of  Local  270  have  tried  repeatedly 


18 


INTERNATIONAL  PROJECTIONIST 


November  1949 


during  the  past  years  to  organize  the 
corporation's  theatres,  they  claim  that 
Mr.  Johnson's  hostility  has  prevented 
them  from  doing  so.  It  is  also  the  Lo- 
cal's contention  that  the  CIO  set-up  rec- 
ognized by  the  corporation  is  nothing  but 
a  company  union  and  as  such  does  not 
truly  represent  the  best  interests  of  its 
employes. 

•  Hi  Berling,  former  business  representa- 
tive for  Local  380,  Oklahoma  City,  re- 
cently won  a  new  Buick  car  in  a  Turtle 
Derby  sponsored  by  Variety  Club  Tent 
22.  He  entered  five  turtles  in  the  derby- 
Mo,  Sol,  Sid,  Abe,  and  Izzy — all  named 
for  close  friends.  "Izzy"  came  through 
with  flying  colors — while  Hi  hit  the  jack- 
pot. 

•  Under  the  management  of  Roy  Thomp- 
son, member  of  Local  88,  Waterbury, 
Conn.,  Hogan's  Irish  House  on  West  52 
Street,  N.  Y.  City,  has  become  a  popular 
rendezvous  for  IA  men,  local  and  visit- 
ing. President  Walsh  and  many  other 
IA  executives  are  frequent  patrons — a 
pretty  sure  indication  that  Thompson  is 
delivering  top-rate  service  and  food. 

•  Ralph  Root,  Sr.,  business  representa- 
tive for  Local  236,  Birmingham,  Ala.,  is 
mighty  proud  of  his  offspring,  Ralph,  Jr., 
and  for  an  excellent  reason.  Root,  Jr., 
now  25  years  old,  served  three  years  with 

the  U.  S.  Army  Sig- 
nal Corp  in  World 
War  II,  and  is  the 
proud  possessor  of 
campaign  ribbons 
denoting  service  in 
the  European,  Af- 
rican and  Middle 
East  invasions. 

A  student  at 
Georgia  Tech, 
Ralph,  Jr.  graduates 
shortly  with  a  B.S. 
in    Electrical    Engi- 


Ralph  Root,  Jr. 


neering.      He 


prominent  in  extra-curricular  activities, 
being  president  of  the  "Wand  and  Rab- 
bit Club,"  and  public  relations  officer  for 
the  "Latin  American  Club,"  the  latter 
being  composed  of  students  from  South 
America.  He  is  a  member  of  the  Georgia 
Tech  Chess  Team  and  a  student  member 
of  the  Institute  of  Radio  Engineers. 

Ralph,  Jr.  was  always  interested  in  all 
phases  of  projection  work  and  became  a 
member  of  Local  236  in  1946.  He  in- 
forms us  that  the  copies  of  IP  sent  to  the 
college  reference  library  get  a  pretty  thor- 
ough going-over  each  month  and  rate 
high  on  the  request  list. 

•  The  sudden  passing  of  Sid  Burton, 
member  of  Los  Angeles  Local  150  since 
1915  and  cop-flight  projection  man,  sad- 
dened his  many  friends  in  the  Alliance. 
Sid,  loved  and  respected  by  all  who  came 


in  contact  with  him,  was  never  known  to 
turn  down  a  needy  friend.  He  served  the 
Local  in  various  official  capacities  and 
directed  many  of  its  educational  activi- 
ties. Sid  was  buried  with  Masonic  serv- 
ices. We  sympathize  deeply  with  his  sur- 
vivors. 

•  Shirley  Brown,  daughter  of  the  late 
Ben  Brown,  of  Pittsburgh,  Penna.,  is  now 
playing  one  of  the  leading  roles  in  the 
musical  "Lend  an  Ear."  We  remember 
Shirley  as  a  very  talented  youngster,  and 
we  predict  a  bright  future  for  her  in 
the  entertainment  world. 

•  Pay  increases  of  $4.50  per  week  for 
exchange  workers  negotiated  with  eight 
distributors  earlier  this  year  have  now 
been  extended  to  all  companies  signing 
blanket  exchange  contracts  with  the  IA. 
Signing  of  contracts  with  Eagle-Lion 
completed  agreements  with  the  four  re- 
maining unsigned  companies — United 
Artists  Monogram  and  National  Screen 
Service. 

•  As  titular  head  of  LLPE  (Labor's 
League  for  Political  Education)  for  the 
International  Alliance,  Dick  Walsh  colla- 
borated with  the  New  York  State  10th 
District  in  sponsoring  a  luncheon  last 
month  in  honor  of  former  governor  Her- 
bert H.  Lehman,  candidate  for  U.  S. 
Senator,  and  Mayor  Wm.  O'Dwyer,  of 
N.  Y.  City,  Democratic  nominees  (both 
elected,  incidentally).  The  luncheon  was 
attended  by  hundreds  of  representatives 
of  theatrical  labor  unions  in  the-  State. 

To  Tom  Murtha,  president  of  the  10th 
District,  who  was  in  charge  of  arrange- 
ments for  the  luncheon,  the  affair  had  a 
special  significance,  for  in  his  early  days 
he  and  Mayor  O'Dwyer  were  members  of 
the  N.  Y.  City  police  force  and  worked 
the  same  beat. 

•  Cecil  R.  Wood,  Sr.,  member  of  Local 
306  and  president  of  the  25-30  Club,  of 
N.  Y.  City,  was  honored  recently  by  his 
employers,  Pathe  France,  Inc.,  at  a  sur- 
prise breakfast  party  in  commemoration 
of  his  50th  anniversary  as  a  projection- 
ist. Cecil's  energy  and  enthusiasm  belie 
his  76  years. 

•  We  were  glad  to  hear  that  our  good 
friend,  Ralph  Kautzky,  Altec  Service  in- 
spector for  the  Broadway  (N.  Y.  City) 
area  for  many  years,  has  been  promoted 
to  the  post  of  New  York  suburban  field 
manager,  covering  New  Jersey  and  up- 
state New  York.  Kautzky  was  extremely 
popular  with  the  boys  along  Broadway, 
and  he  has  their  best  wishes  in  his  new 
job. 

•  A  new  exhibitor  outfit  opened  a  drive- 
in  theatre  in  Kingsville,  Texas  (Corpus 
Christi  604  jurisdiction)  with  non-union 
projectionists.  Several  attempts  to  arrive 
at  a  working  agreement  with  the  exhibit- 


Wm.   P.  Covert 


ors  failing,  the  Local  established  a  picket 
line.  Five  weeks  of  intensive  picketing 
did  the  trick,  and  contracts  were  signed 
with  the  Local.  D.  A.  Brandon,  business 
representative,  and  Chester  Kyle  nego- 
tiated for  Local  604. 

•  When  Bill  Covert,  2nd  vice-president 
of  the  IA,  and  business  representative  for 
Local  173,  Toronto,  Canada,  returned 
from  the  ILO  (International  Labor  Or- 
ganization) conference 
in  Geneva,  Switzer- 
land, which  he  attended 

>  [  as  a  technical  labor  ad- 
[  viser,  he  praised  the 
aims  and  purposes  of 
this  body.  With  dele- 
gates from  65  countries 
participating  in  the 
sessions,  this  32nd  in- 
ternational conference 
considered  such  topics 
as,  for  example,  inter- 
national minimum 
standards,  industrial  relations,  vocational 
guidance,  employment  agencies,  migra- 
tion for  employment,  wages,  working  and 
living  conditions,  and  other  matters  re- 
lating to  social-labor  legislation. 

"If  the  ILO  is  to  achieve  its  objective 
and  to  maintain  its  pre-eminent  position 
in  the  field  of  international  labor  rela- 
tions and  be  a  guide  to  social  and  eco- 
nomic progress,"  said  Covert,  "it  must 
adapt  itself  to  the  age  in  which  it  has  its 
being;  for  the  best  legislation  is  but  a 
temporary  expedient  that  a  later  and 
wiser  age  will  efface.  It  cannot  and  must 
not  stand  still — and  governments  must 
also  be  prepared  to  change  their  policies 
in  an  ever-changing  world,  if  they  hope 
to  progress." 

Bill  is  very  proud,  and  justly  so,  of 
his  part  in  this  step  toward  a  world 
brotherhood  of   man. 

•  Recent  out-of-lown  visitors  to  the  office 
of  IP:  Frank  (Bud)  Long,  Jr.,  St.  Louis 
Local  143;  Dennis  F.  Harrington,  Sara- 
toga Springs  Local  592;  William  (Bill) 
Hartnett,  Ottawa  Local  257;  David  H. 
Koskoff,  Los  Angeles  Local  150;  F.  A. 
Hindemith,  Port  Jervis,  N.  Y.  Local  353, 
and  Wm.  F.  Brobacker,  Middletown, 
N.  Y.,  Local  311. 

•  The  officials  of  Local  486,  Hartford, 
Conn.,  were  commended  by  local  news- 
papers for  their  splendid  cooperation  in 
the  recent  Hartford  Community  Chest 
drive.  Through  the  efforts  of  Donald 
McDonnell  and  Charlie  North,  secretary 
and  business  representative,  respectively, 
free  motion  pictures  were  shown  for  three 
hours  every  night  during  the  campaign. 

•  Six  months  of  negotiations  by  Local 
159  with  the  Jones  Enterprise  Theatres 

(Continued  on  page  29) 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


19 


'Dancing  Shoes'  Sequence  in  'Barkleys' 
a  Marvel  of  Cinema  Technique 


EVER  since  the  release  by  Metro-Gold- 
wyn-Mayer  of  the  "Barkleys  of 
Broadway,"  Fred  Astaire-Ginger  Rogers 
starrer,  IP,  no  less  than  its  readers,  has 
been  ruminating  on  the  means  employed 
to  achieve  the  "dancing  shoes"  sequence 
therein.  Not  since  "Topper"  intrigued 
audiences  a  decade  ago  with  startling 
photographic  magic  has  a  cinematic 
effect  so  fascinated  moviegoers  as  •  did 
this  "Barkley"  job. 

IP  is  indebted  to  the  American  Cine- 
matographer*  for  the  appended  descrip- 
tion of  the  technical  processes  involved 
in  producing  the  startling  "Barkleys" 
photography. 

In  this  sequence  Astaire  portrays  a 
cobbler  whose  shop  is  frequented  by 
theatrical  folk.  A  dancer  brings  him  a 
pair  of  dancing  shoes  to  have  the  taps 
adjusted,  and  before  leaving  executes 
some  nifty  steps  before  the  awe-struck 
Astaire.  When  the  shoes,  with  nobody 
in  them,  suddenly  do  a  few  tap  steps, 
Astaire  looks  at  them  in  amazement,  then 
decides  to  try  them  on.  The  shoes  all 
but  "carry  him  away."  As  they  go 
through  lightning  steps,  Astaire's  body 
tries  desperately  to  keep  up  with  them. 

12  Shoes  Alone  Dance  Rhythmically 

Suddenly,  other  dancing  shoes  magic- 
ally appear  on  the  counter,  tapping  to 
the  music.  Then  six  pairs  tumble  down 
from  the  shelves  back  of  the  counter  and 
execute  a  routine  around  the  startled 
Astaire,  who,  still  wearing  the  dancing 
shoes,  joins  in,  culminating  one  of  the 
most  effective  dance  numbers  ever  staged. 

Astaire  dreamed  up  the  idea  for  the 
sequence,  planned  it  out  on  paper,  then 
took  it  to  Irving  Ries,  M-G-M's  wizard 
of  optical  printing.  From  here  on  it  was 
Ries'  baby,  and  what  he  did  with  it 
proves  conclusively  that  his  well  of  cine- 
matic wizardry  is  far  from  dry  despite 
his  25  years  of  concocting  optical  leger- 
demain at  M-G-M. 

Together  with  Ries,  Astaire  worked 
out  the  dance  routines,  then  tests  were 
shot  in  black-and-white.  When  the 
routine  was  perfected,  and  the  action  was 
carefully  plotted  to  jibe  with  the  require- 
ments of  optical  printing,  they  went  on 
the  set  and  photographed  the  routines  in 
Technicolor.  The  action  was  carefully 
cued  to  a  playback  of  music  and  taps. 

Blackout  of  Dancers'  Forms 

When  a  satisfactory  take  of  the  basic 
scene  was  completed,  the  set  was  cleared 
of  players,  then  completely  draped  in 
black  velvet.  The  "invisible"  tap  dancers 
— six  in  all — were  then  photographed  as 

*  September,  1949,  issue:  "The  Dancing  Shoes," 
p.  318. 


Clip  from  "Barkleys".  Shoes  tumble  from  shelf 
and  dance  around  Astaire.  Shoes,  which  were 
superimposed,  were  first  photographed  on 
dancers  masked  in  black  against  a  black  back- 
ground, after  which  they  were  printed  in  by  the 
travelling-matte  process. 

they  went  through  their  dance  routine 
over  in  front  of  the  black  backdrop. 
The  dancers  were  dressed  in  black  tights 
and  shirts,  their  hands  covered  with 
black  gloves  and  their  faces  similarly 
obscured  with  black  masking.  Only  their 
white  shoes  were  visible. 

Guide  marks  placed  on  the  velvet 
covering  the  floor  served  as  a  guide  for 
the  dancers,  so  their  movements  would 
be  kept  in  proper  relation  with  that  of 
Fred  Astaire  when  the  two  takes  were 
superimposed.  A  pair  of  ballet  slippers 
also  enter  the  scene  momentarily  on  in- 
visible dancing  feet,  and  this  required 
still  a  third  take,  which  was  likewise 
superimposed — a  matter  that  required 
careful  and  exact  timing. 

As  if  the  problem  of  superimposing 
six  pairs  of  dancing  shoes — actually 
dancing,  that  is — were  not  enough  to 
toss  in  the  lap  of  Ries  for  one  produc- 
tion, Astaire  also  thought  it  would  be  a 
good  idea  to  have  the  shoes  jump  from 
the  shelves  back  of  the  counter  onto  the 
shop  floor,  at  the  beginning  of  the  dance. 
Shoes,  especially  with  feet  in  them,  just 
don't  fit  in  narrow  shelves,  and  besides 
the  black-masked  dancers  would  have  to 
stand  upright  in  order  to  execute  the 
jump. 

Ries  solved  this  problem  by  having 
the  top  row  of  shelves  cut  off  for  this 
take.  This  enabled  the  dancers  to  stand 
on  the  next  row  of  shelves,  begin  the 
routine  with  a  few  tap  steps,  jump  to 
the  floor  and  continue  tapping.  The  top 
section  of  shelving  was  later  replaced 
for  the  balance  of  the  sequence. 

Shoe  Visibility;  Multiple  Prints 

The  big  problem  encountered  by  Ries 
was  that  of  keeping  each  dancing  shoe 
visible  in  its  entirety  at  all  times,  except 
when  it  passed  momentarily  behind  Fred 
Astaire  dancing  in  the  middle  of  the 
floor.     Normally,    when    a    dancer's    leg 


crossed  between  camera  and  the  shoe  on 
the  opposite  foot,  that  shoe  would  be 
obscured  from  the  view  of  the  camera. 
In  order  to  make  the  illusion  of  the 
shoes  dancing  alone  seem  real,  it  became 
necessary  to  "fill  out,"  or  complete,  the 
image  of  those  shoes  thus  obscured  in 
the  original  negative. 

Ries  solved  the  problem  by  employing 
simple  animated  cartoon  technique.  He 
first  projected  frame  by  frame  on  anima- 
tion celluloids,  or  "cells,"  that  portion 
of  the  negative  showing  the  obscured 
shoes.  An  artist  outlined  the  missing 
portions  of  the  shoes  on  the  cell,  later 
inked  them  in,  and  Ries  photographed 
it.  The  result  was  superimposed  in  the 
printing. 

As  the  picture  was  being  photographed 
in  Technicolor,  this  meant  that  the  cells 
had  to  be  photographed  three  times — 
once  for  each  of  the  three  color  negatives 
that  comprise  the  Technicolor  system. 
Subsequently,  these  negatives  were  com- 
bined with  the  first  to  produce  the  com- 
plete image.  "From  there  on,"  said 
Ries,  "it  was  just  a  matter  of  routine 
matte  printing." 

Travelling  Matte  Process 

Although  "routine"  to  Ries,  the  tech- 
nique of  travelling  matte  printing  still 
is  something  of  a  mystery  even  to  many 
professional  moviemakers,  and  woull 
require  more  space  than  is  available 
here  to  explain  it  fully.  But  roughly,  it 
consists  of  superimposing  a  figure  (or 
figures)  in  a  scene  when  printing  the 
film,  rather  than  by  double  exposure,  as 
in  early  days  of  cinema  trickery.  The 
travelling  matte,  which  is  made  photo- 
graphically, consists  of  a  strip  of  clear 
film  with  the  area  corresponding  to  that 
of  the  figure  to  be  printed  in  being  fully 
opaque.  This,  when  combined  with  the 
negative,  leaves  unexposed  on  each  frame 
of  the  film  the  area  that  will  be  occupied 
by  the  figure  to  be  superimposed  in  a 
subsequent  printing  step. 

In  the  case  of  the  "dancing  shoes,"  a 
matte  was  made  to  blank  out  the  area 
on  each  frame  representing  the  shoes. 
This  allowed  the  shoes  subsequently  to 
be  printed-in,  a  step  which,  because  of 
carefully  controlled  exposure  and  print- 
ing light,  made  the  shoes  appear  as 
though  they  were  photographed  simul- 
taneously with  Fred  Astaire. 

"The  dancing  shoes  sequence,"  said 
Ries,  "required  two  months  to  conceive 
and  execute.  We  shot  all  the  action  on 
stage  in  three  days.  The  rest  of  the  time 
was  spent  in  making  the  mattes,  doing 
the  animation  work  and,  finally,  the 
printing." 


PROJECTIONISTS' 

QQ  SERVICE 


$3 


MANUAL 


20 


INTERNATIONAL  PROJECTIONIST 


November  1949 


•  LOOKING  BACK-TO  THE   FUTURE* 


While  reviewing  a  book  recently  we  suddenly  became 
-aware  of  how  easily  one  can  forget  information  of  a 
fundamental  nature  as  one  progresses  to  more  ad- 
vanced equipment  and  technique.  This  train  of  thought 
-was  responsible   for  this,  we  think,  aptly-headed   de- 


partment which,  to  be  a  regular  feature  of  IP,  will 
cover  a  variety  of  topics  and  will  serve  the  dual  purpose 
of  providing  basic  information  to  the  younger  crafts- 
men and  as  a  review  for  those  of  long  service. 

Fittingly  enough,  this  department's  inaugural  presen- 
tation is  an  excerpt  from  the  aforementioned  book.f 


REFLECTION  is  the  means  by  which 
most  things  are  made  visible  to  our 
eyes.  This  page  is  made  visible  be- 
cause light  from  the  sun,  or  more  prob- 
ably from  an  artificial  lamp,  is  reflected 
from  this  page  to  your  eye.  Many  light 
rays  are  reflected  this  way  at  any  one 
time,  and  your  eye  sees  the  sum  total 
■of  all  of  these  rays.  Paper  is,  however, 
not  the  best  reflector:  in  fact,  it  is  com- 
paratively poor  in  that  respect.  The  ideal 
device  is  the  mirror,  which  is  specially 
■constructed  for  that  purpose. 

Although  in  any  case  of  reflection  there 
are  always  many  light  rays  involved,  it 
is  convenient  for  our  purpose  to  trace 
the  action  of  one  single  ray  at  a  time. 
A  plane  surface  is  one  which  is  entirely 
flat,  such  as  a  pane  of  glass. 

In  Fig.  1  the  plane  surface  may  be 
assumed  to  be  a  smooth  highly  polished 
piece  of  metal.  The  light  ray  issuing  from 
point  P  falls  upon  the  reflecting  surface 
and  is  turned  back  from  the  surface  at 
the  same  angle  at  which  it  arrived. 

To  explain  this  condition,  an  imaginary 
line  is  drawn  at  right  angles  to  the  re- 
flecting surface  at  the  point  0  where  the 
arriving  light  ray  meets  the  surface.  This 
imaginary  line,  AOB,  is  known  as  the 
normal  and  is  always  perpendicular  to 
the  reflecting  surface.  Use  of  the  normal 


Pi       Pz     Pi      P4      P5 


FIG.    1.    A   single   light   ray   reflected    from 
plane  surface.    The   angle   of   incidence   (i) 
equal  to  the  angle  of  refractions  (r). 


t"Tv  Projection  and  Picture  Enlarge- 
ment," by  Allen  Lytel;  published  by  John 
F.  Rider,  Publisher,  New  York.  See  review 
on  page  30. 


FIG.   2.    Regular   reflection   occurs   when    light 

strikes   a    plane   surface.    In    this   case   all    the 

incident  angles   are  equal  to  each  other. 

line  in  the  illustrations  concerned  with 
the  action  of  light  will  serve  as  a  handy 
reference;  however,  it  must  be  remem- 
bered that  it  is  drawn  only  for  reference 
and  that  it  does  not  really  exist. 

In  accordance  with  the  laws  of  physics, 
the  angle  that  the  incident,  or  arriving, 


Pi    Ps    P4    Ps 


FIG.  3.  Irregular,  or  diffuse,  reflection  occurs 
when  light  .strikes  an  uneven  surface.  The 
angles  of  incidence  are  different  from  each 
other,  although  each  incident  angle  is  equal 
to  its  own  angle  of  reflection. 

light  ray  makes  with  the  normal  is  equal 
to  the  angle  which  the  reflected,  or  de- 
parting, light  ray  makes  with  the  same 
normal.  In  other  words.  POA  is  equal  to 
AOQ,  or  the  angle  of  incidence,  i,  is 
equal  to  the  angle  of  reflection,  r. 

If  the  angle  between  light  ray  PO  and 
the  normal  AOB  is  45  degrees,  then  the 
angle  between  light  ray  OQ  and  the  nor- 
mal will  be  45  degrees.  If  the  incident 


light  ray  were  along  the  normal  line 
AOB,  the  reflected  ray  would  follow  the 
same  path  back  from  the  reflecting 
surface. 

There  are,  however,  many  different 
qualities  of  reflection,  some  materials 
being  better  reflectors  than  others.  An 
example  will  help  make  this  clearer. 

Regular  reflection,  illustrated  in  Fig. 
2,  occurs  when  light  strikes  a  mirror 
or  other  smooth  flat  shiny  objects  and 
the  rays  are  reflected  in  a  uniform  man- 
ner. Automobile  windshields  may  reflect 
a  great  deal  of  light  from  the  sun  when 
the  angle  is  right  and  this  light  may  be 
reflected  into  another  driver's  eyes,  caus- 
ing a  safety  hazard.  An  ordinary  piece 
of  plain  glass  may  act  as  a  mirror  if  not 
viewed  directly  head-on. 

Irregular  or  diffused  reflection,  shown 
in  Fig.  3,  occurs  when  light  strikes  un- 
even surfaces,  and  since  all  the  light  rays 
travel  in  different  directions  after  being 
reflected,  there  is  not  a  great  quantity 
of  light  in  any  given  direction.  Thus  it 
is  impossible  to  reflect  any  useful  amount 
of  light  from  a  blotter  or  rug  or  any 
similarly  rough  surface — most  certainly 
not  the  glare  which  may  be  produced  by 
reflecting  light  from  an  automobile  wind- 
shield  or  even    a   water   tumbler. 

The  mirror,  shown  in  Fig.  4,  is  front- 
surfaced,    such   as   is    used    in    cameras, 

FIG.   4.     In   a   front-surfaced    mirror,   reflection 

is   from   the    front   surface   of   the    glass.   The 

apparent   source   of   the   image    is    behind   the 

back    surface    of    the    glass. 


I ,  /REFLECTION 
U/,0F  LIGHT 
lARAY  2 


\ !  '     APPARENT  SOURCE  OF 
*  ,    THE  REFLECTED  LIGHT 
P1     RAYS 


INTERNATIONAL  FROJECTIONIST 


November  1949 


21 


FIG.  5.    The  virtual  image  A'B'  appears  to  be 
in  back  of  the  mirror.    It  is  the  same  size  as 
the  object,  and  vertically  erect,  although   re- 
versed horizontally. 

optical  systems,  and  projection  tele- 
vision. As  may  be  seen,  the  light  is  re- 
flected from  the  front  surface  of  the  glass, 
and  since  the  light  does  not  pass  through 
the  glass  at  all,  there  is  no  loss  in  bril- 
liance. This  type  of  mirror  is  used  wher- 
ever it  is  important  that  the  greatest 
possible  image  brilliance  be  obtained,  as 
in  TV  projection. 

Because  the  front  surface  is  made  re- 
flecting, the  front  silver-like  coating  may 
be  scratched  or  damaged  very  easily; 
hence  mirrors  of  this  type  should  never 
be  cleaned  unless  absolutely  necessary, 
and  then  only  with  absorbent  cotton 
dipped  in  clean  water.  Even  fingerprints 
can  destroy  this  front-surfaced  mirror 
because  the  reflecting  coating, is  excep- 
tionally thin.  The  mirrors  should  always 
be  handled  with  extreme  care  and  no 
fingermarks  should  ever  be  left  on  the 
surface.  These  mirrors  should  always  be 
handled  by  the  edges  or  back  where 
possible. 

Referring  to  Fig.  4,  point  P  is  a  source 
of  light,  or  an  object  which  reflects  light, 
and  its  image  is  to  be  formed  in  the  mir- 
ror. Many  light  rays  leave  it,  some  of 
which  strike  the  mirror  and  create  the 
image  which  is  the  reflection  of  the  ob- 
ject. Although  the  action  of  only  two  rays 
is  shown  in  Fig.  4,  it  is  understandable 
that  a  similar  action  will  take  place  for 
all  of  the  rays  which  impinge  upon  the 
mirror.  Light  rays  1  and  2  issuing  from 
point  P  will  be  considered  in  the  analysis. 

Path  of  the  Light  Rays 

Normal  1  is  a  perpendicular  dropped 
from  P  to  the  surface  of  the  mirror ;  nor- 
mal 2  is  drawn  perpendicular  to  the  re- 
flecting surface  where  light  ray  1  strikes 
the  mirror,  and  normal  3  is  the  same 
where  light  ray  2  strikes  the  surface. 
Being  a  flat  surface,  regular  reflection 
takes  place,  the  reflected  rays  being 
1'  and  2'. 

Now,  if  we  forget  for  the  moment  that 
rays  1'  and  2'  are  reflected  and  consider 
them  as  simply  issuing  from  the  mirror, 
there  must  be  a  point  of  origin  for  these 
rays.  This  point  may  be  determined  by 
extending  these  reflected  rays  with  imag- 
inary  lines   through   the   mirror. 


This  is  done  in  Fig.  4  with  the  dashed 
lines.  They  meet  at  P'  and  this  is  the 
apparent  source  of  the  reflected  light 
rays  1'  and  2'.  These  rays  seem  to  come 
from  behind  the  mirror,  and  this  point 
P'  is  as  far  in  back  of  the  reflecting  sur- 
face as  the  original  source  P  is  in  front 
of  the  surface.  The  point  P'  is  known  as 
the  virtual  image  point. 

Image  Dimension,  Orientation 

Referring  again  to  the  incident  and 
reflected  waves,  the  angles  r  and  i  for 
rays  1  and  1'  and  2  and  2'  are  equal  in 
accordance  with  the  basic  laws  of  reflec- 
tion as  previously  stated.  Two  very  sig- 
nificant conditions  associated  with  reflec- 
tions from  such  plane  mirrors  must  be 


»i 


FIG.  6.  In  a  rear-surfaced  plane  mirror,  the 
incident  ray  bends  at  the  front  surface  of  the 
glass  as  it  enters  the  glass.  Reflection  is 
from  the  rear  surface,  although  the  image 
seems  to  come  from   behind  the  mirror. 

mentioned.  These  are  the  dimension  and 
orientation  of  the  image  which  takes 
place  during  the  reflection  process. 

Let  us  examine  another  example  of 
such  reflection,  this  time  considering  the 
dimensional  relationship  between  the  real 
image  and  the  virtual  image.  This  is 
shown  in  Fig.  5.  The  object  being  re- 
flected is  the  arrow  AB.  Two  rays  are 
shown  issuing  from  points  A  and  B.  These 
are  reflected  by  two  pairs  of  rays  to  the 
eye,  as  shown.  Since  images  in  a  plane 
mirror  seem  to  come  from  in  back  of  the 
mirror,  we  can  determine  the  apparent 
source  of  these  reflected  rays  by  extend- 
ing them  back  through  the  mirror.  This 
operation  develops  the  virtual  image 
A'B'.  Now  if  we  measure  the  dimensions 
of  the  real  image  AB  and  the  virtual 
image  A'B',  we  note  that  the  two  are  of 
like  size.  In  other  words,  reflection  in 
plane  mirrors  neither  magnifies  nor  re- 
duces the  image  dimension.  This  is  a 
very  important  point  in  connection  with 
the  means  for  accomplishing  magnifica- 
tion of  the  image. 

Another  point  of  importance  associated 
with  reflections  in  plane  mirrors  is  the 
relative   orientation  of  the  reflection.  As 


VIRTUAL- 
IMAGE  OF 
THE  CATH-. 
ODE  RAY 
TUBE 
PICTURE. 


PLANE 
-MIRROR 
a.' 


fillr -. 


y    1\12 

3Nr^-!L 

aTwb 

/cathode  ray 
tube  picture 

FIG.    7.     Diagrammatic    representation    of    re- 
flections in  a  television  receiver  where  a  plane 
mirror  is  used  for  viewing. 

the  consequence  of  the  action  of  reflec- 
tion in  plane  mirrors,  which  gives  an. 
image  behind  the  mirror,  the  orientation 
of  the  reflection  is  reversed  (with  respect 
to  the  object,  not  the  observer)  along, 
the  horizontal  plane:  that  which  is  right 
in  the  object  appears  to  the  left  in  the 
reflected  image,  and  vice-versa. 

Vertically  the  image  is  erect,  that  is,. 
the  top  and  bottom  portions  of  the  re- 
flected image  are  in  the  same  relation 
to  each  other  as  the  object,  but  not  so 
the  left  and  right  portions  of  the  image 
with  respect  to  the  object.*  This,  too, 
(Continued,  foot  of  next  page) 

*  That  is,  the  reflection  of  a  right-hand  glove,  fingers- 
pointing  up,  would  look  like  a  left-hand  glove* 
fingers    pointing    up. 


FIG.  8.    Changing  the  tilt  of  the  plane  mirror 

changes    the    position    of   the    image    and    the 

proper   viewing    angle. 


22 


INTERNATIONAL  PROJECTIONIST 


November  1949 


Proposed  American  35-mm  Film  Perforation  Standard 


THE  proposed  American  Standard  for 
a  common  type  35-mm  film  perfora- 
tion for  both  positive  and  negative  film, 
•which  is  illustrated  here,  has  been  pro- 
mulgated by  the  Society  of  Motion  Pic- 
ture Engineers  for  a  90-day  trial  and 
criticism.  It  is  now  being  proposed  to 
the  American  Standards  Association  for 
adoption  in  order  to  solve  the  registra- 
tion problems  that  exist  in  the  printing 
of  certain  types  of  color  release  prints. 

It  is  possible  to  meet  the  problems  of 
exact  registration  needed  for  color  prints 
by  the  use  of  cine  negative  perforations 
in  the  release  prints.  However,  many 
people  are  reluctant  to  do  this  because 
they  fear  that  they  cannot  in  this  way 
make  release  prints  which  will  have  satis- 
factory projection  lives.  [Note:  See 
"Safety  Film:  Projection  Factors,"  in 
IP  for  November  1948,  p.  9,  for  examples 
of  color  film  perforations. — Ed.] 

One  answer  to  this  problem  is  the  use 
of  combination  positive  and  negative  per- 
forations as  shown  here  in  the  proposed 
new  standard.  While  the  problem  of 
preparing     satisfactory     color      release 


prints  is  the  reason  for  the  presentation 
of  this  proposal,  the  whole  question  of 
35-mm  standards  is  involved. 

The  problem  is  an  old  one,  dating 
back  to  1916,  and  those  especially  in- 
terested in  the  matter  may  obtain  biblio- 
graphical data  thereon  through  the 
SMPE. 

Standards  Appendix 

The  dimensions  given  in  this  standard  rep- 
resent the  practice  of  film  manufacturers  in 
that  the  dimensions  and  tolerances  are  for 
film  immediately  after  perforation.  The 
punches  and  dies  themselves  are  made  to 
tolerances  considerably  smaller  than  those 
given,  but  owing  to  the  fact  that  film  is  a 
plastic  material,  the  dimensions  of  the  slit 
and  perforated  film  never  agree  exactly  with 
the  dimensions  of  the  punches  and  dies. 

Shrinkage  of  the  film,  due  to  change  in 
moisture  content  or  loss  of  residual  solvents, 
invariably  results  in  a  change  in  these  di- 
mensions during  the  life  of  the  film.  This 
change  is  generally  uniform  throughout  the 
roll. 

The  uniformity  of  perforation  is  one  of 
the  most  important  of  the  variables  affecting 


FIGURE  1 

Proposed    American    Standard 
Cutting  and  Perforating  Dimensions  for 

35-Millimeter  Motion    Picture 

Combination   Positive-Negative  Raw  Stock 


LOOKING  BACKWARD  .  .  . 

is  an  important  point  because  it  is  taken 
into   account    in   TV   reflection    systems. 

Reflection  from  a  Rear-Surfaced 
Plane  Mirror 

The  ordinary  mirrors  used  in  homes 
are  made  of  plate  glass,  with  the  reflect- 
ing surface  located  at  the  rear  of  the 
glass.  Light  must  travel  through  the 
glass,  and  out  again  as  in  Fig.  6.  Mirrors 
of  this  type  actually  do  not  present  as 
clear  an  image  as  the  front-surfaced  mir- 
ror because  some  light  is  absorbed  during 
its  passage  through  the  glass.  Although 
the  light  has  to  pass  through  the  glass 
twice — once  on  its  way  in  and  once  on 
its  way  out — the  amount  of  light  reflected 
is  usually  sufficient  for  all  practical 
purposes. 

Another  difference  in  the  process  of 
reflection  taking  place  in  rear-surfaced 
mirrors  with  respect  to  front-surfaced 
mirrors  is  refraction.  The  light  rays 
which  pass  through  the  glass  are  slightly 
bent  as  shown  in  Fig.  6.  This  causes  a 
certain  amount  of  distortion,  which  is  not 
noticeable  in  the  average  plane  mirror 
employed  in  the  home,  but  it  does  become 
a  major  factor  in  precision  optical  instru- 
ments. The  amount  of  refraction  shown 
in  Fig.  6  is  far  in  excess  of  that  normally 
encountered  and  is  used  solely  for  illus- 
trative purposes. 

Use  of  Plane  Mirrors  in  Tv 

The  combined  action  of  reflection  and 
image  reversing  in  a  plane   mirror  has 


(Continued  from  preceding  page) 

been  and  still  is  in  use  in  Tv  receivers. 
Prior  to  the  war,  RCA,  GE,  and  several 
other  manufacturers  produced  Tv  receiv- 
ers wherein  a  hinged  mirror,  tilted  at  a 
45°  angle  and  located  above  the  cathode- 
ray  picture  tube,  afforded  a  reflected 
image  of  the  picture  on  the  cathode-ray 
tube  screen.  The  process  of  reflection  is 
shown  diagrammatically  in  Fig.  7. 

In  order  to  compensate  for  the  revers- 
ing action  which  takes  place  during  re- 
flection, the  orientation  of  the  picture  on 
the  cathode-ray  tube  must  be  such  as  to 
make  the  picture  appear  correct  when 
viewed  in  the  mirror.  This  is  accomp- 
plished  by  electrically  reversing  the  pic- 
ture on  the  tube  screen  and  utilizing  the 
reversing  action  during  reflection  to  make 
the  picture  normal. 

For  the  purpose  of  discussion,  assume 
for  the  moment  that  the  face  of  the  cath- 
ode-ray picture  tube  is  flat,  instead  of 
slightly  convex.  As  we  saw  in  Figs.  4  and 
5,  and  the  text  describing  them,  there  is 
an  apparent  vertical  image  of  the  tube 
face  whose  position  depends  upon  the 
positions  of  the  mirror  and  the  tube. 
Fig.  7  shows  the  location  of  the  virtual 
image  with  the  mirror  at  45°. 

Figure  8  shows  the  change  in  angle  of 
the  reflected  center  line  ray  as  the  mirror 
is  tilted  either  side  of  45°.  In  use  the 
image  of  the  tube  face  is  tilted  slightly 
backward,  indicating  that  the  mirror  is 
raised  to  slightly  more  than  45°. 


steadiness  of  projection.  Variations  in  pitch 
from  roll  to  roll  are  of  little  significance 
compared  to  variations  from  one  sprocket 
hole  to  the  next.  Actually,  it  is  the  maxi- 
mum variation  from  one  sprocket  hole  to 
the  next  within  any  small  group  that  is 
important. 

Preliminary  Work  Dates  Back  to   1932 

Perforations  of  this  size  and  shape  were 
first  described  in  the  Journal  of  the  SMPE 
in  1932  by  Dubray  and  Howell.  In  1937  a 
subcommittee  report  reviewed  the  work  to 
date.  The  main  interest  in  the  perforation 
at  that  time  was  in  its  use  as  a  universal 
perforation  for  both  positive  and  negative 
film. 

The  perforation  has  been  adopted  as  a 
standard  at  this  time  largely  because  it  has 
a  projection  life  comparable  to  that  of  the 
perforation  used  for  ordinary  cine  positive 
film,  and  the  same  over-all  dimensions  as 
the  perforations  used  in  the  negative  film. 

FIGURE  2 

Dimensional  data  relative  to  Fig.  1. 


Key 

Inches 

Mm. 

A 

1.377    ±0.001 

34.98    ±  0.025 

B 

0.1870  ±0.0005 

4.750  ±0.013 

C 

0.1 100  ±  0.0004 

2.794  ±  0.01 

D 

0.073    ±0.0004 

1.85    ±0.01 

E 

0.079    ±  0.002 

2.01     ±  0.05 

G 

Not    >  0.001 

Not    >  0.025 

1 

0.999    ±  0.002 

25.37    ±0.05 

L* 

18.70      ±0.015 

474.98    ±0.38 

R 

0.013    ±0.001 

0.33    ±0.03 

These  dimensions  and  tolerances  apply  to  the 
material  immediately  after  cutting  and  perforating. 

*  This  dimension  represents  the  length  of  any  100 
consecutive  perforation  intervals. 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


23 


YOUR  Monthly  Chat  in  the  July  last 
issue  (we  are  a  long  way  down 
in  the  blue  Pacific)  was  extremely 
interesting.  After  reading  the  many  dis- 
cussions in  IP,  I  was  wondering  when 
American  equipment  manufacturers 
were  going  to  stumble  onto  the  simple 
solution  of  their  big  headache  of  an  ef- 
fective means  for  cooling  the  aperture 
area  of  the  projector  regardless  of  the 
ampere  load  of  the  arc. 

The  aforementioned  column  lists  in 
order  four  possible  solutions  of  this 
problem:  Glass  Filters,  Carbon  Jaw 
Water-Cooling,  Air-Cooled  Aperture,  and 
Water-Cooled  Aperture.  Why  leave  the 
most  important  and  obviously  simple 
solution  to  the  last? 

Like  so  many  of  our  modern  (?) 
ideas,  water-cooling  of  the  projector  gate 
is  an  old  dodge.  To  the  best  of  my 
knowledge,  German  engineers  first  em- 
ployed this  tactic  in  1933-34,  and  during 
the  latter  year  introduced  what  was  to 
my  mind  one  of  the  finest  projector 
mechanisms  ever  produced — the  Erne- 
mann  V  "cold"  projector.  Here  is  the 
statement  made  by  Ernemann  engineers 
in  1934: 

"The  criterion  of  projector  quality  is  no 
longer  confined  ...  to  smooth  running, 
absence  of  travel-ghost  and  steadiness  of  the 
projected  image.  These  qualities  are  taken 
for  granted.  The  test  now  relates  to  the 
manner  in  which  the  effects  of  heat  upon 
the  film  and  other  vulnerable  components 
are  met. 

"In  order  to  bring  out  the  full  artistic 
potentialities  of  the  film,  persistent  endeav- 
ors have  resulted  in  the  use  of  more  and 
more  powerful  arc  lamps.  The  consequent 
greater  intensity  of  the  accompanying  heat 
has  a  deleterious  effect  upon  the  sharpness 
of  the  picture  image  and  the  quality  of  the 
sound  reproduction.  In  these  days  prefer- 
ence should  rightly  be  given  to  a  projector 
in  which  the  effects  of  heat  are  reduced  to 
a  minimum." 

Air-  Plus  Water-Cooling 

The  following  observations  by  Erne- 
mann engineers  would  seem  to  bear  di- 
rectly upon  the  recent  contribution  to 
the  literature  by  F.  J.  Kolb,1  of  Eastman 
Kodak  Co.,  which  has  had  frequent  men- 
tion in  discussions  of  this  problem  of 
cooling  picture  equipment. 

"The  Ernemann  II  projector  (1925-26) 
has  blower  tubes  incorporated  in  it,  and 
all  succeeding  Ernemann  mechanisms  are 
equipped  with  built-in,  air-cooling  attach- 
ments whereby  air  is  blown  against  the  film 
from  either  side.  The  air-cooling  system 
ensures  effective  cooling  of  the  film  within 
the  film  gate. 

"In  consequence,  however,  of  the  great 
intensification  of  the  illumination  of  the 
picture,  a  new  source  of  trouble  has  arisen 

]  "Air-Cooling  of  Motion  Picture  Film  for 
Higher  Screen  Illumination,"  presented  at  the 
Spring,  1949  Convention  of  the  Society  of  Mo- 
tion   Picture    Engineers. 


VI  E  WS 

from  the 

ANTIPODES 


Exemplifying  the  adage  that  we  need  not 
so  much  to  he  told  as  to  he  reminded  are 
these  forthright  observations  by  one  who 
obviously  has  had  long  and  varied  expe- 
rience in  the  craft — and  a  good  memory. 


By  DOUGLAS  McMURRAY 

Sydney,  Australia 


by  reason  of  the  heat  communicated  by 
radiation  to  the  film  track. 

"In  contrast  to  air,  water  is  endowed 
with  extraordinary  capacity  for  taking  up 
heat.  Cooling  by  a  stream  of  water  is  ac- 
cordingly the  appropriate  expedient  for 
carrying  away  the  heat  from  the  film  track 
.  .  .  and  for  maintaining  that  general  area 
at  a  low  temperature  irrespective  of  the 
working  ampere  load.  Cooling  by  this 
method  obviates  the  formation  of  film  de- 
posits as  well  as  .  .  .  bulging  or  'reaching' 
of  the  film. 

"The  joint  effect  of  water-  and  air-cooling 
establishes  model  conditions  for  the  travel 
of  the  film  through  the  projector.  .  .  .  The 
growing  popularity  of  color  film  demands 
a  further  intensification  of  the  light  and  a 
greater  tendency  to  heating.*  It  follows 
that  the  water-cooling  system  is  bound  to 
gain  in  significance." 

Easy  Adaptability  Cited 

This,  bear  in  mind,  is  what  the  Erne- 
mann engineers  thought  as  far  back  as 
1934!  The  entire  system  is  simplicity 
itself  and  could  be  easily  adapted  to 
any    projector.    Instead   of   a   solid    gate 

*  Relative  to  this  point  is  the  following  inter- 
esting excerpt  from  the  aforementioned  paper  by 
F.    J.    Kolb: 

"Additional  evidence  for  believing  that  only  the 
image  absorbes  energy  is  given  by  the  behavior 
cf  dye-image  films  which  are  relatively  trans- 
parent in  the  near  infra-red,  even  for  relatively 
high  absorption  and  density  in  the  visible  region. 
Such  dye-image  films  show  less  heating  and  less 
of  the  thermal  effects  than  silver-image  film  when 
projected  at  the  same  intensity.  We  have  found 
this  advantage  to  be  roughly  proportional  to 
their    transparency    in    the    infra-red." 


casting,  the  Ernemann  gate  was  made 
with  hollow  chambers.  Water  was  at- 
tached to  an  input  tube,  and  the  continu- 
ous overflow  fed  back  through  another 
tube  to  a  tank  or  a  drain. 

With  water  circulating  through  the 
gate,  it  is  impossible  for  a  projector  to 
get  any  warmer  than  the  palm  of  a  pro- 
jectionist's hand.  It  matters  not  whether 
the  lamp  is  pulling  50  or  250  amperes,. 
the  film  will  not  be  adversely  effected 
by  heat  to  any  degree. 

I  note  in  IP  a  report  that  Century 
jector  Corp.,  is  now  equipped  with  a 
water-cooled  jacket.  Century  is  at  last 
on  the  right  track,  but  it  can  go  even 
farther  to  its  own  advantage  by  rede- 
signing the  gate  itself.  If  American  de- 
signers were  to  adapt  the  Ernemann  idea 
of  water-cooling  to  their  projectors,  they 
could  lick  this  heat  problem  overnight. 
The  writer  would  wager  that  if  this  were 
done  there  would  be  a  ton  of  glass  heat 
filters  going  cheaply. 

It  is  interesting  to  note  that  the  British 
regard  the  Ernemann  V  projector  so> 
highly  that  they  are  now  making  almost 
an  exact  copy  of  it  in  the  form  of  the 
Walturdaw  V. 

I  gather  that  there  are  no  Ernemanns- 
in  use  in  America.  [Note:  Not  in  the 
U.S.A.,  but  there  are  a  few  operating  in 
Canada,  and  numerous  such  units  in 
Central  and  South  America. — Ed.]  The 
reason  for  this  is  probably  the  open 
design,  which  American  projectionists 
regard  as  a  bit  strange  and,  perhaps,  a 
big  fire  risk.  This  really  is  not  true, 
however,  and  I  only  wish  that  the  boys 
in  the  States  could  see  and  operate  this 
mechanism. 

Ernemann  Design  Details 

I  do  not  wish  for  one  minute  to  decry 
American  projectors,  which  have  proved 
their  worth  throughout  the  world;  but 
I  sincerely  believe  that  much  could  be 
learned  from  a  careful  study  of  the  basic 
Ernemann  design.  Brenkert  would  seem 
to  have  profited  by  such  study,  since 
all  Ernemann  models  from  the  II  on 
were  automatically  lubricated. 

As  far  back  as  15  years  ago  the  Erne- 
mann V  was  a  water-  and  air-cooled 
projector.  The  gate  was  of  the  long  de- 
sign, with  all  tension  easily  adjustable 
while  running.  The  gate  has  a  remov- 
able aperture  plate  which  could  be  fitted 
with  velvet  ribbon  runners  to  render 
unnecessary  the  waxing  of  new  prints. 

Inside  the  projector  was  a  mercury 
switch  which  was  connected  to  a  trip 
immediately  above  the  top  feed  sprocket. 
If  the  film  ever  parted  in  the  gate,  the 
top  loop  would  build  up,  release  the 
trip  lever,  and  the  mercury  switch  would 
then  cut  off  the  projector  motor  and  the 
exciter  lamp.  The  same  switch  could 
also  be  used  to  drop  all  port  shutters 
at  the  same  time.   The  Zeiss  Ikon  system 


24 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


kept  all  ports  open  by  means  of  electro- 
magnetic devices. 

Notable  Progress  in  Optics 

The  standard  lens  jacket  on  the  Erne- 
mann  V  was  made  to  take  Zeiss  lenses 
of  from  3^2  to  4-inch  aperture  having  a 
speed  of  F:1.9  —  which  speed  is  pre- 
cisely what  the  "experts"  are  now  urging 
projectionists  to  use  in  order  to  combat 
faulty  light  distribution  on  the  screen. 

I  have  not  had  the  opportunity  to  see 
any  coated  projection  lenses  from  the 
German  companies,  but  the  British  know 
that  the  Germans  have  been  very  active 
in  this  field.  They  are  unable  to  get 
any  definite  information  regarding  Ger- 
man research  because  the  Zeiss  factories 
(where  the  Ernemann  projectors  were 
manufactured)  are  in  the  Russian-occu- 
pied zone  and  are  therefore  cut  off  from 
the  rest  of  the  world. 

German  engineers  are  credited  with 
having  made  the  statement  recently  that 
if  they  could  scrap  all  their  present 
machine  tools  and  patterns  and  start  all 
over  from  scratch,  they  would  make  a 
projector  the  like  of  which  the  world 
has  never  seen.  Bragging?  Perhaps; 
but  it  would  be  foolhardy  to  sell  them 
short  in  view  of  their  prior  fine  achieve- 
ments in  this  field. 


NEWS    PROJECTIONS 

Jottings  of  happenings  which,  while  mostly  ot 

a  non-technical  nature,  have  a  bearing  upon 

general  industry  welfare  and  progress. 

EASTERN  labs  have  upped  their 
prices  by  8  per  cent,  with  the  ad- 
vance being  caused,  it  is  said,  by  the 
recent  liy2  per  cent  wage  hike  won 
by  IA  lab  workers  Local  702.  .  .  .  Nov. 
17  ended  the  30-day  grace  period  for 
the  filing  with  the  U.  S.  District  Court 
in  New  York  of  final  proposals  for 
splitup  of  Loew,  Warner  and  20th-Fox 
theatre  holdings.  .  .  .  All  major  com- 
panies now  shuttling  their  top  stars 
around  the  country  as  an  aid  to  better 
biz.  .  .  .  Paramount  has  won  two  addi- 
tional years  in  which  to  divest  itself 
of  holdings  in  the  Michigan  Butterfield 
circuit.  .  .  .  Only  13  per  cent  of  those 
queried  in  a  recent  survey  by  Wood- 
bury College  students  are  willing  to 
pay  a  ''nominal"  sum  for  Tv  programs. 

J.  Arthur  Rank,  British  film  tycoon, 
discloses  he  lost  $9,380,000  in  film  pro- 
duction during  the  year  ended  last 
June  25.  This  figure  would  have  been 
about  30  percent  higher  in  dollars  be- 
fore the  recent  develuation  of  the 
British  pound.  The  almost  confiscatory 
nature  of  the  British  entertainment  tax 
is  reflected  by  Rank's  statement  that 
"we  have  paid  out  of  our  theatres, 
entertainment  tax  which  exceeds  our 
loss  by  $2,800,000.   .   .   .  American  ex- 


sm»i:ir  s\mpi  jti: 


SEALED 

LENS  ELEMENTS 


,  ONE-PIECE 
MOUNT 


ANODIZED 
FINISH 


.COATED 
'  OPTICS 


*s 


IF  THE  SPEED  OF  THE  LAMP  IS  SLOWER  THAN  THE  LENS, 

WHY  USE  A  FAST  LENS? 

This  is  answered  in  detail  in  an  article  by  Dr. 
J.  L.  Maulbetsch  in  the  "International  Projec- 
tionist" of  September.  1947.  In  brief,  a  fast  lens 
gives  more  uniform  illumination  because  hav- 
ing larger  lens  elements  it  picks  up  more  of  the 
edge  illumination  than  a  slower  lens  with  corre- 
spondingly smaller  lens  elements. 

ARE  ADAPTERS  NECESSARY  FOR  SNAPLITE  LENSES? 

Fittings  are  available  to  adapt,  where  neces- 
sary, Snaplite  lenses  to  all  currently  manufac- 
tured professional  projectors. 

WHERE    CAN    DRAWINGS    OF    THESE    ADAPTERS    BE 

OBTAINED? 

The  required  adapters  are  shown  on  the  last 
page  of  Kollmorgen  bulletins  204  and  206. 
These  bulletins  are  available  at  your  theatre 
supply  dealers.  Dimensions  of  all  adapters  ex- 
cept the  shade  tube  are  fixed.  The  length  of  this 
shade  tube  varies  with  the  focal  length  of  the 
lens. 

HOW  MANY  LENS  ELEMENTS  ARE  THERE  IN  A  SUPER- 

SNAPLITE? 

Six — two  pairs  of  elements  are  cemented  to- 
gether and  two  elements  are  single. 

ARE  THE  CEMENTED  SURFACES 
COATED? 

No — treating  cemented  surfaces  with 
an  anti-reflection  coating  would  not  in- 
crease the  light  transmission  of  the 
lens. 

"You  Get  the  Most   Uniform   Light  with   Super-Snaplite" 

koij,aioin;Cy    ,      #x 

y^afca/  corporation 


2  Franklin  Avenue 
Brooklyn  11,  New  York 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


25 


hibitor  organizations  are  getting  defi- 
nite commitments  from  Congressman 
for  a  sharp  reduction  in  the  admission 
tax.  .  .  .  Fifty  good-sized  theatres 
equipped  for  Tv  and  interconnected 
could  make  possible  the  programming 
of  exclusive  Tv  programs,  says  N.  L. 
Halpern,  Tv  consultant  for  Fabian 
Theatres.  .  .  .  Canadian  theatres  in 
1948  took  in  a  record  gross  of  $69,619,- 
047,  which  is  $6,753,768  more  than  in 
1947.  .  .  .  Potentialities  of  advertiser- 
sponsored  features,  offered  to  exhibit- 
ors without  charge,  and  to  be  played  at 
minimum  admission  prices,  are  being 
explored. 


Competition   has   been   eliminated   in 
the  Detroit  area  by  theatre  groups  who 


have  operated  collusively  and  dictate 
terms  on  a  take-it-or-leave-it  basis,  said 
indie  producer  Sam  Goldwyn.  .  .  .  Mo- 
tion picture  stocks  are  regaining  their 
former  position  as  sound  investments, 
says  the  Wall  Street  Journal.  .  .  A.  F. 
of  M.  scale  for  members  working  in 
Tv  films  revealed  as  $27  per  man  for 
each  film  program  of  15  minutes  or 
less.  .  .  .  More  than  8000  U.  S.  theatres 
have  played  reissues  during  the  past 
year.  .  .  .  Du  Mont  asserts  it  is  per- 
fecting a  system  of  non-flicker  color 
Tv  which  will  "employ  principles  used 
in  the  continuous  motion  picture  pro- 
jector." (Ala  the  old  Mechau  rotating 
wheel  with  36  individual  lenses?).  .  .  . 
Paramount  expected  to  acquire  total 
ownership  of  Wilby-Kincey  Circuit  by 
year's  end.  .  .  .  More  than  20  regional 


TYPE  "HI"  TRANSVERTER 

t^/fyv,  *  DELUXE  THEATRES 
yl^C/*  SMALLER  THEATRES 
*/  J*  DRIVE-IN  THEATRES 

*  AUDITORIUMS 


PLUS  FEATURES 


5  TYPES 


TYPE  "IV"   /or  Simplex  High  I  KW 
Arcs 


TYPE  "HI"    /or  Suprex  Type  Arcs 

TYPE  "HIH"  /or  Suprex and Spot  Arcs 

TYPE  "MA"  /or  50-70  Volt  Low  and 
High  Intensity  Arcs 

TYPE  "CP"   /or  60-75  Volt  High  In- 
tensity Arcs 


1.  Velvet- smooth  power — no 
A.  C.  ripple 
2.  Cool,  quiet  performance 
3.  Safe,  slow  operating  speed 

4.  Economical,  long-life,  trouble- 
free  operation 
5.  Modernized,  compact,  hori- 
zontal design 
6.  Proved  experience  since  1906 
7.  Sealed-for-life  ball  bearings 
8.  Designed  for  specific   power 
supply  of  each  installation 
9.  Easily  adjusted  ballast  rheostats 


Distributed  by 

NATIONAL  THEATRE  SUPPLY 

In  Canada:  GENERAL  THEATRE  SUPPLY  COMPANY 


MOTORS    • 


r   THE  HERTNER  ELECTRIC  COMPANY 

12690  ELMWOOD  AVE.  •  CLEVELAND  11,  OHIO 

A  General  Precision  Equipment  Corporation  Subsidiary 
MOTOR-GENERATORS    •    GENERATOR    SETS 


exhibitor  outfits  have  readied  petitions 
to  FCC  for  theatre  Tv  channels. 


Believe  it  or  not,  RCA  has  added 
playground  equipment  to  its  drive-in 
theatre  line.  (Shades  of  popcorn,  etc.). 
.  .  .  Latest  Canadian  theatre  figures 
list  326  houses  open,  110  under  way, 
and  142  planned.  .  .  .  General  Precision 
Equipment  Corp.  (parent  company  of 
numerous  motion  picture  manufactur- 
ing units)  reports  $88,367  net  profit, 
equal  to  15  cents  per  common  share, 
for  three  months  ending  Sept.  30  last. 


Bausch  &  Lomb's  97th  Year 

Ninety-six  years  ago  last  Nov.  2  a  small 
optical  shop  opened  its  doors  in  Rochester, 
N.  Y.,  offering  for  sale  a  few  thermometers, 
field  glasses,  magnifiers  and  horn-rimmed 
spectacles.  Today  the  Company  founded  by 
John  J.  Bausch  and  financed  by  the  $60  life- 
savings  of  a  friend,  Capt.  Henry  Lomb,  is 
the  world's  leading  producer  of  scientific 
optical   instruments. 

During  the  Civil  War,  with  Captain  Lomb 
sending  home  his  Army  pay  to  keep  the 
company  going,  Bausch  built  and  installed 
the  first  power  lens  grinding  machine  in 
America.  A  short  while  later  he  literally 
stumbled  upon  the  use  of  vulcanized  rubber 
foi  eyeglass  frames  when  he  found  a  chunk 
of  the  hard,  black  material  on  the  street. 
Before  the  war  ended,  the  cookstove  in  the 
Bausch  kitchen  was  converted  into  one  of  the 
first  plastics  "laboratories"  in  the  U.  S. 

In  1915,  William  Bausch,  younger  son  of 
the  founder,  climaxed  several  tedious  years 
of  glass-making  experiments  by  producing 
the  first  pure  melt  of  optical  glass  ever  made 
in  America.  By  the  time  the  U.  S.  entered 
World  War  I,  B.  &  L.  became  the  sole  source 
of  supply,  not  only  of  optical  glass,  but  of 
gunfire  control  instruments  as  well. 

Since  then,  scores  of  new  products  have 
been  added,  and  two  additional  plants  opened 
at  Wellsville,  N.  Y.,  and  at  Midland,  Canada. 
Among  the  many  new  items  are  phase  con- 


CURRENT  DISC  RECORDINC  CUTS 
78  rpm 

96  grooves  per  Inch 


45  rpm 

264  grooves  per  Inch 


33%  rpm 

224  grooves  per  Inch 


Audio  Devices,  Inc.,  New  York. 
Unretouched  shadowgraphs,  showing  Audiodiscs 
recorded   at  78,  45,  and   33 1/3   rpm.    These 
representations  magnified  125  times. 


26 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


trast  microscopes;  a  tiny,  plastic  gonioscope 
for  diagnosing  glaucoma,  one  of  the  principal 
causes  of  blindness;  tension-type  eyeglass 
frames,  a  series  of  wide-field  microscopes 
and  home  movie  lenses  that  rival  the  B.  &  L. 
Baltar  lenses  used  by  Hollywood  cameramen, 
a  television  slide  projector,  and  an  ultra- 
violet microscope  for  cancer  research.  A 
vibration-proof  underground  laboratory  for 
making  diffraction  gratings  for  spectrogra- 
phic  analysis  was  also  completed. 


New  F:1.3  Balowstar  16-mm  Lens 

The  new  F:1.3  Cine  Balowstar  lens  has 
had  its  first  demonstration  in  N.  Y.  City. 
Designed  and  executed  by  Dr.  F.  G.  Back, 
creator  of  the  internationally  famous  "Zoo- 
mar"  lens,  the  Balowstar  is  said  to  do  for 
motion  pictures  what  the  image  orthicon  does 
for  video — transmits  color  perfectly  under  a 
minimum  of  lighting.  Everything  visible  to 
the  naked  eye — even  the  flicker  of  firelight — 
can  be  captured  on  film. 

This  so-called  "Night-Hawk"  of  lenses, 
with  its  aperture  range  of  from  F:1.3  to  16, 
focuses  from  infinity  down  to  4  feet.  It  is 
adaptable   to   any  16-mm   camera. 


New  Kodak  Mexico  City  Plant 

Kodak  Mexicana,  Ltd.  has  opened  its 
new  quarters,  embracing  35,000  square 
feet,  in  Mexico  City  and  is  operating 
as  the  latest  link  of  the  modernization 
program  now  underway  by  Kodak  to  pro- 
vide more  complete  decentralized  service 
in  key  geographical  centers. 

PERSONNEL 

James  Frank,  Jr.  has  been  named  vice- 
president  in  charge  of  sales  for  Theatre 
Control  Corp.,  Detroit  company  which  is 
marketing  nationally  the  Ticograph  device 
which  automatically  audits  motion  picture 
theatre  admissions.  Frank,  formerly  with 
RCA  and  with  National  Theatre  Supply  Co., 
is  a  governor  of  the  SMPE. 

Ralph  M.  Evans,  superintendent  of  East- 
man Kodak  Co.'s  color  control  department, 
received  the  Samuel  Warner  Award  of  the 
SMPE  at  the  latter  organization's  recent  66th 
convention  in  Hollywood.  The  award  is  pre- 
sented annually  for  outstanding  work  in  the 
motion  picture  field. 

Dr.  E.  M.  Honan,  one  of  America's  rec- 
ognized authorities  on  the  development  of 
sound  in  the  motion  picture  field,  who  until 
his  retirement  on  Sept.  30  last  was  engineer- 
ing manager  of  the  Erpi  division  of  Western 
Electric  Co.,  has  joined  the  Altec  Compa- 
nies as  engineering  manager.  He  will  head- 
quarter  in   Hollywood. 

R.  E.  Warn,  has  been  named  manager  of 
the  newly-formed  Hollywood  division  of 
Westrex  Corp.,  which  on  Oct.  1  took  over 
the  motion  picture  activities  of  the  Erpi  divi- 
sion of  Western  Electric.    Warn,  associated 


with  the  industry  since  1928  when  he  joined 
Erpi,  has  served  that  company  in  Dallas, 
Kansas  City,  New  York  and  Washington. 
Managing  director  of  Western  Electric  Co. 
of  Australia,  Warn  was  brought  back  in 
1948  to  become  chief  engineer   of  Westrex. 


Color  Photography  More  Simple, 
Says  Kodak  Labs  Director 

The  complexity  of  three-color  photog- 
raphy for  the  user  has  decreased  greatly 
in  the  past  20  years,  according  to  Dr. 
Cyril  J.  Staud,  director  of  Kodak  Re- 
search   Laboratories.    "While    it    is    not 


possible  to  make  three-color  photographs 
with  the  simplicity  of  black-and-white 
pictures,"  said  Dr.  Staud,  "definite  prog- 
ress has  been  made  in  making  available 
a  wide  variety  of  materials  and  processes 
to  fill  the  many  desires  for  color  photo- 
graphs for  a  multitude  of  purposes." 

The  Kodak  laboratory  head  said  that 
so  far  all  methods  used  to  produce  "wide 
hue-range"  in  color  photographs,  either 
as  transparencies  or  prints,  revolve  about 
the  use  of  three  colors.  He  recalled  that 
in  1861  Clerk  Maxwell  showed  that  a 
photograph  in  color  could  be  produced 
through  the  use  of  three  black-and-white 


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Produces  a  steady,  sharp,  uniformly 
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Silvered  glass  reflector  and  two- 
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system. 

Draws  only  10  amperes  from  any 
110-volt  A.C.  convenience  outlet. 
Adjustable,  self- regulating  trans- 
former, an  integral  part  of  the  base, 
makes  the  use  of  heavy  rotating 
equipment  unnecessary. 


Easily  operated.  Automatic  arc 
control  maintains  constant  arc  gap, 
free  from  hiss  or  flicker.  A  trim 
of  carbons  burns  one  hour  and  20 
minutes  at  21  volts  and  45  amperes. 

Horizontal  masking  control.  Can 
be  angled  at  45  degrees  in  each 
direction.  Color  boomerang  con- 
tains six  slides  and  ultraviolet  filter 
holder. 

Mounted  on  casters.  Easily  dis- 
assembled for  shipping. 


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NAME 


14  CITY  PARK  AVE. 
TOLEDO  2,  OHIO 


THEATRE. 


STREET. 


CITY  &  STATE 


INTERNATIONAL  PROJECTIONIST 


November  1949 


27 


positives  placed  in  separate  projection 
lanterns.  In  front  of  each  lantern  was  a 
solution  containing  a  colored  liquid  cor- 
responding to  the  color  filter  through 
which  the  photographic  material  had 
originally   been    exposed. 

This  system,  Dr.  Staud  said,  was  a  good 
example  of  an  "additive"  process.  It  has 
been  developed  to  yield  results  of  very 
high  quality.  But  additive  color  proc- 
esses have  always  presented  serious  tech- 
nical problems  from  the  standpoint  of 
wide  use,  he  added. 

Subtractive  Process  Simpler 

Dr.  Staud  said  that  '"subtractive"  color 
processes,  however,  have  relative  simplic- 
ity from  the  standpoint  of  the  user.  In 
the  subtractive  system,  a  color  print  made 
by  any  of  the  current  processes  starts 
with  a  white  area,  and  subtractive  colors 
are  used.  In  this  system,  white  light  from 
which  blue  has  been  taken  yields  yellow. 
White  from  which  green  has  been  taken 
gives  magenta.  When  red  light  is  removed 
from  white  light,  it  gives  a  blue-green 
called   "cyan." 

Because  of  their  relative  simplicity,  Dr. 
Staud  said,  the  subtractive  processes 
"have  expanded  the  color  photographic 
horizon  to  include  literally  millions  of 
people. 

"This  does  not  mean  that  subtractive 


uso 


color  photography  is  not  complex.  And, 
as  far  as  I  can  see,  no  color  processes 
will  equal  black-and-white  photography 
in  its  simplicity  of  materials  or  processes. 
But  the  use  of  the  materials  in  still  and 
motion  picture  cameras  now  has  the  ease 
of  black-and-white  photography.  Further- 
more, because  of  their  nature,  color  pho- 
tographs are  viewed  much  more  critically 
than  their  black-and-white  counterparts." 

Dr.  Staud  also  discussed  a  form  of 
subtractive  photography  known  as  "im- 
bibition color  photography."  This  de- 
pends upon  the  formation  of  a  gelatin 
relief  image  which  can  be  dyed  and  from 
which  dye  can  be  transferred  to  another 
layer  when  the  two  are  brought  into 
contact. 

He  traced  color   development  then  to 


the  "one-shot  camera"  and  three  separate 
negatives  from  one  exposure,  to  Techni- 
color three-color  negatives,  and  to  a  new 
"multilayer  stripping  film"  recently  de- 
veloped by  Kodak. 

Multilayer  Stripping  Film 

This  multilayer  film  is  an  experimental 
material  which  can  be  used  in  a  standard 
motion  picture  camera  and  will  yield 
three  color-separation  negatives.  After 
exposure  in  the  camera,  the  top,  or  blue- 
sensitive,  layer  is  stripped  off  onto  a 
piece  of  clear  film  support,  carrying  with 
it  the  yellow  filter  layer.  After  this  has 
been  done,  the  middle  layer  is  stripped 
off  onto  a  second  piece  of  clear  film 
support.  The  red-sensitive  layer  remains 
on  the  original  film.  The  three  films 
resulting  from  this  stripping  operation 
are  then  processed  to  yield  three  color- 
separation  negatives. 

Dr.  Staud  also  discussed  color  coupler 
photography,  in  which  certain  types  of 
developer  solutions  combine  with  other 
compounds  called  couplers  to  produce 
dyes.  Color-coupler  processes,  he  said, 
have  greatly  extended  the  range  and  use 
of  color  photography  today.  He  gave 
details  of  modern  color  processes  devel- 
oped by  several  companies  in  this  coun- 
try and  abroad,  all  of  which  are  coupler 
processes. 


In  Hollywood . .  .In  Your  Theater 

It's  Bausch  &  Lomb  for 

Top  Image  Quality 


•  For  many  years,  the  world's  leading  camera- 
men in  the  big  name  studios  of  Hollywood  have 
preferred  Bausch  &  Lomb  lenses  for  top  image 
quality.  They  depend,  too,  on  Bausch  &  Lomb 
lenses  for  projecting  process  backgrounds. 
Your  decision  to  use  Bausch  &  Lomb  Super  Cine- 
phor  lenses  for  top  image  quality  .  .  .  maximum 
edge -to -edge  brilliance,  contrast  and  sharpness 
on  your  screen  .  .  .  has  the  overwhelming  support 
of  the   motion  picture   industry.   Bausch  &  Lomb 
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23 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


IN  THE  SPOTLIGHT 

(Continued  from  page  19) 

in  Portland,  Ore.,  resulted  in  new  con- 
tracts calling  for  pay  increases  retro- 
active to  April  first  last.  Despite  many 
obstacles,  Steve  Hazlewood,  secretary, 
and  Z.  A.  Sax,  business  representative, 
stuck  to  their  guns  and  refused  to  call  it 
quits  until  the  contracts  were  signed, 
sealed,  and  delivered. 

•  We  were  quite  taken  back  several 
weeks  ago  when  we  learned  of  the  am- 
bitions of  James  Petrillo,  head  of  the 
AF  of  M  (American  Federation  of  Musi- 
cians) to  include  in  his  organization  all 
film  editors  in  the  television  field.  Pet- 
rillo's  claim  to  jurisdiction  over  film  edi- 
tors in  the  tele  field  is  being  hotly  con- 
tested by  John  Lehners,  business  repres- 
entative of  IA  Film  Editors  Local  776, 
on  the  ground  that  all  film  editing,  irre- 
spective of  its  character,  falls  within  the 
IA's  jurisdiction.  It  seems  to  us  that 
Petrillo's  eyes  perhaps  are  getting  too 
big  for  his  stomach.  We.  shall  see  what 
we  shall  see. 

•  Harry  Storin  and  Jack  Winick,  New 
York  City  Local  306,  represented  the 
Projectionists'  Square  Club  at  the  recent 


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National  Convention  held  in  Atlanta,  Ga. 
Jake  Pries,  Local  225  business  represen- 
tative, was  host  to  the  boys  during  their 
visit  to  Atlanta. 

•  Newly-elected  officers  for  Film  Post 
No.  1292,  N.  Y.  City,  are  Tony  Rugino, 
commander;  Sam  Wittenberg  1st  vice- 
commander;  Albert  Sprung  2nd  vice- 
commander;  Joe  Greece  3rd  vice-com- 
mander; Frank  Miller  adjutant;  Edgar 
Heidelberg  finance  officer  and  Archie 
Hollander  hospitalization.  All  IA  veter- 
ans are  eligible  for  membership  in  Post 
1292. 

THE  35-MM  PROJECTION 
POSITIVE  FILM 

(Continued  from  page  9) 

in  the  camera  reproduces  light  values 
positively   instead    of   negatively. 

Now,  Reversal  Negative  developed  in 
the  ordinary  way  comes  out  as  ordinary 
negative,  and  ordinary  negative  and  posi- 
tive films  come  out  as  reversal  films  when 
given  reversal  processing.  But  in  this,  as 
in  other  photographic  matters,  the  best 
results  are  obtained  only  by  selecting 
materials  prepared  expressly  for  the  uses 
to  which  they  are  to  be  applied. 

Reversal  Negative  Prints 

Reversal  Negative  is  seldom  used  in 
professional  motion  picture  work,  but  it 
is  very  popular  with  amateur  movie-mak- 
ers because  it  eliminates  the  expense  of 
separate  positive  projection  prints.  How- 
ever, the  use  of  reversal  films  does  not 
permit   a   very   professional   job   of   film 


JOHN  H.  MACLAY— Manager, 
Grand,  Strand  and  Avon  Theatres, 
Dubuque,  Iowa — says: 

"We  have  always  found 
RCA  Service  to  be  emi- 
nently satisfactory." 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


cutting  with  fades,  wipes,  lab-dissolves, 
etc. 

Duplitized  Color  Negative  corresponds 
to  Duplitized  Positive,  but  color  prints 
on  Duplitized  Positive  are  often  made 
from  two  separate  negatives  exposed  in 
a  separation  camera  or  run  face-to-face 
in  "bipack"  in  an  ordinary  camera  fitted 
out  with  double  magazines. 

Monopack  Color  Negative,  the  same 
as  Monopack  Color  Positive,  is  enjoying 
increasing  use.  This  type  of  film  has 
three  emulsion  layers  on  the  same  side 


THIS  IS  WHAT  ^wygfANT! 

Customer  satisfaction— the  theatre 
owner's  #  1  asset.  Create  it  by  using 
CENTURY    PROJECTION    AND    SOUND 

SYSTEMS.  For  the  smallest  to 
the     largest  Drive-in— for  harmony 

of  color  tone  and  picture  brilliance. 


GORDOS   CORPORATION 

86   SHIPMAN   STREET      ■      NEWARK  2,  N.  J. 


INTERNATIONAL  PROJECTIONIST     •      November  1949 


of  the  film.  The  layers  are  dye-treated 
to  respond  to  the  three  color  groups  per- 
ceived by  the  human  eye — scarlet,  green, 
and  indigo.  Upon  reversal  processing 
each  emulsion  layer  is  dye-toned  to  the 
color  complementary  to  that  to  which  it 
has  been  exposed.  Thus: 

(1)  Exposed  to  indigo,  toned  yellow. 

(2)  Exposed  to  green,   toned  magenta. 

(3)  Exposed  to  scarlet,  toned  cyan. 
The  yellow,  magenta,  and  cyan  super- 


SPEER  MAROUSIS  — Owner, 
Regent  Theatre,  New  Castle,  Pa. — 
says: 

"I  have  had  dependable 

RCA  Sound  Service  since 

1928.  I  feel  I  cannot  afford 

to  be  without  it." 

To  get  the  benefits  of  RCA  Service — 

write:    RCA   SERVICE    COMPANY, 

|NC,  Radio  Corporation  of  America, 

Camden,  N.  J. 


posed  images  subtract  from  the  white 
light  of  the  projector  the  proper  amounts 
of  scarlet,  green,  and  indigo  to  form 
upon  the  screen  the  original  scene  in  its 
natural  colors. 

"Direct"  processing  of  Monopack 
Color  Negative  gives  a  negative  of  re- 
versed values:  black  appearing  as  white, 
red  as  green,  blue  as  orange,  etc.  Prints 
in  true  colors  may  be  made  from  the 
negative. 

[To   be  Continued] 


BOOK      REVI  EWS 


Tv  Picture  Projection  and  Enlarge- 
ment, by  Allen  Lytel.  192  pages,  profusely 
illustrated.  John  F.  Rider,  Publisher,  480 
Canal  St.,  New  York.  $3.30. 

Here  is  one  of  those  rare  volumes  that 
are  useful  both  to  the  neophyte  and  the  expe- 
rienced engineer.  At  first  glance  it  appears 
to  be  a  run-of-the-mill  work  on  the  funda- 
mentals of  the  Tv  art,  which  are  appearing 
in  all  too  great  a  profusion  these  days.  As 
one  progresses  through  this  book,  however, 
one's  interest  is  progressively  heightened, 
and  it  is  amazing  to  learn  in  the  process  how 
easy  it  is  to  forget  basic  data  of  this  sort  as 
one  goes  on  to  more  complicated  equipment 
and  technique. 

First  Rate  Job  on  Tv  Optics 

Of  the  six  sections  into  which  the  book 
is  divided,  the  first  two  deal  with  elementary 
optics,  and  it  is  these  chapters  which  should 
exert  the  greatest  appeal  to  one  who  seeks 
to  understand  the  optical  principles  under- 
lying Tv.  The  other  four  chapters  show  how 
these  principles  are  applied  commercially  to 
Tv  equipment  by  the  various  manufacturers, 


Operating  at  85  amperes,  the  Motiograph-Hall  produces  19,000 
lumens — more  light  than  condenser-type  high  intensity  lamps 
operating  at  more  than  twice  this  amperage. 

A  rotating  positive  carbon   (an  exclusive  feature)   permits  even 
burning  of  the  carbons  and  a  proper  crater  form. 
Automatic  focus  control  holds  the  crater  of  the  positive  carbon  at  the  exact  focal  point 
of  the  mirror. 

Th2  carbons  ured  cost  about  one-third  that  of  the  larger  carbons  employed  in  condenser- 
type    lamps   operating   in    the    140-180   ampere   range. 

Other  Mofiograph  products:  1  K.W.  and  46-ampere  high  intensity  arc  lamps,  projectors, 
sound  systems,  motor-generators,  in-car  speaker  equipment  and  junction  boxes,  ramp  switch- 
ing panels  for  drive-ins,   turntables,  etc. 

See  your  Motiograph  dealer  for  a  demonstration  or  write  for  literature. 


in   addition  to   comprehensive  notes  on  the 
adjustment  of  the  various  receivers. 

The  volume  benefits  by  a  good  job  of 
indexing  as  well  as  a  very  useful  bibliog- 
raphy. IP  recommends  this  book  unre- 
servedly. 

Simplified  Stereoscopic  Photography, 
by  C.  W .  Wilman.  Published  by  Marshall 
&  Co.,  Ltd.,  London,  England.   72  pages. 

The  novice  stereoscopist  should  find  this 
book  valuable  in  gaining  concepts  of  the 
fundamental  basis  of  stereoscopic  vision  and 
photography  and  in  applying  them  in  making 
successful  stereoscopic  photographs.  The 
author  shows  that  perception  of  depth  de- 
pends almost  entirely  upon  the  fact  that  near 
and  distant  objects  appear  in  different  rela- 
tive positions  when  seen  by  the  two  eyes  and 
that,  therefore,  satisfactory  stereoscopic  pho- 
tographs can  be  made  by  simply  taking  two 
photographs,  either  simultaneously  or  consec- 
utively, from  two  positions  normally  dis- 
placed 65  mm  horizontally  from  each  other. 

Because  of  the  fact  that  the  camera  lens 


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INTERNATIONAL  PROJECTIONIST     •     November  1949 


inverts  the  image,  the  right-hand  and  left- 
band  image  of  a  stereoscopic  pair  must  be 
transposed   for  proper  viewing. 

Various    Taking    Procedures    Outlined 

The  various  methods  of  taking  stereoscopic 
photographs  include:  (1)  the  single-lens 
method,  in  which  any  ordinary  camera  can 
ibe  used,  the  camera  being  shifted  laterally 
65  mm  between  consecutive  exposures;  (2) 
the  use  of  lens-shifting  devices,  in  which  the 
lens  and  a  suitable  mask  over  the  plate  or 
film  are  shifted  between  consecutive  expo- 
sures; (3)  the  twin-lens  method,  in  which  a 
camera  is  equipped  with  two  lenses,  65  mm 
apart,  with  coupled  shutters,  diaphragms,  and 
focusing  devices,  so  that  two  photographs 
•can  be  taken  simultaneously  on  adjacent  por- 
tions of  a  film  or  plate;  and  (4)  the  use  of 
a  prism  attachment  on  some  single-lens 
cameras,  such  as  the  Leica,  which  permits 
the  taking  of  two  photographs  simultane- 
ously in  the  area  normally  taken  by  one. 

The  necessity  for  great  depth  of  focus  in 
stereos  is  emphasized  and  the  correct  distance 


DICK  LEMUCCHI— Owner,  Tejon 
and  Granada  Theatres,  Bakersfield, 
Calif. — says: 

"For  eighteen  years  RCA  has 
handled  my  service  problems. 
I'm  still  satisfied." 

To  get  the  benefits  of  RCA  Service — 
write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


on  which  to  focus  is  given  as  the  harmonic 
mean  of  the  distances  to  the  near  and  distant 
objects.  A  table  is  given  for  determining  the 
distance  of  nearest  and  farthest  objects  in 
satisfactory  stereos. 

Requisites   for  a  Satisfactory   Viewer 

A  satisfactory  viewer  is  one  which  holds 
the  stereo  pair  with  65  mm  between  centers, 
has  lenses  which  give  a  suitable  magnifica- 
tion of  the  image,  and  has  adjustments  on 
focus  and  on  the  separation  between  the 
lenses  to  accommodate  the  interocular  dis- 
tance of  different  people.  The  advantages  of 
cameras  using  plates,  cut-sheet  film  and  roll 
film  are  discussed.  Any  of  the  usual  pho- 
tographic materials  may  be  used. 

The  author  advises  developing  the  nega- 
tive to  good  contrast  to  avoid  the  appearance 
of  Newton's  rings  in  the  print.  Dirt  and 
scratches  should  be  carefully  avoided.  Vari- 
ous methods  of  transposition  are  described 
and  it  is  emphasized  that  if  transposition  is 
accomplished  by  cutting  either  the  negative 
or  the  positive,  such  defects  as  skewed  hori- 
zons can  be  corrected. 

Chapter  7  deals  with  large-scale  problems 
in  stereoscopy,  such  as  difficulties  in  taking 
exposures  of  near  objects,  reduction  of  sepa- 
ration, rotation  of  a  single-lens  camera 
(about  the  subject  as  center  instead  of  shift- 
ing the  camera  laterally  as  for  normal  stere- 
oscopy), rotation  of  the  subject  (instead  of 
the  camera) ,  rotation  of  twin-lens  cameras, 
mignified  images,  etc. 

Color  films  are  particularly  adapted  to 
stereoscopy  in  that  transparencies  can  be 
viewed  as  readily  as  paper  prints  and  give 
results  superior  to  those  of  paper  prints. 
Suggestions  are  given  regarding  exposure, 
spotting,  and  the  quality  and  type  of  illumi- 
nation for  viewing.  One  chapter  treats  such 
items  as  stereoscopic  line  drawings,  exag- 
gerated relief,  enlargements,  aerial-survey 
work,  stereoscopy  in  astronomy,  the  pseudo- 
scope,  anaglyphs,  and  stereoscopic  projection 
by  polarized  light. — Eastman  Kodak  Co. 
Abstract. 

Elements  of  Sound  Recording,  by  John 
G.  Frayne  and  Halley  Wolfe.  674  pages, 
6  x  9%  inches,  index,  480  illustrations.  John 
Wiley  &  Sons,  New  York.   $8.50. 

This  is  the  best  straightaway  exposition  of 
the  art  of  sound  recording  that  we  have  ever 


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STAR  CORE,  exclusive  feature  with  the 
Lorraine  Carbons  —  a  manufacturing 
process  that  increases  the  performance 
of  the  corbons. 

A  more  brilliant,  steadier,  more  con- 
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seen.  And  well  it  might  be,  because  the 
authors  have  attained  world-wide  recognition 
as  masters  of  this  art,  both  in  their  theo- 
retical approach  and  in  the  practical  applica- 
tion of  the  principles  enunciated  herein. 
The  content  of  this  book  belongs  peculiarly 
to  the  restricted  field  of  sound  recording 
and  reproducing — film,  disc,  and  magnetic 
tape — being  of  an  order  that  is  not  found  in 
books  devoted  to  the  allied  fields  of  elec- 
tronics, radio  engineering,  etc. 

Beginning  with  a  chapter  on  the  nature  of 
sound  and  covering  every  phase  of  recording 
and  reproduction  right  down  to  the  very 
latest  development  in  stereophonic  sound, 
this  book  is  in  itself  a  self-contained  library 
of  the  art  that  covers  every  last  detail  of 
procedure  from  blank  recording  material 
through  the  equipment  used  and  technique 
employed  down  to  the  finished  product. 

Nobody  who  is  seriously  interested  in 
sound  recording  and  reproduction  can  afford 
to  be  without  this  volume.  It  is  absolute 
tops  and  bids  fair  to  maintain  that  position 
for  years  to  come.  It's  a  swell  publishing 
job,  too:  paper,  type,  binding  and,  most 
important,  the  scale  and  clearness  of  the 
illustrations,  contributing  greatly  to  its  over- 
all worth. 


INTfRNATIONAL  PROJECTIONIST     •     November  1949 


31 


THEATRE    TELEVISION  : 
WHAT,  HOW  AND  WHEN 

(Continued  from  page  15) 
transmission  facilities,  or  it  may  be  car- 
ried out  as  a  common  enterprise  by  sev- 
eral theatres  in  a  city  sharing  certain 
facilities  and  co-operating  together. 
Such  a  co-operative  group  is  de- 
scribed hereafter.  Since  the  capital  and 
operating  expenses  of  any  Tv  enterprise 
are  substantial,  it  is  assumed  that  some 
or  all  the  theatres  in  a  city  will  form  a 
co-operative  group,  and  that  this  organi- 
zation will  be  predominant  in  the  theatre 
Tv  industry.  The  present  discussion, 
therefore,  is  limited  to  a  description  of 
theatre  Tv  in  cities  where  it  will  be  pro- 
moted and  carried  on  by  one  or  more 
co-operative  groups. 

Theatre  Tv  envisioning  co-operative 
action  by  several  theatres  in  a  single  city, 
needs  Tv  transmission  facilities  for  five 
purposes: 

Five-Fold  Transmission  Facilities 

1.  For  distribution  of  programs  from  a 
central  distributing  point  to  groups 
of  theatres.  Such  facilities  may  be 
described  as  "Multiple-Addressee  Sys- 
tems." 

2.  For    transmission    of    programs    from 


studios  and  regular  origination  points 
to  the  central  distributing  point.  In 
broadcasting  terminology,  such  fixed 
circuits  are  termed  "Studio-Trans- 
mitter Links." 

3.  For  mobile  remote  pickup  of  pro- 
grams and  transmission  to  the  central 
distributing  point.  In  broadcasting 
terminology,  these  mobile  units  are 
known  as  "remote  pickups"  and  are 
used  for  the  origination  of  programs 
such  as  sports  events,  parades,  news 
events,  and  stage  shows. 

4.  For  transmission  of  programs  to  in- 
tercity relay  points.  These  fixed  cir- 
cuits also  may  be  classified  as  "Stu- 
dio-Transmitter Links." 

5.  For  intercity  relay  of  programs. 

Typical  Theatre  Tv  Hook-up 

The  use  of  transmission  facilities  by 
such  co-operative  groups  is  most  easily 
explained  by  reference  to  Fig.  1,  which 
is  a  diagram  of  a  typical  theatre  Tv 
system  in  two  imaginary  cities,  A  and  B. 
City  A  is  assumed  to  be  located  on  the 
A.T.&T.  coaxial  cable,  and  City  B  is 
assumed  to  be  located  off  the  coaxial 
cable  about  35  miles  east  of  City  A. 
City  A  contains  25  motion  picture  thea- 
tres which  are  part  of  the  co-operative 
Tv  group  and  receive  programs  from  it. 


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FIGURE  1 
Typical  two-city  television  relay  system. 

City  B  contains  15  such  Tv  theatres. 
In  each  city  the  key  point  of  the  sys- 
tem is  the  central  distributing  point 
where  the  multiple-addressee  system  is  lo- 
cated (marked  on  the  diagram  "MAS"). 
The  co-operative  group  in  City  A  main- 
tains studio-transmitter  links  (STL) 
from  one  studio  or  theatre  which  pro- 
duces a  daily  stage  show,  and  from  the 
Municipal  Auditorium.  It  also  utliizes 
two  mobile  remote  pickup  units  which 
are  available  for  use  in  appropriate 
scenes  of  action  throughout  the  area.  It 
contains   a   microwave  relay  transmitter 


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32 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


(M/W  Relay)  which  is  used  to  trans- 
mit programs  to  City  B  on  a  one-way 
circuit.  In  City  A  a  studio-transmitter 
link  (STL)  connects  the  main  distribu- 
tion point  with  the  intercity  relay. 

The  co-operative  group  in  City  B,  run- 
ning a  "barebones"  operation  and  de- 
pending on  City  A  and  the  theatre  net- 
work for  substantially  all  programs,  re- 
quires fewer  transmission  facilities.  It 
must  maintain  a  multiple-addressee  sys- 
tem (MAS)  at  the  central  distributing 
point,  a  microwave  relay  receiver  (M/W 
Relay),  and  a  studio-transmitter  link 
(STL)  to  connect  the  two  points.  It  re- 
quires no  other  transmission  facilities. 

Capital  Costs  of  Installation 

What  investment  will  be  required  to 
install  the  theatre  Tv  systems  described, 
in  the  two  cities?  The  price  of  the  in- 
stallation required  is  approximately  $25,- 
000  per  theatre,  regardless  of  whether 
the  direct-projection  or  the  intermediate- 
film  system  is  used.  The  following  dis- 
cussion endeavors  to  fix  estimated  costs 
of  the  equipment  required  by  the  co- 
operative group  of  City  A. 

1.  Multiple-Addressee  System  —  The 
basic  elements  of  this  system  are  a  trans- 
mitter, associated  control  and  power 
equipment,      film-recording      and      film- 


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camera  equipment,  and  a  multi-beam, 
highly  directional,  antenna  array.  If  live 
programs  are  to  be  produced  locally, 
studio  video  camera  equipment  and  stu- 
dios with  proper  lighting  must  be  pro- 
vided. 

Programs  would  be  beamed  in  the 
necessary  directions  to  permit  reception 
by  each  of  the  theatres  equipped  to  re- 
ceive the  transmissions.  Three  such  di- 
rectional beams  are  pictured  in  Fig.  1 
at  City  A.  In  the  frequencies  involved, 
a  low-power  video  transmitter  would  pro- 
vide satisfactory  signals  to  cover  the  area 
in  which  the  associated  theatres  were 
located. 

While  no  such  multiple-addressee  Tv 
system  is  in  operation  in  this  country, 
the  engineering  principles  underlying  it 
are  not  new,  and  there  is  no  doubt  that 
it  could  be  designed  and  manufactured 
within  a  reasonably  short  period  after 
order. 

With  the  exception  of  the  directive  an- 
tenna, the  other  equipment  would  be 
adapted  readily  from  Tv  broadcast  equip- 
ment now  in  use.  The  directive  antenna 
presents  no  exceptionally  difficult  prob- 
lems, although  it  would  have  to  be  en- 
gineered on  a  custom  basis  to  fit  the 
problems  of  the  particular  city  involved, 
with  the  location  of  theatres  in  view. 

The  capital  cost  of  such  a  system, 
without  studio-camera  equipment  and 
studios,  is  estimated  at  approximately 
$175,000.  This  includes  $25,000  for  the 
acquisition  of  instantaneous  film-record- 
ing equipment,  and  $50,000  as  the  cost 


of  the  directive-antenna  array.  With 
studio-camera  equipment  and  studios, 
about  $100,000  would  be  added  to  the 
cost.  These  estimates  do  not  include  ex- 
penditures for  acquisition  or  remodeling 
of  buildings  or  land. 

2.  Studio-Transmitter  Links  —  The 
necessary  facilities  to  connect  studios  or 
program  origination  points  with  the  cen- 


BOB  LEIBER— Owner,  Paramount 
Theatre,  Braddock,  Pa.  and  Rankin 
Theatre,  Rankin,  Pa. — says: 

"RCA  Sound  and  Service  is 

tops.  It  assures  our  patrons 

of  the  best  performance  at 

all  times." 

To  get  the  benefits  of  RCA  Service — 

write:   RCA  SERVICE    COMPANY, 

INC.,  Radio  Corporation  of  America, 

Camden,  N.  J. 


CLAYTON  BALL-BEARING 

EVEN  TENSION  TAKE-UPS 

For  all  projectors  and  sound  equipments 

All  take-ups  wind  film  on  2,  4  and  5  inch  hub  reels. 
Silent   Chain    Drives 

THE  CLAYTON  REWINDER 

For  perfect  rewinding  on  2000-foot  reels. 

CLAYTON    PRODUCTS    CO. 

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INTERNATIONAL  PROJECTIONIST     •      November  1949 


33 


tral  distributing  point  would  be  substan- 
tially the  same  as  the  equipment  used  by 
Tv  broadcast  stations  to  link  studio  and 
transmitter.  These  connections  may  be 
made  by  microwave  relay,  coaxial  cable, 
or  by  balanced  telephone  wires  over  dis- 
tances from  one  or  two  miles. 

If  studio-transmitter  radio  links  are 
deemed  desirable,  their  cost  would  be 
approximately  $15,000  per  installation. 
If  coaxial  cable  or  television  wires  are 
used,  the  telephone  company  will  pro- 
vide the  service  at  regular  rates,  and 
capital  costs  to  the  theatre  Tv  system 
will   be  nominal. 

3.  Remote  Pickups — The  two  remote 
pickup  units  contemplated  for  City  A 
would  cost  approximately  $50,000  per 
unit.  This  includes  two  portable  camera 
units,  audio  equipment,  a  small  truck, 
and  the  video-link  equipment.  The  audio 
link  is  a  telephone  circuit.  The  video 
relay  may  be  used  over  distances  of 
from  10  to  15  miles,  but  only  over  line- 
of-sight  in  the  high  frequencies  used. 
This  equipment  may  be  owned  and  oper- 
ated, or  may  be  leased  from  the  tele- 
phone company,  or,  perhaps,  from  local 
Tv  broadcast  stations. 

4.  Intercity  Relays — The  one-way  in- 
tercity relay  circuit  from  City  A  to  City 
B,  contemplated  in  Fig.  1,  is  estimated 
to  cost  from  $25,000  to  $50,000.  This 
figure  includes  both  the  transmitting  and 
receiving  units. 

As  described  previously,  the  relay 
transmitter  in  City  A  and  the  relay  re- 
ceiver   in    City    B    would    be    connected 


with  the  central  distributing  point  in 
each  city  by  studio-transmitter  links, 
costing  approximately  $15,000  each.  How- 
ever, given  an  appropriate  location  of 
the.  relay  units,  coaxial-cable  connec- 
tions might  be  provided  by  the  tele- 
phone company. 

On  the  aforementioned  basis,  a  rough 
estimate  of  the  capital  investment  re- 
quired by  the  co-operative  theatre  group 
in  City  A  would  total  approximately 
$445,000,  consisting  of  (1)  multiple- 
addressee  system  and  associated  equip- 
ment including  studio  equipment  $275,- 
000  (2)  three  studio-transmitter  links, 
$45,000  (3)  two  remote  pickup  units, 
$100,000,  and  (4)  50  per  cent  of  the 
cost  of  the  intercity  relay  installation, 
$25,000. 

The  capital  investment  required  in 
City  B  would  be  substantially  less.  The 
cost  of  the  multiple-addressee  system, 
eliminating  $100,000  as  the  cost  of  items 
of  studio  equipment  and  studios  that 
full-scale  program  production  would  re- 
quire, would  come  to  $175,000  or  less. 

If  an  intermediate-film  recording  unit 
were  not  used  in  City  B,  this  cost  would 
be  reduced  by  another  $25,000.  The 
studio-transmitter  link  and  intercity  re- 
lay receiver  installations  would  add  ap- 
proximately $40,000.  Thus,  the  total  in- 
vestment at  City  B  would  approximate 
from  $190,000  to  $215,000. 


[Note:  Subsequent  installments  of  this 
series  will  discuss  transmission  facilities 
for  theatre  Tv,  color  Tv,  and  program- 
ming.— ft/.] 


How  Many? 


Was  this  copy  dog-eared  when  it  came  to  you  ?  How 
many  men  read  it  ahead  of  you? 

You  would  receive  a  clean,  fresh  copy  if  you  had  a 
personal  subscription — and  you  wouldn't  have  to 
wait — you  would  be  first  to  read  it. 

Use  coupon  below. 

INTERNATIONAL    PROJECTIONIST, 
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D  1    year — 12    issues — $2.50 
G  2  years — 24   issues — $4.00 
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Enter  my  subscription  for 


Name 


Address 


City 


State 


STATEMENT  OF  THE  OWNERSHIP, 
MANAGEMENT,  CIRCULATION,  ETC., 
REQUIRED  BY  THE  ACT  OF  CONGRESS 
OF  AUGUST  24,  1912,  AS  AMENDED 
BY  THE  ACTS  OF  MARCH  3,  1933,  AND 
JULY  2,  1946. 

Of  International  Projectionist,  published 
monthly  at  New  York,  N.  Y.,  for  October  1, 
1949. 

State  of  New  York  \ 

County  of  New  York       j    SS- 

Before  me,  a  Notary  Public  in  and  for  the 
State  and  County  aforesaid,  personally  ap- 
peared R.  A.  Entracht,  who,  having  been 
duly  sworn  according  to  law,  deposes  and 
says  that  she  is  the  Business  Manager  of 
International  Projectionist  and  that  the 
following  is,  to  the  best  of  her  knowledge 
and  belief,  a  true  statement  of  the  ownership, 
management  (and  if  a  daily  paper,  the  cir- 
culation, etc.)  of  the  aforesaid  publication 
for  the  date  shown  in  the  above  caption,  re- 
quired by  the  Act  of  August  24,  1912,  as 
amended  by  the  Act  of  March  3,  1933,  em- 
bodied in  section  537,  Postal  Laws  and  Reg- 
ulations printed  on  the  reverse  of  this  form, 
to  wit: 

1.  That  the  names  and  addresses  of  the 
publisher,  editor,  managing  editor,  and  busi- 
ness managers  are: 

Publisher,  International  Projectionist  Pub. 
Co.,  Inc.,  19  West  44  Street,  New  York  18, 
N.  Y. 

Editor,  Henry  B.  Sellwood,  19  West  44 
Street,  New  York  18,  N.  Y. 

Managing  Editor,  R.  A.  Entracht,  19  West 
44  Street,  New  York  18,  N.  Y. 

Business  Manager,  R.  A.  Entracht,  19 
West  44  Street,  New  York  18,  N.  Y. 

2.  That  the  owner  is: 

International  Projectionist  Pub.  Co.,  Inc., 
19  West  44  Street,  New  York  18,  N.  Y. 

R.  A.  Entracht,  19  West  44  Street,  New 
York  18,  N.  Y. 

3.  That  the  known  bondholders,  mort- 
gagees, and  other  security  holders  owning  or 
holding  1  per  cent  or  more  of  total  amount 
of  bonds,  mortgages,  or  other  securities  are: 
None. 

4.  That  the  two  paragraphs  next  above, 
giving  the  names  of  the  owners,  stockholders, 
and  security  holders,  if  any,  contain  not  only 
the  list  of  stockholders  and  security  holders 
as  they  appear  upon  the  books  of  the  com- 
pany but  also,  in  cases  where  the  stockholder 
or  security  holder  appears  upon  the  books 
of  the  company  as  trustee  or  in  any  other 
fiduciary  relation,  the  name  of  the  person 
or  corporation  for  whom  such  trustee  is  act- 
ing, is  given;  also  that  the  said  two  para- 
graphs contain  statements  embracing  affiant's 
full  knowledge  and  belief  as  to  the  circum- 
stances and  conditions  under  which  stock- 
holders and  security  holders  who  do  not 
appear  upon  the  books  of  the  company  as 
trustees,  hold  stock  and  securities  in  a  capac- 
ity other  than  that  of  a  bonafide  owner;  and 
this  affiant  has  no  reason  to  believe  that  any 
other  person,  association,  or  corporation  has 
any  interest  direct  or  indirect  in  the  said 
stock,  bonds,  or  other  securities  than  as  so 
stated  by  her. 

R.  A.  Entracht,  Business  Manager 

Sworn  to  and  subscribed  before  me  this 
26th  day  of  September,  1949. 

(Seal)  BERNARD  SCHWARZ 

Notary  Public,  State  of  New  York,  No. 
31-3559300,  Qual.  in  N.  Y.  Co.,  Cert.  Filed 
with  N.  Y.  Co.  Clerk's  and  Register's,  Term 
expires  March  29,  1951. 


34 


INTERNATIONAL  PROJECTIONIST     •     November  1949 


SO  MUCH 


for  so  LITTLE 


$0.00 


3 


per  copy 
postage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  goinq  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


Sand  goh  ii  Tlowi 


I 


(Do  Tioi  (D&teuf 


INTERNATIONAL  PROJECTIONIST 

19  West  44  Street,  New  York  18.  N.  Y. 

Gentlemen:  Enclosed  find  S3.00  for  a  copy  of  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 
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VOLUME  24       •      NUMBER   12 


30c  A  COPY    •    $2.50  A  YEAR 


«W^tfr-J»<K  mt»  ww  ifajyft* 


Cancer  is  curable  if  discovered  early  and  treated  properly 


If  any  of  these  symptoms  appear,  see  your  doctor  at  once. 

Write  for  the  booklet  about  cancer.  Just  address  your  request  to  "CANCER' 

AMERICAN  CANCER  SOCIETY,  INC. 


©C1B    r2  42<4  8 


tfP 


^ 


'  +  & 


#*& 


International  Alliance  of  Theatrical  Stage 
Employes  and  Moving  Picture  Machine 
Operators  of   the  United    States  and   Canada 


RICHARD  F.  WALSH 

International 
President 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


9  _    .4k  1-irW   Trt    Tft    AAA  DC 


choose 


w 


MAGNARC 

TRADE   MARK    "•" 

1-KW  TO  70  AMPS 

HY-AX"  ARC  MAGNET 


HY-LUMEN"    REFLECTOR 


More  light  at  40  to  70  amperes  than  ever  thought  possible. 
.  .  .  Equals  and  excels  any  reflector  lamp  to  85  amperes,  whether 
they  be  unapproved  water-cooled  or  resurrected  "Hi-Lows".  .  .  . 
Highest  ratio  of  honest  screen  lumens  per  watt  consumed  at  the 
arc.  ...  At  70  amperes,  with  a  projector  having  an  efficient  DISC 
type  revolving  shutter,  it  develops  the  maximum  white  light  that 
can  be  used  without  a  heat  filter  at  no  risk  of  film-heat  damage. 
.  .  .  Operating  costs  under  these  conditions  are  far  below  that  of 
85-ampere  lamps. 

Magnarc  Lamps  assure  80%  side-to-center  (SMPE  Standard) 
screen  light  distribution,  not  a  deceptive  60%  or  "Hot  Center." 
.  .  .  They  are  all  Und.  Lab.,  Inc.  listed.  .  .  .  They  are  not  in- 
surance hazards.  .  .  .  They  are  and  have  been  for  years  "The 
Standard  of  Comparison"  and  "The  First  Choice"  of  large 
and  small  theatres,  drive-ins,  and  the  motion  picture  industry 
in  general! 


FIRST    WITH    THE    FINEST 


i  i 


120-180  AMPERES 


TRADE    MARK   REG. 


NEW     MAGNETIC    STABILIZER 

This  modern  lamp  produces  all  the  light  there  is. 
...  It  is  the  standard  equipment  of  the  nation's  largest 
and  finest  theatres.  .  .  .  Used  by  90%  of  the  largest 
Drive-In  Theatres. 

It  is  the  "Omega"  for  maximum  screen  illumination. 
.  .  .  Nothing  can  even  approach  it  in  white  light  volume 
when  used  with  projectors  that  have  efficient  DISC 
type  revolving  shutters. 

Assures  satisfying  projection  for  Drive-ins  regardless 
of  the  size  of  the  picture,  length  of  throw,  and  under 
all  weather  conditions.  .  .  .  They  are  Und.  Lab.,  Inc 
listed  and,  therefore,  not  insurance  hazards.  .  .  .  Heat 
filter  assures  no  risk  of  film-heat  damage  at  maximum 
arc  amperage. 


1  1 


WHY     EXPERIMENT? 

"J.E.McAULEY  MFG. CD.- 


I  / 


552-554    WEST    ADAMS    STREET 

CHICAGO   6.  ILLINOIS 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


INTERNATIONAL 


ROJ  EC1 


With  Which  Is  Combined  Projection  Engineering 


HENRY  B.  SELLWOOD,  Editor 


Volume  24 


DECEMBER  1949 


Number  12 


Index  and  Monthly  Chat 5 

The   35-mm   Projection   Positive 

Film,   II    7 

Robert  A.  Mitchell 

The  Garutso  'Balanced'  Lens  13 

The  New  Super  13.6-mm  Hitex 
Super   High-Intensity   Carbon     14 

Full  Text  of  California  Supreme 
Court  Decision  on  Local 
Union  Membership  Accept- 
ance,  Rejection    16 

Theater  Television:    What,  How 

and  When   19 

John  Evans  McCoy 

Harry  P.  Warner 
New     4-Inch     Diameter,     Long 

Focal  Length  Lenses   20 

Novel  All-Purpose   Pocket   Film 

Marker     21 

In  the  Spotlight   22 

Harry  Sherman 


French     Propose     21-mm     Film 
Width     24 

Some   Observations   on  the 

Perception  of  Color 25 

News  Projections 25 

Glossary  of  Tv  Terms 26 

George     Eastman:      Father      of 
Modern   Photography    28 

Letters  to  the  Editor   29 

Klondike  Gold  Rush  Days,  Old- 

Time  Movies  Recalled   29 

Otto  Nordling 

The      Origins     of     the     Magic 
Lantern,  III    30 

J.   VOSKUIL 

News  Notes 
Technical  Hints 
Miscellaneous  Items 


Published  Monthly  by 
INTERNATIONAL  PROJECTIONIST   PUBLISHING   CO..    INC. 

19  West  44  Street,  New  York  18,  N.  Y. 

R.  A.  ENTRACHT,  Publisher 
SUBSCRIPTION  REPRESENTATIVES 

AUSTRALIA:  McGills,  183  Elizabeth  St.,  Melbourne 

NEW  ZEALAND:    Te  Aro   Book  Depot,  Ltd.,  64  Courtenay  Place,  Wellington 

ENGLAND  and  DOMINIONS:  Wm.  Dawson  &  Sons,  Ltd.,  Macklin  St.,  London,  W.  C.  2 

Yearly  Subscription:  United  States  and  possessions,  $2.50  (two  years,  $4)  ;  Canada  and 
foreign  countries,  $3;  single  copies,  30  cents.  Changes  of  address  should  be  submitted 
two  weeks  in  advance  of  publication  date  to  insure  receipt  of  current  issue.  Entered  as 
second  class  matter  February  8,  1932,  at  the  Post  Ofifice  at  New  York,  N.  Y.,  under  the 
act  of  March  3,  1879.  Entire  contents  copyrighted/ 1949  by  International  Projectionist 
Publishing  Co.,  Inc.  International  Projectionist  is  not  responsible  for  personal  opinions 
appearing  in  signed  articles  in  its  columns. 


MONTHLY   CHAT 


THAT  projection  is  not  a  static  art  is 
readily  apparent  to  anyone  who  reflects 
but  a  moment  on  the  many  extensive  ad- 
vances in  equipment  racked  up  by  enter- 
prising manufacturers  during  the  past 
couple  of  years,  with  even  more  notable 
improvements  slated  for  the  immediate 
future.  The  non-technical  people  in  the 
industry  are  all  too  prone  at  times  to  scoff 
at  the  designation  of  projection  as  an 
"art,"  their  view  being  that  it  is  purely  a 
mechanical  process  which  involves  merely 
the  throwing  of  a  switch  or  the  pressing 
of  a  button. 

We  regret  that  these  scoffers  can't 
spend  just  one  day,  an  average  tour  of 
duty,  in  a  modern  projection  room  which 
is  outfitted  with  the  latest  equipment. 
They  would  quickly  find  out — and  would 
undoubtedly  be  startled  by  their  discov- 
ery— that  arc  lamps  burning  super  high- 
intensity  carbons  and  pulling  currents 
ranging  up  to  180  amperes  are  not  ex- 
actly the  type  of  toy  one  would  give  to  a 
child  with  which  to  play. 

Probably  the  best  job  over-all  was  done 
by  the  manufacturers  of  arc  lamps  and 
carbons  who,  working  smoothly  together, 
really  went  to  town  on  these  units.  The 
carbon  people  state  flatly  that  the  only 
limitation  to  carbon  trims  which  would 
pull  350  amperes  is  the  lamphouse  itself. 
This  is  no  reflection  on  the  lamp  manu- 
facturers, who  have  had  to  lick  some 
formidable  problems  to  produce  the  pres- 
ent lamps. 

And  just  consider  the  fine  job  done  by 
the  lens  manufacturers  over  the  past  sev- 
eral years.  In  this  very  isue  is  the  an- 
nouncement of  a  new  series  of  long  focal 
length  lenses  which  should  effect  a  tre- 
mendous improvement  in  screen  illumi- 
nation in  drive-ins  and  in  the  larger 
theaters. 

Nor  have  the  projector  manufacturers 
been  idle.  IP  is  aware  of  several  projec- 
tor developments  of  far-reaching  signifi- 
cance, but  it  is  not  privileged  to  reveal 
the  facts  at  this  time.  In  the  very  near 
future,  however,  the  wraps  will  be  off 
these  advances. 

On  the  whole,  the  manufacturers  of 
projection  equipment  have  nothing  to 
excuse  or  to  gloss  over.  They've  done  a 
bang-up  job  over  the  past  few  years;  and 
it  is  to  be  regretted  that  those  same  peo- 
ple who  deride  projection  as  a  wholly 
mechanical  process,  do  not  display  the 
same  degree  of  initiative  shown  in  the 
design  and  production  of  much  fine 
equipment  by  spending  a  small  portion 
of  their  box-office  take  to  replace  their 
old,  outmoded — "obsolete"  is  the  more 
accurate  term — units  which  can't  pos- 
sibly give  a  good  screen  image. 

Static,  indeed,  The  projection  field 
could  lend  more  than  a  bit  of  its  own 
dynamism  with  which  to  impregnate  a 
few  undersides  in  exhibitor  ranks. 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


(gmttnga  tor  (MpcUAmsa 

ana   93 est    Wishes   tor 
f^roSperitu   ana   J^ecurltu  for    1950 


/ 


rom 


Chicago  Local  No.  110 
I  .  A.  T.  S.  E. 
&      M.      P.      M.      O. 


EUGENE  J.  ATKINSON 

Business  Manager 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


iNTERNATIONAL    PROJECTIONIST 


VOLUME  XXIV 


DECEMBER  1949 


NUMBER  12 


The  35-mm  Projection  Positive  Film 


By  ROBERT  A.  MITCHELL 
//.    The  Manufacture  of  Film 


THE  photographic  films  which  provide 
an  almost  limitless  world  of  entertain- 
ment for  the  patrons  of  the  90,000 
motion  picture  theaters  of  the  world  rep- 
resent a  magical  combination  of  diverse 
products.  Fluffy  white  cotton,  glittering 
ingots  of  silver,  carboys  of  fuming  acids, 
gelatine  from  the  slaughterhouse,  bromine 
from  alkali  brines,  and  a  host  of  materials' 
created  by  modern  chemical  wizardry 
undergo  a  miraculous  transformation  in 
the  factories  of  Eastman  Kodak,  Du  Pont, 
et  al.,  and  eventually  emerge  in  the  form 
of  plastic  ribbons  35  millimeters  (1.378 
inches)  in  width,  coated  with  light-sensi- 
tive emulsions  and  perforated  along  the 
edges. 

The  manufacture  of  film  involves  five 
distinct  processes,  or  operations,  namely: 

1.  Preparation   of  the  film-base   plastic. 

2.  "Casting"  the  film  base. 

3.  Preparation  of  photographic  emulsion. 

4.  Coating  the  base  with  emulsion. 

5.  Slitting  the  sensitized  film  into  35-mm 
ribbons  and  perforating  them. 

Both  nitrate  and  acetate  film  base  are 
cellulose  plastics.  Cellulose  is  a  compound 
familiar  to  everyone.  This  page  consists 
largely  of  cellulose.  Wood  is  also  an  im- 
pure form  of  the  substance.  Cotton  is 
almost  pure  cellulose.  Only  the  very 
purest  commercially  available  form  of 
cellulose — cotton — will  do  for  film  base. 
And  as  pure  as  cotton  is,  the  manufactur- 


ers of  film  subject  it  to  exhaustive  physi- 
cal and  chemical  purifying  treatments 
before    using   it. 

Esterification  Reactions 

The  purified  cotton  is  "nitrated"  to 
make  nitrate  film,  or  "acetylated"  to 
make  safety  film.  These  chemical  proc- 
esses are  called  esterification  reactions 
because  the  nitrated  and  acetylated  prod- 
ucts formed  by  them  are  "esters"  of 
cellulose. 

The   nitration   of   cellulose    involves    a 


At  Kodak   Park,  motion  picture  film  is  slit  to 
the  proper  widths  on  machines   like   this. 


chemical  reaction  between  cotton  and 
nitric  acid.  These  two  substances  ex- 
change certain  groups  of  atoms  which 
they  contain:  the  cellulose  gives  nitric 
acid  "hydroxyl"  groups  in  return  for 
"nitrate"  groups  from  the  acid.  This 
molecular  activity  transforms  the  cellu- 
lose into  nitrocellulose,  the  chief  ingredi- 
ent of  nitrate  film  base,  and  the  nitric 
acid  into  water. 

The  formation  of  water  in  this  reaction 
is  undesirable,  however,  because  it  tends 
to  stop  the  nitration  of  the  cotton.  The 
chemist  hurdles  this  difficulty  by  adding 
strong  sulfuric  acid  to  the  nitric  acid. 
Sulfuric  acid  combines  with  the  water  as 
rapidly  as  it  is  produced  to  form  hy- 
drates, and  this  makes  it  possible  for 
the  exchange  of  hydroxyl  and  nitrate 
groups  to  continue  until  the  cotton  is 
nitrated  to  the  desired  degree. 

The  nitrated  cotton  used  in  film  base 
is  a  mixture  of  the  lower  nitrocelluloses 
— chiefly  cellulose  tetranitrate.  Guncot- 
ton,  a  mixture  of  the  higher  cellulose 
nitrates,  would  result  from  continued 
nitration. 

Although  the  general  principle  of 
acetylation  is  the  same  as  that  of  nitra- 
tion, it  is  somewhat  more  complicated 
in  both  theory  and  practice.  Instead  of 
the  nitric-sulfuric  acid  mixture,  special 
reactants  derived  from  acetic  acid  or 
acetic  anhydride  are  employed.  More- 
over, the  acetylating  reaction  must  be 
followed  by  "hydrolysis"  to  reduce  the 
rather  high  degree  of  acetylation  of  the 
cotton  to  the  degree  required  in  the  final 
product. 

A  very  highly  acetylated  cellulose  has 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


desirable  characteristics — toughness,  flex- 
ibility, resistance  to  heat  and  moisture, 
etc..  but  unfortunately  there  are  no  suit- 
able solvents  in  which  to  dissolve  it  for 
the  film-casting  process.  A  reduction  in 
the  number  of  acetate  groups  of  atoms 
attached  to  the  cellulose  molecule  is  the 
purpose  j)f  the  hydrolysis  reaction. 

The  older  safety-film  bases  were  usu- 
ally made  from  cellulose  diacetate,  a 
substance  very  soluble  in  a  number  of 
organic  solvents.  But  in  comparison  with 
nitrate  film,  the  diacetate  film  had  poor 
wearing  quality  and  an  excessive  ten- 
dency to  swell  when  wet  and  to  become 
brittle  when   dry. 

The  new  and  superior  cellulose  triace- 
tate used  for  high-acetyl  safety  film  is 
prepared  by  carrying  the  hydrolysis  only 
a  fraction  of  the  amount  employed  in 
the  manufacture  of  the  diacetate.  Cellu- 
lose triacetate  shares  to  some  extent  the 
desirable  qualities  of  the  higher  acetates, 
yet  it  is  sufficiently  soluble  in  certain 
organic  solvents  to  be  made  into  film. 

Preparation  of  Film  Base 

The  purified  and  dried  nitrocellulose 
or  cellulose  acetate  is  dissolved  in  vola- 
tile solvents  to  make  a  syrupy  "dope" 
suitable  for  the  film-casting  process.  Sol- 
vents used  to  dissolve  nitrocellulose  in- 
clude various  mixtures  of  diethyl  ether, 
methyl  alcohol,  ethyl  alcohol,  isoamyl 
alcohol,  acetone,  methylethyl  ketone,  iso- 
amyl acetate,  ethyl  acetate,  butyl  acetate, 
and  various  "Cellosolves,"  of  which  1-eth- 
oxyethan-2-ol  is  representative. 

The  solvent  mixtures  for  cellulose 
triacetate  usually  contain  considerable 
proportions  of  dioxane. 

Various  materials  which  improve  the 
flexibility,  toughness,  and  wearing  qual- 
ity of  the  finished  film  are  incorporated 

One  of  many  gigantic  machines  at  Eastman's 
Kodak  Park  which  convert  the  honeylike  sub- 
stance known  as  "dope"  into  endless  sheets  of 
the  familiar  transparent  film  base.  The  mate- 
rial is  so  clear  as  to  be  nearly  invisible  as 
it   passes   through    the   machine. 


INTERNATIONAL    PROJECTIONIST 


txtmbz  tn  all  xU  frtettfo 


% 


g>m$mx  a  (Smttttga 


into  the  dope  before  casting.  These  film- 
improving  materials,  called  plasticizers, 
include  such  substances  as  camphor,  cas- 
tor oil,  ethyl  phthalate,  butyl  phthalate, 
and  tricresyl  phosphate.  Plasticizers  are 
used  in  both  nitrate  and  high-acetyl  ace- 
tate film. 

By  film  "casting"  is  meant  the  opera- 
tion of  spreading  out  the  honeylike  dope 
on  a  polished  surface  in  order  to  expel 
the  volatile  solvents  and  obtain  a  thin 
pelicle  (film)  of  cellulose  plastic-cellu- 
lose ester  mixed  with  plasticizers. 

The  film-casting  machine  is  a  large 
and  complex  apparatus.  All  air  admitted 
to  the  film-casting  room  is  washed  free 
of  dust  and  conditioned  as  to  temperature 
and  humidity;  and  the  machine,  itself, 
is  kept  scrupulously  clean. 

The  heart  of  the  film-casting  machine 
is  a  metal  drum  which,  in  some  installa- 
tions, is  20  or  more  feet  in  diameter. 
(An  endless  metal  belt  is  sometimes  used 
in  place  of  the  drum.)  The  outer  rim  of 
the  drum  is  several  feet  in  width  and 
very  highly  polished. 

Application  of  'Dope' 

Dope  is  applied  to  the  rim  of  the 
slowly  revolving  drum  by  means  of  a 
special  spreading  arrangement  which 
allows  the  thickness  of  the  film  to  be 
controlled.  The  speed  at  which  the  drum 
revolves  is  such  that  the  greater  part  of 
the  volatile  solvents  evaporates  from  the 
film  of  dope  before  one  complete  revolu- 
tion has  been  made.  An  aspirating  ven- 
tilator placed  over  the  rim  of  the  drum 
hastens   solvent    evaporation. 

The  coagulated  film  of  nitrate  or  ace- 
tate base  is  continuously  detached  from 
the  drum  and  drawn  away  by  a  separate 
roller.  The  film,  several  feet  in  width,  is 
so  transparent  as  to  be  nearly  invisible  as 
it  passes  through  the  remainder  of  the 
film-casting  machine. 

Various  other  rollers  complete  the  dry- 
ing operation,  and  the  film  is  finally 
wound  up  to  await  the  emulsion-coating 
process. 

The  pale  yellow  light-sensitive  coating 


applied  to  one  side  of  the  transparent 
film  base  (to  both  sides  in  the  case  of 
duplitized  stock)  is  called  the  emulsion. 
The  term  "emulsion"  signifies  a  suspen- 
sion of  minute  particles  of  one  substance 
in  another,  the  two  substances  being  im- 
miscible, or  insoluble,  in  one  another. 

Preparation   of  Emulsion 

An  emulsion  is  not  a  true  solution. 
Kerosene,  for  instance,  is  immiscible  with 
water.  But  if  a  little  kerosene  is  added 
to  water  and  the  mixture  shaken  very 
vigorously,  a  milky  fluid  is  obtained.  The 
whitish  mixture  is  an  emulsion  of  kero- 
sene droplets  suspended  in  water. 

An  emulsion  of  kerosene  and  water 
breaks  down  very  quickly,  the  two  liquids 
separating,  unless  an  emulsifier  is  added. 
Soap  acts  as  an  emulsifying  agent  for 
kerosene  in  water;  so  if  a  small  piece  of 
soap  is  shaken  up  with  the  two  im- 
miscible liquids,  a  milky-white  suspension 
is  obtained  which  lasts  a  long  time. 

The  same  phenomena  are  observed  in 
the  case  of  liquids  and  solids  which  are 
insoluble  in  them.  The  chief  light-sensi- 
tive ingredient  of  photographic  emulsions 

35-mm  processing  machine  at  Kodak  Park 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


His  pen-and-ink  people  live  for  laughter... 


BORN  on  the  drawing  board,  though 
they  are,  these  little  people  have  the 
breath  of  life  and  laughter  that  captures 
hearts  the  world  around — thanks  to  the 
creative  genius  of  the  animator. 

His  knowing  lines  belie  the  fact  that 
they  are  folk  of  fantasy . . .  of  pen  and  ink 
and  paint.  For  each  and  every  one  has 
the  human  touch  . .  .  has  been  fully  en- 
dowed with  character  and  lifelike  move- 


ment, through  the  animator's  artistry. 
Yet — for  all  his  wit  and  skill — the 
animator  could  not  present  his  gift  of 
laughter  to  the  moviegoing  world  with- 
out the  help  of  film.  And  this — in  types 
especially  adapted  to  his  needs — he  finds 
in  the  famous  Eastman  family,  whose 
Fine  Grain  Master  Positive  and  Back- 
ground X  Negative  have  been  the  ani- 
mator's faithful  mediums  for  many  years. 


EASTMAN    KODAK    COMPANY 

ROCHESTER    4,    N.    Y. 

J.  E.   BRULATOUR,    INC.,    DISTRIBUTORS 
FORT    LEE     •     CHICAGO     •     HOLLYWOOD 


PROJECTS  21,000  LUMENS  AT  90  AMPERES  COMPARED  TO 
17,000  LUMENS  FOR  THE  70-AMPERE  SUPREX  AND  7,000  LUMENS 
FOR  THE  1   K.W. 

MASSIVE  LAMPH0USE 

FORCED  AIR  COOLING  OF  CARBON  FEED  MECHANISM 

*  LOW  OPERATING  TEMPERATURES 

*  RUGGED  BURNER  MECHANISM 

*  LIGHTRONIC  AUTOMATIC  FOCUS  CONTROL 
SYSTEM 

*  SIMPLICITY  OF  CARBON  FEED  RATE  ADJUST- 
MENT-THE  ONE  CONTROL  IS  SET  TO  DESIRED 
AMPERAGE 

ic  BI-METAL  LIGHTRONIC  TUBE  CONTROLS  BOTH 
MOTORS  TO  CORRECTLY  FEED  THE  CARBONS 

*  BIG  16&-INCH  REFLECTOR  MATCHES  HIGH 
SPEED  f  1.9  LENS. 

*  AIR  STREAM  STABILIZATION  OF  ARC  BURNING 

*  COMPLETE  COMBUSTION  OF  BLACK  SOOT 

*  WHITE  DEPOSIT  ON  REFLECTOR  PREVENTED 
ic  UNIT  CONSTRUCTION   PERMITS   INSTANT  RE- 
MOVAL OF  MAJOR  COMPONENTS 


i>i>i>i>C>C>[>C>[>[>Ot>C>C> 

Use  coupon  now  to  arrange  free  demonstration 
in  your  own  theatre  or  drive-in. 


THE  STRONG  ELECTRIC  CORPORATION 

I       31  City  Park  Avenue  Toledo  2,  Ohio 

□    I  would  like  a  demonstration  of  the  Strong  Mighty  "90"  in  my 
theatre,  without  cost  or  obligation. 

i  Please  send  free  literature  on  the  □  Mighty  "90";  □  Mogul 
I  Lamp;  □  Utility  Lamp;  □  Strong  Arc  Spotlamps;  □  Strong 
I  Rectifiers;   □  Strong  Reflectors. 


Name. 


I  Theatre. 
Street. . 


I 


LCity  &  State. 


10 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


is  silver  bromide,  an  insoluble  yellowish 
powder.  It  is  clearly  impossible  to  apply 
a  solution  of  silver  bromide  to  gelatine- 
coated  film  base,  because  silver  bromide 
is  insoluble  in  water.  An  emulsion  of  this 
compound  must  therefore  be  prepared 
for  the  film-coating  operation.  Now,  gela- 
tine is  used  as  the  emulsifier  for  emul- 
sions of  silver  bromide  in  water. 

Gelatine  is  a  curious  substance.  When 
dry  it  is  hard  and  glassy.  Purified  pow- 
dered gelatine  is  used  in  commercial  ice 
cream  and  for  making  Jello  desserts. 
Impure  gelatine  is  employed  as  glue  and 
sizing. 

When  placed  in  cold  water,  gelatine 
swells.  The  emulsion  of  film  which  has 
been  sprinkled  with  water  becomes  reticu- 
lated, or  spotted,  because  the  swollen 
gelatine,  upon  drying  and  shrinking, 
causes  the  embedded  silver  particles  to 
shift  their  positions.  When  added  to  warm 
water,  gelatine  dissolves  to  form  solu- 
tions which  are  viscous  and  sticky.  There 
is  no  definite  limit  to  the  solubility  of 
gelatine:  the  more  gelatine  added,  the 
thicker  the  solution  becomes.  And  when- 
ever such  a  solution  of  gelatine  cools, 
it  sets  to  a  jelly. 

Soap,  a  "protective  colloid"  for  kero- 
sene and  water  mixtures,  acts  somewhat 
like  gelatine  in  this  respect;  but  of  the 
two,  gelatine  is  by  far  the  more  effective 
emulsifying  agent. 

The  silver  bromide  for  photographic 
emulsions  is  made  from  silver  nitrate  and 
potassium  bromide  by  chemical  inter- 
action. The  silver  nitrate  is  obtained  in 
the  form  of  colorless  platelike  crystals 
by  dissolving  silver  in  nitric  acid. 

Both  silver  nitrate  and  potassium  bro- 
mide are  salts  which  dissolve  very  readily 
in  water  to  form  clear,  colorless  solutions. 
When  solutions  of  these  two  salts  are 
mixed,  yellow  silver  bromide  is  instantly 
formed  and,  being  insoluble,  precipitates 
to  the  bottom  as  a  fine  sludge. 

If  gelatine  is  added  to  one  or  both  of 
the  salt  solutions  before  mixing  them 
together,  the  silver  bromide  formed  will 
not  settle  out,  but  remains  suspended  in 
the  liquid  as  a  creamy  emulsion. 

Silver  bromide  is  very  sensitive  to 
light,  so  as  to  avoid  spoiling  the  emulsion 
during  its  manufacture,  the  two  gelatine- 
containing  salt  solutions  are  mixed  in  the 
dark  (or  under  a  dim  red  safelight).  In 
certain  cases  a  small  part  of  the  potas- 
sium bromide  is  replaced  by  potassium 
iodide.  This  salt  reacts  with  silver  nitrate 
to  form  silver  iodide,  a  compound  similar 
to  silver  bromide. 

Silver  bromide  is  insensitive  to  red  and 
orange  light,  and  it  reacts  only  feebly  to 
yellow  light.  The  color  response  of  this 
photo-sensitive  compound  may  be  ex- 
tended by  incorporating  special  dyes  into 
the  emulsion.  By  virtue  of  an  energy- 
transfer  process  not  yet  perfectly  under- 
stood, certain  dyes  sensitize  the  silrer 
bromide  to  those  colors  which  thev  them- 


selves absorb. 

The  pink  dyes  used  for  orthochromatic 
negative  emulsions  absorb  yellowish 
green  light,  and  hence  make  the  emulsion 
sensitive  to  yellow  and  green  in  addition 
to  blue,  violet,  and  ultraviolet.  Likewise, 
the  green  dyes  used  for  panchromatic 
emulsions  absorb  red,  thereby  extending 
the  senitivity  of  silver  bromide  into  the 
red  region. 

The  light-sensitivity,  or  photographic 
speed,  of  an  emulsion  may  be  increased 
by  subjecting  it  to  heat  during  its  manu- 
facture. The  most  rapid  emulsions  are 
heated  to  higher  temperatures  and  for 
longer  periods  than  slower  emulsions. 

Coating   and   Final   Stages 

The  coating  of  film  base  with  emulsion 
is  carried  out  on  film-coating  machines. 
The  base  is  first  coated  with  a  substratum 
of  clear  gelatine  to  insure  perfect  adher- 
ence and  uniform  thickness  of  the  emul- 
sion layer.  The  coating  of  positive  and 
orthochromatic  emulsions  on  the  gela- 
tine-coated film  base  may  be  done  under 
red  light,  and  the  slower  panchromatic 
emulsions  under  very  faint  green  light. 
In  the  case  of  the  more  sensitive  emul- 
sions, however,  total  darkness  is  neces- 
sary to  prevent  "fogging"  the  film. 

Anti-halation  coatings  on  the  "blank" 
side  of  negative  film  are  also  supplied  by 
film-coating  machines.  These  coatings 
(which  consist  only  of  colored  gelatin, 
and  are  not  emulsions)  serve  to  reduce 
the  glare  spots  which  blur  the  images  of 
bright  objects  in  a  picture.  Without  such 
a  coating,  the  brighter  rays  of  light  im- 
pinging upon  the  film  pass  through  the 
emulsion  to  the  uncoated  side  of  the  base 
and  are  reflected  back  to  the  emulsion  as 
a  confused  jumble  of  images. 

An  anti-halation  coating  absorbs  most 
of  the  light  passing  through  to  the  back 
of  the  film,  thereby  reducing  reflections 
to  a  minimum.  The  soluble  dyes  em- 
ployed wash  out  of  the  gelatine  backing 
when  the  film  is  developed. 

The  film-coating  machines  work  on  the 
same  principle  as  the  film-casting  ma- 
chines. Coating  rollers  transfer  the  warm, 
liquified  emulsion  to  the  surface  of  the 
film  base.  The  coated  film,  several  feet 
in  width,  passes  through  drying  chambers 


where  the  emulsion  layer  is  congealed. 
The  film  is  automatically  wound  in  large 
rolls  at  the  end  of  the  machine. 

The  wide  film  taken  from  the  film- 
coating  machine  is  cut  lengthwise  into 
ribbons  35  millimeters  in  width  by  film- 
slitting   machines. 

In  the  early  days  of  the  movies  large 
quantities  of  unperforated  35-mm  raw 
stock  were  supplied,  the  sprocket  holes 
being  punched  out  more  or  less  perfectly 
by  machines  belonging  to  the  studios 
and  processing  laboratories.  Today,  how- 
ever, all  the  film  used  in  professional 
motion  picture  work  is  perforated  by  the 
manufacturer  of  the  film,  a  job  requiring 
precision  apparatus  continually  main- 
tained in  first-class  condition  by  frequent 
inspection    and    servicing. 

Before  the  film  is  packed  in  rolls  for 
shipment  to  the  retailers,  it  is  fed  through 
machines  which  light-print  the  manufac- 
turer's name  and  other  identification 
markings  in  the  sprocket-hole  margins. 
[To    be    Continued] 


Q 


eetinai  and 


v^est    lAJiiked 


t> 


fom 


MERLE  H.  CHAMBERLIN 

M-G-M  STUDIOS 
Culver  City 
Calif. 


To  Our  Many  Friends  and  Members  in  the  Craft 


(gmttttJ^H  anin  Seat  Uta^a 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


11 


FOR  STUDIOS  EVERYWHERE  AND  THEATRES  OUTSIDE  U.  S.  A.  AND  CANADA 


Recording  Equipment 

Western  Electric  recording  equipment  is  now  avail- 
able to  studios  everywhere  through  Westrex. 


PHOTOGRAPHIC-MAGNETIC-DISK  RECORDERS 


RA-123TB 

Acomplete  line  of 
recording  equip- 
ment ranges  from 
a  single  -  film 
newsreel  system 
to  elaborate  auto- 
matic equipment 
for  studios. 


RA-112B 
MODULATOR 


( 


/ 


i'bfc'7 


RA-1231 


Reproducing  Equipment 

The  Westrex  line  of  reproducing  equipment  is  available 
to  studio  review  rooms  everywhere,  and  to  theatres  out- 
side U.  S.  A.  and  Canada. 


SOUND  AND  PROJECTION  EQUIPMENT 

Westrex  Master,  Advanced  and  Standard 
Sound  Systems  meet  the  requirements 
of  theatres  of  all  sizes  and  types.  Sound 
Heads  used  in  these 
systems  include  the 
famous  Western 
Electric  Hydro  Flut- 
ter Suppressor. 


RE-RECORDING  AND 
SCORING  CONSOLES 


A  number  of  standard  sizes  and  types  are  avail- 
able and  special  designs  can  be  assembled. 


RE-RECORDERS 


ANNOUNCEMENT 

.,._  u„c  token  over 


.  .        ^t  Western  fciecinw  «-v    r 

D,VTu    S    A    Westrex,  and  Us   21 
',n  -th  offices  in  100  principal 

subsidiaries,  with  offices  in         K 
cities.now  serve  the  need   «f  8 
■in  the  maior  countries  ofthe 

inad/tnU%rnd  Canada, 
outside  the  v.  o-  «• 


AMPLIFIERS 

Westrex  Amplifiers,  from  15  to 
100  watts,  are  mounted  in 
attractive  floor- type  cabinets 
and  are  designed  for  flexibility 
in  arrangement. 

LOUDSPEAKERS 


16  MM 


35  MM 


35  MM     * 


ix, 

WLJm 


Meet  the  needs  of  small,  medium  or  large 
studios  for  100  mil  standard,  100  mil  push- 
pull  and  200  mil  push-pull  re-recording. 


71 3B 

HIGH  FREQUENCY 

UNIT 


754B  L.  F.  OR 
FULL  RANGE  SPEAKER 


TYPICAL  SPEAKER 
SYSTEM 


r* 


HIGH  FREQUENCY  HORN 


Available  in  the  U.  S.  A.  and  Canada  through  manufacturers 
and  distributors  of  reproducing  equipment,  and  to  exhibi- 
tors abroad  through  subsidiaries  of  Westrex. 


Westrex  Corporation 

111    EIGHTH   AVENUE,   NEW  YORK   11,   N.  Y. 


FORMERLY  WESTERN  ELECTRIC  EXPORT  CORPORATION 


The  Garutso  Balanced'  (25-75  mm)  Photographic  Lenses 


IP  is  in  receipt  of  a  communication  from 
E.  Goulden,  Inc.,*  exclusive  agent  for 
Garutso  "Balanced  Lenses,"  which,  cred- 
ited by  their  sponsor  with  the  ability  to 
impart  depth  to  photographic  images, 
have  received  widespread  and,  on  the 
whole,  rather  glowing  sendoffs  from  the 
photographic  trade  press.  The  virtues  of 
these  patented  lenses  are  described  in 
the  appended  verbatim  copy  of  a  state- 
ment by  their  sponsor: 

"A  commercial  set  of  Garutso  lenses  is 
comprised  of  25,  30,  35,  40,  50,  and  75  mm 
focal  lengths.  Inherent  to  all  of  them  are 
unusual  characteristics  that  set  them  far 
apart  from  conventional  lenses  of  similar 
focal  lengths. 

'Variable  Deep  Field  of  Focus' 

"First,  instead  of  a  single  plane  of  focus, 
Garutso  lenses  have  a  variable  and  tremend- 
ously deep  field  of  focus.  This  depth  of  field 
results  from  Mr.  Garutso's  discovery  of  new 
principles  and  is  in  no  wise  produced  by 
special  diaphragm  apertures  or  tricks  of  any 
kind.  The  variability  of  the  field  is  con- 
trolled  by  focus  adjustment  entirely. 

"A  number  of  different  Garutso  lens  for- 
mulae have  been  developed  for  the  modifica- 
tion of  conventional  photographic  objectives 
of  different  types  and  focal  lengths.  While 
these  formulae  differ  among  themselves,  they 

*  5746  Sunset  Blvd.,  Hollywood  28,  Calif. 


all   embody  the   same  optical   balance   prin- 
ciples. 
Cite  Two  Major  Improvements 

"In  general,  the  Garutso  modification  ac- 
complishes two  major  improvements:  (1) 
the  focal  depth  of  the  modified  objective  is 
increased,  and  (2)  the  definition  and  con- 
trast of  the  image  is  greatly  enhanced  by  a 
substantial  reduction  in  the  vestigial  spheri- 
cal  aberration  of  the  conventional  lens. 

"Previous  attempts  to  accomplish  the  in- 
crease in  depth  of  focus,  first  above-men- 
tioned, have  had  no  success  because  the 
modifying  elements  used  have  introduced 
other  undesirable  aberrations. 

"The  diaphragm,  instead  of  being  used  to 
create  an  illusion  of  increased  focal  depth 
by  means  of  small  apertures  as  in  conven- 
tional lens,  is  employed  in  the  Garutso  lens 
to  increase  the  plasticity  of  the  photograph, 
thereby  intensifying  the  three-dimentional 
effect. 

"The  Garutso  balanced  lens  provides  a 
negative  of  uniform  density  throughout  the 
entire  field  at  all  apertures." 

Following  careful  consideration  of  the 
foregoing,  as  well  as  of  other  data  relat- 
ing to  the  Garutso  lens,  IP  is  constrained 
to  make  the  following  observations: 

For  a  given  sharpness  of  image  at  a 
given  focal  length  of  the  lens  and  a  given 
aperture,  all  lenses  have  and  always  will 
have  a  given  depth  of  focus. 


There  are  three  methods  by  which  one 
may  achieve  depth  of  focus:  (1)  reduce 
the  focal  length  of  the  lens;  (2)  diminish 
the  size  of  the  aperture,  and  (3)  reduce 
the  sharpness  of  the  image.  This  last- 
named  condition  would  seem  to  be  a 
major  function  of  the  Garutso  lens,  with 
results  that  were  strikingly  apparent  in 
the  motion  picture  "Citizen  Kane,"  pro- 
duced by  Orson  Welles  some  years  ago. 

The  foregoing  is  as  much  a  natural 
law  as  is  the  fact  that  if  one  stepped  out 
of  a  ten-story  window  the  chances  would 
be  excellent  that  one  would  break  his 
neck.  We  need  not  confuse  this  issue 
with  considerations  of  aperture  opening, 
lens  speed,  or  the  amount  of  light  on  a 
given  set.  These  fundamental  laws  pre- 
vail and  are  at  once  controlling  and  in- 
controvertible^— even  in  Hollywood. 

It  is  an  astonishing  thing  that  nobody 
in  Hollywood  has  yet  lent  acceptance  to 
the  principle  that  we  shall  reduce  the 
sharpness  of  the  foreground  images. 


TESMA's  New  Headquarters 

The  home  office  of  TESMA  (Theater 
Equipment  Supply  Manufacturers  Assoc.) 
is  now  located  at  1938  Hillhurst  Ave.,  Hol- 
lywood 27,  Calif.  The  phone  number  is 
NOrmandy  7747.  The  engaging  secretary 
of  the  Association,  Roy  Boomer,  is  render- 
ing the   same  fine  service   as  of  yore. 


-^^■^^f-^^^^^m^m^m^^^tm^^t^m^i^-^^^m^^.  i^^^m^i^^^^m^^^. 


INTERNATIONAL  PROJECTOR  CORPORATION 


Extends  To  All  Its  Friends 


d5edt     l/UldkeA    for    a    ^rrappu    ^rrolldt 
and    a    f^robperouS     1950 


f 


'SIMPLEX  Projectors  and  Sound  Systems" 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


13 


FIG.   1.    Screen   light  with    13.6-mm   super  high-intensity  carbons  vs. 
burning  rates — no  film  or  shutter. 


FIG.  2.    Efficiency  of  conversion  of  carbon  into  light  energy  vs.  the 
amount  of  light  produced. 


1 

At  f**Mt*rv*i  LmHT 

3 

\ieoo 
« 

i 

v. 

5  iooo 

*HiTmX"'Su*£X  Cammoh  \_ 

1 

I 

&.o  Jo*** 
X 

X 

\ 

X 

600 

: 


Burning  Rates — Inches  Per  Hour 


Thousands  of  Screen  Lumens — No  Film  or  Shutter 


The  New  13.6-mm  National  Hitex 
Super  High-Intensity  Carbon 


RECENT  years  have  witnessed  an  ever- 
increasing  demand  for  higher  levels 
of  light  for  motion  picture  screens, 
and  this  demand  is  by  no  means  limited 
to  the  huge  screens  utilized  for  drive-in 
theaters.  On  the  contrary,  exhibitors 
everywhere — large  theaters  and  small — 
evidence  a  growing  awareness  of  the 
dividends  in  patron  satisfaction  which 
accrue  as  the  result  of  a  well-lighted 
screen  image. 

Concerted  action  by  both  carbon  com- 
panies and  arc  lamp  manufacturers  has 
resulted  in  a  sharp  revision  upward  in 
the  amount  of  screen  light  available  for 
all  types  of  theater  operations.  The  latest 
contribution  to  this  advance  in  the  art  is 
National  Carbon  Co.'s  new  13.6-mm 
"Hitex"  carbon,  designated  as  a  super 
high-intensity  and  having  a  rating  of 
from  170  to  180  amperes. 

Distribution  of  these  Hitex  super  car- 
bons is  as  yet  on  a  very  restricted  basis, 
since  only  a  limited  number  of  them  is 
being  produced. 

Comparison  With  Old  Super 

A  true  measure  of  the  efficiency  of  the 
Hitex  super  carbon  may  be  had  only  by 
comparison  with  former  "super"  high- 
intensity  13.6-mm  types.  The  first  of 
these,  produced  by  National  in  1936,  had 
a  peak  operating  rating  of  180  amperes 
and  constituted  a  great  improvement  in 
both  quantity  and  distribution  of  light 
over  other  carbons  then  available. 

Convincing  evidence  of  the  effect  of 
continuing  research  and  improved  meth- 


ods of  manufacturing  lies  in  the  fact 
that  only  five  years  later,  in  1941,  an 
improved  super  high-intensity  was  intro- 
duced by  National  which,  rated  at  170 
amperes,  produced  20%  more  light  than 
did  the  1936  type,  this  with  a  10-ampere 
reduction  and  no  increase  in  burning 
rate! 

Compared  with  the  old  super-high  in- 
tensity carbon  (1941),  this  new  Hitex 
carbon  gives  a  higher  light  output  of 
better  quality  (whiter)  ;  longer  life,  and 
greater  efficiency  in  terms  of  converting 
carbon  into  light  energy — all  without  any 
measurable  increase  in  total  energy 
(heat)   at  the  aperture. 

'Hitex'  Operating  Characteristics 

Operating  characteristics  of  the  Hitex 
carbon  are  given  in  Table  A.  These  data 
represent  measurements  made  on  a  typi- 
cal condenser  system  and  provide  a  direct 
comparison  of  performance  with  the  old 
super  carbon  under  the  conditions  de- 
scribed. 

It  will  be  noted  that  at  the  low  end 
of  its  rated  amperage  the  Hitex  carbon 
approximately  matches  the  amount  of 
light  produced  by  the  old  super;  while 
at  its  peak  current  rating  the  Hitex  de- 
livers approximately  15%  more  measur- 
able light  than  the  old  super. 

The  light  output  of  any  carbon  arc 
projection  setup  depends  upon  a  number 
of  variable  factors,  one  of  the  most  im- 
portant of  which  is  the  distribution  ratio 
of  light  over  the  entire  screen  surface, 
that  is,  from  the  center  to  either  side.  At 


80%  center-to-sides  distribution  ratio 
(considered  a  very  efficient  distribution) 
the  light  output  of  the  old  super  is  mid- 
way of  the  output  of  the  Hitex  carbon 
at  its  low  and  high  ends  of  rated  oper- 
ating current. 

Thus,  if  the  Hitex  carbon  be  operated 
at  its  lowest  current  rating,  its  light  out- 
put will  fall  just  short  of  that  of  the  old 
super;  but  at  its  highest  rated  operating 
current  it  will  give  above  15%  more  light 
than  does  the  old  super. 

Economy  of  Operation 

How  much  light  output  may  be  had  at 
what  cost  is  a  vital  question  for  every 
type  of  theater  operation.  The  answer 
may  be  arrived  at  by  plotting  the  screen 
light  against  the  burning  rate  of  the 
carbon  in  inches  per  hour,  thus  permit- 
ting a  determination  of  just  how  much 
light  is  obtained  at  various  burning  rates 
and  at  what  cost  per  hour.  Such  data  is 
given  in  Fig.  1,  which  includes  the  data 
shown  in  Table  A. 

It  will  be  noted  in  Fig.  1  that  the  data 
given  for  both  the  Hitex  and  the  old 
super  carbons  cover  different  burning 
rate  ranges,  but  this  does  not  obscure 
the  fact  that  the  Hitex  is  by  far  the  more 
economical  of  the  two — that,  in  fact,  the 
Hitex  carbon  has  a  longer  life  by  a  mar- 
gin of  from  30  to  40%. 

Reduced  to  practical  operating  terms, 
these  figures  mean  that  at  170  amperes 
each  Hitex  carbon  will  project  three 
double  reels  of  film,  as  contrasted  with 
the  two  double  reels  projected  by  the  old 


14 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


super — an  extension  of  50%  in  burning 
time  at  this  amperage.  At  the  high  end 
of  its  rated  current,  180  amperes,  the 
Hitex  will  project  two  double  reels  and 
one  "short"  reel. 

As  is  well  known,  increased  light  with 
a  given  projection  setup  means  higher 
amperage  and  a  faster  burning  rate  for 
the  carbon,  as  is  plainly  indicated  in 
both  Table  1  and  Fig.  1.  The  light  output 
of  a  given  carbon  divided  by  its  burning 
rate  indicates  the  total  amount  of  light 
energy  produced  per  inch  of  carbon 
burned  and  measures  the  degree  of  effi- 
ciency of  conversion  of  the  carbon  into 
light  energy. 

Much  Higher  Conversion  Rate 

This  efficiency  of  conversion  is  shown 
in  Fig.  2,  wherein  the  lumen-hours  per 
inch  of  carbon  are  plotted  against  the 
correlative  value  of  screen  lumens  pro- 
duced. It  will  be  seen  that  the  use  of 
higher  currents  with  a  resultant  increase 
in  light  with  a  given  carbon  effects 
some  decrease  in  efficiency.  In  terms  of 
efficiency,  it  is  obvious  from  Fig.  2  that 
for  the  production  of  the  same  amount 
of  light  the  Hitex  carbon  is  from  30  to 
50%  more  efficient  than  the  old  super. 

Electrical  power  consumption  for  the 
operation  of  a  carbon  arc  is  proportional 
to  the  arc  current  pulled  by  the  arc  from 
either  a  local,  constant-voltage  d-c  gen- 
erator or  direct  from  the  power  com- 
pany's d-c  line.  The  degree  of  efficiency 
with  which  power  is  converted  into  light 
is  expressed  in  lumens-per-ampere,  which 
ia  the  amount  of  light  produced  divided 
by  the  arc  current. 

These  data  are  set  forth  in  Fig.  3  in 
which  the  degree  of  efficiency  is  plotted 
against  the  amount  of  light  produced  at 
a  given  current.  Evident  is  the  increase 
in  efficiency  of  conversion  of  power  into 
light  as  the  current  and  the  amount  of 
light  produced  are  boosted.  Equally  evi- 
dent is  the  fact  that  at  the  same  light 
levels  the  Hitex  carbon  matches  the  old 


TABLE    A.     Characteristics   of    13.6-mm    old    and    new    National    super    high-intensity    projector 
carbons  under  typical   operating   conditions. 


Old  Super 

New  'Hitex 

Super 

fcrc  Amperes 

170 

170 

180 

Arc  Volts 

75 

70 

74 

Positive  Consumption  Rate 
(inches  per  hour) 

24.0 

16.0 

21.5 

Screen  Lumens  at  Maximum  Light* 

21,500 

20,700 

24,800 

Side-to-Center  Screen  Distrib- 
ution Ratio  at  Maximum  Light 

65 

60 

60 

Screen  Lumens  at  80^  Screen 
Distribution** 

18,500 

17,500 

19,300 

*  Screen  lumens  with  no  projector  shutter,  film  or  filters;   condensers  at   F:2.0  adjusted  for  maximum 
light. 

'*  Same,  except  that  condensers  are  adjusted  for  80%  side-to-center  screen  light  distribution  ratio. 


super  carbon  in  power  conversion  effi- 
ciency— an  important  point  when  the 
other  advantages  of  the  Hitex  carbon  are 
considered. 

Spectral  Characteristics 

Color  temperature  is  an  important  fac- 
tor in  the  performance  of  any  carbon, 
since  this  is  the  governing  factor  in  the 
quality  of  the  light  projected  on  the 
screen.*  Fig.  4  is  a  spectral  energy  dis- 
tribution curve  for  both  the  Hitex  and  the 
old  super  carbons  at  maximum  light  at 
the  center  of  the  screen,  with  both  arcs 
pulling  170  amperes  and  no  film  being 
projected.  The  color  temperature  figures 
are  5925°  for  the  old  super,  and  6250° 
for  the  Hitex  carbon,  with  the  latter  hav- 
ing the  appearance  of  a  whiter  light. 

As  indicated  previously,  the  Hitex  car- 
bon gives  approximately  15%  more  meas- 
urable light  per  unit  of  heat  at  the  aper- 


*  "Color  Temperature:  Origin  and  Meaning,"  by 
W.  W.  Lozier;  IP  for  November  1947,  p.  S. 


ture  than  does  the  old  super.  On  this 
account,  the  Hitex  carbon  burned  at  180 
amperes  does  not  give  more  total  energy 
at  the  aperture  than  does  the  old  super. 
This  means  that  the  Hitex  carbon  will 
enable  a  great  increase  in  light  without 
in  any  way  aggravating  the  problem  of 
heat  on  the  film. 

Recommended  for  use  with  the  Hitex 
carbon  over  its  entire  current  rating  is 
the  National  Orotip  1/2-inch  heavy-duty 
negative  carbon. 

The  old  super  13.6-mm  carbon  gave 
best  results  when  the  negative  was  ap- 
proximately centered  on  the  positive  cra- 
ter face.  With  the  Hitex  carbon,  optimum 
stability,  light  output  and  burning  ra'e 
are  obtained  when  the  negative  is  posi- 
tioned a  bit  lower  so  that  it  centers  on 
the   positive   crater   face. 

The  terms  "Hitex,"  "National"  and 
"Orotip"  are  registered  trade-marks  of 
National  Carbon  Company,  Inc. 


FIG.    3.     Efficiency   of   conversion   of   electrical    power 
amount  of  light  produced. 


into    light    vs. 


/*  /<»  /»  eo  ia  **  it 

Thousands  of  Screen  Lumens — No  Film  or  Shutter 


FIG.  4.    Spectral  energy  distribution  of  light  at  center  of  projection 

screen  at  maximum  light  at  170  amperes — no  film.    Curves  adjusted 

to   approximate   same    visual    intensity   of   illumination. 


Is 

^""""^^* 

.„ 

OLo    J Or MX. 

wo  soeo  tooo  7ooc 

Wavelength — Angstroms 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


15 


Full  Text  of  California  Supreme  Court  Decision  on 
Local  Union  Membership  Acceptance,  Rejection 


SO  intense  and  widespread  was  the  in- 
terest generated  by  the  publication 
herein  last  month*  of  a  summary  of  the 
decision  of  the  Supreme  Court  of  Cali- 
fornia regarding  the  "right"  of  an  out- 
side IA  member  to  gain  full  membership 
in  another  IA  Local  Union,  even  after  a 
period  of  temporary  employment  in  the 
latter's  jurisdiction,  that  IP  has  decided 
to  publish  the  decision  of  the  Court  in 
full. 

The  case  concerned  IA  Local  162  of 
San  Francisco  and  two  men  from  distant 
states  who,  on  the  basis  of  their  IA  mem- 
bership in  other  IA  locals,  deposited 
their  cards  with  Local  162  and  sought 
and  received  employment  in  San  Fran- 
cisco theaters  under  the  jurisdiction  of 
Local  162.  Subsequently,  and  admittedly 
without  having  even  made  application  for 
membership  in  Local  162,  these  men  in- 
stituted a  court  action  to  force  Local  162 
to  admit  them  to  full  membership. 

The  first  round  of  the  contest  in  a  lower 
court  saw  the  decision  go  against  Local 
162  on  the  score  of  admission  to  member- 


*  "High-Court    Ruling    on    Local    Rights," 
Harry  Sherman;  IP  for  Nov.,  1949,  p.  5. 


by 


ship  but  not  on  the  score  of  the  actual 
and  exemplary  damages  sought  by  the 
plaintiffs  on  the  ground  that  they  had 
been  unjustly  deprived  of  their  rights 
to  earn  a  livelihood. 

Local  Union's  Membership  Rights 

Upon  appeal  to  the  Supreme  Court  of 
the  state,  the  decision  of  the  lower  court 
was  sweepingly  reversed  in  every  particu- 
lar. Most  important  is  that  portion  of  the 
court's  judgment  that  jobs  are  vested  in 
the  organization  (in  this  case  Local  162) 
and  not  in  an  individual;  and  further 
that  the  IA  Constitution  specifically  vests 
in  its  local  unions  the  right  to  be  the  sole 
judge  as  to  who  shall  be  admitted  to 
membership. 

The  successful  outcome  of  this  appeal 
was  due  in  no  small  measure  to  the  fine 
work  done  in  the  case  by  Michael  G. 
Luddy,  attorney  on  the  West  Coast  for 
the  IA  General  Office. 

Although  it  is  emphasized  that  in  re- 
versing the  decision  the  Supreme  Court 
remanded  the  case  back  to  the  lower 
court  for  reconsideration  on  an  inclusive 
basis,  it  appears  extremely  doubtful  that 


the  lower  court  would  oppose  the  high 
court's  finding  and  again  approve  full 
membership  for  the  outside  members. 

The  full  text  of  the  Supreme  Court's 
decision,  written  by  the  chief  justice  and 
concurred  in  unanimously  by  the  other 
six  justices  on  the  court,  is  appended 
hereto : 

IN  THE  SUPREME  COURT  OF  THE 
STATE  OF  CALIFORNIA 
Leslie  Dotson  and  Walter  J.  Murrah,  plain- 
tiffs and  appellants,  vs.  International  Alli- 
ance of  Theatrical  Stage  Employees  and 
Moving  Picture  Machine  Operators  of  the 
United  States  and  Canada;  Local  162  there- 
of, et  al,  defendants  and  appellants.  Filed 
Sept.  30,  1949. 

Plaintiffs,  Leslie  Dotson  and  Walter  J. 
Murrah,  sought  a  writ  of  mandate  com- 
pelling defendant  Local  162,  a  labor  organi- 
zation, and  certain  of  its  officers  to  admit 
plaintiffs  to  membership  as  moving  picture 
projectionists.  They  also  asked  an  injunc- 
tion to  restrain  defendants  from  preventing 
their  employment  in  the  area  under  the 
local's  jurisdiction,  general  damages  for 
alleged  loss  of  wages,  exemplary  damages, 
and  restitution  of  claimed  overcharges  in 
dues. 

Defendants  have  appealed  from  portions  of 
a  judgment  which   granted   a  writ  of  man- 

(Continued  on  page  31) 


Reason  5   i^jreetinaS  ^Jo    \Jur  f  ro lectio nist  ^rriends  C^veruwhere 


/ 


rom 


NATIONAL 


THEATRE        SUPPLY 


Division   of  Notional  «  Simplex  •  Bludworth, Inc.  ' 


EQUIPMENT  AND  SUPPLIES  FOR  EVERY  THEATRE  NEED 


"Service  Around  The  Clock" 


^^^t^m^m^m^-m^^^^^m^^^^^ 


16 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


ma/ 


"BRENKERT   new  SW&V&tSffy  LAMP 
projects  the  most  light  ever  put  on  a  screen 
in  both  INDOOR  and  DRIVE-IN  THEATRES 


Drive-in  theatres  all  over  the  country  are  installing  the 
new  Brenkert  Supertensity  Lamp  because  it  puts  more 
light  on  the  large  size  screens  than  ever  before.  It's  a 
natural  too  for  large  indoor  theatres. 

Special  "air  conditioning"  design  principles  cause  the 
f  Brenkert  Supertensity  Lamp  to  operate  under  cool  condi- 
tions. Film  is  kept  cool  at  the  projection  aperture  by  a 
jet-blown  air  stream.  Forced  air-stream  circulation  keeps 
the  super-sized  lamp  house  cool.  A  water-cooled  unit  is 


also  available  for  the  positive  carbon  heat  baffle.  It  is  the 
only  commercial  arc  lamp  designed  to  operate  with  the 
wewtype  13.6mm  carbons. 

•         •         • 

If  you  want  the  brightest  and  most  realistic  projection 
for  your  screen  . . .  if  you  want  to  win  greater  patron  favor 
for  your  indoor  theatre  or  drive-in — better  get  all  the  in- 
formation about  the  new  Brenkert  Supertensity  Lamp  from 
your  RCA  Independent  Theatre  Supply  Dealer. 

*  ®  BRENKERT  LIGHT  PROJECTION  COMPANY— RCA  SUBSIDIARY 


THEATRE   EQUIPMENT 

RAD tO    CORPORATION  of  AMERICA 

ENGINEERING  PRODUCTS  DEPARTMENT  CAMDEN  N.J, 

In  Canada:  RCA  VICTOR  Company  Limited,  Montreal 


Change  dim  screen 


18 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


THEATER  Tv  programs  may  be  re- 
layed by  microwave  radio  relays, 
coaxial  cables,  or  balanced  telephone 
wires.  The  telephone  company  in  certain 
areas  is  already  equipped  to  furnish  all 
three  types  of  transmission  facilities  on 
a  rental  basis  to  certain  Tv  broadcast 
stations  and  networks.  The  services  fur- 
nished include  intercity  transmission  of 
programs  by  coaxial  cable  or  by  micro- 
wave relay,  studio-transmitter  links  and 
remote  pickups  by  cable,  relay,  or  wire. 

Other  organizations  also  are  equipped 
to  furnish  intercity  microwave  relay  serv- 
ice in  certain  areas.  The  principal  prob- 
lems concerning  the  three  methods  of 
relay  will  be  described  briefly. 

By  May,  1949,  the  A.  T.  and  T.  coaxial 
cable  provided  the  primary  means  of 
transmission  of  Tv  programs  from  New 
York  to  Richmond  on  the  East  Coast 
(through  the  cities  of  Philadelphia,  Bal- 


EFFICIENT  TV  TRANSMISSION  FACILITIES,  THE  FRUITLESS  EFFORTS  BY  THEATER 
INTERESTS  TO  WIN  APPROVAL  THEREFOR  FROM  THE  FCC,  AND  THE  ISSUE  OF 
'PUBLIC  NECESSITY  AND  CONVENIENCE'  ARE  DISCUSSED  IN  THIS  SECOND  OF  A 
SERIES  OF  THREE  ARTICLES  ON   DEVELOPMENTS   IN   THE    FIELD   OF  THEATER  TV. 


Los  Angeles.  Telephone  company  offi- 
cials have  recently  stated  that  a  Tv  chan- 
nel from  New  York  to  Los  Angeles  could 
be  made  ready  in  about  a  year  after  the 
service  is  ordered. 

Coaxial  Cable  Facilities 

The  Bell  System  coaxial  cable5  is  pri- 
marily used  to  multiplex  telephone  trans- 
mission. As  many  as  480  telephone  con- 
versations can  be  transmitted  simulta- 
neously on  a  single  channel  of  each 
8-channel  cable  without  mutual  interfer- 
ence. The  relay  and  terminal  equipment 


Theater    Television: 


What,  How  and  When 


By  JOHN  EVANS  McCOY  and  HARRY  P.  WARNERj 


* 


timore,  and  Washington)  ;  from  Phila- 
delphia to  Chicago  (through  the  cities  of 
Pittsburgh,  Cleveland,  and  Toledo)  ; 
from  Cleveland  to  Buffalo;  and  from 
Chicago   to  St.   Louis. 

By  the  same  month,  A.  T.  and  T.  also 
had  in  operation  microwave  radio  relays 
for  transmission  of  Tv  programs  from 
New  York  to  Boston;  Toledo  to  Detroit; 
and  Chicago  to  Milwaukee.  By  the  end 
of  1949,  A.  T.  &  T.  will  have  completed 
network  links  (either  coaxial  cable  or 
radio  relay)  from  Boston  to  Providence; 
New  York  to  Syracuse  (through  Schen- 
ectady and  Utica)  ;  Buffalo  to  Rochester 
Milwaukee  to  Madison;  Philadelphia  to 
Wilmington;  and  from  Toledo  south  to 
Dayton,  Cincinnati,  and  Columbus.  Like- 
wise, a  radio  relay  between  San  Fran- 
cisco and  Los  Angeles   is   planned. 

At  the  present  time,  the  Bell  System 
does  not  contemplate  extension  of  its  Tv 
relay  facilities  across  the  continent  in 
the  near  future.  The  means  for  a  trans 
continental  Tv  network,  however,  now 
exist,  since  the  coaxial  cable,  equipped 
for  long-distance  telephone  service,  has 
been   completed  between   St.  Louis   and 


installed  was  originally  designed  for  this 
purpose.  However,  it  was  recognized  from 
the  first  that  the  bandwidth  of  each  cable 
channel  was  sufficient  to  permit  Tv  trans- 
mission. New  terminal  equipment  must 
be  installed  to  convert  the  cable  for  Tv 
transmissions. 

The  equipment  now  used  on  the  coaxial 
cable  will  permit  transmission  of  a  Tv 
band  or  2.7  megacycles.  This  is  not  suffi- 
cient to  carry  the  full  requirements  of 
the  present  525-line,  4.5-megacycle  stand- 
ard Tv  broadcasts,  but  recent  develop- 
mental work  will  make  possible  wider- 
band  transmission  (up  to  8  megacycles) 
when  the  demand  arises. 

While  current  theater  Tv  has  adopted 
the  525-line  standard  used  by  broadcast 
stations,  full  utilization  of  the  possibili- 
ties of  theater  Tv  may  require  the  use  of 
higher  definition  and  wider-band  trans- 
missions, which  would  raise  a  problem 
as  to  the  suitability  of  the  coaxial  cable 
for  intercity  transmission  of  the  theater 
program*. 

*  Reprinted  from  Vol.  IV,  No.  2,  of  The 
t  Note  :     The  opinions  and  conclusions 


If  color  Tv  is  desired  by  the  theater 
interests,  bandwidths  of  from  8  to  16 
megacycles  probably  would  be  desirable, 
if  not  essential.  At  the  present  time,  no 
extensive  intracity  coaxial-cable  system 
is  available,  but  some  coaxial-cable  links 
are  in  operation  in  New  York  and  other 
cities. 

Stiff   Transmission  Charges 

The  current  coaxial-cable  Tv  rates 
filed  by  the  A.  T.  and  T.  contemplate 
charges  which  raise  a  serious  economic 
question  both  for  Tv  broadcast  stations 
and  theater  Tv.  A  single  channel  between 
two  cities  costs  the  user  $35  a  month  per 
airline  mile  for  eight  consecutive  hours 
each  day,  and  $2  a  month  per  mile  for 
each  additional  consecutive  hour.  Thus, 
for  240  hours  of  service  in  one  month, 
the  rate  would  be  $35  per  airline  mile. 

For  occasional  or  part-time  service,  the 
rate  is  $1  per  airline  mile  for  the  first 
hour,  and  25  cents  per  mile  for  each 
additional  consecutive  15  minutes.  Addi- 
tional charges  are  made  for  the  use  of 
terminal  equipment:  $500  per  month  is 
charged  for  a  connection  to  the  network 
for  eight  consecutive  hours  daily.  This 
inter-connection  charge  for  occasional 
service  is  $200  per  month,  plus  $10  per 
hour  of  use. 

To  complete  the  service  a  Bell  System 
sound  channel  must  be  used,  at  the  regu- 
lar rates  applicable  to  the  frequency- 
modulated  service.  If  two  users  share 
time  on  the  same  channel,  $25  a  month 
per  airline  mile  is  charged  for  four  con- 
secutive hours  of  daily  service,  with  an 
interconnection,  charge  of  $350  for  each 


Typical  Theatre  Tv  Costs 

Returning  to  our  typical  theater  Tv 
operation  in  Cities  A  and  B,  and  assum- 
ing that  City  A  on  the  coaxial  cable  is 
located  89  miles  from  the  nearest  net- 
work city,  and  that  City  B  is  located  35 
miles  from  City  A,  the  monthly  charges 
for  use  of  Bell  System  facilities  for  re- 
ceiving programs  would  include6: 

City  A  must  pay  a  monthly  charge  of 
$4,840  for  use  of  240  hours  per  month 
on  an  8-hour  per  day  basis,  or  $3,640  for 


5  See  two  FCC  Reports  308. 

0  The  airline  distance  from  Philadelphia 
to  Baltimore  is  about  80  miles;  from  Balti- 
more to  Washington,  D.  C,  about  35  miles. 

Hollywood  Quarterly  with  its  kind  permission, 
stated  are  the  personal  views  of  the  authors. 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


19 


120  hours  per  month  on  a  4-hour  per 
day  basis,  if  the  channel  were  shared 
with  another  theater  Tv  group  or  a  Tv 
broadcast  station  in  City  A.  Likewise,  if 
the  theater  group  in  City  B  utilized  a 
Bell  system  microwave  relay  system  to 
obtain  programs  from  City  A,  it  would 
pay  a  monthly  charge  of  $2,626  for  use 
of  240  hours  per  month  on  an  8-hour  per 
day  basis,  or  $1,966  for  the  shared  use 
of  the  channel  on  a  4-hour  basis. 

Concern  over  the  economic  problems 
raised  by  the  A.  T.  and  T.  coaxial  cable 
rates  led  the  Television  Broadcasters 
Association  to  file  a  petition  with  the 
FCC  requesting  suspension  of  the  rates, 
and  a  hearing  upon  the  reasonableness 
of  the  rates  and  legality  and  other  provi- 
sions of  the  tariffs  filed.  On  April  28, 
1948,  the  FCC  ordered  the  hearing,  but 
refused  to  suspend  the  rates.  A  deter- 
mination on  the  reasonableness  of  the 
rates  has  been  postponed  indefinitely. 

Intercity  Hookup  Difficulty 

Meanwhile,  in  the  same  proceeding 
(Docket  8963)  the  FCC  has  taken  evi- 
dence   and    is    considering    one    of    the 


issues  which  also  is  of  concern  to  theater 
Tv.  This  issue  involves  the  validity  of 
the  provision  in  the  A.  T.  and  T.  tariff 
that  a  customer  may  not  connect  intercity 
channels  of  the  telephone  company  with 
intercity  channels  of  others  except  where 
the  telephone  company  cannot  make  facil- 
ities available  upon  reasonable  notice.7 
If  sustained  by  the  FCC,  this  provision 
would    effectively    preclude    the    use    of 


7  By  A.  T.  and  T.  tariff  filings  made  on 
January  14,  1949,  effective  March  1,  1949, 
this  restriction  on  interconnection  was  re- 
laxed somewhat.  For  example,  if  the  cus- 
tomer orders  service  for  a  period  longer  than 
three  months,  in  an  area  where  the  telephone 
company  has  no  intercity  channel  facilities, 
the  customer  must  give  the  telephone  com- 
pany 12  months'  notice.  But  he  will  be  in- 
formed within  three  months  whether  it  will 
have  facilities  between  the  service  points 
within  a  year.  If  such  facilities  will  not  be 
available,  the  customer  may  connect  his  fac- 
ilities with  those  of  the  telephone  company 
until  three  years  from  the  service  date,  and 
he  may  continue  to  connect  thereafter  unlil 
the  telephone  company  has  facilities,  subject 
to  three  months'  notice  from  the  telephone 
company.  However,  the  FCC  has  suspended 
this  tariff  provision  pending  its  considera- 
tion of  the  restriction  on  interconnection. 


intercity  radio-relay  facilities  built  by  the 
theater  Tv  groups,  such  as  the  radio  relay 
contemplated  in  Fig.  1  between  City  A 
and  City  B.  It  would  also  limit  the  use 
that  theater  Tv  might  make  of  the  radio- 
relay  facilities  offered  on  a  common-car- 
rier basis  by  Western  Union. 

The  substantial  capital  costs  required 
for  construction  of  intercity  coaxial-cable 
installations,  together  with  other  difficul- 
ties, appear  to  make  it  improbable  that 
theater  Tv  will  turn  to  the  construction 
of  its  own  intercity  coaxial  cable  to  pro- 
vide a  national  theater  service.  According 
to  A.  T.  and  T.'s  own  figures,  by  the  end 
of  1948  about  4,600  miles  of  intercity  Tv 
channels  had  been  put  into  operation  at 
a  cost  of  approximately  $20,000,000. 
These  figures  include  the  A.  T.  and  T. 
intercity  radio-relay  circuits  described 
hereafter. 

Microwave  Radio  Relays 

The  second  method  available  today  for 
intercity  relay  of  Tv  programs  is  afforded 
by  microwave  radio  relays.  Radio  relays 
constructed  by  A.  T.  and  T.  extend  the 
coaxial-cable  system  from  New  York  to 


New  4-Inch  Diameter,  Long  Focal  Length  Lenses 


LONG  focal  length  lenses  from  5 
through  7  inches  with  a  speed  ranging 
down  to  F:1.9,  designed  especially  for 
large  movie  theatres  and  drive-in  situa- 
tions, are  now  available  from  the  leading 
designers  of  projection  lenses.  Up  to  this 
writing,  official  announcement  of  the 
availability  of  such  lenses  has  been  re- 
ceived from  both  Bausch  &  Lomb  Op- 
tical Co.  and  Kollmorgen  Optical  Co. 

While  such  lenses  have  been  available 
for  quite  some  time  and  in  fact  have  been 
in  use  in  the  Hollywood  studios  for  back- 
ground process  wbrk,  their  widespread 
application  has  been  prevented  by  the 
fact  that  35-mm  projectors  could  not  ac- 
commodate the  comparatively  large  di- 
ameter of  4  inches. 

Projector  Manufacturers  Ready 

By  January  next  all  the  leading  pro- 
jector manufacturers  —  Brenkert,  Cen- 
tury, Motiograph,  and  Simplex — will  be 
ready  to  accommodate  these  new  long 
focal  length  lenses.  Heretofore,  it  was 
necessary  to  return  the  projector  head  to 
the  factory  for  a  special  machining  job, 
at  considerable  expense,  in  order  to  adapt 
the  head  for  such  lenses. 

In  addition  to  having  seen  service  in 
such  studios  as  Paramount,  20  Century- 
Fox,  Warner  Brothers  and  Universal, 
these  new  lenses  have  been  extensively 
field-tested  in  various  theaters  throughout 
the  country  which  adapted  their  projector 
heads  for  this  purpose. 

The  Bausch  &  Lomb  series  comprises 
eight  new  lenses  in  quarter-inch  steps. 
The  six  lens  elements  are  coated  with  an 


anti-reflection  film,  with  the  achromatic 
combinations  cemented  together  with 
heat-resisting,  thermo-setting  materials, 
and  with  the  lenses  hermetically  sealed 
to  prevent  exposure  to  dust  or  vapors. 

The  construction  of  the  Kollmorgen 
4-inch  diameter  lens  follows  closely  that 
of  the  standard  Snaplite.  Use  is  made  of 
a  one-piece,  high-strength  aluminum  alloy 
mount,  with  no  threaded  joints  to  admit 
oil  or  moisture  into  the  lens.  This  mount 
carries  a  gold  anodized  finish  which  is  an 


integral  part  of  the  metal  and  which  con- 
sequently cannot  chip,  peel  or  flake  off. 

Ordering  Data  Required 

It  is  suggested  that  any  situation  con- 
templating the  use  of  these  new  long 
focal  length  lenses  acquaint  the  manu- 
facturer with  full  details  of  their  opera- 
tion, including  make  and  model  of  pro- 
jector, screen  size,  length  of  throw,  etc. 

Appended  is  a  table,  reproduced 
through  the  courtesy  of  Motiograph,  Inc., 
which  gives  specific  data  for  large-screen 
drive-in  theatres. 


Projection 

Throw 

for  Lens- 

-E.F. 

(To  Closest  Foot) 

Picture 

Width, 

Feet 

5% 

5y2 

5% 

6 

6 1/4            6 1/2 

6% 

7 

20 

127 

133 

139 

145 

151          158 

164 

170 

25 

159 

167 

174 

182 

190          197 

205 

212 

30 

191 

200 

209 

218 

227          236 

245 

255 

35 

223 

233 

244 

255 

265          276 

286 

297 

40 

254 

267 

279 

291 

303          315 

327 

340 

45 

287 

300 

314 

327 

341        355 

368 

382 

50 

318 

334 

349 

364 

379        394 

409 

424 

55 

350 

367 

384 

400 

417        434 

450 

466 

60 

382 

400 

418 

436 

455        473 

491 

509 

65 

414 

434 

453 

473 

493        512 

532 

551 

Courtesy, 

Motiograph,    Inc. 

20 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


FIGURE   1 
Typical  two-city  television  relay  system. 

Boston,  from  Toledo  to  Detroit,  and  from 
Chicago  to  Milwaukee.  A.  T.  and  T.  has 
a  radio  relay  under  construction  between 
New  York  and  Chicago,  and  has  applied 
for  FCC  consent  to  construct  other  radio 
relays  between  San  Francisco  and  Los 
Angeles. 

In  addition,  Western  Union  has  a 
radio-relay  system  available  for  use  be- 
tween New  York  and  Philadelphia,  and 
contemplates  an  extension  of  its  system 
to  the  Midwest  and  South.  These  radio 
relays  are  operated  on  a  "common-car- 
rier" basis  and  are  open  to  use  by  Tv 
broadcasters  under  tariff  schedules  filed 
with  the  FCC. 

A.  T.  and  T.  rates  are  the  same  as  those 
in  effect  for  coaxial-cable  inter-city  serv- 
ice The  Western  Union  rates  are  some- 
what different.  Other  privately-owned- 
and-operated  radio  relays  are  in  opera- 
tion in  various  localities. 

A.  T.  and  T.  intercity  radio  relays 
operate  on  the  frequency  band  3700  to 
4200  megacycles,  and  the  Western  Union 
relays  operate  on  5925  to  6425  mega- 
cycles. Both  these  bands  are  allocated 
by  the  FCC  to  "Common-Carrier  Fixed 
Circuits."  The  A.  T.  and  T.  relays  can 
provide  a  bandwidth  of  4  megacycles; 
while  the  Western  Union  New  York-to- 
Philadelphia  relay  is  equipped  to  pro- 
vide a  5-megacycle  bandwith. 

'Balanced'  Wire  Transmission 

Intercity  Tv  relays  are  based  on  line- 
of-sight  transmissions  from  station  to  sta- 
tion, with  intermediate  stations  separated 
by  about  30  miles  between  cities.  The 
problems  involved  in  theater  Tv  use  of 
intercity  relays  are  substantially  the  same 
as  the  problems  stated  previously  as  to 
use  of  the  coaxial  cable. 

The  third  available  system  for  trans- 


mission of  Tv  programs  is  the  use  of 
so-called  "balanced"  telephone  wires.  A 
network  of  such  wires  extends  across  the 
continent  operated  by  the  Bell  System. 
Over  moderate  distances  of  from  one  to 
two  miles,  these  telephone  wires  may  be 
adapted  to  the  purpose  of  Tv  transmis- 
sion. They  thus  are  useful  for  intracity 
transmission,  including  remote  pickup, 
STL,  and  possibly  as  the  basis  for  a 
multiple-addressee  system.  The  telephone 
wires  may  also  prove  to  be  the  most  eco- 
nomical method  for  distribution  of  thea- 
ter Tv  sound. 

Use  of  Radio  Frequencies 

As  we  have  seen,  radio  frequencies 
may  be  expected  to  constitute  an  integral 
part  of  a  theater  Tv  system  under  present 
conditions.  Remote  pickups  of  sports  and 
news  events  are  dependent  upon  micro- 
wave frequencies,  since  only  by  use  of 
radio  relay  can  theater  Tv  pickup  units 
get  the  necessary  mobility  and  flexibility. 

Multiple-addressee  systems  for  simul- 
taneous distribution  of  programs  to  nu- 
merous theaters  could  use  coaxial  cables 
or  even  paired  telephone  wires;  but  there 
is  no  assurance  that  the  telephone  com- 
pany will  be  in  a  position  to  furnish 
these  services,  or  that  the  rates  for  the 
service  would  be  within  reach  of  poten- 
tial theater  Tv  systems.  It  is  also  possible 
that  theater  Tv  will  consider  the  estab- 
lishment of  an  intercity  relay  system 
using  radio. 


Under  the  Communications  Act.  the 
use  of  radio  frequencies  by  theater  Tv  or 
by  any  other  non-governmental  service 
must  be  preceded  first  by  the  allocation 
by  the  FCC  of  a  frequency  band  or  bands 
for  the  use  of  theater  Tv ;  second,  by  the 
promulgation  by  the  FCC  of  rules  and 
regulations  governing  the  assignment  and 
use  of  the  allocated  frequencies  by  indi- 
viduals or  organizations  within  the  serv- 
ice; and  third,  by  the  assignment  by  the 
FCC  of  the  frequencies  within  the  gen- 
eral band  allocated  to  theater  Tv  licensees 
upon  proper  application. 

First  Hurdle  Not  Surmounted 

Theater  Tv  has  never  jumped  the  first 
hurdle.  It  has  never  obtained  an  alloca- 
tion of  frequencies  by  the  FCC  for  other 
than   experimental  use. 

At  the  present  time,  no  frequencies  are 
even  available  under  the  FCC  allocation 
table  and  rules  for  experimentation  by 
theater  Tv,  except  the  475-  to  890-mega- 
cycle  band  (ultrahigh-frequency) ,  which 
is  earmarked  for  Tv  broadcasting,  and 
the  frequency  bands  16,000  to  18,000 
megacycles  and  26,000  to  30,000  mega- 
cycles, for  which  no  equipment  is  avail- 
able for  the  purpose  of  theater  Tv  relays. 

The  five  theater  Tv  authorizations  now 
in  existence  (four  of  which  are  held  by 
Paramount  and  one  by  20th  Century- 
Fox)  are  solely  experimental,  special 
(Continued  on  page  37) 


A  Novel  All-Purpose  Pocket 
Marker  For  Film  Use 

By  ALEX  WEISS 
IA  Local  Union  160,  Cleveland 

Since  multiple-reel  pictures  came  into 
general  use,  the  careful  projectionist 
found  it  helpful  to  mark  his  films  with 
proper  titles,  reel  numbers,  start  marks, 
reel  end,  etc.  For  lack  of  anything  better, 
the  China  or  wax  pencil  was  generally 
used  for  this  purpose.  However,  due  to 
its  characteristic  messiness  and  habit  of 
smearing  over  the  film,  the  projectionist's 
hands,  and  even  over  the  projector  parts 
the  wax  pencil  soon  lost  favor,  although 
many  projectionists  are  even  now  using  it. 

During  the  past  several  years  paints  of 
various  kind,  lacquers,  and  even  nail 
polish  have  been  used  for  marking  films. 
While  this  method  proved  far  better  than 
the  wax  pencil,  it  left  a  lot  to  be  desired 
and  definitely  pointed  to  the  need  for 
a  simple,  efficient  and  inexpensive  mark- 
ing device. 


FELT  TIP  NOSE   BARREL  WASHES 
.  PH-9   nw,      PK^ 


BARREL 
,  PK-1 


FILM   POCKET   MARKER 

Can't    leak,    sweat    or    flood.    Patented    valve 

action    feeds    ink    to    felt    tip    when    pressed 

downward. 


Diligent  search  revealed  a  number  of 
such  markers  in  wide  use  by  various  in- 
dustries. While  the  markers  themselves 
were  acceptable,  the  regular  inks  and 
colors  as  used  by  the  other  industries 
were  not  suitable  for  use  on  films. 

Special  Ink  Solves  Problem 

This  problem  has  been  overcome  by 
the  development  of  a  special  ink  for  use 
on  film,  making  possible  an  ideal  marker 
that  is  always  ready  for  instant  use.  Films 
may  be  marked  quickly  and  neatly.  The 
marks  dry  very  fast,  will  not  buckle 
either  nitrate  or  acetate  film  stock,  and 
are  permanent.  The  marker,  shown  here, 
will  not  smear,  fade  or  peel  during  ordi- 
nary use.  Yet,  whenever  necessary,  the 
marks  can  be  readily  wiped  off  with  a 
few  drops  of  film  cement. 

The  marker  is  made  of  solid  aluminum 
in  the  shape  of  a  conventional  fountain 
pen  with  a  felt  tip  and  should  last  for 
many  years.  It  holds  ^  ounce  of  the 
special  ink,  enough  for  weeks  of  use 
before  refilling.  Ink  is  supplied  in  either 
red  or  bright  yellow.  The  unit  is  fully 
guaranteed. 

The  user  is  strongly  cautioned  never 
to  use  paint,  lacquer,  or  other  inks  ex- 
cept that  furnished  with  the  marker,  as, 
foreign  compounds  will  prevent  proper 
functioning  of  the  unit.  Address  the 
writer  at  2781  Hampshire  Road,  Cleve- 
land 6,  Ohio. 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


21 


IN  THE 

SPOTLIGHT 


By 

HARRY 

SHERMAN 


THIS  department  is  actually  a  barometer  of  craft  welfare,  because  it  reflects 

not  so  much  the  views  of  an  individual  as  it  does  the  constant  flow  of  helpful 

information  which  is  received  from  those  men  of  goodwill  who,  by  informing 

and  instructing  others,  are  giving  true  expression  to  craft  unity.    This  in  itself 

is  the  highest  form  of  brotherhood,  the  fundamental  basis  of  a  labor  union. 

We  can  only  express  our  thanks  in  cold  type;  but  at  this  Holiday  Season 
we  set  down  these  few  words  of  heartfelt  thanks  to  all  those  whose  unselfish 
devotion  to  the  principles  of  Unionism  and  brotherhood  have  made  it  possible 
for  us  to  be  the  medium  of  contact  between  a  group  of  men  who,  however 
separated  by  distance,  are  bound  together  in  a  common  unity — in  our  case,  the 
International  Alliance.  Labor  union,  yes;  but  something  more — and  that  some- 
thing is  the  fraternity  of  men  who  have  voluntarily  joined  together  in  the  full 
knowledge  that  only  in  this  way  can  they  serve  themselves  and  their  fellowmen. 


•  Wage  negotiations  for  Los  Angeles 
Local  150  were  successfully  concluded 
recently  and  contracts  with  the  major 
theater  groups  were  signed  calling  for 
10c  per  hour  wage  increase,  two  weeks' 
paid  vacations  and  other  benefits.  The 
new  contracts  are  retroactive  to  June  30 
last.  Carl  Cooper,  IA  vice-president,  in 
charge  of  negotiations,  was  ably  assisted 
by  Earl  Hamilton,  Charlie  Vencill,  Mag- 
nus Nielsen,  and  Rodney  Bacon,  of  Lo- 
cal 150. 

The  Local  officials  are  now  in  the 
midst  of  negotiations  with  the  indepen- 
dent theaters. 

•  Jake  Pries,  business  representative  of 
Local  225,  Atlanta,  Ga.,  for  many  years, 
resigned  from  office  recently  and  plans 
to  devote  more  time  to  his  personal  in- 
terests. Jake  has  been  employed  as  pro- 
jectionist at  the  Fox  Theater  for  the 
past  20  years. 

•  Mayor  Gordon  G.  Dunn,  of  Fresno, 
Calif.,  appointed  J.  G.  Viele,  of  Fresno 
Local  599,  a  member  of  the  Police  Advis- 
ory Commission.  Viele  was  one  of  the 
founders  of  the  Union  Post  No.  687, 
American  Legion. 

•  The  Legion  Cinema  Post  No.  561  (Los 
Angeles)  awarded  Roy  M.  Brewer,  presi- 
dent of  the  AF  of  L  Hollywood  Film 
Council  and  IA  West  Coast  representa- 
tive, with  an  American   Legion   citation 


for  his  work  against  un-American  activi- 
ties. 

•  Herbert  Aller,  secretary  and  business 
representative  of  Cameramen's  Local  659, 
Hollywood,  was  elected  president  of  the 
newly  organized  AF  of  L  Voters  League 
Club  in  the  15th  Congressional  District 
of  California.  Serving  as  vice-presidents 
in  the  various  Assembly  Districts  of  the 
League  Club  are  a  number  of  IA  men, 
namely:  Roy  M.  Brewer,  International 
representative;  Roy  Hostetter  and  James 
Tante,  Local  728;  Ted  Ellsworth,  Local 
705;  Robert  F.  Joseph,  Local  776,  and 
Emmett  H.  Zilles,  Local  44. 

•  Upon  completion  of  a  successful  year 
of  operation,  the  Chicago  Motion  Picture 
Operators  Beneficial  Association,  which 
provides  sick,  disability,  retirement,  death 
benefits,  and  vacations  for  the  members 
of  Local  110,  invested  part  of  its  surplus 


funds  in  the  purchase  of  $100,000  worth 
of  U.  S.  Government  bonds. 

Shown  here  at  the  moment  of  purchase 
are,  left  to  right,  George  Moore,  Labor 
Representative,  U.  S.  Treasury  Dept.; 
Clarence  Jalas,  secretary-treasurer,  and 
Gene  Atkinson,  business  manager,  of 
Local  110. 

•  In  a  recent  column  by  Sidney  Skolsky, 
the  widely  syndicated  columnist,  he  de- 
plored the  lack  of  experienced  camera- 
men in  television  studios.  Mr.  Skolsky 
evidently  is  not  privvy  to  what  goes  on 
"behind  the  scenes,"  for  then  he  would 
have  known  that  more  than  a  year  ago 
Herb  Aller,  business  representative  of 
Cameramen's  Local  659,  offered  the  serv- 
ices of  his  members  (many  of  whom  earn 
as  high  as  $1500  a  week),  to  the  tele 
studios  at  nominal  salaries.  His  offer  was 
rejected  with  the  flimsy  excuse  that  a 
"knowledge  of  electronics  was  preferred 
to  that  of  expert  camera  operation  and 
composition."  We  don't  know  what  the 
real  reason  was  for  the  rejection  of  Aller's 
generous  offer,  but  we  do  know  that  pres- 
ent-day tele  camera  work  leaves  room 
for  a  great  deal  of  improvement. 

•  The  40th  biennial  IA  Convention  will 
be  held  at  the  Masonic  Temple,  Detroit, 
Mich.,  the  week  commencing  August  14, 
1950. 

•  Michael  J.  Nugent,  recording-corres- 
ponding secretary  for  the  past  three  years 
of  Local  650,  Westchester  Co.,  N.  Y., 
has  been  elected  a  councilman  of  the 
city  of  Yonkers,  N.  Y.,  for  the  1950-51 
term.  Running  on  the  Democratic  ticket, 
Nugent  received  all-out  Labor  support, 
particularly  by  the  IA  Locals  in  West- 
chester. In  addition,  he  was  endorsed  by 
the  Liberal  Party  and  by  the  AFL-CIO 
Non-Partisan  League.  So  close  was  the 
election  in  this  predominantly  Repubb- 
can  community  that  the  results  were  not 
made  official  until  all  the  voting  machines 
were  re-tabulated. 

Nugent  represented  the  Westchester 
Federation  of  Labor  at  the  1949  New 
York  State  AF  of  L  Convention,  and  is 
treasurer  of  the  AFL-CIO  Non-Partisan 


22 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


Michael  J.   Nugent 

League.  He  has  been  a  projectionist  at 
the  RKO  Theatre,  Yonkers,  for  a  number 
of  years. 

Nice  going,  Mike,  not  only  because  we 
are  always  glad  to  see  one  of  our  fellows 
make  the  grade,  but  also  for  the  swell 
fight  you  waged   against  tough  odds. 

•  Willis  B.  Clarke,  59,  member  of  Local 
599,  Fresno,  Calif.,  died  several  weeks 
ago  after  a  six-months'  illness.  For  the 
past  32  years  he  worked  as  a  projection- 
ist in  various  theaters  in  Fresno,  and  took 
an  active  part  in  the  affairs  of  Local  599. 
Clarke  served  as  president  of  the  Local 
for  ten  years,  and  about  two  years  ago 
he  was  awarded  a  life  membership  card. 
A  well-known  radio  ham  operator,  he  was 


one  of  the  founders  of  the  R-9  Radio 
Club.  He  was  also  a  member  of  the 
Fresno   Radio  Association. 

•  We  regret  to  report  the  death  of  our 
good  friend,  William  T.  Madigan,  mem- 
ber of  Minneapobs  Local  219  and  former 
7th  IA  vice-president.  Bill  was  stricken 
with  a  fatal  heart  attack  at  his  home. 
He  was  born  in  Duluth,  Minn.,  62  years 
ago  and  had  made  his  home  in  Minne- 
apobs for  the  last  38  years.  Bill  was  one 
of  the  first  to  join  Local  219  when  its 
charter  was  granted  in  1911,  and  he 
served  several  terms  as  business  repre- 
sentative and  on  the  executive  board.  He 
worked  in  the  projection  room  of  the 
State  Theater  for  a  number  of  years 
until  illness  confined  him  to  his  home 
for  several  weeks  prior  to  his  death. 

Burial  was  at  the  Catholic  Cemetery 
in  Duluth,  with  the  following  members  of 
Local  219  acting  as  honorary  pallbearers: 
Jack  Lewis,  Wallace  Yutzy,  Sherman  Par- 
rish,  R.  A.  Peterson,  Earl  Smith,  Gerald 
Hoover,  Wood  Smith,  Ray  Gullickson, 
John  Kloster,  Frank  Rogers,  Charles  Feh- 
ling  and  Ray  Dailey.  Harry  B.  French, 
president  of  the  Minnesota  Amusement 
Co.,  was  also  a  pallbearer. 

Bill  is  survived  by  his  wife,  Charlotte; 
a  stepson,  Allen  W.  Harris,  member  of 
the  Local,  and  a  stepdaughter,  Florence 
Harris,  member  of  Local  F-31. 

•  Evidence  of  the  progressive  spirit  of 
Local  236  is  this  reproduction  of  the 
organization's  advertisement  which  ap- 
peared in  a   special  movie  edition   pub- 


£ 


euSon  6 


PROJECTIONISTS   LOCAL   NO.    173 
I.   A.   T.   S.   E. 


TORONTO,  ONT. 


CANADA 


*  *  * 


Ifcfit     ifeJj£0  •  •  * 

INTERNATIONAL  ALLIANCE  OF 

THEATRICAL  STAGE   EMPLOYEES  and 
MOVING  PICTURE  MACHINE  OPERATORS 

of  the 

UNITED  STATES  and  CANADA 

LOCAL  UNION  NO.  376 

SYRACUSE  NEW  YORK 


Congratulations 
And  Best  Wishes 

To 

ALL  THE  THEATRES 

In 

THE  BIRMINGHAM  DISTRICT 

From 

Moving  Picture 

Machine 

Operators  Union 

Local  No.  236 

For  Your  Next  1 6  MM.  Show 

Call  7-4570 

For  a  Competent  Operator 


lished  on  November  2nd  last  by  the 
Birmingham  (Alabama)  Post.  Note  the 
significant  reference  to  competency  in 
connection  with  16-mm  film  showings. 

•  The  100th  anniversary  of  the  birth  of 
the  late  Samuel  Gompers,  founder  and 
first  president  of  the  AF  of  L,  will  be 
observed  January  5  next  with  a  dinner 
at  the  Hotel  Statler,  in  Washington,  D.  C. 
AF  of  L  officials  are  completing  details 
for  this  centennial  observance,  which  is 
expected  to  number  President  Truman 
and  many  other  top  government  officials 
among  those  present.  IA  President  Walsh 
is  on  the  Formulating  Committee. 

•  William  P.  Covert,  2nd  IA  vice-presi- 
dent and  business  representative  of  To- 
ronto Local  173  is  on  the  sick  list.  He 
has  been  granted  a  leave  of  absence  from 
his  official  duties  with  full  pay.  We  hope 
that  this  much-needed  rest  will  put  Bill 
back  in  tip-top  shape  and  that  he  will  be 
able  to  resume  his  activities  very  soon. 

•  Elmer  Winegar,  treasurer  of  Buffalo 
Local  233  for  the  past  12  years,  acted  as 
chairman  of  the  vaudeville  quiz  show 
staged  last  month  at  the  Memorial  Audi- 
torium by  Ismailia  Temple  Shriners.  El- 
mer is  a  Past  Potentate  of  Ismailia  Tem- 
ple. 

•  The  25-30  Club  of  Greater  New  York 
held  a  dinner-dance  at  the  Hotel  New 
Yorker  last  month,  which  was  conceded 
to  be  one  of  the  most  successful  affairs 
ever  given  by  the  Club.  Many  out-of-town 
members  and  practically  the  entire  local 
membership  of  the  Club  attended. 

•  Recent  out-of-town  visitors  to  IP  offices: 
Sid  C.  Blande,  business  representative, 
Local  570,  Michigan  City,  Ind. ;  from 
Local  329,  Scranton,  Penna.,  came  John 
Corby,  secretary;  Edward  Friedman, 
president;  Percy  Carr,  business  repre- 
sentative; Donald  Ball.  Clayton  Leas, 
and  Edward  Pantle. 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


23 


French  Propose  21-mm  Film  Width  to  Supplant  16-mm 


FRENCH  film  technicians  are  vigor- 
ously advocating  change  in  film  size 
from  16-mm  to  21-mm  in  width,  according 
to  an  article  in  La  Cinematrographio 
Frangaise.  The  larger  size  would  have 
two  perforated  edges  carrying  double 
the  number  of  perforations  as  compared 
to  the  present  16-mm  size — that  is,  the 
film  would  be  perforated  to  a  pitch  simi- 
lar to  that  of  double-run  8-mm  film. 

Support  for  the  wider  gauge  film  is 
based  on  the  reasons  set  forth  in  the  fol- 
lowing excerpts  from  the  aforementioned 
article : 

"Since  the  appearance  of  sound  films,  and 
especially  since  the  adoption  of  16-mm  film 
as  a  sub-standard  size,  continual  criticism 
has  been  encountered  from  the  professionals. 
Il  was  soon  seen,  in  fact,  that  the  practical 
advantages  which  were  the  reasons  for  its 
adoption  were  largely  offset  by  technical 
limitations. 

Single  Row  of  Perforations  Decried 

"All  possible  improvements  have  been 
added,  but  the  major  cause  of  its  fragile 
nature  still  remains,  since  the  16-mm  film 
carries  only  one  row  of  perforations.  Hence, 
there  is  an  uneven  pull  and  frictional  con- 
tact with  the  sound  track  against  the  sur- 
faces which  are  essential  for  its  guidance 
through  the  apparatus. 

"If  one  insists  on  keeping  to  the  16-mm 
size,  then  it  is  certainly  impossible  to  add  a 


American   Standard   for   16-mm   sound   picture 

print    (ASA    Z22.41).    Sound    track    shown    is 

full-width,  variable-density  record. 


00S6t0.002    |N_      J\ 


|.473±0.05l  MM 


0.072  IN.  MAX,  0,070  IN,  MIN 


I.B29MM  MAX, 1.778  MM  MIN 


0.0581"'""'   IN. 


I.473IU-U"  MM 


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SOUND  RECORD 


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-(£_  SOUND  RECORD 


SCANNED  AREA 


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-<£_  SCANNED  AREA 


second  row  of  perforations,  since  the  width 
of  the  picture  (10.31-mm)  and  of  the  sound 
track    (2.15-mm)    cannot  be  reduced. 

"Taking  these  data  into  account  and  after 
tests  resulting  from  critical  expert  examina- 
tion of  worn  copies,  M.  Jean  Vivie,  Chief  of 
the  Controle  Technique  du  Cinema,  in  1944 
put  forward  a  studied  plan,  wherein  the  sub- 
standard film  size  should  be  altered  to  19-mm 
to  include  a  second  row  of  perforations.  This 
suggestion   in  no  way  modified  the  relative 


arrangements  of  16-mm  dimensions,  but  it 
placed  a  second  row  of  perforations  along- 
side the  sound  track. 

Smoother  film  Drive,  Longer  Life  Seen 

"By  this  means  the  film  drive  could  be 
made  symmetrical,  and  the  sound  track 
rested  no' longer  on  the  edges  of  the  guides. 
In  consequence,  a -longer  useful  film  life  and 
better  sound  reproduction  became  possible." 

Subsequent  extended  discussion  and 
further  experimentation  by  several  lead- 
ing French  technicians  resulted  in  a  final 
decision  in  favor  of  the  21-mm  width, 
since  with  this  slight  addition  over  the 
19-mm  minimum  it  became  possible  to 
extend  the  sound  track  somewhat  so  as 
to  equal  that  on  35-mm  film,  while  pro- 
viding a  larger  margin  between  the  track 
and  the  perforations. 

International  Standards  Aspect 

It  is  emphasized  in  the  article  that 
while  the  plan  involves  a  minimum  of 
necessary  alterations  to  various  units  oi 
equipment,  no  definite  steps  have  yet 
been  taken  in  this  direction  inasmuch  as 
the  proposal  for  the  new  gauge  has  hot 
yet  been  formally  presented  for  rati- 
fication. 

A  proposal  such  as  this  is,  of  course, 
very  definitely  a  matter  for  consideration 
by  the  International  Organization  for 
Standardization,  in  which  France  is  rep- 
resented by  a  very  active  group.  As  is 
well  known,  present  French  16-mm  stand- 


ifigS 


^Jo      Ljou     s^raffo 


men 


Merry  Christmas! 


^jror    ^Jhe      I lew      Ujc 


ear 


Continued  Prosperity! 


J.E.McAULEY  MFG. CD. 

552-554    WEST   ADAMS    STREET 
CHICAGO   6.  ILLINOIS 


24 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


ards  agree  substantially  with  American 
standards. 

There  has  been  no  meeting  of  the 
I.O.S.  since  the  war,  but  it  is  likely  that 
a  session  will  be  called  for  1950,  prob- 
ably in  Geneva,  Switzerland.  Incident- 
ally, the  SMPE  acts  as  the  Secretariat 
for  Motion  Pictures  in  the  I.O.S.  and 
undoubtedly  would  have  more  than  a 
passing  interest  in  the  aforementioned 
French  proposals  for  a  change  in  stand- 
ards. IP  is,  therefore,  inviting  the  atten- 
tion of  the  SMPE  to  this  matter. 


NEWS    PROJECTIONS 

Jottings  of  happenings  which,  while  mostly  of 

a  non-technical  nature,  have  a  bearing   upon 

general  industry  welfare  and  progress. 

FORECASTING  strong  national  news- 
■  paper  pressure  for  the  repeal  of  all 
wartime  excise  taxes  was  a  recent  lead 
editorial  in  the  New  York  World  Tele- 
gram, bellwether  unit  of  the  powerful 
Scripps-Howard  chain,  which  charged 
that  such  taxes  were  seriously  retarding 
business,  particularly  the  motion  picture 
industry.  .  .  .  United  Artists  has  adopted 
a  profit-sharing  plan  for  district  and 
branch  managers  and  other  sales  person- 
nel. Plan  is  based  on  a  percentage  of 
increase  of  1950  sales  over  those  of  this 
year.  .  .  .  Word  is  that  the  FCC  is  about 
ready  to  hold  a  full-dress  hearing  on  a 
national  theater  Tv  set-up.  .  .  .  Tv  sets 
are  at  the  very  top  of  the  Xmas  best-seller 
list,  a  nation-wide  store  survey  shows. 
.  .  .  Stiff  distributor  percentage  terms 
for  some  of  the  "big"  pictures  are  forcing 
upped  admission  prices  in  many  situa- 
tions. 

Net  earnings  of  20th  Century-Fox  and 
subsidiaries  for  this  year  are  estimated 
at  $8,200,000,  a  drop  of  about  $800,000 
from  last  year.  .  .  .  Motiograph's  new  and 
elaborate  brochure  on  drive-in  theaters 
is  available  for  the  asking.  Address  4431 
West  Lake  St.,  Chicago.  .  More  than 
500  people  were  turned  away  from  the 
Pilgrim  Theater,  Boston,  when  the  Notre 
Dame-So.  California  football  game  was 
televised  in  large-screen  fashion.  .  .  .  Mo- 
tion picture  salesman  got  a  $10  weekly 
pay  hike  under  the  terms  of  their  new 
deal  with  distributors.  .  .  .  Loew's, 
Warners  and  20  Century-Fox  still  tussling 
with  the  Dept.  of  Justice  in  an  effort  to 
avoid  divorcement  of  production  and  the- 
ater chains.  .  .  .  U.  S.  Treasury  reports 
$3  million  increase  in  admission  tax  take 
for  October  of  this  year  over  same  month 
in  1948. 

Republic  Pictures  has  a  robust  back- 


^^^^^s^as^s^^ss^ss^s^^s^^j^s^^j^s^^^^^^^s^s^^s^^^^^^^; 


(Smtutga  mxb  j&tzt  Wxb^b 


to  all  our  friends 


ESSANNAY  ELECTRIC  MFG.  CO 


1438  NORTH  CLARK  STREET 
CHICAGO  10,  ILLINOIS 


log  of  21  feature  films.  .  .  .  Columbia 
Pictures  earned  $500,000  in  third  quar- 
ter of  this  year,  as  compared  with  a 
$23,000  loss  for  similar  period  in  1948. 
...  J.  Arthur  Rank,  top  British  film 
producer,  said  to  be  brewing  a  deal  to- 
make  70  feature  films  available  for 
American  Tv  stations.  .  .  .  Magnetic  re- 
cording, utilizing  a  coating  of  metallic 
powder  on  the  film  base,  is  speeding 
Hollywood  production  and  cutting  costs 
sharply.  ...  58  of  81  towns  in  Penna. 
voted  during  the  recent  election  in  favor 
of  Sunday  movies. 

DuMont  had  a  profit  of  $1,676,000  for 
the  40  weeks  ending  Oct  9.  .  .  .  Motion 
picture  theater  attendance  nationally  is 
estimated  by  the  Wall  Street  Journal  to 
have  fallen  off  10%  from  last  year's  mark. 
...  20  Century-Fox  expects  to  increase 
its  print  order  by  50  for  its  more  im- 
portant features.  Theater  men  have  been 
complaining  bitterly  about  the  print 
shortage  and  the  physical  condition  of 
those  prints  available. 

Some  Observations  on  the 
Perception  of  Color* 

WHEN  the  eye  is  exposed  for  a  long 
time  to  a  scene  illuminated,  for 
example,  by  an  ordinary  incandescent 
light,  the  average  color  entering  the  eye 
is  roughly  equivalent  to  that  of  the  light 
source  itself,  that  is,  as  the  eye  looks 
first  at  one  and  then  another  of  the  ob- 
jects the  average  quality  of  the  light  seen 

Reprinted  by  permission  from  AN  INTRO- 
DUCTION TO  COLOR,  hy  R.  M.  Evans;  pub- 
lished by  John  Wiley  &  Sons,  Inc.   (N.  Y.  City). 


tends  to  approach  that  of  the  incandes- 
cent light. 

Since  such  a  light  is  weakest  in  the 
blue  end  of  the  spectrum  and  next  weaker 
in  the  green  relative  to  the  red,  the  eye 
tends  to  become  quite  sensitive  to  blue, 
somewhat  less  so  to  green,  and  least  to 
red,  and  all  stimuli  are  seen  with  the  eye 
in  this  condition  because  the  long  expo- 
sure makes  recovery  slow. 

'Color  Constantcy'  of  the  Eye 

This  eye-sensitivity  distribution,  how- 
ever, is  opposite  to  the  energy  distribu- 
tion of  the  source.  Accordingly,  a  non- 
selective surface  illuminated  by  this  qual- 
ity of  light  tends  to  be  seen  as  white,  i.e., 
it  gives  the  same  output  to  the  brain  from 
the  receptors  as  daylight.  Furthermore, 
all  normal  colors  will  tend  toward  their 
appearance  in  daylight  because  the  eye 
tends  to  compensate  for  the  deficiencies 
of  the  source  by  its  own  sensitivity 
readjustments. 

This  phenomenon  is  known  among 
psychologists  as  "color  constancy,"  be- 
cause it  tends  to  make  the  color  of  objects 
constant  regardless  of  the  energy  distri- 
bution of  the  general  illuminant  in  the 
scene.  Obviously,  it  is  of  very  great  im- 
portance in  daily  life  since  it  tends  to 
make  color  a  property  of  the  object  rather 
than  the  variable  it  would  be  if  the  re- 
ceptor sensitivities  were  fixed.  A  white 
paper  illuminated  by  artificial  light 
would  be  very  yellow  indeed  if  the  eye 
sensitivities  did  not  readjust  to  the  situ- 
ation.— Chapter  VIII,  "The  Visual  Vari- 
ables of  Color." 

Quirks  in  Viewing  Process 

The  average,  normal,  non-color  con- 
scious observer  is  motivated  primarily  by 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


25 


a  desire  to  observe  the  properties  of 
objects.  If  the  writer  may  be  forgiven 
the  remark,  this  applies  also  in  a  slightly 
different  sense  to  artists  and  others  who 
strive  to  "see"  nature  in  one  way  or 
another. 

Viewing  of  a  color  in  a  particular  situ- 
ation is,  at  best,  a  peculiar  mixture  of 
attention,  intention,  and  memory.  Depend- 
ing on  the  particular  background  of  the 
individual,  one  or  the  other  of  these  will 
come  to  the  fore,  and  with  results  that 
are  well-nigh  unpredictable  without  an 
introspective  report  from  the  individual 
concerned. 

A  naive  observer  will  report  a  leaf  as 
green  when  the  light  reaching  his  eye 
must  be  pure  blue — he  hasn't  looked. 
An  artist  will  report  that  the  distant  view 
seen  through  green  foliage  is  pink — he 
has  looked  for  color,  and  his  adaptation 
to  the  foliage  has  produced  pink  from 
the  distant  haze.  The  interested  layman 
will  report  that  the  shadow  side  of  the 
box  is  the  same  yellow  as  the  illuminated 
side  because  he  has  looked  for  surface 
qualities.  All  are  right  and  entitled  to 
their  judgments.  Color  is  what  you  do 
see,  not  what  you  should  see." — Chapter 
XI,  "Color  Perception." 

Accurate  Color  Representation 

Photography  from  the  standpoint  of 
the  color  expert  *  *  *  is  somewhat  dif- 
ferent from  the  commonly  held  view  that 


*?8W»?Sr*3iSre?$r«^^ 


^jrraternai 


it    LjreetinaA 

TREASURERS  AND  TICKET  SELLERS 

LOCAL  UNION  NO.  751 

I.  A.  T.  S.  E. 

NEW  YORK,  N.  Y. 


it  accurately  and  correctly  reproduces 
anything  placed  before  it.  To  do  so  it  is 
necessary  that  the  visual  situation  be 
analyzed  clearly  by  the  photographer 
and  that  such  determinants  of  the  final 
perception  as  will  be  missing  in  the  final 
reproduction   be    supplied   by   distortion 


of  the  colors  and  brightness  of  the  scene 
itself. 

The  effects  involved  and  the  correc- 
tions that  must  be  applied  are  often 
larger  than  the  defects  of  reproduction 
in  the  better  of  the  existing  processes. 
— Chapter  XIX,  "Color  in  Photography." 


A  Glossary  of  Tv  Terms 

Here  is  a  list  of  terms  which  are  be- 
coming increasingly  common  in  the 
field  of  television  and  more  particularly 
in  color  Tv.  Tenative  definitions  are 
suggested  for  some  of  the  newer  terms. 

Adaptability.  A  feature  of  a  pro- 
posed color  Tv  transmission  system 
which  makes  its  use  possible  with  exist- 
ing receivers  to  obtain  monochrome — or 
color-pictures  only. 


«a»«WWiBSfi»«ffl8f»^^ 


NATIONAL  CARBON  COMPANY,  INC. 

30  EAST  42nd  STREET 
NEW  YORK  17,  N.  Y. 


Adder.  An  electronic  device  in  which 
electrical  signals  are  combined  to  form 
a  composite  signal.  Example:  com- 
bining samples  of  colors  of  the  televised 
scene  with  the  horizontal  sync  pulses. 

Additive  Color.  A  system  which  com- 
bines two  colors  to  form  a  third. 

Compatibility.  Ability  of  color  Tv 
transmission  system  to  provide  color 
service  for  modified  or  special  color  re- 
ceivers and  still  produce  monochrome 
pictures  on  existing  receivers  without 
modification. 

A  term  used  to  designate  electrically 
the  average  brightness  of  the  scene 
being  televised,  as  distinguished  from 
the  extreme  highlights  and  shadows. 

Dichroic  Mirror.  A  glass  surface 
treated  with  metallic  salts  which  ex- 
hibits the  property  of  reflecting  only 
one  color  and  absorbing  all  others. 

Dot  Interlacing.  A  method  of  placing 
dots  of  colors  on  a  Tv  screen  to  form 
the  complete  picture.  During  the  first 
scanning  of  each  color,  the  dots  are 
separated  by  approximately  their  own 
width,  and  on  the  following  scan  of  the 
same  color,  the  dots  are  placed  to  fill 
the   spaces  in  between. 

Electronic  Commutator.  A  switching 
arrangement  composed  of  electron 
tubes  and  circuits  used  to  connect  cir- 
cuits in  rapid  succession.  At  the  color 
Tv  transmitter,  the  commutator  sam- 
ples each  of  three  colors  in  a  specified 
order.  At  the  receiver,  the  commutator 
routes  the  three  color  signals  in  proper 
order  to  three  kinescopes. 

Field.  The  partial  image  which  re- 
sults from  a  single  scanning  of  green, 
red  and  blue  lines  from  top  to  bottom 
of  a  picture. 

Line  Interlacing.  The  standard  sys- 
tem of  picture  scanning  in  which  odd- 
numbered  lines  are  scanned  as  the  first 
field  and  even-numbered  lines  being 
scanned  as  the  second. 

Mixed-High  Frequencies.  The  por- 
tion of  the  Tv  color  signal  which  car- 


26 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


SrgffSr<5%rgffSrg^ 


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CENTURY  PROJECTOR  CORPORATION 


NEW  YORK,  N.  Y. 


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Dispenser  developed  by  Fisher  Mfg.  Co , 
Rochester,  makers  of  Ethyloid  film  cement. 
Instead  of  the  usual  brush,  a  metal  applicator 
having  an  interchangeable  felt  end  is  used 
to  supply  an  even  flow  of  cement.  Unit  is 
suitable  for  any  cement  which  does  not  congeal 
upon  exposure  to  air. 


ries  the  finer  (higher  frequencies)  de- 
tails of  the  transmitted  image. 

Picture  Dot.  The  basic — or  picture 
element — area  of  each  color  pulse.  In 
the  RCA  color  system,  there  are  3,800,- 
000  pulses  for  each  of  the  three  prim- 
ary colors  every  second. 

Reflective  Optics.  A  system  in  which 
the  rays  of  light  are  reflected  as  in  the 
Schmidt  system  of  projection. 

Refractive  Optics.  An  optical  system 
in  which  the  light  focusing  is  per- 
formed by  a  lens  through  which  the 
rays  pass. 

Samp'ing  Pulse  Generator.    A  circuit, 


controlled  by  horizontal  sync  pulses, 
which  in  turn  produces  the  timed  pulses 
needed  to  actuate  the  electronic  com- 
mutator. 

Sequential  Systems.  A  system  in 
which  the  colors  are  transmitted  one 
after  the  other  and  which  depends  on 
eye  retention  and  picture  tube  storage 
to  combine  them.  Is  used  for  line,  dot, 
and  field  sequential  operation  in  which 
the  respective  elements  are  produced 
sequentially. 

Simultaneous  Transmision.  A  system 
in  which  the  primary  colors  are  trans- 
mitted at  the  same  instant  and  are 
superimposed  one  over  the  other  at  the 
receiver. 

Subtractive  Color.  A  system  which 
subtracts  two  colors  from  white  light 
and  leaves  the  required  color. 

Time  Multiplex.  Successive  trans- 
mission of  pulse  samples  of  each  of 
several  signals. 


Srtssrassrt^Sr^^ 


Brnzttriz  (SmtttujH 


from 


M.  P.  M.  O.    LOCAL    NO.   650 

Westchester  County,  N.  Y. 


*  *  * 

(grating  ani  fest  HtBljeB 
PROJECTIONISTS  LOCAL  UNION  NO.  407 

SAN  ANTONIO,  TEXAS 

*  *  * 


How  Social  Security  Works 

What  happens  to  the  money  you  pay 
for  old-age  and  survivors  insurance? 
From  each  dollar  of  your  wages  (up  to 
$3,000  a  year)  l1/^  cents  (commencing 
January  1,  1950)  is  deducted  for  old- 
age  and  survivors  insurance.  Your  em- 
ployer matches  your  payment,  penny  for 
penny.  This  money  goes  to  the  old-age 
and  survivors  insurance  trust  fund. 

Some  of  the  money  in  the  Trust  Fund 
is  used  to  pay  current  monthly  benefits 
to  retired  workers  and  their  families  and 
to  families  of  workers  who  died.  More 
than  $50,000,000  in  benefits  is  paid  to 
about  2x/2  million  persons  every  month. 
A  small  part  (about  2%  of  receipts) 
pays  the  cost  of  operating  the  old  age 
and  survivors  insurance  program.  The 
rest  of  the  money  is  invested  in  Govern- 
ment bonds  as  a  reserve  to  help  pay  for 
future  benefits. 

Remember:  benefits  are  not  paid  auto- 
matically. A  claim  must  be  filed.  Fur- 
ther information  may  be  obtained  from 
any  local  Social  Security  office. 


Kodak  Earnings,  Wage  Dividend 

Eastman  Kodak's  earnings  for  three 
quarters  of  1949  were  about  17%  below 
earnings  for  the  same  period  in  1948. 
Sales  for  the  three  quarters  in  1949  were 
down  about  2.4%  from  the  same  period 
last  year. 

Net  earnings  during  the  three  quarters 
were  $35,130,264.  or  $2.68  per  common 
share.  This  compared  with  $42,501,249, 
or  $3.41  a  share,  for  the  corresponding 
time  in  1948.  Sales  were  $290,421,476, 
against  $297,546,670  in  the  1948  period. 
Kodak  has  55,000  shareholders. 

The  company's  directors  voted  an  em- 
ployee wage  dividend  estimated  at  $15,- 
500,000,  for  about  48.000  employees  in 
the  Western  Hemisphere.  The  wage  divi- 
dend is  the  largest  total  amount  in  the 
38-year  history  of  the  plan  at  Kodak, 
while  the  rate  of  payment  is  the  highest 
since  the  present  formula  became  effect- 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


27 


ive  in  1928.  Eligible  employees  will  re- 
ceive $25  for  each  $1000  earned  at  Kodak 
during  1945  through  1949. 


Neumade   Products'   New  Quarters 

Neumade  Products  Corp.  has  opened  new 
and  more  expansive  quarters  at  330  West 
42nd  St.,  New  York  City,  18.  Located  in 
a  modern  office  building,  it  was  possible  to 
effect  a  consolidation  of  business,  design  and 
engineering  departments,  which  are  con- 
stantly developing  new  equipment  for  the 
motion  picture,  micro-recording  and  televi- 
sion fields. 

Oscar  Neu,  president  of  Neumade  (and 
also  president  of  the  Theater  Equipment  and 
Supply  Manufacturers  Assoc.)  extends  a 
cordial  invitation  to  all  film  people  to  visit 
the  new  quarters.. 


(te?tttt0*s  attft  Uwt  Mtsljw  far  1350 

PROJECTIONISTS  LOCAL  NO.  249 
Dallas,  Texas 


Safety  Film  for  Canadian  Pics 

A  limited  amount  of  the  new  Eastman 
safety  stock  has  been  made  available  for 
the  first  time  by  Canadian  Kodak  for  the 
production  there  of  35-mm  features  and 
shorts,  all  such  film  in  the  past  having  been 
restricted  for  16-mm  use.  A  gradual  in- 
crease in  the  quantity  of  this  stock  available 
for  Canadian  use  is  forecast. 


George  Eastman — 

Father  of  Modern  Photography 

On  the  occasion  of  the  opening  of  the  George  Eastman  House,  now  the 
repository  of  the  outstanding  collection  of  photographic  memorablia  in 
the  world,  Dr.  C.  E.  K.  Mees,  Director  of  Research  for  Eastman  Kodak 
Co.,  made  the  dedicatory  address.  Excerpts  from  this  address  consti- 
tute an  important  contribution  to  the  history  of  the  photographic  art. 


R.  H.  Coffin  New  RCA  Victor  Ad  Head 

Ralston  H.  Coffin  on  December  1  assumed 
his  new  post  as  director  of  advertising  for 
the  Victor  Division,  Radio  Corporation  of 
America.  During  his  19  years  association 
with  many  important  national  advertising 
accounts,  Mr.  Coffin  was  prominently  identi- 
fied with  the  mass  distribution  of  consumer 
products.  In  his  new  post  he  will  co-ordinate 
and  administer  RCA  Victor's  extensive  ad- 
vertising  activities. 


IN  1877  George  Eastman,  23  years  old 
and  employed  as  a  bookkeeper  in  the 
Rochester  Savings  Bank,  contemplated 
a  visit  to  Santo  Domingo.  A  friend  sug- 
gested that  he  should  learn  to  take 
photographs  so  that  he  could  make  a 
record  of  his  trip.  He  didn't  make  the 
trip;  but  he  bought  the  necessary  ap- 
paratus and  arranged  with  a  local  por- 
trait photographer  to  teach  him  to  make 
photographs. 

Photographs   at  that  time  were  made 
by  what  was  known  as  the  "wet  collodion 


Greetings  and  Best  Wishes 

for  a 

ifappg  Iffllftag 

ALBERT   F.   RYDE 
Business  Representative 

MOVING  PICTURE  PROJECTIONISTS 
LOCAL  No.  233,  I.  A.  T.  S.  E. 

Bnffulo,   N.   Y. 


process."  Glass  plates  were  coated  with 
a  layer  of  collodion  made  by  dissolving 
nitrocotton  in  a  mixture  of  ether  and 
alcohol  containing  some  bromides  and 
iodides. 

The  plate  was  made  sensitive  to  light 
by  dipping  it  into  a  bath  of  silver  nitrate 
solution,  and  exposed  in  the  camera 
while  still  wet,  with  a  piece  of  blotting 
paper  in  the  bottom  of  the  holder  to 
catch  the  solution  as  it  drained  off.  Then 
it  had  to  be  developed  at  once  while 
still  wet. 

Tents  Served  as  Darkrooms; 
Homemade  Emulsions 

This  made  it  necessary  for  the  pho- 
tographer to  carry  a  tent  around  with 
him  to  act  as  a  darkroom  for  preparing 
and  developing  the  plate. 

Eastman  became  interested  in  the  ac- 
counts appearing  in  the  British  photo- 
graphic papers  of  the  making  of  gelatin 
emulsions.  The  British  Journal  of  Pho- 
tography, particularly,  was  publishing 
articles  from  enthusiastic  amateur  pho- 
tographers who  were  making  their  own 
emulsions  and  coating  plates  which 
could  be  used  dry  instead  of  the  wet 
plates.  The  use  of  gelatin  for  making 
photographic  emulsions  had  been  sug- 
gested by  Maddox  in  1873. 

In  1878  the  aforementioned  Journal 
reported  that  Charles  Bennett  had  ex- 
hibited a  number  of  photographs,  one 
of  which  was  an  instantaneous  view  of 
a  boat  on  the  river  taken  in  approxi- 
mately l/20th  second.  Eastman  said 
that  it  was  the  remarkable  instantane- 
ous photographs  taken  by  Bennett,  ex- 
hibited in  London,  which  impressed  him 
(Continued  on  page  41) 


28 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


LETTERS    TO    THE    EDI 


To  the  Editor  of  IP: 

We  note  in  the  Letters  to  the  Editor 
column  of  your  publication  for  November 
(p.  17)  a  communication  relating  to  the 
Western  Union  Telcoarc. 

The  information  given  there  is  correct,  ex- 
cept for  one  statement  which  we  would  like 
to  have  revised  somewhat — that  referring 
to  the  Telcoarc  electrodes  being  "warranted 
by  Western  Union  to  operate  continuously 
for  37  hours." 

Your  readers  will  understand,  of  course, 
that  the  life  of  these  electrodes  are,  like 
any  other  arc,  dependent  upon  the  wattage 
at  which  they  are  operated.  A  table  pub- 
lished by  us  recently  shows,  for  example, 
that  when  operated  at  300  watts  the  Telco- 
arc electrodes  have  an  approximate  life  of 
30  hours;  while  if  they  are  operated  at  1000 
watts,  the  approximate  life  is  reduced  sharply 
— sometimes  by  as  much  as  four-fifths. 

We  congratulate  you  upon  the  very  clear 
exposition  of  the  principles  of  operation  of 
the  Telcoarc,  and  we  know  that  you,  no 
less  than  ourselves,  would  desire  that  the 
record  be  kept  straight  in  terms  of  the 
foregoing  statement. 

W.  D.  Buckingham 
The  Western  Union  Telegraph  Company 

To  the  Editor  of  IP: 

In  the  process  of  editing  my  article,  "Fire 


Extinguishers  in  Projection  Rooms,"  which 
appeared  in  your  October  issue,  p.  12,  you 
write  into  the  story  certain  implications 
which  did  not  appear  in  my  original  version. 
For  example,  I  don't  recall  having  used  the 
phrase  referring  to  "dilatory  inspectors  and 
exhibitors,"  which  I  assume  you  added  to  the 
story  in  the  process  of  suggesting  a  course  of 
action   by   projectionists. 

My  point  was  a  simple  one:  if  these  CO., 
bottle  extinguishers  constitute  a  hazard,  then 
our  people  should  waste  no  time  in  banish- 
ing them  from  projection  rooms.  The  fact 
that  Mr.  Robert  A.  Mitchell,  in  commenting 
upon  my  article,  didn't  see  fit  to  go  all  the 
way  down  the  road  with  me  is  o.k.  with  me. 
The  rather  extensive  editing  job  done,  how- 
ever, and  the  insertion  among  my  remarks 
of  statements  which  I  did  not  make,  is  quite 
something  else  again. 

We  seem  to  be  in  agreement  on  one  point, 
and  that  is  that  the  best  way  to  handle  a 
projection  room  fire  is  to  get  out  of  the  room 
— but  fast. 

George  R.  Stewart 
IA  Local  Union  150,  Los  Angeles 

Our  apologies  to  Mr.  Stewart.  In  sug- 
gesting a  course  of  action  for  projection- 
ists we  were  a  bit  on  the  over-zealous 
side.    Sorry. — Ed. 


Klondike  Gold  Rush  Days,  Old-Time  Movies  Recalled 

By  OTTO  NORDLING 

Apprentice  Member,  IA  Local  257,  Ottawa,  Canada 


VISITING  in  New  York  recently,  I 
was  shown  a  reel  of  film  that  holds 
6000  feet  of  film,  and  this  reminded  me 
that  this  much  footage  would  be  a  com- 
plete show  during  my  "silent"  projec- 
tionist days  in  the  Far  North,  the  fabu- 
lous Yukon  territory  of  Alaska,  more 
years  ago  than  I  care  to  remember — the 
land  of  the  famous  Klondike  gold  rush, 
Klondike  Kate,  Klondike  Mike  Mahoney, 
Alex  Pantages,  and  of  the  poet  who 
immortalized  that  Territory,  Robert 
Service. 

The  Dawson  Family  Theater  in  the 
Yukon  was  one  of  those  unbelievable 
places  where  things  happened  that  just 
couldn't  be — but  were.  Saturday  night's 
show  was  repeated  on  Monday  night  (50 
and  75  cents  admission),  but  the  other 
nights  of  the  week  were  scaled  at  25 
and  50  cents. 

It  should  be  understood,  of  course,  that 
films  could  be  shipped  in  only  during 
the  Summer  months  when  the  river  was 
free  of  ice  and  therefore  navigable.  The 
Winter's  supply  would  be  shipped  in 
from  September   10  to  October  1;   they 


would  be  returned  to  the  distributor  in 
Vancouver  the  following  June.  By  the 
time  Spring  rolled  around  the  various 
pictures  would  have  been  shown  over 
and  over  again. 

Keystone  Cops,  et  al 

Those  were  the  exciting  days  of  the 
Keystone  Cops,  Fatty  Arbuckle,  Harold 
Lloyd,  Pearl  White  (the  "Perils  of  Paul- 
ine") ;  Ruth  Roland.  Warner  Oland,  then 
a  mere  stripling;  Mary  Miles  Minter. 
Rudolph  Valentino,  Francis  Ford,  Mary 
Pickford — why  go  on? — and  the  days, 
too,  of  such  thrilling  serials  as  "The 
Million-Dollar  Mystery,"  "The  Diamond 
From  the  Sky,"  "Hands  Up!"  and 
"Wolves  of  Kultur." 

Of  course,  if  the  temperature  dropped 
to  45  degrees  below  zero,  as  it  frequently 
did,  the  show  would  be  cancelled  and 
the  admission  money  refunded.  Wood 
retailed  at  $18  a  cord;  power  at  25  cents 
per  kilowatt  hour. 

My  duties  were  many  and  varied — 
stoking  the  furnace,  shovelling  snow, 
packing  in  the  wood    (so  many  cords  of 


it)  ;  taking  cash  at  the  door  (no  ticket 
office)  ;  changing  the  music  rolls  on  the 
Wurlitzer  electric  piano,  running  the  pro- 
jector (there  was  only  one) ,  and  various 
other  odd  chores. 

The  average  show  ran  to  7  reels,  and 
the  audience  was  always  kept  informed 
of  the  progress  of  the  entertainment  by 
the  conventional  means  of  slides — "End 
of  Part  1,"  "Part  2,"  "End  of  Part  2," 
etc.  The  feature  ran  to  about  5  reels, 
and  there  was  a  1-reel  comedy  and  a 
1-reel  news.  I  wonder  if  this  wasn't  a 
better-balanced  show  than  are  today's 
double-feature  bills? 

Come  Spring  the  populace  would  be 
well  informed  about  the  happenings  in 
the  world — the  same  news  had  run  so 
many  times  from  October  1  to  June  1. 
Of  course  we  made  out  slides — and  crude 
affairs  they  were:  "Ladies  Will  Please 
Remove  Their  Hats" — and  there  were 
the  inevitable  ads  for  the  local  cafe,  the 
butcher,  the  baker,  and  other  emporia. 

Fresh  Eggs — 2  Months  Old 

Some  idea  of  the  primitive  character 
of  life  in  the  Yukon  in  those  days  may  be 
had  from  one  of  our  ad  slides  which 
stated  that  "fresh  eggs  JUST  ARRIVED 
on  the  last  overland  stage" — meaning 
that  they  had  been  en  route  from  Van- 
couver for  only  two  months!  At  12 
years  of  age  I  felt  I  was  quite  an  im- 
portant  community    figure. 

During  the  Summer  months — 8  weeks 
of  continuous  daylight  for  24  hours  each 
day! — we  were  forced  to  cover  tightly 
all  the  windows  in  our  theater  so  as  to 
keep  out  the  daylight.  Friday  evenings 
was  the  big  night  for  the  kiddies,  all 
admitted  free,  and  Harold  Lloyd  was  the 
top  favorite.  Capacity  was  450,  but  the 
kids  sometimes  made  it  seem  that  we 
played  to  1000  or  more. 

The  Dawson  Family  Theater  also 
served  as  the  Athletic  Association  build- 
ing. This  building,  *ince  destroyed  by 
fire,  was  the  scene  of  practically  all  im- 
portant social  functions,  political  meet- 
ings and  the  like,  and  invariably  the 
evening  was  topped  off  by  a  dance,  even 
when    the    temperature    hovered    around 

Reproduction    of   the   author's   apprentice    pro- 
jectionist license  for  Ottawa,  Canada. 


ittWt 


m 


inn  ^irturr  "Annrrniirp" 
Prnfr^nnjgifi  t.\t, 


THIS  UCtNH  MUST  BE  POSTEB  IN  PROJECTION  ROOM 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


29 


50  below  zero!  The  seats?  They  were 
merely  picked  up  and  stacked  at  the 
side  of  the  hall. 

The  manager  and  owner  of  the  theater, 
Fred  H.  Elliott,  an  Englishman  who  went 
to  the  Klondike  during  the  gold  rush 
days,  is  once  again  back  in  the  mining 
business  and  still  looks  forward  to  strik- 
ing a  bonanza.  The  writer,  after  all  these 


years,  is  now  serving  his  apprenticeship 
as  a  projectionist  at  the  Imperial  Theater 
in  Ottawa,  Canada.  The  Province  of 
Ontario  requires  an  apprenticeship  pe- 
riod of  12  months. 

Dawson  City  now  has  a  modern  theater 
which  shows  the  very  latest  sound  pic- 
tures, now  that  they  have  an  air  service 
twice  weekly. 


The  Origins  of  the  'Magic  Lantern 


M 


The  third  and  final  instalment  of  an  article  which  traces  the  development  of  the  modern 
slide   projector   out  of   the   old    art   of   "mirror-writing,"   a    derivation    of   the    silhouette. 


By  J.  VOSKUIL 

Research   Chemist,  Geldermalsen,   Holland 

IT  is  again  Schott  who  tells  us  about 
this  lecture  in  his  "Magia  Optica"  (p. 
426)  and  in  spite  of  the  fact  that  he 
does  not  mention  the  use  of  slides, 
Tacquet  must  have  used  them,  as  it  is 
impossible  to  accept  the  fact  that  the 
pictures  were  painted  on  the  mirror  and 
wiped  out  again  during  the  lecture 
(Fig.  3,  /*).  Thus  Tacquet  must  have 
introduced  the  first  lantern  slides. 

All  elements  for  a  complete  slide  pro- 
jector now  were  present,  lacking  only 
the  mind  to  unite  them  into  a  whole. 
This  mind  proved  to  be  the  well-known 
Dutch  scientist  Huygens.  He  constructed 
a  complete  projector  with  a  condenser 
and  a  calculated  projection  objective. 
Moreover,  he  had  made  separate  slides 
(Fig.  3,  k). 

A  new  period  in  the  development  of 
the  projection  lantern  now  begins  in 
which  the  names  of  Walgensten,  De- 
chales,  Zahn,  Hooke,  and  Molyneux  must 
be  mentioned.  That  the  name  of  Huy- 
gens has  receded  into  the  background  is 
the  result  of  the  fact  that  afterwards  he 
felt  somewhat  ashamed  of  his  activities 
connected  with  the  projection  lantern. 
Gradually  the  charlatans  began  to 
frighten  the  public  with  this  instrument 
of  wonder,  quite  apart  from  the  drain 
on  their  purses.  Huygens  was  above  any 
form  of  charlatanry,  and  he  tried  to 
forget  the  "incident,"  as  he  called  it, 
as  soon  as  possible. 

A  final  word  about  Kircher's  "lanterna 
magica"  in  the  second  edition  of  the 
"Ars  Magna":  when  this  picture  was 
viewed  the  projection  lantern  had  already 
existed  for  ten  years  and  therefore  it  is 
certainly  incorrect  to  consider  the  device 
in  Fig.  1**  as  the  first  magic  lantern  and, 
concomitantly,  Kircher  as  its  inventor. 

At  the  utmost,  Kircher  discovered  the 
principle  of  optic  projection  when  he, 
more  or  less  by  chance,  used  a  lens  to 


t  J.  Soc.  M.  P.  En«.,  Dec.,  1948. 
*  IP  for  October,  p.  21. 

**  IP   for  August   1948,   p.   19. 


improve  the  art  of  mirror-writing.  In 
fact,  he  had  not  the  slightest  idea  of  the 
importance  of  his  "invention"  and  was 
not  able  to  develop  it  in  a  logical  and 
systematic  way. 

When,  for  instance,  he  writes  about  the 
clearness  with  which  the  projected  writ- 
ing can  be  seen,  he  claims  that,  with  the 
means  at  his  disposal,  a  sharp  image  is 
obtained  at  a  distance  of  500  feet:  "Thus, 
an  instrument  24  times  larger  would  give 
a  sharp  image  at  a  distance  24  times 
greater,  namely,  12,000  feet."  Of  course, 
there  would  be  "some  difficulties,"  and 
the  images  would  be  too  large  and  too 
faint,  but  many  improvements  could  be 
introduced,  as  for  instance,  by  "using 
more   concave  mirrors." 

In  which  way  this  had  to  be  performed 
Kircher  did  not  mention,  "as  time  to 
make  further  experiments  failed  him." 
However,  he  "recommended  his  idea  to 
other  scientists   for   further  reflections." 

Application  First  Consideration 

When  Huygens  had  finished  his  lantern 
in  1659,  one  of  his  acquaintances,  a  cer- 
tain Guisony,  wrote  him  a  letter  from 
Rome  (1660)  remarking  that  Kircher 
was  not  yet  very  familiar  with  the  "in- 
vention of  the  lantern.  .  .  .  The  good  old 
Kirkher  (Kircher)  is  performing  a  great 
number  of  tricks  with  his  magnet  in  the 
Collegium  Romanum,  but  if  he  had  the 
invention  of  the  lantern,  he  should 
frighten  the  Cardinals  with  ghosts  all 
the  time." 

According  to  this,  it  appears  that 
Kircher's  knowledge  about  "the  art  of 
light  and  shadow"  had  not  made  much 
progress  in  the  years  after  he  had  ex- 
perimented with  Schott  and  de  Sepi,  and 
that  the  application  of  the  magic  lantern 
— namely,  "frightening  the  Cardinals"- — 
was  nearer  to  his  heart  than  its  con- 
struction. 

Indeed,  if  we  have  a  critical  look  at 
Fig.  1,*  we  notice  that,  for  instance,  the 
objective  is  in  the  wrong  place,  and  ap- 
parently Kircher  had  Bettini's  art  in  his 
mind,  so  we  are  justified  in  concluding 
that  Huygens  in  1659,  Walgensten  in 
1660,  and  Dechales  in   1665,  with  their 


"lanterns"  were  nearer  the  goal  than 
Kircher  in  1671.  Kircher's  complaint  in 
the  second  edition  of  the  "Ars  Magna" 
that  "Walgensten  had  sold  copies  of  his 
lantern  at  high  prices  in  France  and 
Italy  to  many  prominent  people"  is 
therefore  unfounded. 

Painting  With  Light,  by  John  Alton, 
A.S.C.  190  pages,  292  illustrations  plus  in- 
serts in  full  color,  7%  x  10%  inches.  The 
Macmillan  Co.,  New  York.   $6. 

Light,  when  manipulated  by  skilled  hands, 
can  completely  change  the  character  of  all 
things  animate  and  inanimate,  can  create 
moods,  can  beautify  or  distort,  can  enrich 
or  flatten  a  scene,  and  can  impart  to  or  steal 
from  a  pictorial  composition  the  all-impor- 
tant element  of  dramatic  impact. 

In  motion  pictures,  where  no  retouching  is 
possible,  lighting  has  been  developed  into  a 
major  art.  Mr.  Alton,  a  master  of  his  craft, 
discusses  fully  both  the  technical  and  artistic 
aspects  of  lighting — just  what  lights  are  used 
and  where  placed,  the  special  tricks  of 
photography  to  obtain  special  effects,  and  the 
1001   elements   that  enter  into  this  art. 

Every  light,  from  senior  solar  spot  to  the 
inky-dinkie;  every  reflector  for  either  indoor 
or  outdoor  work,  the  gobos,  flags,  cookies, 
diffusors,  filters,  screens  and  all  the  many 
gadgets  used  in  professional  lighting  are 
clearly  explained  and  shown  in  a  prodigal 
use  of  illustrations.  There  are  many  useful 
facts  on  lenses,  on  cameras  and  their  care, 
and  on  developing.  The  importance  of  color 
is  stressed  and  explained. 

Here  is  great  value  to  the  photographer, 
professional  or  amateur,  and  here  too  is 
much  that  is  profitable  to  architects,  decora- 
tors, artists,  restaurateurs  and  all  those  who 
strive  for  the  best  in  pictorial  effect. 


\jreetinaS  and 
Bed    WisLs 
for  1 930  from 

DETROIT  PROJECTIONISTS' 
LOCAL  NO.  100 
I.    A.    T.    S.    E. 

• 


30 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


FULL  TEXT  OF  CALIF. 
HIGH  COURT  DECISION 

(Continued  from  page  16) 

date  directing  defendants  to  admit  plaintiffs 
to  full  journeyman  membership  and  an  in- 
junction restraining  defendants  from  inter- 
fering with  plaintiff's  employment  or  refus- 
ing to  dispatch  them  to  employment  with 
seniority  and  other  rights  equal  to  those  of 
journeyman  members. 

Plaintiffs  have  appealed  from  portions  of 
the  judgment  which  denied  them  general 
and  exemplary  damages.  The  judgment  also 
allowed  plaintiffs  certain  sums  as  over- 
charges in  dues,  but  these  sums  have  been 
paid  and  are  not  included  in  the  present 
appeals. 

Local  162  is  affiliated  with  the  Interna- 
tional Alliance  of  Theatrical  Stage  Employ- 
ees and  Moving  Picture  Operators  of  the 
United  States  and  Canada,  hereinafter  called 
the  International,  which  is  chartered  by  the 
American  Federation  of  Labor.  The  local 
has  jurisdiction  over  projectionists  employed 
in  San  Francisco  and  Marin  Counties,  and 
it  has  either  written  or  oral  contracts  with 
at  least  75  of  the  approximately  80  motion 
picture  theatres  in  the  area  that  they  will 
employ  only  members  of  the  local  or  persons 
dispatched  by  it  as  projectionists. 

Status  of  'Outside*  Members 

Members  of  the  locals  are  also  members 
of  the  International,  and,  under  its  constitu- 
tion, they  may  secure  work  in  areas  beyond 
the  jurisdiction  of  their  home  locals  by  ap- 
plying to  the  local  situated  where  employ- 
ment is  desired,  but  they  may  remain  mem- 
bers of  their  home  locals  instead  of  joining 
the  local  which  dispatches  them  to  work. 
Workers  having  this  status  were  referred  to 
at  the  trial  as  "outside  members"  or  "visiting 
members"  of  Local  162. 

Outside  members  have  no  right  to  vote  or 
otherwise  participate  in  the  local's  affairs, 
and  they  have  limited  rights  to  work.  All 
positions  within  the  jurisdiction  of  a  local 
must  be  filled  by  its  own  members,  but  if  the 
local  membership  is  unable  to  care  for  all 
vacancies,  preference  must  be  given  to  mem- 
bers of  affiliated  sister  locals,  and  persons 
not  members  of  the  International  may  not 
be  given  employment  until  all  members  of 
resident  and  out-of-town  locals  have  been 
employed. 

Under  the  International's  constitution, 
each  member  must  obtain  from  his  home  lo- 
cal a  "working  card,"  which  appears  to  be 
in  the  nature  of  a  membership  card,  and 
before  accepting  a  position  in  the  jurisdic- 
tion of  another  local  he  must  deposit  his 
working  card  with  the  secretary  of  the  sister 
local  who  holds  this  card  until  the  member 
leaves  the  jurisdiction.  (Const,  of  Internat., 
Art.  21,  Sec.  7,  8). 

An  outside  member  who  wishes  to  join 
the  local  which  dispatches  him  to  work, 
instead  of  remaining  in  the  status  of  an  out- 
side   or    visiting    member,    may    proceed    by 


*  This  transfer  card  relates  only  to  the  transfer 
of  membership  from  one  local  to  another,  and  it 
is  not  to  be  confused  with  the  working  card 
which  is  in  the  nature  of  a  membership  card 
issued  by  the  home  local  and  is  necessary  to 
secure  work  either  within  or  without  the  juris- 
diction of  the  home  local.  (Const,  of  Internat., 
Art.  21.  Sec.  7.) 


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INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


31 


either  of  two  distinct  methods  authorized  by 
the  International  constitution: 

Membership  Procedure 

(I)  by  "application  for  membership  .  .  . 
upon  the  official  printed  form  of  this  Alliance, 
to  be  supplied  to  the  applicant  by  the  local 
union  to  which  he  seeks  admission"  (Const. 
of  Internat..  Art.  21.  Sec.  2)  ;  or  (2)  by 
obtaining  a  "transfer  card"*  from  his  home 
local  and  presenting  this  card  to  the  local 
with  which  he  desires  to  become  affiliated 
(Const,  of  Internat.  Art.  19,  Sec.  18).  Under 
either  of  these  methods  the  applicant  must 
obtain  the  approval  of  the  local  to  which 
he  applies. 

For  many  years  plaintiffs  have  been  mem- 
bers of  locals  situated  in  other  states,  Dotson 


being  a  member  of  an  Arkansas  local  and 
Murrah  of  one  in  Oklahoma,  and  they  re- 
mained members  in  good  standing,  of  their 
home  locals  at  all  times  involved  herein. 

Murrah  came  to  San  Francisco  in  No- 
vember, 1938,  and  Dotson  arrived  in  Feb- 
ruary, 1939.  They  did  not  apply  for  member- 
ship or  present  transfer  cards  to  Local  162 
but,  rather,  deposited  their  working  cards 
with  the  local,  and  they  were  assigned  to 
work  as  outside  members.  They  continued 
to  pay  dues  to  their  respective  home  locals, 
remaining  members  thereof,  and  they  were 
dispatched  to  work  because  as  members  of 
their  home  locals  they  were  also  members 
of  the  International. 

Plaintiffs  and  other  outside  men  consulted 
a  law  firm,  which,  on  Mareh  7,  1945,  wrote 


THE  "  '/% 

STRONGS 
T  R  O  U  P  E  m. 

Portable  High  Intensity/// 

A.  C.  CARBON  ARC  SPOTLIGHT 


Produces  a  steady,  sharp,  uniformly 
illuminated  snow-white  spot. 

Silvered  glass  reflector  and  two- 
element  variable  focal  length  lens 
system. 

Draws  only  10  amperes  from  any 
110-volt  A.C.  convenience  outlet. 
Adjustable,  self- regulating  trans- 
former, an  integral  part  of  the  base, 
makes  the  use  of  heavy  rotating 
equipment  unnecessary. 


Easily  operated.  Automatfe  arc 
control  maintains  constant  arc  gap, 
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of  carbons  burns  one  hour  and  20 
minutes raf  21  volts  dhd  45  amperes. 

Horizontal  masking  controls'  Can 
be  angled  at  45  'degrees1  Iti  each 
direction."  Color  boomerang  con- 
tains six  slides  and  ultraviolet  filter 
holder. 

Mounted  on  castjers.  Easily  dis- 
assembled for  shipping. 


THE 

STRONG 

ELECTRIC  CORP. 

"The  World's  Largest  Manu- 
facturer of  Projection 


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dealer  in  Strong  Spotlights. 


NAME 

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,  vjl/ 


a  letter  to  the  president  of  the  International 
stating  that  certain  visiting  members  of  Local 
162,  whose  names  were  not  disclosed,  desired 
to  become  members  of  Local  162  but  that  the 
local  refused  to  admit  them.  The  letter  fur- 
ther stated  that  the  local  engaged  in  other 
assertedly  improper  and  discriminatory  prac- 
tices, that  the  outside  members  were  con- 
sidering the  possibility  of  litigation,  and 
that  they  wished  the  International's  president 
to  investigate  the  matter. 

Copies  of  this  letter  and  of  a  second  simi- 
lar one  from  the  law  firm  were  sent  by  the 
International  to  Local  162.  Much  resentment 
developed  in  the  local,  because  its  officers 
felt  that  the  letters  to  the  International 
should  not  have  been  sent  without  revealing 
the  names  of  the  complainants,  that  the 
charges  should  first  have  been  presented  to 
the  local,  and  that  the  outside  members 
should  not  have  hired  attorneys  who,  it  was 
claimed,  represented  C.I.O.  unions  and  Com- 
munists. 

.There  is  testimony,  though  denied,  that  at 
a  union  meeting,  Billingsley,  the  local's  busi- 
ness agent,  stated  that  the  men  responsible 
for  the  letters  had  "consulted  a  phony 
'Commy'  lawyer"  and  that  "as  soon  as  they 
were  sure  who  the  men  were  that  they  would 
be  on  their  way  out  of  town." 

Voluntary  Withdrawal  of  Card 

Plaintiffs  were  accused  of  having  caused 
the  letters  to  be  sent  to  the  International;  but 
they  denied  the  fact.  Murrah  subsequently 
told  Billingsley  that  he  did  not  desire  to  re- 
main at  work  while  the  question  of  who  sent 
the  letters  was  being  investigated.  After 
giving  the  required  two  weeks'  notice  for 
leaving  work,  he  quit  on  July  13,  1945,  and 
on  July  15,  he  requested  return  of  his  work- 
ing card  or  membership  card,  which  was 
mailed  to  him  the  next  day  and  was  never 
redeposited  with  the  local. 

Dotson  last  worked  in  San  Francisco  as 
an  out-of-town  member  on  July  24,  1945.  The 
working  card  which  he  had  deposited  with 
Local  162  expired  on  August  1,  1945,  and 
when  he  received  a  new  working  card  from 
his  home  local  he  kept  it  and  did  not  deposit 
it  with  Local  162  but  obtained  work  else- 
where. 

On  at  least  two  occasions  in  August  and 
October,  1945,  plaintiffs  asked  Billingsley  if 
there  was  any  work  for  them ;  and  Billingsley 
replied  that  there  was  none. 

At  the  trial  plaintiffs  based  their  claims 
with  respect  to  membership  in  Local  162 
upon  two  somewhat  inconsistent  theories: 
first,  that  the"  local-  had  actually  accepted 
them  as  mehiberS  by  permitting  them  to 
work  under  its  jurisdiction  for  a  number  of 
years  but  nevertheless  Wrongfully  deprived 
them  of  the  privileges  and  indicia  of  full 
membership;  and  second,  that  the  local 
maintained  ctesed-shop  contracts  with  em- 
ployers and  aVthe  same  time  arbitrarily  re- 
fused to  admit  plaintiffs  to  membership1 6r 
dispatch  them  to  work. 

Lower  Court's  Findings 

It  was  also  asserted  that  defendants,  actu- 
ated by  malice,  conspired  to  deprive  plaintiffs 
of  their  emplpyment  as  projectionists,  en- 
titling them  to  both  general  and  exemplary 
damages.      "/    <., 

The  trial  court  found  that  plaintiffs  had 
not   become    members   of   or   transferred    to 


32 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


Local  162  but  had  paid  dues  to  and  remained 
members  of  their  out-of-state  locals,  and  the 
evidence  is  ample  to  support  this  finding. 
The  court  found  and  concluded,  however, 
that  the  local  had  closed-shop  contracts  with 
practically  all  of  the  thearers  in  the  area  and 
that  it  had  maintained  an  arbitrarily-closed 
union  from  1919  until  the  time  of  trial ;  and 
the  local  was  ordered  to  admit  plaintiffs  to 
full  journeyman  membership  and  was  en- 
joined from  interfering'  with  their  employ- 
ment as  projectionists. 

It  was  further  found '  that  there  was  no 
conspiracy,  fraud, '  malice,  intimidation  or 
coercion  on  the  part  of  defendants  to  deprive 
plaintiffs  of  their  livelihood  or  to  deny  them 
admission  into  the  local,  and  that  plaintiffs, 
in  July,  1945,  had  picked  up  the  membership 
cards  which  they  had  deposited  with  Local 
162  and  therefore  were  not  available  for 
work  within  the  jurisdiction.  Apparently 
upon  the  basis  of  these  findings,  the  court 
denied  plaintiffs'  claim  for  general  and  ex- 
emplary damages. 

Basis  of  Defendants'  Appeal 

The  principal  question  presented  by  de- 
fendants' appeal  is  whether  plaintiffs  have 
established  a  right  to  relief  under  the  recent 
decisions  of  this  court  that  a  labor  organiza- 
tion may  not  properly  maintain  both  a  closed 
shop  and  an  arbitrarily  closed  or  partially 
closed  union  (James  V.  Marinship  Corp.,  25 
Cal.,  2nd,  721 :  Williams  v.  Int.  etc.,  of  Boiler- 
makers, 27  Cal.,  2nd,  586;  Thompson  v. 
Moore  Drydock  Co.,  27  Cal.,  2nd,  595). 

These  decisions  also  hold  that  an  employee 
who  has  been  injured  by  a  union's  conduct 
in  violation  of  this  principle  may  obtain  an 
injunction  ordering  the  union,  in  the  alterna- 
tive, either  to  admit  him  to  full  membership 
upon  reasonable  terms  and  conditions  ap- 
plicable to  all  persons,  or  to  refrain  from  pre- 
venting his  employment  upon  the  ground  that 
he  does  not  belong  to  the  union. 

In  the  present  case  plaintiffs  have  estab- 
lished that  Local  162  maintains  closed-shop 
agreements  with  practically  all  of  the  thea- 
ters within  its  jurisdiction  and  that  it  is 
impossible  for  moving  picture  machine  oper- 
ators to  obtain  work  unless  they  are  dis- 
patched by  the  local.  Further,  it  is  clear  that 
defendants  cannot  satisfy  their  duties  under 
the  Marinship  case  by  offering  to  resume  dis- 
patching plaintiffs  to  work  as  outside  men, 
because  the  record  shows  that  giving  plain- 
tiffs work  in  this  manner  would  not  be 
equivalent  to  granting  them  full  membership 
in  Local  162. 

Basic  Question  at  Issue 

As  visiting  members,  plaintiffs  would  have 
few  of  the  privileges  accorded  to  regular 
members:  for  instance,  they  would  not  be 
allowed  to  vote  for  officers  or  upon  matters' 
of  union  policy,  and  their  seniority  rights,  if, 
existing  at  all,  would  not  be  equal  to  those 
of  members.  Although  they  would  be  under 
the  control  of  the  local  and  would  be  re- 
quired to  pay  the  same  percentage  of  their 
wages  as  is  paid  by  regular  members  of  the 
local,  they  would  be  kept  in  an  inferior 
status  analogous  to  that  of  the  auxiliary 
membership  considered  in  James  v.  Marin- 
ship Corp.,  25  Cal.,  2nd,  721,  and- the  Junior 
membership  condemned  in  Cameron  v.  Inter- 
national Alliance,  etc.  (N.J.  Eq.)  176  Atl. 
692. 


The  basic  question,  therefore,  insofar  as 
defendants'  appeal  is  concerned,  is  whether 
plaintiffs  have  been  arbitrarily  excluded  from 
full  journeyman  membership  in  Local  162. 

Whether  or  not  a  labor  organization  is 
arbitrarily  closed  to  a  particular  worker  de- 
pends, of  course,  upon  the  facts  of  each  case, 
and  it  is  plaintiffs'  burden  to  prove  that  they 
are  entitled  to  membership,  that  membership 
is  closed  to  them,  and  that  it  is  arbitrarily 
closed,  since  these  matters  are  essential  parts 
of  their  cause  of  action  under  the  Marinship 
case. 

Not  'Compelled'  to  Admit 

Defendants  contend  that  plaintiffs  have 
not  met  this  burden,  and  that  the  trial  court 
erred  in  granting  the  requested  relief,  be- 
cause plaintiffs  have  not  shown  either  that 
they  are  able  and  willing  to  comply  with  the 
requirements  and  regulations  of  the  union 
or  that  the  requirements  are  unreasonable. 

As  recognized  in  the  Marinship  case,  a 
union  is  not  compelled  to  admit  all  persons 
as  a  condition  to  maintaining  closed-shop 
agreements,  and  it  has  the  "right  ...  to 
reject  or  expel  persons  who  refuse  to  abide 
by  any  reasonable  regulation  or  lawful  policy 
adopted  by  the  union."  (James  v.  Marinship 
Corp.,  25  Cal.,  2nd,  721,  736.) 

For  example,  the  court  there  in  effect  up- 
held the  right  of  the  union  to  impose  initia- 
tion fees  and  dues.  It  has  also  been  held  that 
an  assessment  of  union  members  for  the  pur- 
pose of  opposing  a  proposed  amendment  to 


from 

LOCAL 

NO 

.  373 

Terre   Haute 

Indiana 

^rroiiaau 

Ljreetinai 

LOCAL 

NO. 

165 

Hollywood               Calif. 

the  State  Constitution  is  reasonable,  and  that 
a  member's  refusal  to  pay  the  assessment 
can  properly  result  in  suspension  of  his 
membership  and,  consequently,  by  virtue  of 
collective  bargaining  contracts,  loss  of  his 
right  to  perform  radio  services  or  produce 
radio  (De  Mille  v.  American  Fed.  of  Radio 
Artists,  31  Cal.,  2nd,  129) .  Clearly  a  union 
cannot  be  said  to  have  acted  arbitrarily  in 
withholding  membership  from  an  applicant 
who   does   not  meet  all   reasonable   require- 


PtfKUS„Sr 

Undisputed l  w  .^ 

Poland  large 
both  srnou  « 
theatres. 


BETTER 

PROJECTION 

LIGHTING 

for  Theatres  of  Every  Size 


J 


fdrive->n   LSQTrce   for 

freely  larl  -     *"«* 
1*heatres/       ge  '"door 


EQUIPMENT    AND    SUPPLIES    FO*    EVERY    THEATRE    MEED 


NATIONAL 

■iiif.m«oa 

Ptvrtt**   •(  *t**t«ft<if  *  Si»*4f ,  *  1>»<1* 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


33 


merits    or    qualifications    prescribed    by    the 
union  as  conditions  of  membership. 

IA  Constitutional  Requirements 

Here  it  appears  that  the  constitution  of 
the  International  authorizes  only  two  meth- 
ods by  which  a  person  may  become  a  mem- 
ber of  an  affiliated  local,  that  is,  by  "applica- 
tion for  membership  .  '.  .  upon  the  official 
printed  form  of  this  Alliance,"  or  by  obtain- 
ing a  "transfer  card"  from  the  local  of  which 
he  is  a  member  and  presenting  this  card  to 
the  local  which  he  desires  to  join. 

The  application  blank  provided  for  in  the 
By-Laws  of  the  International  contains  a  state- 
ment that  the  applicant  authorizes  the  local 
to  which  he  applies  to  be  his  exclusive  agency 
for  collective  bargaining  and  that  he  agrees 
to  abide  by  the  rules  of  the  local  and   the 


International.  The  form  also  requires  certain 
information,  including  a  list  of  theaters, 
laboratories,  and  studios  where  the  applicant 
has  worked,  apparently  to  assist  an  investi- 
gation and  appraisal  of  his  qualifications, 
and  the  making  of  an  application  obviously 
constitutes  a  part  of  the  union's  regular  pro- 
cedure in  processing  new  members. 

Murrah,  however,  testified  that  he  had  not 
presented  an  application  for  membership  or 
a  transfer  card  to  Local  162;  and  there  is  no 
evidence  that  Dotson  ever  applied  for  mem- 
bership by  either  method.  To  the  contrary, 
plaintiffs  admit  in  their  briefs  that  they 
did  not  apply. 

Further,  the  constitution  of  the  Interna- 
tional prescribes  certain  other  qualifications, 
such  as  that  the  applicant  must  be  a  citizen 
of  the  United  States  or  Canada,  that  he  must 


ANSWER 
TO  YOUR 
TECHNICAL 
PROBLEMS . . . 


The  Altec 
Service  Man  and 
the  organization 
behind  him 


161  Sixth  Avenue, 
New  York  13,  N.  Y. 

PROTECTING  THE  THEATRE—FIRST  PLACE  IN  ENTERTAINMENT 


^eadon  A     Ljreetinad    tr 


:inad    from 

PROJECTIONISTS  LOCAL  ONION  NO.  228 
I.  A.  T.  S.  E.     &     M.  P.  M.  0. 

TOLEDO,  OHIO 


not  be  a  member  of  "any  organization  having 
for  its  aim  or  purpose  the  overthrow,  by  force, 
of  the  Constitution  and  Government  of  the 
United  States  or  the  Government  of  the 
Dominion  of  Canada,"  and  that  he  must  be 
of  good  moral  character  and  reputation 
(Const,  of  Internat.,  Art.  1,  Sec.  3;  Art.  21, 
Sec.  1 ) .  A  member  found  to  lack  any  of  the 
qualifications  is  subject  to  expulsion  (Const, 
of  Internat.,  Art.  1,  Sec.  3). 

Local  Union  Requirements 

The  constitution  of  Local  162  provides 
certain  other  prerequisites  for  membership, 
among  which  are  payment  of  $250  initiation 
fee  (Const,  of  Local  162,  Art.  2,  Sec.  4),  and 
presentation  of  a  physician's  certificate  that 
the  applicant  is  free  of  tuberculosis  and  is 
physically  able  to  perform  the  duties  required 
of  him  (Const,  of  Local  162,  Art.  2,  Sec.  2.). 

Plaintiffs  do  not  claim  that  any  of  the 
foregoing  qualifications  or  requirements  for 
membership  is  unreasonable  or  beyond  the 
scope  of  legitimate  activity  of  a  labor  union, 
and  this  question  is  not  before  us. 

The  trial  court  did  not  make  findings  as  to 
plaintiffs'  qualifications  for  membership  ex- 
cept that  they  were  competent  and  qualified 
moving  picture  machine  operators  and  pro- 
jectionists, and  no  attempt  was  made  by 
plaintiffs  to  prove  compliance  or  ability  to 
comply  with  all  the  terms  and  conditions 
prescribed  by  the  constitution,  nor  did  they 
offer  to  comply. 

Further,  it  is  admitted  that  plaintiffs  did 
not  apply  for  membership,  and  they  state 
that  at  trial  they  relied  on  the  belief  that 
an  application  was  not  necessary  in  order  to 
bring  them  within  the  rule  of  James  v. 
Marinship  Corp.,  25  Cal.,  2nd,  721.  This 
position  is,  of  course,  without  merit,  since 
the  Marinship  case  expressly  recognized  the 
right  of  a  union  to  impose  reasonable  re- 
quirements as  conditions  of  obtaining  mem- 
bership. 

Membership  Application  'Idle  Act* 

Plaintiffs  also  say  that  they  did  not  apply 
for  membership  because  it  would  have  been 
an  idle  act,  and,  although  not  expressly 
argued,  they  apparently  rely  upon  this  theory 
as  an  excuse  for  failure  to  meet  other  re- 
quirements  of  the  union.  In  support  of  their 
contention  they  point  to  evidence  which  they 
assert  establishes  that  any  application  would 
have  been  arbitrarily  rejected. 

The  record  shows  that  from  1924  to  July, 
1945,  no  outside  men  had  been  admitted  to 
membership,  although  five  were  admitted  in 
August,  1945,  before  the  complaint  was  filed 
herein,  and  six  were  admitted  after  the  com- 
plaint was  filed  but  before  trial. 

There  is  also  evidence  of  statements  and 
conduct  by  the  local's  officers  from  which 
plaintiffs  could  reasonably  have  believed  that 
no  outside  man  would  be  admitted  without 
the  personal  approval  of  Billingsley,  the 
local's  business  agent,  and  that  Billingsley 
would  not  approve  plaintiffs  as  members  be- 
cause they  were  suspected  of  having  insti- 
gated the  writing  of  the  letters  to  the  presi- 
dent of  the  International  containing  the 
charges  made  against  Local  162. 

The  evidence,  although  conflicting  and 
not  entirely  satisfactory,  is  sufficient,  when 
considered  as  a  whole,  to  show  that  defend- 
ants in  effect  told  plaintiffs  that  they  could 


34 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


not  become  members  of  Local  162  and  that 
it  would  be  useless  and  an  idle  act  for  them 
to  apply.  The  trial  court  made  no  specific 
finding  upon  this  issue,  but  it  did  conclude 
that  Local  162  had  maintained  an  arbitrarily- 
closed  union  from  1919  until  the  time  of  trial, 
and  this  may  be  sufficient  to  permit  implica- 
tion of  a  finding  that  it  would  have  been 
useless  for  plaintiffs  to  apply. 

The  question  need  not  be  determined  here, 
however,  because  on  the  record  before  us  an 
express  finding  to  this  effect  would  not,  with- 
out more,  be  sufficient  to  entitle  plaintiffs 
to  a  judgment  for  the  reason  that  they  did 
not  attempt  at  the  trial  to  prove  compliance 
with  the  terms  and  conditions  prescribed  by 
the  union,  nor  did  they  offer  to  comply. 

Compliance  With  Requirements 

Even  if  we  assume  that  it  would  have  been 
an  idle  act  for  plaintiffs  to  apply  for  mem- 
bership and  to  make  an  offer  to  comply  with 
other  requirements  of  the  union  prior  to 
commencement  of  the  action,  it  was  never- 
theless incumbent  upon  them  at  trial  to 
establish  compliance  or  offer  to  comply  with 
all  reasonable  terms  and  conditions  pre- 
scribed by  the  union. 

In  the  absence  of  such  a  showing  or  offer, 
they  were  not  entitled  to  compel  specific 
performance  of  the  duty  imposed  on  the 
union  by  the  doctrine  of  the  Marinship  case 
to  admit  them  to  membership  or  to  refrain 
from  interfering  with  their  right  to  work. 

Obviously,  proof  that  it  would  have  been 
an  idle  act  for  plaintiffs  to  make  an  applica- 
tion would  not  establish  that  they  are  quali- 
fied as  members  or  that  they  are  able  and 
willing  to  meet  the  requirements  for  mem- 
bership. Since  a  union  is  not  required  to 
accept  as  members  persons  who  do  not  meet 
reasonable  conditions  imposed  by  it,  the 
court  could  not  properly  grant  the  relief 
requested  unless  plaintiffs  were  able  and 
willing  to  comply  with  all  reasonable  regu- 
lations. 

The  matter  clearly  is  not  one  of  mere 
formality,  because  if  courts  were  to  order 
admission  of  persons  into  a  union  without 
requiring  compliance  with  reasonable  condi- 
tions, it  would  in  effect  give  such  persons 
rights  and  privileges  beyond  those  extended 
to  regular  members  and  might  lead  to  dis- 
ruption of  the  union  (see  James  v.  Marinship 
Corp.,  25  Cal.  2nd,  721,  736). 

Analogy  in  Law   of   Contracts 

Closely  analogous  is  a  problem  arising 
under  the  law  of  contracts,  where  it  is  the 
settled    rule    that    although    an    unqualified 


repudiation  by  the  promisor  may  excuse 
tender  or  performance  of  conditions  prece- 
dent in  advance  of  suit,  it  does  not  excuse 
a  party,  when  seeking  specific  performance, 
from  pleading  and  proving  at  trial  that  he 
is  ready,  able,  and  willing  to  perform  the 
contractual  conditions  (see  Buckmaster  v. 
Bertram,  186  Cal.,  673,  678;  Ray  Thomas, 
Inc.,  v.  Cowan,  99  Cal.,  app.,  140,  146; 
Cockrill  v.  Boas,  213  Cal.,  490,  492;  4  Pom- 
eroy,  Equity  Jurisprudence  (5th  ed.,  1941) 
1051;   49  Am.  Jur.,  184). 

It  follows  that  proof  that  plaintiffs'  appli- 
cations would  have  been  arbitrarily  rejected 
would  not  relieve  them  of  the  necessity  of 
showing  at  the  trial  that  the  union's  condi- 
tions for  membership  were  unreasonable  and 
contrary  to  public  policy,  or  that  plaintiffs 
had  complied  with  the  requirements  or  at 
least  had  made  an  offer  to  do  so,  coupled 
with  proof  of  ability. 

Plaintiffs,  however,  assert  that  under  the 
constitution  of  the  International  they  have  an 
absolute  right  to  be  admitted  as  transfer 
members  and  that  Local  162  has  refused  to 
accept  any  outside  men  by  this  method;  and 
they  have  requested  this  court  to  receive 
additional  evidence  for  the  purpose  of  show 
ing  that  the  local  has  ignored  the  transfer 
card  provision  of  the  International's  consti- 
tution. 

LocaVs  Right  of  Rejection 

There  is  no  merit  in  this  position.  While 
the  constitution  of  the  International  compels 
a  local  to  issue  transfer  cards  to  its  members, 
the  constitution  does  not  compel  a  local  to 
accept  members  by  the  transfer  method. 
Instead  it  recognizes  the  right  of  the  local 
to  which  the  card  is  presented  to  reject  the 
applicant,  and  there  is  nothing  therein  which 
forbids  the  practice  adopted  by  Local  162 
of  requiring  outside  men  to  meet  some  or  all 
of  the  qualifications  required  of  new  mem- 
bers. 

This,  of  course,  does  not  mean  that  there 
is  any  right  to  reject  outside  men  arbitrarily. 
since  under  the  Marinship  doctrine,  as  we 
have  seen,  a  union  must  either  accept  all 
applicants  for  membership  upon  compliance 
with  reasonable  terms  and  conditions,  or 
refrain  from  interfering  with  their  right  to 
work. 

However,  it  does  not  appear  that  there  is 
anything  improper  or  contrary  to  public 
policy  in  the  requirement  of  Local  162  that 
outside  men  file  an  application  and  submit 
to  a  re-examination  of  their  qualifications  as 
a  condition  for  membership.  The  mere  fact 
that  an  outside  man  may  have  originally  com- 


(gmttnQs  ani  !?Bt  Mtsljefi  from 

LOCAL  UNION  NO.  223 


LEON  ROSENBLATT— Secretary 
and  Treasurer,  Rosenblatt-Welt 
Corporation,  New  York,  N.  Y. — 
says: 

"We  are  celebrating  our  20th 
year  with  RCA  equipment  and 
service,  and  find  it  the  best 
insurance  for  good  sound." 

To  get  the  benefits  of  RCA  Service 
—write:  RCA  SERVICE  COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


Providence,  R.  I. 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


35 


plied  with  the  requirements  of  the  Interna- 
tional at  the  time  he  joined  his  home  local, 
does  not  mean  that  he  still  meets  those 
qualifications,  nor  does  it  in  any  way  indicate 
that  he  can  and  does  meet  other  reasonable 
conditions  imposed  by  Local  162. 

In  the  absence  of  a  showing  that  the  con- 
stitution of  the  International  precludes  Local 
162  from  requiring  an  application  from  out- 
side members  and  from  imposing  other  re- 
quirements as  conditions  for  membership  or 
that  such  requirements  are  unreasonable, 
plaintiffs  have  not  shown  that  they  are  en- 
titled   to    the    requested    relief. 

Requirements  Not  Unreasonable 

There  is  nothing  in  the  additional  evidence 
offered  on  appeal  which  tends  to  prove  that 
plaintiffs  have  complied  with  the  local's  re- 
quirements   for    membership    or    that    those 


requirements  are  unreasonable.  Plaintiffs 
merely  offered  to  prove  that,  after  the  de- 
cision by  the  District  Court  of  Appeal, 
Murrah  and  a  third  person  presented  trans- 
fer cards  to  Local  162,  but  were  notified  that 
their  cards  had  been  rejected  without  preju- 
dice to  their  right  to  become  members  by 
the  application  method. 

This  evidence,  if  true,  would  not  justify 
or  require  affirmance  of  the  judgment.  Plain- 
tiffs, therefore,  are  not  entitled  to  its  ad- 
mission on  appeal,  and  the  request  is  denied. 
The  offer  of  defendants  to  present  rebuttal 
evidence   is   also   denied. 

The  judgment  must  be  reversed  for  the 
reasons  above  stated,  and  it  is  unnecessary 
to  discuss  defendants'  further  ground  for 
reversal  that  plaintiffs  failed  to  exhaust 
their  remedies,  within  the  machinery  pro- 
vided   by    the    union,    by    appealing    to    the 


THIS  IS  WHAT  IfoU 

Customer  satisfaction— the  theatre 
owner's  #  I  asset.  Create  it  by  using 
CENTURY    PROJECTION    AND    SOUND 

SYSTEMS.  For  the  smallest  to 
the     largest  Drive-in    for  harmony 

of  color  tone  and  picture  brilliance. 


Sold  through  recognized 
theatre  supply  dealers 


CENTURY  PROJECTOR  CORP. 


New  York,  N.  Y. 


SSWBWSSrSSSrt^^ 


(J->est    Wishes   from, 

drerttttgii  tram 

LOCAL    NO.    257 

STAGE    EMPLOYES 
LOCAL     NO.     366 

OTTAWA,  ONT. 

WESTCHESTER  COUNTY 

CANADA 

NEW  YORK 

g>m&an&  (ImtutQH 

^r4oiidau    LureetinaS 

CLAYTON    PRODUCTS   CO. 

LOCAL    NO.     171 

31-45    Tibberr    Avenue 
New    York    63,    N.    Y. 

PITTSBURGH 
PENNA. 

president  of  the  International  or  to  the 
general  executive  board  or  the  convention  of 
the  International. 

Basis  of  Plaintiffs9  Appeal 

Plaintiffs  claim  that  the  court  erred  in 
denying  them  both  general  and  exemplary 
damages,  and  they  rely  in  part  upon  their 
testimony  that  they  were  forced  to  leave 
their  work  and  in  part  upon  the  finding  of 
the  trial  court  that  since  July,  1945,  de- 
fendants have  not  made  work  available  to 
them  and  have  not  dispatched  them  to 
employment. 

The  refusal  to  allow  damages  may  not  be 
successfully  attacked  upon  the  theory  that 
plaintiffs  were  forced  to  leave  their  work, 
because  the  evidence  is  clearly  sufficient  to 
support  the  specific  finding  of  the  trial  court 
that  "it  is  not  true  that  a  conspiracy  existed 
or  that  fraud,  malice,  intimidation  or  coer- 
cion was  practiced  by  or  on  the  part  of  de- 
fendants ...  to  deprive  plaintiffs  of  their 
livelihood  as  motion  picture  operators  or  of 
their  membership  in  the  International  union, 
or  to  deny  them  admission  into  Local  162." 

Nor  can  the  court's  refusal  to  grant  dam- 
ages be  attacked  on  the  ground  that  plain- 
tiffs were  not  dispatched  to  work  as  outside 
members,  since  the  constitution  of  the  In- 
ternational provides  that  outside  men  must 
keep  their  working  cards  on  deposit  with  the 
local,  and  plaintiffs  admit  that  they  had 
picked   up   their  working  cards. 

The  provision  requiring  deposit  of  working 
cards,  however,  applies  only  to  outside  men, 
not  to  regular  members.  If  plaintiffs  were 
qualified  for  full  membership  in  Local  162, 
but  defendants  nevertheless  arbitrarily  de- 
nied them  admission  and  at  the  same  time 
refused  to  permit  them  to  work  without  be- 
longing to  the  local,  plaintiffs  would  be 
entitled  to  recover  damages  for  wrongful 
interference  with  their  right  to  work  (see 
James  v.  Marinship  Corp.,  25  Cal.,  2d,  721, 
728-729;  Rest.,  Torts.  Sec.  766,  810;  31 
Am.  Jur.  844  et  seq.;  30  Am.  Jur.  64; 
Brotherhood  of  Locomotive  Firemen,  etc., 
v.  Tunstall,  163  F.  2nd,  289,  293;  Smether- 
ham  v.  Laundry  Workers'  Union,  44  Cal. 
App.  2d,  131,  135). 

No   Wrongful  Work  Interference 

The  trial  court's  findings  show  that  plain- 
tiffs' earnings  were  greatly  reduced  after  they 
stopped  working  in  the  jurisdiction  of  Local 
162.  No  findings  were  made,  however,  re- 
lating to  plaintiffs'  right  to  damages  on  the 
theory  that  the  reduction  in  their  earnings 
was  caused  by  a  wrongful  interference  with 
their  right  to  work,  and  the  denial  of  dam- 
ages, at  least  in  the  absence  of  findings  upon 
the  matter,  is  inconsistent  with  the  court's 
conclusion  that  plaintiffs  were  entitled  to 
the  status  of  full  membership  and  should 
have  been  given  that  status  retroactive  to 
June  29,  1945. 

Inasmuch  as  the  portions  of  the  judgment 
pertaining  to  plaintiffs'  rights  to  full  mem- 
bership must  be  reversed,  and  since  the 
right  to  damages  depends,  at  least  in  part, 
upon  the  outcome  of  the  membership  issue, 
the  entire  matter  should  be  remanded  to  the 
trial  court  so  that  all  of  the  problems  may  be 
considered  together. 

All  portions  of  the  judgment  appealed 
from  are  reversed. 


36 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


THEATER     TELEVISION: 
WHAT,  HOW  AND  WHEN 

(Continued  from  page  21) 

temporary  authorizations  (STA's)  issued 
for  90-day  periods  and  terminable  by  the 
FCC  without  advance  notice.  These 
authorizations  are  for  frequencies  allo- 
cated either  to  the  use  of  Tv  broadcast 
stations  (not  to  theater  Tv,  a  distinct  and 
separate  service)  or  to  various  non-broad- 
cast services.  Theater  Tv  canot  expect  to 
use  these  frequencies  for  a  regular  thea- 
ter service. 

The  motion  picture  industry  since  1944 


Attention, 
Proj  ection  is  ts  ! 

Now  you  can  mark  your  Titles, 

Reel    Numbers,    Start    Marks, 

etc.,  the  modern  way  with 

POCKET  MARKER 

Always  ready  for  your  instant 

use,  with  sample  bottle  of  red 

or  yellow  ink. 


$3-25 


Postpaid 


Save  c.o.d.  charges  by  remit- 
ting $3.25  with  your  order. 
Specify      color      ink      desired. 

Distributed  by 

ALEX    WEISS 

Member,  Local  160,  IATSE 

2781  HAMPSHIRE  ROAD 
CLEVELAND  6,  OHIO 


has  made  sporadic  efforts  to  obtain  the 
allocation  of  relay  frequencies  to  theater 
Tv.  The  first  such  bid,  spearheaded  by 
Paul  J.  Larsen  on  behalf  of  the  SMPE, 
was  made  in  the  general  allocation  hear- 
ings held  in  the  fall  of  1944  and  the 
spring  of  1945,  when  the  end  of  the  war 
was  in  sight   (FCC  Docket  6651). 

Film  Industry's  Abortive  Efforts 

Mr.  Larsen  requested  an  allocation  of 
1500  megacycles  in  20-megacycle-wide 
channels  in  the  radio  spectrum  between 
300  and  6300  megacycles  for  the  "imme- 
diately necessary  postwar  theater  Tv  serv- 
ice." This  recommendation  was  keyed  to 
the  situation  in  New  York  City  where, 
Mr.  Larsen  stated,  25  independent  pro- 
ducing and  exhibiting  agencies  might 
compete  in  the  theater  Tv  service. 

For  the  initial  period,  however,  he  as- 
sumed that  15  of  these  agencies  should 
be  provided  with  frequencies,  including 
for  each  of  the  15  agencies  one  remote 
pickup  channel,  one  studio-transmitter 
channel,  one  multiple-addressee  channel, 
and  one  intercity  relay  channel.  He  took 
the  position  that  coaxial  cable  and  wire 
facilities  were  not  sufficient  for  the  mul- 
tiple-addressee system,  since  channels  20 
to  60  megacycles  wide  would  be  required 
and  only  4  megacycles  were  available  on 
the  coaxial  cable. 

Mr.  Larsen  presented  the  argument 
that,  in  view  of  the  relative  size  and  im- 
portance of  the  motion  picture  industry 
($1,600,000,000  gross  income  compared 
to  $280,000,000  gross  income  for  the 
broadcasting  industry)  theater  Tv  should 
be  treated  on  a  "paritv  of  opportunity" 
with  radio  broadcasting.  By  this  phrase 
he  meant  "an  equality  of  opportunity  to 
develop  both  arts"  giving  each  "equal 
opportunity  to  experiment,  to  commer- 
cialize, to  improve,  and  to  expand  to  its 
proper    and    demonstrable   limits." 

In  its  final  report  of  May  25,  1945,  in 
the  general  allocation  hearing,  the  FCC 
allocated  certain  frequency  bands  to 
theater  Tv  on  a  shared  basis  with  other 
services  for  experimental  use  only,  mak- 
ing no  exclusive  allocations. 


Stan,  fienfrnmoitce   with  STAR  CORE 


STAR  CORE,  exclusive  feature  with  the  J""0/"'  c°,t>,°"i  "•'  w<"ld'en°w"»d 

the     largeil     theatres     in     the     U.     5. 

torraine  Carbons  —  a  manufacturing  ihrouaiioiitiiie  world  u»Urr«ine  Co* 

process  that  increases  the  performance  •Featured  in  our  horizomoi-feed 

Of  the  Carbons.  copper-cooird  corbpn.. 

A  more  brilliant,  steadier,  more  con-  **'"  rot  disjmbution  data 

sistent  white  light— more  economically  PADRflWC      INP 

...proven  facts  as  shown  by  tests  vnllDUIlVf    lill/a 

made  under  actually  operating  con-  BOONTON,  N.J. 

ditions.  ucut   vnDir.    in    ulcer   K.u   ctc 


CARBONS,  INC. 


NEW  YORK:  234  WEST  44th  STREET 


WITH   ANY 


LAMP 


IN  ANY  SIZE     THEATRE 


The  bands  on  which  experimental  thea- 
ter Tv  were  permitted  included  the  480- 
to  920-megacycle  band  (on  which  experi- 
mentation with  multiple-addressee  sys- 
tems was  permitted)  subject  to  the 
understanding  "that  the  band  will  be 
used  primarily  for  Tv  broadcasting  to 
the  public,  with  higher  frequencies  being 
more  properly  utilized  by  theater  Tv  and 
relay  operation." 

In  addition,  the  following  bands,  allo- 
cated to  the  Fixed  and  Mobile  service, 
were  made  "available  for  theater  Tv 
experimental  use,  including  multiple- 
addressee  purposes  if  the  need  for  such 
use  can  be  established":  1325  to  1375; 
1750  to  2100;  2450  to  2700;  3900  to 
4400;  5650  to  7050;  10,500  to  13,000; 
16,000  to  18,000;  and  26,000  to  30,000 
megacycles. 

The  FCCrs  final  report  thus  opened  the 
door  for  theater  Tv  experimentation  in 
a  large  portion  of  the  radio  spectrum.  As 
a  practical  matter,  however,  even  in  1949 
equipment  is  available  for  radio  relay 
only  on  the  frequencies  up  to  the  7000- 
megacycle  band,  and  equipment  is  ac- 
tively being  developed  in  the  10,000-  to 
13,000-megacycle  band.  Development  of 
equipment    for   use   in    the    16,000-    and 


P. 


tionists  — 


roiectioniS 

Save  yourselves  trouble.  Use 

ETHYLOID  DOUBLE  ACTION  FILM  CEMENT 

Send  for  free  sample — You  be  the  judge. 

FISHER   MFG.    CO.,    525-29   MERCHANTS    RD. 
Manufacturing  Chemists     ROCHESTER  9,  N.  Y. 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


• 

(greetings 

and 
from 

PEORIA 


LOCAL  NO.  434 
I.    A.    T.    S.    E. 


37 


26.000-megacycle  bands  must  await  the 
future. 

The  1945  allocations  in  the  spectrum 


D.  L.  JOHNSON— Owner,  Strand 
Theatre,   San   Diego,    Calif.— says: 
"RCA  Service  is  the  most  in- 
expensive business  insurance  I 
buy.  RCA's  excellent  mainte- 
nance program  keeps  my  equip- 
ment at  maximum  efficiency." 
To  get  the  benefits  of  RCA  Service- 
write:   RCA  SERVICE    COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


between  1000  and  13,000  megacycles  did 
not  remain  "final"  for  long.  In  Novem- 
ber, 1945,  the  4000-  to  4200-megacycle 
band  was  allocated  to  Air  Navigation 
Aids.  In  July,  1946,  the  FCC  proposed 
an  extensive  reallocation  of  frequencies 
in  the  1000-  to  13,000-megacycle  band. 
A  hearing  was  held  on  this  proposal,  and 
Mr.  Larsen  again  testified  on  behalf  of 
theater  Tv  and  the  SMPE,  on  February 
4.  1947. 

Sought   'Common-Carrier'    Rating 

He  took  the  position  that  theater  Tv 
should  be  classified  by  the  FCC  as  a 
"common-carrier"  service,  entitled  to  use 
the  frequencies  allocated  to  "Common- 
Carrier  Fixed  Circuits."  If  this  classi- 
fication was  not  made,  Mr.  Larson  ob- 
jected to  the  proposal  by  the  FCC  that 
Tv  pickup  and  STL  stations  "will  be 
licensed  only  to  licensees  of  Tv  broadcast 
stations  and  to  common  carriers." 

Finally,  Mr.  Larsen  objected  to  the 
failure  of  the  FCC  to  include  in  its  pro- 
posal frequencies  for  intercity  Tv  relay, 
which  the  FCC  stated  could  not  be  ac- 
commodated in  the  1000-  to  13,000-mega- 
cycle band,  since  there  was  not  sufficient 
spectrum  space  available.  In  addition. 
Mr.   Larsen   urged  the   FCC   to   classify 


UNBREAKABLE 


MATIOWAl 


g&ffigrBiSre^S-f^^ 


Jfom 


Ljreetinad    /#*< 

LOCAL  NO.  224 

Washington 
D.  C. 


from 

LOCAL  NO.  548 
Paris,  Texas 


LjreetinaS    Prom 
NEW  YORK  STATE  ASSOCIATION 

of 
MOTION  PICTURE  PROJECTIONISTS 

Charles  F.  Wheeler,  secretary 
f&tuaana  (fo?titt00 

to  all  from 

LOCAL    NO.    597 
Waco  Texas 


theater  Tv  as  a  separate  non-broadcast 
service. 

On  the  important  question  of  whether 
theater  Tv  could  use  coaxial  cable  or 
wires  for  intercity  or  intracity  transmis- 
sion of  programs,  Mr.  Larsen  stated  that 
at  the  present  time  theater  Tv  would  not 
be  able  to  use  coaxial  cable  or  wire  facil- 
ities of  the  A.  T.  and  T.  because  the 
2.7-megacycle  band  provided  was  insuffi- 
cient. He  estimated  that  approximately 
6-  or  7-megacycle-wide  bands  would  be 
required. 

He  conceded  that  eventually  it  would 
be  more  economical  in  a  city  to  distrib- 
ute programs  by  wire  line,  rather  than 
by  radio,  and  that  eventually  the  common 
carriers  would  have  wider-band  coaxial 
cable  and  wire  facilities.  But  he  felt  that 
for  an  indefinite  period  theater  Tv  would 
have  to  use  radio  for  program  distri- 
bution.8 

Fail  to  Convince  FCC 

The  upshot  of  the  1947  allocation  hear- 
ing was  to  make  no  allociation  in  the 
1000-  to  13,000-megacycle  band  for 
theater  Tv,  even  on  an  experimental 
basis,  and  to  indicate  that  the  experi- 
mental authorizations  in  this  band  for 
operation  on  frequencies  not  allocated  to 
the  service  might  be  "renewed  on  a 
strictly  temporary  basis  for  a  period  not 
to  exceed  one  year  from  February  20, 
1948." 

These  conclusions  were  contained  in 
the  FCC's  report  of  February  20,  1948 
(Docket  6651)  which  stated:  "The  re- 
quirements for  theater  Tv  are  still  not 
sufficiently  clear  to  indicate  the  need  for 
a  specific  allocation  for  its  exclusive  use 
at  this  time.  The  Commission  is  of  the 
opinion,  from  information  now  available 
to  it,  that  a  large  part,  if  not  all,  of  the 
functions  required  by  theater  Tv  should 
be  handled  by  stations  authorized  to 
operate  on  frequencies  allocated  to  the 
use  of  communications  common  car- 
riers0." 

The  FCC  ruling,  however,  has  not  ter- 
minated theater  Tv  experimental  use  of 
radio  frequencies.  Since  November  18, 
1947,  Paramount  has  held  special  tem- 
porary authorizations  for  theater  Tv  relay 
in  the  New  York  area  (in  the  2000-  and 
7000-megacycle  bands)  and  it  was 
granted  two  additional  temporary  author- 


8  Former  FCC  Commissioner  E.  K.  Jett 
asked  Mr.  Larsen  if  any  theater  Tv  was  on 
the  air.  When  Mr.  Larsen  answered  that 
none  was  on  the  air,  Commissioner  Jett, 
pointing  to  the  other  demands  for  the  fre- 
quencies in  the  1000-  to  13,000-megacycle 
band,  stated:  "Apparently,  you  would  want 
all  the  other  radio  services  to  stop  dead  in 
their  tracks  and  wait  for  the  deveopment  of 
theater  Tv  service  until  they  can  go  ahead." 

9  Apparently  the  frequency  bands  16,000 
to  18,000  and  26,000  to  30,000  megacycles 
still  remain  open  for  theater  Tv  experimenta- 
tion, but  the  development  of  these  frequen- 
cies is  in  the  embryonic  stage. 


38 


INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


izations  on  May  4.  1948,  for  use  of  the 
7000-megacycle  band  in  the  New  York 
area.  Likewise,  in  September.  1948,  20th 
Century-Fox  was  granted  an  experimental 
STA  for  the  theater  Tv  relay  in  New 
York  in  the  7000-  and  12,000-megacycle 
bands. 

Theater  TVs  Main  Decisions 

It  is  apparent  from  the  foregoing  dis- 
cussion that  theater  Tv  is  at  the  cross- 
roads. It  must  determine  its  own  future 
by  deciding  four  main  questions: 

1.  Will  theater  Tv  rely  on  radio,  coaxial 
cable,  or  wire  for  intercity  and  intracity 
distribution  of  programs? 

2.  If  radio  frequencies  are  to  be  used  by 
theater  Tv,  does  it  desire  the  FCC  to 
allocate  frequencies  for  the  use  of  theater 
Tv,  or  do  the  theaters  expect  to  use  the 
frequencies  allocated  to  "Common-Carrier 
Fixed  Circuits,"  relying  on  the  existing 
common  carriers  to  provide  service? 

3.  If  radio  frequencies  are  needed,  and 
theater  Tv  is  not  content  to  rely  on  the 
services  of  established  common  carriers, 
what  steps  should  it  take  to  obtain  the 
use  of  such  frequencies? 

4.  If  theater  Tv  is  to  use  common-carrier 
radio  coaxial  cable  and  wire  lines,  what 
steps  should  it  take  to  obtain  the  use  of 
such   facilities? 

'Public  Convenience,  Necessity9 

If  theater  Tv  groups  decide  to  apply 
to  the  FCC  for  allocation  of  radio  fre- 
quencies, or  for  authorization  as  a  Tv 
common  carrier,  they  must  sustain  the 
burden  of  convincing  the  FCC  that  a 
grant  of  their  requests  will  serve  the 
public  interest,  convenience,  or  necessity. 
In  meeting  this  burden,  theater  Tv  must 
establish  to  the  satisfaction  of  the  FCC: 

1.  That  the  service  requires  the  use  of  radio 
frequencies,  and  that  coaxial  cable  and 
wire  lines  will  not  provide  a  practical 
substitute. 

2.  That  the  frequencies  requested  are  not 
more  urgently  needed  by  other  radio  serv- 
ices, particularly  those  necessary  for  the 
safety  of  life  and  property. 

3.  That  there  is  a  substantial  public  need 
for  the  service,  and  a  strong  likelihood 
that  the  service  will  be  established  on  a 
practical  working  basis. 

In  prior  appearances  before  the  FCC, 
theater  Tv  has  not  met  the  burden  of 
proof  in  these  matters.  It  seems  clear  that 
another  attempt  to  secure  FCC  authoriza- 
tion of  the  service  and  allocation  of  fre- 
quencies should  be  preceded  by  active 
steps  by  the  motion  picture  industry  to 
obtain  quantitative  data  on  the  public 
acceptance  oi  theater  Tv,  and  to  obtain 
definite  commitments  from  qualified 
groups  in  as  many  areas  as  possible  to 
the  effect  that  they  have  positive  plans 
to  institute  the  service  at  an  early  date. 

Active  Experimentation  Essential 

Data  obtained  by  actual  experimenta- 
tion with  a  multiple-addressee  theater  Tv 
system  would  be  advisable.  A  clear  indi- 
cation of  how  theater  Tv  would  serve  the 
public  interest  is  essential.  In  the  latter 


connection,  it  is  suggested  that  a  mul- 
tiple-addressee system,  serving  not  only 
privately-owned  theaters,  but  rendering 
service  on  a  public-service  basis  to  local, 
religious,  educational,  and  governmental 
groups  in  the  area,  could  present  a  strong 
showing  of  service  to  the  public. 

Tv  broadcast  stations  are  not  available 
in  sufficient  numbers  to  make  possible 
their  ownership  by  any  substantial  num- 
ber of  religious,  educational  or  civic 
groups.  Theater  Tv  potentially  is  one 
means  whereby  such  public  service  organ- 
izations may  participate  directly  in  the 
wonders  of  Tv. 

On  June  30,  1949,  the  FCC  addressed 
letters  to  Paramount,  20th  Century-Fox, 
and  the  SMPE,  inviting  statements  to  be 
submitted  by  September  2,  1949,  con- 
cerning theater  Tv.  Without  limiting  the 
scope  of  the  statements,  the  Commission 
requested  expression  of  views  covering 
six  specific  subjects: 

1.  What  the  minimum  frequency  require- 
ments would  be  for  a  nation-wide,  com- 
petitive theater  Tv  service; 

2.  What  specific  frequency  bands  you  would 
propose  to  be  allocated  to  a  theater  Tv 
service;    reasons  therefor; 

3.  The  exact  functions  which  would  be  per- 
formed in  each  such  frequency  band  in 
a   theater  Tv  service; 

4.  Whether  and  to  what  extent  such  func- 
tions could  be  performed,  in  whole  or  in 
part,  by  use  of  coaxial  cable,  wire,  or 
other  means  of  transmission  not  using 
radio  frequencies; 

5.  Whether    and    to    what    extent    existing 


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CAMERAMENS'    LOCAL    NO.   659 
I.   A.   T.   S.    E. 

Hollywood,   Calif. 

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For  perfect  rewinding  on  2000-foot  reels. 

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INTERNATIONAL  PROJECTIONIST     •     DECEMBER  1949 


39 


c6miiion  carriers  have  or  propose  to  have 
facilities  available  capable  of  performing 
such  functions,  in  whole  or  in  part,  by 
radio  relay,  coaxial  cable,  or  wire; 
Plans  or  proposals  looking  toward  the 
establishment  of  a  theater  Tv  service. 
To  make  theater  Tv  economically  fea- 


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permits  burning  every  inch  of 
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save  $50,000.00  a  year. 

Available  for  these  H.I.  trims: 
Negatives  Positives 

6  mm.  x  9"     7  mm.  x  12"  and  14" 

7  mm.  x  9"  8  mm.  x  12"  and  14" 
and  13.6  mm.  x  22"  (machined 
for  adapters)  to  provide  20  min- 
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Shipped  PREPAID  at  regular  car- 
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sible  it  may  be  necessary  for  numbers  of 
theaters  in  a  city  to  join  together  in 
co-operative  groups.  Since  these  groups 
in  ail  likelihood  will  find  it  necessary  to 
qualify  as  licensees  of  radio  facilities, 
and  possibly  as  common  carriers  of  Tv 
programs,  it  is  important  that  these  co- 
operative groups  be  owned  and  organ- 
ized to  comply  with  the  licensing  require- 
ments of  the  Communications  Act  and 
the  FCC.10 

Organizing  Co-operative  Groups 

An  example  of  a  co-operative  organiza- 
tion that  is  operating  in  the  common- 
carrier  field  with  FCC  sanction  is  Press 
Wireless,  Inc.  This  corporation  was  or- 
ganized in  1929,  with  its  stock  held  pri- 
marily by  newspaper  and  news  associa- 
tions. It  has  been  licensed  or  authorized 
by  the  FCC  to  engage  in  various  forms 
of  communications,  including  program 
transmission,  radiophoto,  facsimile,  and 
message  telegraphy.  It  conducts  a  public- 
press  service  on  a  multiple-addressee 
basis,  transmitting  news  items  and  other 
material  intended  for  publication  by 
press  agencies  and  newspapers. 

Similarly,  a  theater  Tv  group  might  be 
organized  to  provide  a  limited  common- 
carrier  service  to  theaters,  educational, 
and  public-service  organizations. 

10  Currently  the  FCC  is  studying  the  effect 
of  the  decision  of  the  United  States  Supreme 
Court  in  United  States  versus  Paramount 
Pictures,  Inc.,  et  al.,  334  U.  S.  331,  upon  the 
qualifications  of  the  major  motion  picture 
companies  to  hold  broadcast  and  Tv  licenses. 
In  that  case,  Paramount,  Twentieth  Cen- 
tury-Fox, Warner  Brothers,  Loew's,  Inc.,  and 
Radio-Keith-Orpheum  were  found  to  have 
violated  the   Federal   antitrust  statutes. 

[NOTE:  The  third  and  final  installment  of 
this  series  will  discuss  the  outlook  for  color 
Tv  and  will  also  consider  the  extremely  in- 
volved problem  and  as  yet  pratically  neglected 
programming   for  theater  Tv. — £D.] 


(ssSr*!Sr<*?aiSrW^^ 


Ljreetinai    Pr 


rom 


LOCAL  NO.  488 

Harrisburg 
Penna. 


ttmtmga  . . . 

LOCAL  NO.  678 
I.    A.    T.    S.     E. 

Laredo,  Texas 


Ifolt&ag  <£mtttt00  torn 

Moving  Picture  Operators' 
Protective  Union 

LOCAL   NO.   181 

Baltimore  Maryland 

{^ompliments    of    the 

Officers  and  Members  of 

PROJECTIONISTS'  LOCAL  NO.  162 
San  Francisco,  Calif. 


<&rMttt0!S  trt  all 
From  a  Growing  IP  Booster 

OUR  THANKS 

For  a  Service  Well  Given 

• 
LOCAL  NO.   170-A 
I.    A.    T.    S.    E. 

Greater  Kansas  City 


GREETINGS 
and  Best  Wishes 

LOCAL  NO.  415 
I.     A.     T.     S.     E. 


TUCSON 


ARIZONA 


from 

LOCAL  NO.   10 
I.    A.    T.    S.    E. 

Buffalo,  N.  Y. 


C.  W.  SHILKRETT— Owner,  Rex 
Theatre,  Joplin,  Missouri — says: 
"No  exhibitor  can  afford  to 
operate  a  theatre  without  RCA 
Sound  Service." 
To  get  the  benefits  of  RCA  Service — 
write:   RCA  SERVICE   COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


40 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


GEORGE  EASTMAN 

(Continued  from  page  28) 

with    the    possibilities    of    the    dry-plate 
process. 

Taking  a  formula  from  the  Journal, 
Eastman  started  to  make  gelatin  emul- 
sions. He  said  that  at  first  he  wanted  to 
make  photography  simpler  merely  for 
his  own  convenience;  but  soon  he 
thought  of  the  possibilities  of  commer- 
cial production.  By  June,  1879,  he  was 
not  only  making  plates  which  were  en- 
tirely successful,  but  he  built  an  appar- 
atus for  coating  them.  This  he  patented 
both  in  the  United  States  and  in  Europe. 

Kodak's  Turbulent  Beginnings 

In  April,  1880.  Eastman  started  to 
manufacture  dry  plates.  Difficulties  were 
met  and  overcome;  utter  collapse  was 
faced  at  least  once;  but  within  a  few 
years  plates  were  being  manufactured 
on  a  commercially  profitable  basis,  and 
Eastman  was  about  to  turn  his  attention 
to  the  development  of  new  products. 
His  experiments  were  directed  to  the 
use  of  a  lighter  and  more  flexible  sup- 
port than  glass. 

The  first  thing  he  tried  was  the  use 
of  paper  to  carry  the  emulsion,  the  pa- 
per being  in  the  form  of  a  roll  carried 
in  a  roll  holder  which  was  used  in  the 
ordinary  view  cameras  in  the  same  way 
as  the  holders  for  glass  plates. 

The  first  film  advertisements  stated: 
"Shortly  after  January  1,  1885,  the  East- 
man Dry  Plate  and  Film  Company  will 
introduce  a  new  sensitive  film  which  it 
is  believed  will  prove  an  economical  and 


convenient  substitute  for  glass  dry  plates 
both  for  outdoor  and  studio  work."  This 
system  of  photography  by  roll  holders 
fitted  into  the  existing  apparatus  and 
was  immediately  successful,  but  the  pa- 
per was  not  satisfactory  as  a  carrier  for 
the  emulsion  because  the  grain  of  the 
paper  was  likely  to  be  reproduced  in 
the  print. 

Eastman  then  tried  to  substitute  a  film 
of  collodion  for  the  paper,  but  he  couldn't 
make  a  collodion  film  from  the  solu- 
tion of  nitrocotton  in  ether  and  alcohol 
which  was  strong  enough  to  carry  the 
emulsion,  so  he  coated  the  collodion  on 
paper  to  get  strength,  then  coated  the 
emulsion  on  the  collodion,  and  used  this 
material  after  exposure  and  development 
by  stripping  from  the  paper  the  collo- 
dion and  gelatin  carrying  the  image. 

First  Kodak  in  1888 

To  reach  the  general  public,  Eastman 
decided  to  make  a  new  kind  of  camera, 
which,  introduced  in  June  1888,  was  the 
first  Kodak.  It  was  a  box-type  of  cam- 
era, light  and  of  small  size,  loaded  with 
a  roll  of  stripping  paper  of  such  length 
as  to  provide  for  100  exposures.  The 
price  of  the  camera,  loaded  and  includ- 
ing a  shoulder  strap  and  case,  was  $25. 
After  exposure,  the  camera  had  to  be 
sent  to  Rochester,  where  the  exposed 
strip  was  removed  and  developed  and  a 
new  one  inserted  at  a  charge  of  $10. 

This  was  a  radical  change  in  policy. 
The  roll  holder  had  fitted  into  the  exist- 
ing system  of  photography.  The  Kodak 
created  an  entirely  new  market  and  made 


W  BRILLIANT  PICTURE*. 

ON  LARGE 

WVE-W  SCREENS 


06&!«$^ 


Wit: 


Rtf*- 


Operating  at  85  amperes,  the  Motiograph-Hall  produces  19,000 
lumens — more  light  than  condenser-type  high  intensity  lamps 
operating  at  more  than  twice  this  amperage. 

A  rotating  positive  carbon   (an  exclusive  feature)   permits  even 
burning  of  the  carbons  and  a  proper  crater  form. 
Automatic  focus  control  holds  the  crater  of  the  positive  carbon  at  the  exact  focal  point 
of  the  mirror. 

The  carbons  used  cost  about  one-third  that  of  the  larger  carbons  employed  in  condenser- 
type    lamps   operating   in    the    140-180   ampere   range. 

Other  Motiograph  products:  1  K.W.  and  46-ampere  high  intensity  arc  lamps,  projectors, 
sound  systems,  motor-generators,  in-car  speaker  equipment  and  junction  boxes,  ramp  switch- 
ing panels  for  drive-ins,   turntables,  etc. 

See  your  Motiograph  dealer  for  a  demonstration  or  write  tor  literature. 


mOTIOGRflPH,  MC 


4431    W.   LAKE  STREET,      CHICAGO   24,   ILLINOIS 
Export  Division    (Except  Canada)     Frazar 
301    Clay  Street,  Si 


photographers  of  people  without  any 
special  knowledge  of  the  subject,  their 
only  qualification  being  the  desire  to 
take  pictures.  Anybody  could  buy  a 
Kodak,  "press  the  button,"  and  Mr. 
Eastman's  company  "would  do  the  rest." 
Modern  photography  started  with  the 
Kodak. 

While  the  Kodak  was  being  developed, 
Eastman  continued  his  attempts  to  get 
rid  of  the  paper  base.  Solutions  of  nitro- 
cotton in  various  solvents  eventually  pro- 


The  first  major  screen 
improvement  in  30  years! 


CYMAMIC 

Custom  Screen 


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10S  ANGELES  •  PORTLAND  •  SEATTLE  •  SAN  FRANCISCO 
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Exclusive  Export  Distributors 
FRAZER  &  HANSEN,  Export  Division 

301   Clay  Street,  San  Francisco  11,  California 


•   •  • 

#ea0mt'fi  (&twtin$&  from 

SETH  BARNES 

ERNEST    DINSMORE 
BOB  HEAGLER 

CHARLIE     HEDGES 
FRANK   HELGESON 

JOE  HUGHES 
EMMETT    JEFFRESS 

LEE   KICKEL 
ARTHUR   LEE 

ALBERT  McLAIN 
ALBERT  McBRIDE 

ARTIE    MURPHY 
ROY  MURPHY 

CHARLES  PECK 
IVAN  PHILLIPS 

JOHNNY  SMITH 
"JAKE"  SWART 

HARRY    SWIM 
BOB  TROUSDALE 

GENE  WATKINS 
"DUTCH"   WATKINS 

FRANK   WELSH 
CHARLES    WINSLOW 

LOCAL  NO.  414 
WICHITA,  KANSAS 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


41 


ARTHUR  SCHOENSTADT— 
President,  H.  Schoenstadt  &  Sons, 
Chicago,  Illinois — says: 
"RCA  Service  has  always  been  of 
top  Iquality.  It|  has  insured  us  of 
the  highest  caliber  of  workman- 
ship. It  has  been  a  great  aid  in 
keeping  our  theatres  at  the  maxi- 
mum of  efficiency." 
To  get  the  benefits  of  RCA  Service — 
write:   RCA  SERVICE   COMPANY, 
INC.,  Radio  Corporation  of  America, 
Camden,  N.  J. 


duced  a  sheet  of  film  base  which  had 
the  necessary  strength  and  flexibility. 

In  August  1889,  the  first  transparent 
film  in  rolls  was  marketed.  This  film 
was  first  made  by  spreading  a  solution 
of  nitrocellulose  on  a  glass  table  200 
feet  long  by  42  inches  wide  (made  up 
of  10  glass  plates  20  feet  long  joined 
together  at  their  ends)  which  when 
dried  was  first  coated  with  a  "sub- 
stratum" of  silicate  of  soda  to  make  the 
emulsion  adhere  to  it,  and  then  coated 
with  gelatin  emulsion. 

The  advantages  of  this  nitrocellulose 
film  over  the  "stripping"  film  were  that, 
as  it  was  transparent  and  grainless,  it 
could  remain  as  the  permanent  support 
for  the  negative,  thus  avoiding  the  paper 
base  and  the  stripping  operation,  also 
producing  better  results  in   printing. 

In  1891  the  amateur  transparent  film 
was  further  improved  by  making  it  day- 
light-loading. This  was  accomplished 
by  winding  it  on  a  wooden  core  inside 
a  light-tight  box  and  attaching  black 
cloth   leaders   to   the    ends   of   the   film. 


WENZEL 

Time-Tested 
Theatre  Equipment 

PRO-31  has  !4"  more  space 
between  reel  and  rear  wall 
of  magazine,  preventing 
scratching  of  the  magazines 
due  to  bent  reels. 

Send   for  descriptive 
literature. 

WENZEL 

Complete      pR0JECT0R    C0 

2505-19  S.  State  Street 
Chicago  16,  III. 


PRO  -  31 
De  Luxe  Deeo  Case 


?§t»a'^w«K»^w^^ 


S^eaAon  5    \-jreeiina6 
and   dS est    l/Uidned 

LOCAL  NO.  521 

Long  Beach,  Calif. 

MOTION  PICTURE  PROJECTIONIST 

LOCAL  NO.  486 

Hartford,  Conn. 


(/Jedt    lA/idhed 

LOCAL  NO.  396 

Binghamton,  N.  Y. 

— from — 

LOCAL  NO.  348 

Vancouver,  B.  C. 


ift^JiSsMSsiM^ 


Later,  it  was  wound  inside  a  protective 
sheet  of  black  paper  with  a  sufficient 
overlength  of  the  paper  so  that  the 
camera  could  be  loaded  as  it  is  today, 
without   endangering   the   sensitive   film. 

In  1895  the  first  Pocket  Kodak  was 
designed.  The  first  lot  of  these  cameras 
manufactured  amounted  to  25,000;  and 
in  1898  a  further  improvement  in  cam- 
eras was  made  in  that  they  were  made 
collapsible.  The  first  of  these  was  known 
as  the  "Folding  Pocket  Kodak."  In 
1900  the  first  Brownie  camera,  intended 
for  children,  was  put  on  the  market  at 
the  price  of  $1. 

The  development  of  roll  film  photog- 
raphy produced  a  situation  very  differ- 
ent from  that  which  had  existed  previ- 
ously. Until  the  coming  of  the  Kodak 
and  Brownie  cameras,  the  photographer 
had  been  a  more  or  less  skilled  crafts- 
man: he  developed  his  own  negatives 
and  made  his  own  prints  and  was  per- 
force interested  in  the  technical  aspects 
of   the    subject. 

The  new  photographers  using  the 
simple  roll  film  cameras  no  longer 
troubled  in  the  least  about  the  technique 
of  photography  nor  were  they  interested 
in  its  craftsmanship:  they  were  con- 
cerned only  to  get  photographs  of  sub- 
jects which  interested  them.  The  manu- 
facture of  film  developed  as  an  industrial 
operation ;  while  the  finishing  of  the 
pictures  was  undertaken  by  thousands  of 
small  establishments  all  over  the  world 
who  could  collect  the  rolls  of  exposed 
film  and  develop  and  print  them  for  the 
photographer. 

In  1923,  Kodak  introduced  16-mm 
film,  and  the  process  of  amateur  cine- 
matography associated  with  it.  This  in- 
troduction was  exactly  akin  to  the  in- 
troduction of  the  Kodak.  The  film  was 
supplied  ready  to  be  loaded  in  daylight 
in  a  convenient  portable  camera  and 
after  exposure  was  returned  to  Kodak, 
which  developed  the  film  by  a  reverse 
process  to  make  a  picture  ready  for  pro- 
jection in  the  home.  Taking  motion  pic- 
tures in  1924  was  no  more  difficult  than 
taking  pictures  in  the  Kodak  in  1889. 

George  Eastman,  anxious  to  see  a 
similar  development  in  color  photog- 
raphy, ordered  work  on  many  processes. 
The  Kodakcolor  process,  introduced  in 
1928  for  16-mm  pictures,  came  nearest 
to  meeting  his  requirements;  but  when 
the  problem  was  finally  solved  by  the 
introduction  of  the  Kodachrome  process 
in  1935,  George  Eastman  was  no  longer 
here  to  see  it. 

Photography  owes  its  existence  and 
progress  to  "amateurs."  Fox  Talbot, 
Scott  Archer,  R.  L.  Maddox,  George 
Eastman — all  became  interested  in  the 
taking  of  pictures  and  in  pursuit  of  their 
hobby  worked  out  the  improved  proc- 
esses and  methods  which  are  the  mile- 
stones of  photographic  technique. 


42 


INTERNATIONAL  PROJECTIONIST 


DECEMBER  1949 


SO  MUCH 


for  so  LITTLE 


$0.00 


3 


per  copy 
postage  prepaid 


Every  projectionist  should  know  the  whys  and  where- 
fores of  his  projection  room  equipment.  He  should 
know  what  to  do  and  what  not  to  do  when  his  equip- 
ment fails  to  function  properly,  and  how  to  keep  the 
show  going  until  the  service  inspector  arrives  at  the 
theatre.  PROJECTIONISTS'  SERVICE  MANUAL  is  a 


complete,  compact  compilation  of  everyday  problems 
encountered  in  the  projection  room,  and  contains 
sound  practical  suggestions  relating  to  their  causes 
and  how  to  remedy  them.  All  items  are  grouped  ac- 
cording to  classifications,  and  many  of  them  are 
illustrated  with  schematic  diagrams. 


A  copy  of  this  valuable  trouble-shooter  should  be  in  every  projection  room  for  in- 
stant reference  and  as  a  trouble  guide.  Many  I.  A.  Local  Unions  have  placed  a  copy 
of  this  manual  in  each  projection  room.  The  price  is  right  —  only  $3  per  copy, 
postage  prepaid. 


S&nd  #da  ii  Wdw! 


(Do  Thi  (Dsdaif 


f       INTERNATIONAL  PROJECTIONIST 

]       19  West  44  Street.  New  York  18-  N.  Y.                                                                                                                                                                | 

i       Gentlemen:  Enclosed  find  S3.00  for  a  copy  oi  PROJECTIONISTS'  SERVICE  MANUAL,  postage  prepaid. 

i                   -,---...........».......                           ......... 

.     ■'■■  .  :Ufi 

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be  a  wise  old  bird  .  .  .  wait  'til  February.  .  .  the  wraps  will  be  off! 


T.  M.  REG.  U.S.  PAT.  OFF. 
DISTRIBUTED      BY      NATIONAL      THEATRE      SUPPLY 


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