THE LIBRARY
THE FIELD ARTILLERY SCHOOL
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"A WINTER AFTERNOON"
J. S. Neary, Trenton, N. J.
Complete ^eirSnjJtructing Hfbrar^
of $mctical ^i^otogmpi^t
VOLUME II
Negative Developing
and After-Manipulation
Including
Development of Films and Plates, Intensifying, Reducing ;
also Ammonia, Factorial and Tank Development.
Wet Plate and i^rotype Processes
J. B. SCHRIEVER
Editor-in,' Chief
PUBLISHED BY
^Imetuan ^S^c^ooi of %xt anii f^|)otograp|)p
SCR ANTON, PA., U. S. A.
1909
Copyright, 1908, 1909, bt
AMERICAN SCHOOL OF ART AND PHOTOGRAPHY,
ScRANTON, Pa., U. S. a.
£ntbred at Stationbrs' Hall, London, England.
All rig^bts and translations reserved.
SRLF
liRL
5140616
TABLE OF CONTENTS ^-^
VOLUME II.
CHAPTER I. PAOB
Dry Plate Developing 9
Introduction 9
Brief General Instruction 10
CHAPTER II.
Dry Plate Developing — Detail Instruction 13
CHAPTER III.
Difficulties — Dry Plate Developing 39
CHAPTER IV.
Developing Under-Exposures 49
Difficulties 57
CHAPTER V.
General Negative Intensifying 63
Difficulties 70
CHAPTER VI.
Local Intensifying 73
Difficulties 76
CHAPTER VII.
Developing Over-Exposures 81
CHAPTER VIII.
Difficulties — Developing Over-Exposures 91
CHAPTER IX.
Advanced Development of Over-Timed Plates.... 99
CHAPTER X.
General Negative Reducing 105
CHAPTER XI.
Local Reducing 121
Difficulties 127
(V)
vi CONTENTS
CHAPTER XII.
Universal Developing 131
Difficulties 140
CHAPTER XIII.
Special Pyro Developing for Commercial Photog-
raphy 143
CHAPTER XIV.
Special Developing of White Drapery Portrait
Negatives 153
Difficulties 161
CHAPTER XV.
Hydroquinone and Eikonogen — Non-Staining and
Non-Poisonous Developer 165
CHAPTER XVI.
Metol-Hydroquinone and Metol-Adurol — Combined
Developer for Negatives and Lantern Slides 171
CHAPTER XVII.
Ammonia Developing 179
CHAPTER XVIII.
Factorial Development 185
Difficulties 198
CHAPTER XIX.
Tank or Stand Developing 20J
Difficulties 220
CHAPTER XX.
Tank Development for the Professional 224a
CHAPTER XXI.
Special Instruction for the Manipulation of
Different Brands of Plates 225
Part I — Cramer Plates 226
Part II — Seed Plates 252
Part III — Hammer Plates 279
CHAPTER XXII.
Wet Plate Process 301
CONTENTS vii
CHAPTER XXIII.
Difficulties — Wet Plate Process 323
CHAPTER XXIV.
Wet Plate Photography for the Photo-Engraver. 327
CHAPTER XXV.
Ferrotype Process 333
CHAPTER XXVI.
How THE Studies Illustrating This Volume Were
Made 343
Appendix 348
General Index 367
ILLUSTRATIONS
Illus. Par.
Number Title Page Ret.
1 ) Simple Method of Ventilating a Dark-
2 j Room 14 ii
3 Floor Plan of a Convenient Dark-
RooM 15 14
4 Sectional View of Convenient Dark-
RooM 16 15
5 Plate Washing Tank 18 16
6 Section of Dark-Room Used for Bromide
AND Negative Enlarging 21 20
7 Example — Correct Exposure loi 245
8 Example — Over-Exposure Corrected by
Proper Development loi 245
9 Print from Over-Exposed and Over-De-
veloped Negative, One - Half of
WHICH IS Reduced 115 284
r Before and After Reducing 115 284
12 Example of Overcoming Halation in-
Interior Photography 145 364
13 Special Development of White
Drapery 155 390
14 Improved Developing Tank 211
15 Style A Developing Tank 211 512
16 Style B Developing Tank 211 513
17 Gennert Tank 211
18 The Ideal Fixing Tank 211 514
19 Rubber Fixing Tank 211 515
20 Ideal Adjustable Washing Box 211 516
(«)
X ILLUSTRATIONS
Illus. Par.
Number Title Page Rep.
21 B. & J. Developing Tank, Style C 2 24g
22 Eagle Developing Tank 224^
23 Eagle Developing Tank 224g
Eastman Developing Tanks 224/1
24 Lowering Rack of Plates Into Solution
Cup 224/1
25 Loading Plate Into Rack 224/1
26 Placing Septum Over Lower Tier of
Plates 224^
27 Fastening Cover of Solution Cup 224^
28 Silver Bath 304 876
STUDIES AND HOW THEY WERE
PRODUCED
Study
Number Title Author
A Winter Afternoon . . . . J. S. Neary
1 Old Cedars J. S. Neary
2 Woodland Mist Wm. T. Knox
3 Morning Lights and
Shadows J. H. Field
4 At Peace Dr. A. R. Benedict
5 Sheep W. E. Bertling
6 Marine S. I. Carpenter
7 Snow Lights. . . .Geo. H. Sheer, M.D.
8 A Dull October
Day John Chislett
9 Wave Action J. R. Peterson
10 Marine S. I. Carpenter
11 Sand Dune J. S. Neary
12 The Up Hill
Road Geo. H. Scheer, M.D.
13 A ToKio Water-
way Wm. H. Phillips
14 Ocean Waves J. S. Neary
Study
Page
i'rONTIJ
How
Made
Page
sPIECE
25
43
343
61
343
79
343
97
344
119
137
344
159
344
177
345
195
213
345
231
345
249
345
267
346
(a)
CHAPTER I.
DRY PLATE DEVELOPING.
INTRODUCTION.
After the exposure has been made on the plate or film
there is still no visible image, and it is necessary to employ
some means of changing the invisible image to a visible one,
and, in so doing, make it possible to utilize this image as a
means toward an end — which end is the finished print.
The sensitive silver salts in the emulsion of the plate or
film have undergone an invisible change when exposed to
the action of the rays of light — some of the particles have
been affected by the light, while others remain as they were.
It will be found when this exposed plate, or film, is placed
in a solution composed of some oxidizing agent, called a
developer, that a change takes place in the color of these
light affected particles and they are thus rendered visible to
the eye, and may also be built up to form an image varying in
density according to the amount of the light action on the
sensitive emulsion.
White objects, of course, affect the sensitive plate or
film to a much greater extent than dark objects ; therefore,
those portions of the emulsion representing white objects will
be much denser than the sections representing the shadows,
and the degrees of light and shade between these two extremes
(called half-tones) will be represented in that degree in which
they affect the sensitive salts in the emulsion. In a general
way, the developer is the agent which acts upon those por-
tions of a sensitive substance which have been exposed to the
9
10 Library of Practical Photography.
light. One of the most popular, as well as satisfactory, de-
veloping agents is pyrogallic acid ; therefore, the funda-
mental training, which is to receive first consideration, will
embody this developer.
BRIEF GENERAL INSTRUCTION.
1. Apparatus and Material. — It is essential, in order
that accurate results be obtained and that waste material be
reduced to a minimum, that you provide yourself, first with a
room that is totally dark ; a suitable ruby lamp ; a supply of
clear water; four trays; a graduate ; etc.; also the necessary
chemicals for mixing the developing solution, and the fixing
bath. (See Pars. 8 to 13 of the Detailed Instruction on Dry
Plate Developing.)
2. Developing. — Prepare the developing solution ac-
cording to the formula given in Par. 47, and in the manner
described in Par. 49, and place in a graduate a sufficient
quantity of this normal solution to thoroughly cover the plate
or film. Close the dark room door and be sure that all rays
of white or actinic light are excluded from the room. No
light should be in evidence, with the exception of that from
the ruby lamp. The developing tray should be rinsed with
clear water and allowed to drain for a few seconds ; then take
the exposed plate and dust it carefully to remove the dust that
might adhere to its surface. Now place the plate in the tray,
with the film or emulsion side up. Holding the tray in the
left hand, take the graduate of developer in the right hand,
and, beginning at the end of the tray furthest from you, pour
the developer quickly, yet carefully, over the plate, at the
same time drawing the graduate towards you — in this way
there will be an even " sweep" or flow of developer going
over the negative and driving off of the surface of the emulsion
all air. If this manipulation is carefully carried out no
air-bells will form on the surface of the plate. Rock the tray
gently and, although protecting the plate from the direct rays
JDrp Plate Developing. 11
of ruby light, watch for the first appearance of the image,
which in the case of a normal exposure should be from twenty-
five to forty seconds. (Before proceeding with the actual de-
velopment you should read carefully the Detailed Instruction
regarding the Theory of Developing, also the Process of
Developing which follows.)
3. Rinsing. — After the plate has been developed it
should be rinsed in clear water for a couple of minutes in
order to remove all superfluous developer from the emulsion.
The negative is now ready to be fixed.
4. Fixing. — The fixing bath should be prepared previous
to developing, and should be made in accordance to the direc-
tions given in Par. 57. When the plate has been fully devel-
oped and rinsed in water it should be placed in this fixing
bath until all traces of the unacted upon sensitive salts have
been removed. The theory of fixing is very fully described
in Pars. 26 and 27.
5. Washing. — When the plate has been fixed it must
be washed for half an hour either in running water or in six to
ten changes of water. Great care must be given to the final
washing, as it is very essential that not only the hypo be re-
moved but that all chemicals be thoroughly washed out of the
emulsion, so that nothing but the metallic silver image re-
mains.
6. Drying. — The plate should be dried in a draught if
possible, yet be sure there is no dust in the air, for any parti-
cles which come in contact with the gelatine emulsion will
adhere to it. The temperature of the room should not exceed
eighty degrees. It is advisable to have the plate dry in from
two to four hours.
7. Preserving the Negative. — When the negative is
dry it should be placed in a negative preserver (manila envel-
ope) and full data recorded on the outside of the envelope.
Important items which might be included in this data are:
subject, brand of plate, weather conditions, make and speed
of lens, size of diaphragm, exposure, developing agent or de-
veloping formula, and other information of value for future
reference.
CHAPTER II.
DETAILED INSTRUCTION.
DRY PLATE DEVELOPING.
Note to Beginners. — In the following instruction wherever the
word " plate " is used '* film " may be substituted.
8. Dark Room. — The first point to consider in the devel-
oping of the dry plate is the room in which you are going to
develop, commonly called the dark room. This is somewhat
of an erroneous term, as the room must not necessarily be
dark, as the term would imply, but only in a chemical sense.
By a dark room we mean a room which, when the door is
closed, is free from any actinic light. The only light in the
room must be produced by the dark room lamp, or window,
commonly called the ruby light ; a combination of ruby,
orange and yellow, which is non-actinic, but only to a certain
extent. The dry plate of to-day is more or less affected by all
colors. You should, therefore, never place a plate while
changing or developing too near your ruby light. You can
examine your plate occasionally by holding it up close to the
ruby light, but only for a few seconds at a time.
9- Dark Room Light. — Besides the quality, the quantity
of light must be considered. You should always employ arti-
ficial light, as daylight is apt to vary. If you are not going
13
14
Library^ of Practical Photography.
to use a regular dark room lantern, over your sink you should
have a window. In this window place your combination of
ruby, yellow and orange glass. On the outside place a shelf
for the light. On this you can place your lamp or adjust the
gas jet or electric light. This will keep the heat out of the
dark room.
10. Size of Dark Room. — In a professional studio where
a large amount of developing is to be done, the dark room
should be fairly large. It is a mistake to suppose that a small
closet or cupboard will do, as it would be extremely injurious
to the health of those who were compelled to remain in such a
small room for any length of time. For the amateur who
only develops a plate at a time, a small dark room is perfectly
safe and practical ; but in either case the dark room should be
kept perfectly clean and there should be a place for every-
thing and everything in its place.
11. Ventilation. — In preparing a perfect dark room, ven-
tilation should also be considered. There should be an outlet
for foul air at the top of one of the walls. It should be so ar-
ranged that the foul air can be let out without letting in light.
(See Illustration No. i.)
Illustration Nos. i and 2
Simple Method of Ventilating a Dark Room
See Paragraph No. II
Detailed Instruction. 17
There should also be an inlet for the fresh air, and this
may be provided by piercing a number of holes at the bottom
of the door and arranging a hood over them. (See Illustra-
tion No. 2.)
12. Developing Outfit. — The room should contain, be-
sides the sink with a tap above it, a table and several shelves,
four developing trays, one fixing box, one washing box, one
i6-ounce graduate, one 4-ounce graduate, one minim glass, one
hydrometer, one stirring rod ; several large mouthed glass
stoppered bottles, one 64-ounce for sulphite ot soda stock, one
64-ounce for carbonate stock, one 36-ounce for pyro stock and
one 36-ounce to hold old developer, one camel's hair dusting
brush, a pair of scales and negative racks.
13. Chemicals. — The following chemicals are necessary:
Carbonate of Soda, Sulphite of Soda, Hypo-Sulphite of
Soda, Pyro, Sulphuric Acid, Nitric Acid, Red Prussiate of
Potash, Persulphate of Ammonia, Bromide of Potassium and
Bichloride of Mercury.
14. A Convenient Dark Room. — The accompanying
illustration No. 3 gives the floor plan together with the di-
mensions of a very convenient combination dark room. This
room can be used for all the different photographic processes
requiring a room which is totally dark. The size of the room
is 10 x 20 feet. Access to the room is made through a vesti-
bule double door without admitting any light. Both doors
are fitted with heavy spring hinges so that when entering or
leaving, the first door is closed before the second one is opened.
15. Developing Sink. — Space has been allotted in each
section of the room for certain particular work, such as the
loading of the plate holders, developing and fixing plates,
making gaslight prints, making bromide and negative enlarge-
ments, etc. The side of the room including the vestibule en-
trance and the two large sinks on either side is illustrated in
Illustration No. 4.
The sink to the left which is nine feet long, is used for
developing and on account of its size is very convenient for
the general manipulation of plates and films. Across the top
and on a level with the sink is arranged a movable rack
18
Library of Practical Photography.
twenty-four inches long by the width of the sink, upon which
to rest the developing tray while developing. This rack is
made of one-inch square strips.
16. Washing Box. — The washing box for 5x7 and
8x10 plates should be placed in this sink and a very conven-
ient one may be easily constructed of one-inch pine lumber
Illustration No^
A Plate Washing Tank
See Paragraph No. 16
according to the following instructions : — The length of the
box on the inside should be thirty inches, while the width
should be eleven inches. Nine and one-half inches from one
end of the tank place the partition C, Z>, and equally divide
lengthwise the remaining larger section by the partition A,B.
Both sides of this partition, A,J9, should contain grooves
one-fourth inch deep and one-half inch apart and the side of
the box //, Z>, and G, C, should also be grooved as well as
Detailed Instruction. 19
the end jB, jF, and the side of partition C, Z?, which faces the
smaller section of the washing box. There will now be three
divisions, two to accommodate 5x7 or 4x5 plates, and an-
other for 8 x 10 plates. A U-shaped piece of lead pipe, per-
forated on the sides with small holes, should be placed in the
bottom of the tank before inserting the partitions. The pipe
should enter the tank at one end at the point marked Af, and
if properly placed it will come in the center of each of the
divisions made for 5x7 plates. On each side of the pipe is
placed wooden strips for the plates to rest on. On the out-
side of the box at Af, the pipe turns upward and extends a
few inches above the top of the box and is connected to a
faucet with a short piece of rubber hose. (See illustration
No. 5.) In addition to the washing box there are two rub-
ber hypo tanks — for fixing 5x7 or 8 x 10 plates,
17. Developing Light. — The developing light is con-
structed so that the front is bevel shaped, for in this way it
throws the light downward upon the developing tray. The
front of this light has two sliding windows, one contain-
ing ruby glass and a sheet of P. O. paper, while the other
frame is fitted with ground-glass. During development the
ground-glass may be shoved back out of the way and the ruby
light used, but when development is completed the ruby light
frame can be slid back and the ground-glass frame drawn over
in its place and the negative examined by it.
18. Shelving. — A very important item in any dark room
is the proper arrangement of the shelves. These should be
placed in convenient location and each shelf contain certain
articles. For instance, the shelves over the developing sink
should contain the developing solutions and other bottles,
graduates, trays, etc., while the shelving at the end of the
room where gaslight prints, bromide enlargements, etc., are
made, should be reserved for paper and negatives and those
over the changing light for storing dry plates, plate holders,
etc. Always keep the same material on the same shelf and
in exactly the same location so that when you have formulated
this system you will be able to locate any material that you
might desire, even though the room is in total darkness.
20 Librar}) of Practical Photography.
19. Department of Printing and Developing. — On
the right hand side of the vestibule is another large sink over
which is placed a ruby light similar to the one previously men-
tioned. The glass in front of this light is, however, of an
orange color suitable for developing papers, but the window
is fitted in a similar manner to the front of the negative devel-
oping light, so that white light may be admitted when desired.
The developing is done at the left end of this sink, while at
the right hand, in the corner, is placed a large hypo tray
25 X 30 inches in size. This tray is large enough to hold
prints 30x24 i"ches and may be used for fixing bromide
enlargements as well as velox and other developing papers.
Across the narrow end of this room is placed a table three
feet deep. Near the center, and far enough away from the
developing sink, is a thirty-two candle power incandescent
electric bulb, which is operated with a switch and is used for
printing gaslight papers. A tin reflector is placed directly
over the electric bulb. Directly over this light near the ceil-
ing is a ventilating window which may be opened when the
dark room is not in use m order to allow a thorough change
in the atmosphere of the dark room.
30. Enlarging Department. — The side of the room
opposite the developing sinks and the vestibule is shown in
illustration No. 6. This side is shelved and used for storing
dry plates, negatives, etc. It is also used for making bromide
and negative enlargements. Directly opposite the vestibule en-
trance and over the drop-table, is a changing light. Under-
neath this light the plate holders are loaded and unloaded.
The light falls directly upon the plate holder, thus enabling
one to see sufficiently to load and dust the plates. At one side
of the ruby light, under the upper shelf, is a storage box for
5x7 or cabinet size exposed plates. On the front of this box
is a heavy lid attached at the top with a heavy spring hinge,
which keeps the lid closed tightly after placing the exposed
plates in the box In order to facilitate the loading of plate
holders, to the right on the changing shelf are two boxes con-
taining dry plates (taken from their original pasteboard boxes),
^0 '^'^
22 Library^ of Practical Phoiograph\f.
ready to be placed in the plate holders — one box is for 5x7
and the other for 8 x lo plates.
21. Bromide and Negative Enlarging. — When this
side of the room is used for negative and bromide enlarging,
the table employed for changing plates is dropped in order to
make room for the enlarging easel. The enlarging camera
is arranged on the previously mentioned table at the end of
the room. An opening is cut in the partition to admit the
condensing lenses, which are fitted in the wall and the camera
is fitted flush to this partition. The electric arc light used for
enlarging is hung on the outside of the wall and is operated
by a switch from the inside. As the length of the room is
twenty feet, an enlargement of any size can be made.
22. Theory of Developing. — We will next consider the
process of developing and the action of the developer
upon the exposed plate. When you have made your ex-
posure and placed your plate in the developer, the developing
agent builds up and renders the latent image visible. When
the plate was exposed in the camera no visible change took
place on the sensitive surface, still some parts were affected
by the light, while other parts remained unchanged.
23. When the plate is placed in the developer it may
merely change the color of the light affected parts, and
render them visible to the eye, or it may build up an image
on the plate. In other words, the developer is the agent
which exerts an action upon the portions of a sensitive plate
which has been exposed to the light, and has no effect on
the parts which have not been exposed.
24. In the pyro developer the action of the pyro is assisted
by an alkali, such as carbonate of soda. When you expose
a dry plate to the light you have a certain amount of silver
sub-bromide. Immerse this plate in plain pyrogallic acid, and
there will be little or no change, but if a small quantity of
alkali is added, the image will begin to develop and the
plate will blacken rapidly, forming a metallic silver; there-
fore, it is necessary that a certain amount of alkali must be
used in the developing of the plate.
Detailed Instruction. 23
25. The action of the carbonate of soda is to open the
pores of the emulsion. If the action is too rapid (and this
would be the case if too strong or too much carbonate of
soda was used) the pyro would penetrate the emulsion too
rapidly and too deeply, and would then stain the film, and
you would produce a yellow negative. To offset this and
prevent staining, sulphite of soda is added. The carbonate
is termed the accelerator and assists the pyro in developing,
while the sulphite is the preservative of color ; therefore controls
the color of the negative.
26. Theory of Fixing. — The agent universally adopted
for fixing both plates and paper is hypo-sulphite of soda.
A sensitive emulsion of chloride, or iodide of silver, on
which has been formed an image, either with or without the
aid of the developing agent, must pass through this process to
render it indestructible by diffused light. It is true that the
image itself is sufficiently permanent, and it cannot be said,
in correct language, to need fixing. The unchanged silver
salts surrounding it are still sensitive to the light, and tend
to be decomposed in their turn, and so the picture is lost.
It is, therefore, necessary to remove these salts by applying
some chemical agent capable of dissolving them. In order that
a chemical may be employed with success as a fixing agent, it
must produce no injurious effect upon the silver salts which
have been affected by the light. Hypo-sulphite of soda is
employed not only on account of its having these safe quali-
ties, but because it is economical. The fact that the silver
contained in an ordinary fixing bath is present in the state of
hypo-sulphite must be borne in mind, because this salt is lia-
ble to undergo peculiar chemical changes. Iodide of silver is
dissolved by hypo more slowly than chloride of silver, and
the amount eventually taken up is less. This is explained in
the following manner : —
During the dissolving of iodide of silver, iodide of sodium
is formed, and this has the effect of acting as a stop to the
fixing. In other w^ords, it retards the action of the hypo-
sulphite of soda. The time occupied in fixing will, of course.
24 Library of Practical Photography.
vary with the strength of the hypo-sulphite of soda solution
employed.
27. The process of fixing is simply the dissolving away of
the sensitive salt unacted upon by the light. We recommend
the plain hypo bath for the following reasons : The addition
of any acid to the hypo-sulphite of soda may cause chemical
changes. It first displaces the chemical hypo-sulphurous acid
from its combination with soda. This acid begins to decom-
pose, and splits up into the sulphurous acid, remaining dis-
solved in the liquid, and giving the characteristic odor of
burning sulphur. Sulphur which separates in a finely divided
state forms a milky deposit. In other words, sulphurization
has been produced, and a plate fixed in this bath will dis-
color, and the image w^ill probably fade away entirely in time.
It will also harden the emulsion, and it is next to impossible
to doctor successfully a plate fixed in a bath of this kind.
28. Discoloring of Hypo Bath. — A strong fixing bath
should always be used for fixing plates. To more fully under-
stand the reasons for this, let us study the peculiar properties
of this salt (hypo-sulphite of soda). Suppose we were to
dissolve sixteen grains of nitrate of silver in one-half ounce
of water and twenty-four grains of hypo-sulphite of soda in
one-half ounce of water, and then add one solution to the
other. A dense deposit of hypo-sulphite of silver would imme-
diately be formed and rapid changes would take place in this
deposit ; first, white and curdy, next canary color, then a rich
orange-yellow, afterwards a liver color, and finally almost
black. This change is due to the sulphuric acid formed by
the mixing of the silver and hypo-sulphite of soda. The
black deposit is sulphide of silver, the yellow and orange
being in the early stages of decomposition. This will explain
why a plate fixed in a weak hypo bath is sometimes covered
with a brown deposit of sulphide of silver and the hypo
bath discolors so rapidly, whereas if a full strength hypo bath
has been used the plate will be free of the deposit and the
bath will remain clear much longer.
29. When you place your developed plate in the fixing
bath you are carrying a certain amount of silver into the hypo.
•^\-'; ^l\ ■■•./«. .;
Detailed Instruction. 27
If, therefore, your hypo bath is weak the silver in the plate
overpowers the hypo-sulphite of soda and sulphide of silver
is formed and the same chemical action takes place as when
you mix the silver with hypo-sulphite of soda. A strong hypo
bath is, therefore, recommended. The hypo is also more easily
eliminated when a strong bath is used.
30. Developing. — A plate you believe to be properly ex-
posed should be started in a normal developer. A correctly
exposed plate can be completely developed with the solution
of normal developer given in this instruction without any al-
teration whatsoever. It is advisable to always save the last
developer used, pouring it into a large mouthed bottle, placing
a cover over the bottle to protect it from dust and also from
the air. The developer will become discolored, but this need
not alarm you, as it will make no difference for the purpose it
is intended, — that is, the developing of over-exposed plates.
However, it should only be kept from day to day. The devel-
oper which you use once as your fresh normal developer,
should be used the next time as old developer.
31. It is well to use two trays for developing. Into one
tray decant the clear solution of old developer. By clear so-
lution we mean that which is free of particles of film or dirt,
but not clear in color. Add to this one-third fresh normal
developer. The other tray use for fresh normal developer.
32. Restraining Development. — If a plate flashes up
quickly, indicating over-exposure, place it in the tray of old
developer at once, rocking the tray quickly so that the bro-
mide in the old developer, which w^as liberated from the emul-
sion of plates previously developed, will penetrate the plate
at once, and check development. The bromide acts as a re-
strainer, keeps the shadows clear, and allows the highlights
to build up. The plate will develop up much slower in this
bath, as the bromide acting on the shadows permits the high-
lights to build up first. Unless plates are very much over-
timed, we advise using no other means of restraining than
those described above.
33. If you have no old developer on hand, and upon plac-
ing the plate to be developed in normal developer it shows
28 Library) of Practical Photography.
indication of over-exposure, then remove the plate immedi-
ately from this bath and if you have a tap of water, run the
fresh water over the plate quickly and at once drop four to
six drops of a ten per cent, solution of bromide of potassium
into the normal developer. Then return the plate to this tray,
and conclude the development.
34. Bromide Solution. — To make a ten per cent, so-
lution of bromide, dissolve one ounce of bromide of potas-
sium in ten ounces of water. Place this stock solution in
a twelve-ounce bottle with cork stopper, and split the cork
to the center. If it fits too tightly you may cut a little notch
in the side and again insert the cork tightly, and you will find
when the bottle is turned bottom side up, the solution w^ill
drop from the cork very nicely and will be a very convenient
way for measuring the required number of drops quickly.
The bromide of potassium when used in the developer pre-
vents oxydization of silver in those parts of the sensitive
plate on which the light has not acted. For example, the
shadows. It also retards the oxydization on the parts on
which the light has acted. For instance, the highlights,
white draperies, etc., etc. If one is quite sure that a plate is
over-exposed, a drop (or no more than two drops) of bromide
can be added to the normal developer before placing the plate
into it to be developed. This will slightly restrain the shad-
ows and a more brilliant negative will be the result. A plate
placed in a fresh developer, which from the start contains two
drops of bromide, will restrain the plate more than six drops
of bromide if added to the developer after the plate has been
once started in normal developer.
35. Action of Old Developer. — When a gelatine-bromide
plate (dry plate) is exposed to the action of light, the sensi-
tive film undergoes a change, the elements of which it is com-
posed (silver and bromide) lose their affinity for each other and
a state of incipient decomposition is set up. If the exposed
plate is then subjected to the action of a developer, for in-
stance, pyro, and all developers have a reducing power over
modified silver bromide, the action of the light is continued
and intensified by further decomposition of the molecules of
Detailed Instruction. 29
the film impressed by light. This continuing of action con-
stitutes development, and by it the image impressed on the
film is made visible, a dark deposit of silver resulting from
the application of the developing agent in those parts of the
silver affected by light in proportion to the intensity of the
light action. When the developer is too strong, we have a
general reduction of silver over the entire sensitive surface,
resulting in what is commonly called chemical fog. The
bromide in the sensitive dry plate is really bromo-iodide of
silver ; originally it was bromide of potassium and iodide of
potassium, but when they became a part of the nitrate of sil-
ver, they, by decomposition, became bromo-iodide of silver.
36. The principal difficulty, therefore, to overcome in de-
veloping an over-exposed plate is chemical fog. While bro-
mide added to the normal developer will prevent this to a cer-
tain extent, yet the development is prolonged considerably
and the action of even the ruby light upon the plate has a tend-
ency to fog, while if old developer was used (one which has
become thoroughly ripened and which contains bromide lib-
erated from previous plates developed) the color of this devel-
oper over the plate protects it from the continuous action of
the light during prolonged development and with less likeli-
hood of fog. Therefore, the use of old developer is preferable
to normal developer with fresh bromide added.
37. Snap and Crispness. — It is well after a plate has
been developing in the old or restrained developer for some
time, to place it in a fresh normal developer in order to give
snap and more crispness, always being careful to rock the
tray. The rocking of the tray must not be all in one way;
first rock from you, and then from side to side. The action
of the normal developer is apt to be quite rapid ; therefore,
the plate must be watched very closely and when the proper
strength and snap have been obtained, remove the plate at
once and rinse thoroughly and then fix.
38. Under-Exposure. — In case the image appears slowly
and with contrast, shadows remaining clear, highlights
building up slowly, you will readily understand that the plate
is under-timed. Then immediately place it in a tray of plain
30 Library of Practical Photography.
water, cover the tray and allow the plate to remain in the
water for say ten minutes, after which conclude developing
in normal developer. We advise covering the tray so as to
keep not only the light of your ruby lamp from the plate, but
also to prevent the air striking the developer, as this would
have a tendency to oxydize and also change the temperature.
39. Extreme Under-Exposure. — If the plate shows
signs of extreme under-timing, make a new developer weak in
pyro, using one-half the quantity of pyro and the regular amount
sulphite and carbonate of soda and double the amount of
water. In making up a developer with less of the developing
agent, you will prevent the highlights from becoming too
dense and harsh, and the weak developer will give the shad-
ows an opportunity to gain in strength and detail. Conclude
the developing in this bath instead of with normal developer.
Your resulting plate will be clear in detail, with no harsh
highlights.
40. Judging When Plate Is Developed. — The greatest
difficulty in developing a plate is to know just when to stop.
Conditions have so much to do with the proper developing of
a plate that it is hard to state exactly how to tell, under all
circumstances, when to stop developing. A properly timed
plate is fully developed and carried far enough when the
contrast between the highlights and shadows is as you would
desire it, and as it appeared on the ground-glass, taking
into consideration that the plate loses some of its strength in
fixing. Some brands of plates fix out more than others. For
instance, a Seed plate will lose two degrees in a hypo bath,
while others will lose one shade of density ; so when judging
if the plate is fully developed, you must bear in mind the
brand of plate used and develop accordingly.
41. In considering an over or under-timed plate as to when
it is fully developed, you must judge it for the same result as
one properly timed, taking into consideration whatever effect
the over-timing or irregular conditions may have upon it.
Should the plate be slightly over-timed it will thicken
(blacken) up more rapidly than if correctly exposed, and,
therefore, must be carried farther, by allowing to remain in
Detailed Instruction. 31
the developer until the desired contrast — even in a very dense
plate — is visible.
42. If the plate were removed from the developer with an
even density throughout, but with no distinction between
highlights and shadows, and then fixed, while it may be
strong, it will lack the necessary contrast. Sucli plates must,
therefore, be carried to the stage where the contrast between
highlights and shadows is visible even in the most dense
plate. The plate so developed can then be reduced and a
good printing negative made of it.
An over-exposed plate under-developed will appear very
thin and full of detail when fixed, but will have no print-
ing quality, so it must be carried far enough to produce this
result and stopped there.
43. Upon examining the plate (by looking through it,
holding it up to the ruby light) during development, if you
are in doubt as to whether the proper density has been ob-
tained, you can, by looking at the back for the image, see
how far through the film the developer has penetrated. If in
looking through you find the proper contrast and the image
also shows fairly clear on the back, you may know your
plate is sufficiently developed. Do not depend, however, on
looking at the back alone, for m some cases plates will be
fully developed before the image appears on the back at all.
This greatly depends on the thickness of the emulsion, which
varies in different brands and also on the length of exposure.
44. For a plate that is slightly under-timed, necessitating
weak, slow development, the image will appear on the back
at an early stage and more distinctly than in a normal expos-
ure in which the image may show very dimly or not at all,
even when completely developed. You will notice that the
highlights show through the film first, and if in looking
through the plate the details appear weak, continue devel-
opment until they are brought out some on the back.
45- Double Coated Plates. — The beginner invariably
under-develops double coated plates, as the extra emulsion
adds to the general density, misleading one's judgment. For
these plates the factorial method of development described
in paragraphs 459 and 695 is recommended.
32 Library of Practical Photography.
GENERAL NOTES ON DEVELOPERS.
Pyro. — Too much pyro clogs the whites. Too little
pyro : slow development, lack of brilliancy.
Alkali. — Too much alkali: quick development, dense,
flat negatives. Foggy and granular. Too little alkali : slow
development, contrast.
Sulphite. — Too much sulphite: cold, gray tones. Too
little sulphite : warmer tones, inclined towards yellow.
W^ater. — Too much water : thin highlights, plenty of de-
tail but lack of snap and strength. Too little water : more
contrast.
Temperature. — Normal, 65° to 70° Fahr. Higher
temperature, intensity and likely fog. Lower temperature :
flatness, lack of snap.
Drying Negatives. — The warmer and closer the atmos-
phere in which the negative is dried, the more dense it be-
comes. Wherever possible, negatives should be dried with
an electric fan, or under some breeze. The quicker they dry,
within limit, say within a few hours, the finer the grain will
be.
NATURE OF CHEMICALS USED FOR DEVELOPING
WITH PYROGALLIC ACID.
46. Sulphite of Soda. — Transparent crystals, also granu-
lar and dried ( anhydrous ) very soluble in water, two parts
of crystal are equivalent to one part dried (anhydrous or
granular). Chemical action, neutral or slightly alkaline.
Do not confuse sulphite with sulphate of soda.
Carbonate of Soda. — Commonly called washing soda.
Transparent crystals, also granular and dried (anhydrous).
Very soluble in water, two parts of crystals are equivalent
to one part dried (anhydrous or granular). Chemical
action, strongly alkaline.
Pyrogallic Acid. — Developing agent. A white crystal-
ine substance, poisonous, although termed an acid its action
is neutral.
Detailed Instruction. 33
Sulphuric Acid, C. P. — Chemically pure. A colorless,
oily liquid. Commercial sulphuric acid is yellow or brown
and should never be used. Caution : — Never pour water
into sulphuric acid, as this would be most liable to cause an
explosion. Always pour the acid into the water. Coming
in contact with flesh it will burn. Do not confuse sulphuric
acid with sulphurous acid.
Bromide of Potassium. — Colorless crystals, dissolves
readily in water.
Hypo-Sulphite of Soda. — Commonly called Hypo.
(Thiosulphate of Sodium.) Put up in crystals and granular
form, colorless.
Nitric Acid, C. P. — (Chemically pure.) A colorless
liquid of a pungent, suffocating odor, is a powerful dissolvent
of all metallic bodies, and if coming in contact with the flesh
will burn.
47. Pyro Formula. — Stock Solution, No. i :
Water 24 ounces
Pyro I ounce
Sulphuric Acid, C. P 10 drops
Stock Solution, No. 2:
Sulphite Soda, Hydrometer Test 70,
or, if by weight,
Sulphite Soda (crystals) 2 ounces
Water 7 ounces
Stock Solution, No. 3 :
Carbonate Soda, Hydrometer Test 40,
or, if by weight,
Carbonate Soda (crystals) 3 ounces
Water 10 ounces
When making up solutions by weight and anhydrous carbonate or
sulphite of soda is used one-half the amount is required.
The Stock Solutions of Sulphite and Carbonate of Soda
can be made up in any quantity, and they should be kept in
a corked bottle.
48. Anhydrous sodas have no water in their composition ;
therefore, they are twice as strong as the crystal, which has
34 Library of Practical Photography,
water in its composition. It is advisable to use anhydrous,
or if the crystal is used be sure and get pure crystals. Sodas
should be purchased in sealed packages or bottles; never in
loose quantities.
49. To Develop, take one ounce of No. i, one ounce of
No. 2, one ounce of No. 3, and add six ounces of pure water
in cold, and eight ounces in warm season. The action of the
developing agent (pyro) is more rapid in warm than in cold
weather. In warm weather the emulsion softens more readily,
and the action of the pyro is more rapid ; therefore, if the
same strength developer was used in warm as in cold weather
the negatives would thicken up too rapidly, resulting in
harsh, strong negatives. This is overcome by adding more
water to the developer. In cold weather the emulsion re-
mains firmer, and the pyro does not affect it so readily ; there-
fore, it is necessary to use a stronger developer — consequently
less water is used than in warm weather.
Developer should never be used but once, whether one
plate or a batch of plates are developed in a tray. After a
plate or a tray full of plates have been developed, that devel-
oper should be discarded, or poured into the second tray to be
used as a restraining bath. All normally exposed plates
should be started developing in a fresh bath.
In preparing a pyro stock solution, first place the water
in the graduate, then add the sulphuric acid, and last add the
pyro. If the water used is strongly alkali, and the chemicals
were not mixed in the order given, this stock solution would
discolor very rapidly.
50. Proper Color of Plate. — If the plate when fixed is
too yellow, strengthen the sulphite ; if there is a lack of color,
the negative is a blue-gray, reduce the strength of the sulphite
stock solution, but use the same quantity. The proper color
of a plate is of the gray order, with the least tinge of brown.
51. Chemical Action. — Always bear in mind that sul-
phite of soda regulates the color-value in the plate ; carbon-
ate of soda produces detail ; and pyro being the developing
agent, gives strength and contrast. If the plates are yellow
Detailed Instruction. 35
you will understand that the sulphite is not strong enough.
For example, we will say you are using sulphite at seventy
test, and your plates are quite yellow. Strengthen it to
perhaps eighty hydrometer test, all other chemicals remain-
ing as they are. Regulate the color of the plate entirely by
the strength of the sulphite of soda.
52. You will find it rarely, if ever, necessary to change
the strength of the carbonate of soda. If, however, you
find upon testing the water that it is strongly alkaline,
you may find it necessary to change the strength of the
Carbonate Stock Solution, that is, make it weaker. For if
the water you are using is strongly alkaline instead of being
neutral, and the regular amount or strength of alkaline solu-
tion (carbonate of soda) was used, you would have more
alkali than necessary to balance the developer. If there is
too much carbonate (or alkali), you will find the emulsion of
the plate will be rather grainy. In such a case reduce the
strength of the carbonate of soda very slightly, say five de-
grees, and this effect will be overcome. The pyro is used for
strength. If the plate develops contrasty, use less of No. i
(Pyro Stock Solution), but usually the formula given will
need no altering whatever.
53. Use of Hydrometer. — A hydrometer is an instru-
ment for determining the specific gravity of liquids. The
strength of the liquid is determined by the depth to which
the hydrometer sinks in the solution. It has on it a series of
numbers from ten to eighty. When testing the strength of
solution correction must be made for variations in tempera-
ture. If the liquid is cold it may allow the hydrometer to
sink lower and the strength it would register might appear
weaker than it is; if warm, it would be just the reverse. Do
not prepare chemicals by weight ; use the hydrometer for test-
ing them and you will always have uniform results.
54. If chemicals in crystal form should dry to a powder
by exposure to air, the weight would be altered, although the
strength of the original quantity would remain the same; con-
sequently a solution made by dissolving one ounce of the dry
36 Library of Practical Photography.
powder would be stronger than one ounce of crystals in the
same quantity of water. Also chemicals of different brands,
and even of the same brand but procured at different times,
are seldom of uniform strength, and if prepared by weight
instead of by hydrometer test, you will be apt to meet with
frequent failures.
55. Alteration of Formula for Different Brands of
Plates. — The formula for developing given herein will work
well with any brand of plate by following the above direc-
tions. If you are using a brand of plate that will strengthen
quickly use more water. If, on the contrary, you cannot get
the desired strength, reduce the amount of water, thus making
your developer stronger and the developing agent (pyro) will
act more rapidly.
56. For Seed, Standard and Stanley Plates use according
to formula ; for Cramer (more pyro should be used) ten
drams of the Pyro Stock Solution No. i and nine ounces of
water; but for Hammer Plates (use less pyro) only six drams
of Pyro Stock Solution No. i and eight ounces of water.
Sodas remaining the same for all brands of plates.
57. Fixing Bath. — For fixing bath use plain hypo and
water, one pound of hypo to two quarts of water, or testing
sixty by hydrometer, and during hot weather keep the bath
cool. Allow the plates to remain in this bath about twenty
minutes, or about ten minutes after all whiteness (bromide of
silver) has disappeared. Should plates show a tendency to
frill in hot weather, prepare a hardening bath composed of
one-half ounce of ground alum to one pint of water. Imme-
diately after fixing, rinse the plates well and then immerse them
in this hardening bath for one minute, or until the film be-
comes hardened, and transfer them to the washing box. The
hypo bath will discolor after using a few times, but this need
not alarm you, as the hypo bath is good as long as it will fix
plates in a reasonable length of time, say fifteen minutes, and
not stain them. Always rinse your plates carefully before
placing them in the hypo ; otherwise you will be carrying the
developer into the hypo, and this is what causes the discolor-
ation.
Detailed Instruction. 37
58. We advise the use of the best sodas. Do not buy the
commercial goods. Pure crystals, or anhydrous sodas are
the best.
59. Weights and Measures. — When not using the hy-
drometer in making up your solutions, the Apothecaries'
Weight and measures should be used.
Apothecaries' Weight.
20 grains — one scruple 20 grains
3 scruples — one dram 60 grains
8 drams — one ounce 480 grains
12 ounces — one pound 5760 grains
Fluid Measure.
60 minims one fluid dram
8 drams one fluid ounce
16 ounces one pint
8 pints / one gallon
60. Preserving" the Pyro. — The Pyro Stock Solution
should be kept in a tightly corked bottle, using a glass stopper
(if possible, a brown or yellow bottle preferred). If a plain
glass bottle is used, wrap it with dark paper, .and place in a
dark, cool place in your dark room. It should b*e shaken each
day to keep the sulphuric acid thoroughly mixed with the
pyro and water.
61. The formula given herein for developing can be ad-
justed to any class of exposure. By diluting with water for
under-exposure, and by carrying farther in the normal devel-
oper for over-exposure, you have control of the plate under
all reasonable conditions.
n— 3
CHAPTER III.
DIFFICULTIES— DRY PLATE DEVELOPING.
62. Plate Slow in Starting to Develop. — This difficulty you can
overcome by being careful that your developer is not too cold. The
temperature should never be under sixty nor above seventy degrees Fahr.
Insufficient carbonate of soda or too weak carbonate and poor quality of
soda will slow the development. Prepare your sodas by hydrometer
test. Always bear in mind that the carbonate of soda opens the pores
of the emulsion on the plate and allows the developing agent (pyro)
to act ; therefore, if there is no carbonate of soda, or if it is extremely
weak or of poor quality, the plate would develop very slowly. If the
plate refuses to develop at all, you will find you have omitted either the
Carbonate or Pyro Stock Solution. If the plate is extremely under-
timed it will naturally start slowly. (See Chapter IV, Developing
Undkr-Exposures.) Slow developing is not a bad fault, however,
as it is better to have your plate start gradually than to have it start
fast. Starting slowly will enable you to better judge whether your
plate is under or over-exposed, and the slow action of the developer
will enable you to treat the plate before it gets beyond your control.
63. Lack of Detail in Shadows. — If you develop your plate accord-
ing to its exposure you will be able to overcome this difficulty, provid-
ing of course, that the plate is not too badly under or over-exposed.
If your plate is under-exposed and you treat it as such, you will pro-
duce more detail than if you developed it in the ordinary way; but of
course if badly under-exposed you will not be able to get a great deal of
detail in the shadows, no matter how you alter the developer. In case
of an under-exposure, the first thing to consider is how to prevent the
highlights becoming harsh and contrasty, and at the same time produc-
ing detail in the shadows. The developing agent (pyro) must, there-
fore, be weakened. In case of an ordinary under-exposure, simply
transferring the plate into fresh water for ten minutes and then returning
it to the normal developer will generally produce detail in the shadows.
89
40 Library of Practical Photography.
On the other hand, if the plate is badly under-exposed a new developer
should be prepared at once, and this must then be made according to
your instructions on Developing Under-Exposures, Chapter IV,
using only half the quantity of developing agent (pyro), but the same
amount of sodas and double the quantity of water. If the plate is over-
exposed you would naturally think there would be plenty of detail in
the shadows. The exposure has provided this detail, but in over-expos-
ing a chemical fog is produced, and if the plate is not treated as over-
exposed you will produce gray, weak, foggy shadows and there will be
no strength to the detail. A plate of this kind must, therefore, be
developed in a developer which contains a restrainer. Ordinarily, by
transferring a plate from the normal developer to the developer in
which plates had previously been developed, will restrain the shadows
and prevent them from fogging over; but in case of extreme over-
exposure the plate must be specially treated with bromide. (See
Chapter VII, Developing Over-Exposures.) In the instructions for
developing you are told that old developer contains bromide which
has been liberated from the plates which you previously developed ;
therefore, this old developer makes a splendid restrainer.
64. Properly Exposed Plates Developing Slowly. — As already
stated, the first consideration in developing is the temperature of your
developer. If the developer is cold the plate will develop slowly and
thin. If the developer is diluted too much it will develop very slowly
If your carbonate of soda is of poor quality, or if you have not the
proper strength called for, the plate will develop slowly. You must,
therefore, be careful in preparing your developer. See that your sodas
are of good quality. The anhydrous or pure crystals should be used.
Always buy the same brand either in bottles or in sealed packages. An-
other important factor is the temperature of your dark room. If it is
extremely cold the action of the developer will be very slow.
65. Plate Flashing Up Quickly and Darkening All Over at
Once, Detail Very Dim. — When a plate acts like this it is a certain
sign that it is over-exposed, or the entire plate has been fogged (light
struck) before or after exposure.
66. Judging if Plate Is Under- Timed. — If a plate is under-timed
you will have trouble in getting it started in developing. When it
finally does start, the highlights will build up contrasty, but very slowly,
and the shadows will remain clear. In case of extreme under-exposure
the shadows will be almost clear glass. There will be little or no detail.
67. Judging if Plate Is Over-Timed. — If a plate is over-timed the
action of the developing will be very fast. The highlights will develop
rapidly, but will be closely followed by the shadows. The shadows will
fill with detail, then the entire plate will appear to fog over as it were,
and instead of gaining in strength will grow dim.
68. Producing Proper Contrast. — You can only get proper con-
trast by being careful and developing the plates according to their ex-
Difficulties — Dr^ Plate Developing. 41
posure. If over-exposed, treat it as such or you will produce weak, flat
negatives. If under-exposed and you do not treat it as such, you will
produce negatives with too much contrast, strong highlights and no
detail in the shadows.
69. Proper Color. — The proper color of the negative should be on
the gray order with just a tinge of brown. With the proper exposure
and developer prepared according to the instructions, this is the color
you will produce. If the plate is over-exposed, necessitating prolonged
development, the plate will become stained a slight yellow, which, how-
ever, is not objectionable, as it will add strength to the printing quality.
A thin, yellow negative will give a stronger print than one which is a blue-
gray, for if a plate is extremely gray, or blue-gray, it will produce prints
with weak shadows and highlights; a very pretty negative to look at,
but one that will not give a snappy, brilliant print. The printing from
such a negative will be very quick, so quick that the surface of the print
only is affected, and when the print is washed the strength is washed
away, resulting in a weak, mealy picture.
70. Judging Proper Strength. — It is impossible to give any method
by which one could judge absolutely the proper strength of development
under all conditions. Only practice and close observation can teach you
this. The difference in exposure, the lighting, etc., all have some
bearing on the strength to which one should carry the development.
One rule can be followed, however, and that is when the distinction be-
tween the highlights and shadows is as it appeared on the ground-
glass, making due allowance for the fixing, then the plate is fully devel-
oped. There are many ways of judging density. A very convenient
one is to hold the plate before the ruby light and place one finger close
to the film and near the strongest highlight, and when you find the
highest light is as dense as the finger, you can consider the plate of the
proper strength. It is a good practice in developing, when in your
judgment the plate is developed far enough, to try and impress upon
your memory the density of the plate developed, and, after fixing, ex-
amine the plate in daylight by looking through it. If it is too dense or
too thin, you must govern yourself accordingly in developing the next
plate. With this practice you will soon be able to judge the proper
strength of development under all conditions.
71. Judging When Plate Is Fixed.— A plate is generally consid-
ered fixed when all the white or creamy effect has disappeared from the
back of the plate, but even then, it is safe to allow your plate to remain
in the fixing bath ten minutes longer. A plate may appear fixed and yet
not be thoroughly fixed. If your fixing bath is cool and not too old,
you could allow your plate to remain in it for hours and the hypo would
do no harm. There is practically no danger of over-fixing; however,
if the hypo bath is old and warm it would be apt to reduce the plate
and soften up the emulsion so badly that the image on the plate wouIC
42 Librar}) of Practical Photography.
be destroyed, or the emulsion would slide off entirely ; therefore, it is
advisable to renew your hypo bath often.
72. Discolored Hypo Bath. — This need not alarm you, as the hypo
bath is good as long as it will fix the plate in a reasonable length of
time, say twenty minutes, and not stain. Always rinse your plate (both
sides) before placing in the hypo ; otherwise you will be carrying the
developer into the hypo, and this, with the silver in the plate, will cause
the discoloration of both plate and hypo.
73. Mottled Negatives. — Generally caused by allowing the plate to
remain in the developer without agitating. This is more frequently
caused in extremely slow development ; as for instance, when you are
using old developer. Remedy: Obvious.
74. Finger Marks. — Caused by carelessness in handling plate be.
fore developing. Remedy: Never allow the fingers to come in contact
with the film side of the plate.
75. Frilling. — Caused by warm solutions, warm hypo, or warm wash
waters. Remedy: Keep all solutions and wash waters cool. (See
paragraph 57.) Dry your negatives in a cool, well ventilated room so
that they will dry as quickly as possible. Dry the negatives at an open
window, being careful that the sun does not strike the same. Dry with
electric fan when possible.
76. Uneven Development. — Caused by not covering the entire plate
when first pouring on the developer. Parts of the plate that do not
come in contact with the developer will develop slower, and no matter
how long you develop it will show uneven developing. InsufBcient
amount of solution will also cause uneven development.
77. Blisters. — Caused by warm wash waters, warm developer, warm
hypo and washing too long. Remedy: Keep your solutions and wash
waters cool, and do not wash longer than one-half hour in running
water. You must also be careful and see that your carbonate of soda
is not too strong. If stronger than the formula calls for, the film will
soften very readily and you are apt to obtain blisters.
78. Pin Holes and Spots. — These are produced in so many differ-
ent ways that it is impossible to enumerate and describe all of them.
The best way to prevent them is to observe cleanliness in all opera-
tions. Your dark room, graduates, measures and trays which contain
developing solutions should be kept clean. Your camera and plate
holder dusted occasionally. The fixing solution should be filtered to
free it from any sediment, and each plate must be carefully dusted be-
fore placing in the holder and before placing in the developer. The
most common spots are small, round, or nearly transparent, with dark
defined edges. These are caused by air-bubbles adhering to the surface
of the plate when the developing solution is first flowed over it. The
gelatine being hard and the bubbles preventing the alkalies from taking
hold of the emulsion at once, is apt to leave these little air-bells. These
bubbles can be removed by gently passing a tuft of absorbent cotton,
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Dificulties — Dry Plate Developing. 45
thoroughly saturated with developer, over the surface of the plate im-
mediately after it is immersed in the developer.
79. Round Transparent Spots. — May be caused by a drop of bro-
mide solution, or a drop of hypo solution falling on the plate either
before the developer is flowed over or even during development. Jiem-
edy: Never add bromide to the developer while the plate is in the tray;
either remove the plate from the tray and then add the bromide (mix-
ing well), or pour your developer into a graduate and add the few drops
of bromide in the graduate and then pour the developer back over the
plate. Wash the hands carefully after being in hypo, thus avoid carry-
ing any of the solution into the developer.
80. Small Transparent Spots, Triangular in Shape and Irregular
in Size. — These are caused by particles of dust adhering to the gelatine
surface of the plate at the time of exposure in the camera, or by dirt in
your developer or hypo. Remedy: Filter all solutions, dust the camera
and plate-holder and plate, and no spots of this kind will appear.
81. Large Transparent Spots, Triangular in Form and Irregular
in Size. — These are generally caused by a scum which forms on the
surface of old developer, and sometimes on new developer, if after it has
been mixed it is left exposed for some time before using, in the develop-
ing tray, or an open vessel, such as a graduate. When the developer is
then distributed this scum breaks up into small triangular particles, and
it adheres to the surface of the plate, thus preventing the action of the
developing solution. Remedy: Filter such developers immediately
before using.
82. Small Transparent Spots Resembling Little Particles of Lint
and Dust. — These are usually caused by brushing the surface of the
plate hurriedly before placing in the holder. The gelatine film becomes
electrified by the friction and attracts the dust and lint floating in
the surrounding atmosphere. Remedy: Always dust carefully and
slowly; do not press on with your brush too hard; dust only in one
direction.
83. Purple or Dark Opaque Spots, Regular in Size but Comet or
Irregular in Shape. — These are generally caused by small particles of
dry pyro coming in contact with the plate either before or during devel-
opment, or by adding dry pyrogallic acid to the developing solution just
before or while developing. These little particles of undissolved pyro
when coming in contact with the plate will cause opaque spots. Rem-
edy: Never add dry pyro to your developer. Never weigh your pyro
in your developing room, especially just before developing. Sediment
in your hypo bath often causes opaque spots. Iron or rust in the water
used will cause opaque spots. Remedy: Make a new bath. If the
water contains iron or rust, the pyro attacks the rust and is immedi-
ately coated with it, and when this touches the film it will leave
an opaque spot. Remedy: Filter water through two thicknesses of
muslin, tying the muslin over the tap. These spots at times can be
46 Library of Practical Photography.
removed by soaking the plate in water to which has been added a few
drops of nitric acid, being careful not to use too much acid.
84. Yellow Negatives. — Negatives will some times turn yellow in
the final washing. This is attributable to the water. If the yellow is
produced by weak or decomposed sulphite, or decomposed pyro, it will
show just as soon as the plate is fixed. In either case the negatives
should be immersed in a clearing bath. ( For formula, see Chapter
X, on Negative Reducing.)
85. Thin Negatives. — Thin negatives with transparent shadows are
due to under-exposure and can seldom be improved by intensifying.
(See Chapter IV, Developing Under-Exposures). Thin negatives
with foggy detail in shadows are usually the result of over-exposure.
The negatives will be thin in the highlights and will make very
unsatisfactory prints. Diluting developer with too much water will
produce thin negatives. Under-developing will do the same. The
results produced by these different causes are not the same, but the
difference is very slight, so slight that it is not easily described.
Negatives of this kind can be improved by intensifying. (See
Chapter V, Intensifying.)
86. Dense Negatives. — Such negatives are generally obtained by
over-developing, allowing the plate to remain in the developer too long.
Remedy: Soak in hypo for twenty minutes and then reduce. (See
Chapter X, on Negative Reducing.)
87. Parallel Lines on Negatives. — These are generally caused
by too strong a fixing bath and bath not thoroughly stirred before using.
These lines, however, generally occur when plates are fixed in a grooved
box.
88. Part of Plate Stained Yellow. — Caused by plate not being
entirely covered by the hypo.
89. Spots and Streaks Almost Transparent on Plates after Dry-
ing.— Caused by water spattering on the plate when dry, or nearly dry.
90. Granular Negatives, Film Having a Grainy Appearance. —
Caused by using too much or too strong a solution of carbonate of soda.
Rocking tray violently while developing. Extremely slow drying of
plate.
91. Negative Drying too Slowly. — Caused by drying plates in too
warm, too cold, very damp, or poorly ventilated room.
92. Negatives Evenly Developed but Drying Unevenly. — If the
negatives when partly dry are removed to another room which is much
colder, or warmer, or if parts not dry are forced dry by fanning, they
will dry unevenly. The part last dried will be more dense than the first
part.
93. Negatives Full of Dirt and Scum when Dry. — Caused by
dirt in wash water. Remedy: Before placing the negatives in the rack
to dry, wipe carefully with a tuft of absorbent cotton thoroughly satu-
rated with water. Clean your washing box every day.
Difficulties — Dr^ Plate Developing. A7
94. Yellow Negatives, Even with Sodas of Proper Strength. —
Sometimes sulphite of soda when in solution, even though it tests the
proper strength, loses its life by age and becomes worthless ; that is, it
does not have its color preserving quality. An indication of this would
be if the plates were yellow and grainy ; in such cases make up fresh
sulphite. It is best to not use sulphite solution over a week or two
weeks old ; better make up a smaller quantity and renew more often.
CHAPTER IV.
DEVELOPING UNDER-EXPOSURES.
95. It is not the object of this instruction to encourage the
under-timing of plates, but to provide the student with a
means of treating plates which he finds, upon development,
are under-timed. In order to produce the very best results
from plates so exposed, they should be treated according to
these instructions.
96. Upon reading the title of the instruction, the first
question that is likely to arise in the reader's mind is how he is
to know before development that the plate is under-exposed, and
if he does know, why does he under-expose. Under ordinary
circumstances one should aim to fully time all plates. How-
ever, there are occasions when one may find it necessary to
slightly under-expose a plate in order to produce certain re-
sults which could not be obtained were you to give the plate
a longer exposure. This is the case more frequently in land-
scape photography. It will sometimes occur, however, in
making portraits; also when children, especially babies, are
being photographed, and more frequently when using black
backgrounds.
97. In landscape work, for instance, you may be attracted
to a pretty view full of deep shadows and strong highlights,
which make it impossible to expose for the detail in the shad-
ows and not over-time the highlights. While you can over-
come this by cutting the exposure in half, still the plate is un-
der-timed in the deepest shadows and you will have to rely on
the developing to overcome this and make a good negative,
full of detail and with good half-tones.
49
50 Library of Practical Photography.
98. There are also scenes which the inexperienced worker
would consider absolutely impossible to photograph, owing
to their peculiar surroundings, and it is just these circumstan-
ces that attract the eye and make such a view interesting.
The most picturesque scenes are generally the most difficult
to reproduce photographically. We will imagine, for instance,
a small brook, or a creek, located in some deep ravine, with
willows and brush overhanging the greater portion of the
water, perhaps with large trees on either side. A stone or
rustic culvert crosses the stream, and when the sun's rays
fall upon the ripples of water as they roll over the little
pebbles and rocks in the brook, they sparkle like diamonds.
If one could reproduce, photographically, this creation of
Nature the highest attainment of art-photography, as applied
to landscape, would be reached. The picture is there; the
secret lies in the excellence of the view point and the scientific
manipulation of the plate during development. For such a
picture, we must first decide upon the best view point from
which to make it. Raise or lower the camera to retain the
effect of the ripples in the stream. The most rapid plates
must be used, and the speed of the shutter must be equal to
the motion produced by the running water.
99. In the majority of cases a speed of -^ second will be
rapid enough, using an open lens. It [is advisable to use an
open lens, for a small opening would necessitate longer expo-
sure, and stopping down also accents the shadows, makes them
deeper and sharper. The aim, therefore, must be to admit
of as long exposure as possible, and yet retain the principal
point in the view, which in this case is the ripples. The edge
of the brook over-shadowed with willows and shrubbery will
be quite dark, and to secure detail in this portion of the view
would ordinarily require perhaps a full second exposure.
100. The principal point of view^ in this picture (the run-
ning water) cannot be photographed with a time exposure.
We must, therefore, make such an exposure as will produce
the effect desired in this portion of the picture. As men-
tioned above, this will require a speed of about ^ second
with an open lens, to produce the desired effect. It is need-
Developing Under-Exposures. 51
less to state that such a view should be made at a time of
day when the light is the very strongest in the shadows, for
the illumination is weak underneath the willows and shrub-
bery even when the light is strongest. The sunlight which
shines through the leaves is very small in quantity as com-
pared with an open light, and it is simply a matter of utiliz-
ing this quantity of light to the best advantage.
loi . Under-Timing Portraiture. — In portraiture the only
real necessity for under-timing a plate is when photographing
children, especially babies. Many times a very natural,
pretty pose and cute expression of a child may be obtained
if the exposure is made quickly, thereby slightly under-
timing the plate. There are also times when you are apt to
slightly under-time a plate, and not know it. The very best
operators are likely to misjudge photographic color values
and slightly under-time their regular work, Such plates must
be treated and developed entirely different from properly ex-
posed plates and the developing chemicals must be so manipu-
lated as to give you the best results under the circumstances.
I02. Action of Carbonate of Soda. — You may be led to
believe, because carbonate of soda is termed the detail pro-
ducing chemical, and is used in developing to open the pores
of the film, and permit the pyro ( or whatever developing
agent you are using) to build up the detail, that you can un-
der-expose to any extent you please, and the carbonate, if
used in sufficient quantities, will supply all detail required.
Suck is not the case. No chemical will supply detail where
there has not been sufficient exposure to produce it. How-
ever, by the proper manipulation during development you
can obtain all the detail that the exposure has produced, but
such exposures cannot be developed with normal developer.
They must be specially treated as under-timed plates. To
develop in the ordinary way with a normal developer would
give very unsatisfactory results — strong highlights, deep shad-
ows and no detail. By altering the developer according to
the methods given in this instruction, you can retain every
value that is possible from such exposures, and many times
52 Library^ of Practical Photography.
save a plate, which if developed ordinarily would be worth-
less.
103. Developing. — We will first consider the developing
of a plate in which you are certain the deepest shadows are
under-exposed. We will suppose that the subject is a land-
scape study such as we have described. Having made the
exposures, now follow the developing of the plate so as to
produce the best results. The plate without question is con-
siderably under-timed in the most dense shadows, for the
shadow portion of the plate had so little illumination that the
exposure given has hardly produced what little detail was
visible to the eye. Therefore, it is necessary to open the
pores of the film so that the required chemicals may be given
every advantage to act.
104. Chemical Action. — ^Remember the effects of the dif-
ferent chemicals used when making up the developer. Pyro
being your developing agent; carbonate of soda detail produc-
ing agent which opens the pores of the film so that the devel-
oping agent can act, thereby supplying detail; and sulphite
of soda controls the color. Carbonate of soda alone is a
strong alkali, and when used in connection with pyro with-
out any color preserving chemical would give very harsh re-
sults and a yellow negative. Therefore, carbonate of soda
must be combined with a color preserving chemical in order
to retain control of the color of the plate.
105. In an under-exposure it is necessary to open the pores
of the film as much as possible before admitting the develop-
ing agent (pyro) to act; therefore, place the plate in a very
weak accelerating solution composed of carbonate and sul-
phite of soda, using them at the proportionate strength given
in the formula for ordinary developing. Sulphite of soda,
hydrometer test 70; carbonate of soda, hydrometer test, 40.
Take of these stock solutions one ounce of carbonate, and one
ounce of sulphite of soda, add sixteen ounces of water. Soak
the plate in this solution, covering the tray so as to exclude
all light and air. Allow the plate to remain in the solution
for ten minutes, rocking it occasionally so that the accelerator
will act evenly. While the plate is soaking prepare the de-
Developing Under-Exposures. 53
veloper as follows : ( Regular formula for stock solutions
will be found in Chapter II, Dry Plate Developing). —
Of the stock solutions take,
Pyro I dram.
Carbonate of Soda ( 40 hydrometer test ) i oz.
Sulphite of Soda ( 70 hydrometer test) i oz.
106. Add twenty ounces of water, and pour this developed
in a tray. Place the plate in this tray, covering it to exclude
all light and air, being careful that the plate is entirely cov-
ered with the solution, and occasionally rocking the tray to
avoid streaks. Allow it to remain fifteen minutes, when upon
examination you will find the plate has developed slowly, but
not hard. Should the plate not be fully developed, prepare a
new developer exactly like that in which the plates are de-
veloping, and proceed the same as before. Repeat this opera-
tion, renewing the developer every fifteen minutes until the
plate is completely developed.
107. Tank Development. — Another very good way is to
use tank development. This method requires a larger quan-
tity of solution, but several plates may be developed in this
tank at one time. Provide a deep galvanized iron, or better
still, a deep rubber grooved box, a regular hypo faxing box — a
new one of course — one that has not been used for any other
purpose. Fill this tank half full with developer, then add
water to within one inch of the top, and stir well. Then
place the plate, or plates, in this tank, covering it to exclude
all light, and allow plates to remain half-hour, when they
should be completely developed. If, upon examination, they
are not strong enough, allow them to remain in the tank until
fully developed. Owing to the large bulk of solution the
tank developer will last for hours without renewing. See
Chapter XIX, Tank or Stand Development.
108. Action of the Pyro. — The very small quantity of
pyro used in developing under-exposed plates gives the accel-
erator an even opportunity to thoroughly open the pores of
the film. The highlights having been fully timed, or possi-
bly a trifle over-exposed, will naturally develop soft on ac-
count of the small quantity of pyro used. If the regular
54 Library of Practical Photography.
amount of pyro had been used in long development, these high-
lights would clog and become very dense. Having, however,
used only a small quantity of pyro, this will allow for ex-
tremely slow development. Consequently, the plate, instead
of developing hard and contrasty, will be clear in the shadows,
soft in the highlights, and full of half-tones.
109. Developing of Doubtful Exposures Which Prove
to be Considerably Under-Exposed. — Such plates should
be started in normal developer, and as soon as the highlights
appear, if you observe the shadows are holding back, with
practically no detail, and the highlights are building up slowly
but very strong, it is a certain indication that the plate is
under-timed ; so at once place the plate in a tray of plain
water. Owing to the fact that the plates are partially devel-
oped they cannot be placed in the accelerator bath, as given
in paragraph 105, for the accelerator alone after the develop-
ing agent has once been applied would be liable to cause a
chemical fog — therefore the safest treatment is a plain water
bath. Allow the plate to remain in the water for ten or fifteen
minutes, covering the tray so as to exclude all light and air.
While the plate is in the water prepare a new developer,
weak in pyro. Take two drams of your pyro stock solution,
add one ounce of sulphite of soda solution (hydrometer test
70), and one ounce of carbonate of soda solution (hydrometer
test 40), and then add sixteen ounces of water. Remove the
plate from the water, and complete the development in this
bath.
no. If the shadows fail to come up and still lack detail,
it is well to gently press the ball of the hand, or the tips of
the fingers, on the portions that will not develop, permitting
the heat from the hand to warm that part of the plate,
thereby assisting in developing more rapidly. Breathing on
these parts of the plate will also have the same effect.
III. Developing Normal or Slightly Under-Timed
Plates. — Place your plate in normal developer. Just as
soon as the highlights begin to appear, carefully examine the
plate by holding it before the ruby lamp, and if you find that
the shadows are developing slowly, with little or no detail
Developing Under-Exposures. 55
showing in them, the highlights building up contrasty but
slowly, you will at once know that the plate is a trifle under-
exposed. Transfer it to a tray of fresh water, and allow it to
remain for ten or fifteen minutes. You will be surprised to
see how much detail the plate will develop in plain water af-
ter it has been transferred from a developer, in which it has
been developing for a short time. Allow the plate to remain
in the plain water for a few minutes, and when you find that
sufficient detail has been produced in the shadows, return it
to the normal developer. If the plate was over-exposed in-
stead of under-exposed, and should you leave it in the plain
water too long, you would produce a flat negative, often
times producing fog in the shadows. It is, therefore, neces-
sary to closely watch the plate at all stages, whether in the
water or developer, and be certain the plate is either under
or over-exposed before you attempt to alter the developer.
112. We would advise in ordinary developing of white
drapery, where there is red or black hair to contend with,
that you remove the plate from the developer as soon as the
image appears, and hold the plate under the tap, permitting
the water to fall on the hair, or portions you desire to develop
more quickly. A few moments of such treatment helps the
general result considerably.
113. To produce softness in the white drapery itself, place
the plate under the tap just as soon as the image first appears,
allowing the water to fall on the portions which do not
develop freely. This will many times improve the negative.
114. Of course a great deal depends upon the temperature
of the water you are using, also the temperature of the devel-
oper. When developing under-exposures the water should
never be colder than 65° to 70" Fahrenheit. In winter months
the chill should be taken off the water for all exposures,
whether under-timed or fully timed, and should be kept at
about the same temperature as in the summer months. In
cases of developing under-exposures, it is advisable to have
the developer never below seventy in winter, and sixty-five in
summer. Do not attempt to develop under-exposures in cold,
dark rooms. Try to have the temperature of the dark room
II— 4
56 Library^ of Practical Photograph}).
at least sixty degrees. If the dark room is cold the developer
soon becomes chilled, and the action is much slower and will
retard the development of the deepest shadows.
115. In case of warm climates or extremely warm weather,
when the developer being warm is liable to cause the film to
soften and perhaps frill, it is advisable to use an acid harden-
ing hypo bath, prepared as follows:
116. Acid Fixing Bath : —
{A) Water 100 ounces
Hypo 2 pounds
Sulphite Soda (granular) 2 ounces
(B) Water 32 ounces
Chrome Alum 2 ounces
Sulphuric Acid — C.P 2 drams
If by Hydrometer test (A) Hypo test 80° 100 ounces
Sulphite Soda Sol. test 60° 16 ounces
If by Hydrometer test {B) Chrome Alum test 20° .... 32 ounces
Sulphuric Acid C. P 2 drams
117. After the ingredients are thoroughly dissolved, pour
S into A slowly, while stirring A rapidly. This bath re-
mains clear and fixes clean, after long continued use, but
should be replaced as soon as the fixing becomes slow, as the
bath is then exhausted. Allow the negatives to remain in the
fixing bath at least five minutes after the whiteness has disap-
peared. The longer the plates remain in the fixing bath the
less washing will be required, and with the acid bath the film
also becomes harder, and fifteen to twenty minutes washing is
sufficient.
118. A smaller portion of the bath can be made up if one
so desires, but as the larger bulk keeps better, and if one has
considerable developing to do, it is better to make up the full
amount. If only an occasional plate is to be developed each
day, then one-fourth the formula is sufficient, or one may pur-
chase the regular acid hypo put up in small packages, making
sixteen and twenty-four ounce solutions. These stock acid
hypo solutions can be obtained from any supply house.
Developing Under-Exposures. 57
119. Practice Work. — It is advisable to purposely
under-time a few experimental plates under different con-
ditions. The different methods suggested for the treat-
ment of plates under-exposed should be tried one method at a
time. The negatives of first experiments should be dried,
and good solid proof prints made ; the necessary data should
be noted on back of proofs, including date, and stating
whether first, second or third experiment. These proofs
should then be filed for future reference, and further experi-
ments made according to instructions, always being guided,
of course, by results of former experiments. It will not re-
quire many tests of this kind before one becomes familiar with
the appearance of plates in the developer of all exposures, and
can judge instantly how much nursing they require to pro-
duce good negatives, and by instinct apply the proper method.
DIFFICULTIES— DEVELOPING
UNDER-EXPOSURES.
120. Negative Drying with too Much Grain. — This is apt to hap-
pen with plates that have developed slowly. Long, continuous soaking
will soften the film, and cause it to raise from the plate, and when it
dries it will dry with a grain to the film. Another cause is due to pre-
vious soaking in the carbonate and sulphite bath. This opens the pores
to an excess. Plates treated thus should be washed in running water
for no longer than fifteen minutes and dried quickly either by an electric
fan or in a room where there is plenty of air circulating. A good plan
is to dry them at an open window, as this will give a free circulation of
air, but you must be careful that the sun does not shine on the negative
while drying, as the heat of the sun is apt to dissolve the film.
121. Yellow Negatives. — Long soaking in the water; soaking in
the accelerator with insufficient sulphite ; poor carbonate or poor sul-
phite and prolonged development are apt to cause this yellowness.
When the pores of the film have been opened to an extreme the pyro is
58 Library of Practical Photography.
apt to stain. As a general thing in an under-timed plate this yello-w
tint, if only slight, will do no harm, but rather adds strength to the
printing quality. You can remove this yellow by treating with clear-
ing solution, given in the instruction on Negative Reducing,
Chapter X.
122. Plate Developing Only Partly and Then Stopping.— When
the plates are badly under-exposed they will generally act in this man-
ner. By adding a little more carbonate of soda, being careful, however,
not to go to an extreme, the plate will continue to develop. When you
find that the shadows are beginning to fog it is advisable not to attempt
to develop any further, simply rinse and fix the plate. Applying a fresh
developer diluted with four times the amount of water and allowing the
plate to remain in this bath for fifteen to twenty minutes will bring out
all the details possible to obtain with the exposure given.
123. Shadovrs Lacking Detail. — If the plate is very much under-
exposed the shadows will lack detail, no matter how you treat them in
the developer. You can improve them to some extent, however, by
either breathing on these shadows during development — holding the
negative close to the mouth — or laying the fingers on the shadows.
This warmth of the breath or fingers will assist the developer in acting.
You must be careful, however, not to lay the ball of the finger on too
heavily, or it will injure the film. You can improve them considerable
by the treatment given in paragraph 122.
124. Plate Frilling. — If the developer becomes too warm, which
might be the case in a very warm, dark room, or from the continued
placing of the warm fingers in the developer, the plate is apt to frill.
The excessive use of strong alkali (carbonate of soda), is apt to make
the plate soft and frill. Under-timed plates, or plates which develop
slowly, should be handled as little as possible, for the long soaking of
the film'causes it to soften and is, therefore, very easily damaged. See
that your hypo is fresh and cold. After the plate has been fixed, rinse
for a few moments, and place in a weak alum solution — decant half an
ounce saturated solution of alum in ten ounces of water. This will
harden the plate and overcome any frilling. Be sure and use only the
decanted solution, for alum crystals coming in contact with the film
will produce a purple stain. After hardening, wash thoroughly before
setting to dry.
125. Little Blisters Forming on Plate. — Blisters on the plate
should be treated exactly as you would a frilling plate. These little
blisters come from the same source that causes the plate to frill, and if
placed in the alum hardening bath immediately after fixing, the blisters
will be avoided. Should the blisters appear during fixing in the hypo,
then use an acid-fixing bath.
126. Negatives Fogging During Development. — Extremely weak
developer and excessively long development under the ruby light is apt
to fog the plate; also an excessive use of carbonate and sulphite. To
Developing Under-Exposures. 59
overcome this difRculty extreme care must be exercised in regard to the
ruby light, for by long development even the ruby light is apt to fog
the plate. You must also be careful and prevent the air from aflfecting
the developer, which deteriorates, and causes oxydization very rapidly.
A good plan is to have a cover for the tray, being careful, however, to
rock the tray occasionally during development.
127. Negative Flat. — This is generally caused by misjudging the
plate in regard to exposure. If, for example, your plate was only
slightly under-exposed there would be no strength to the highlights,
and the result would be a flat plate. If you find the plate does not gain
strength in the highlights, and appears flat, place the plate in normal
developer. You may even find it necessary to add a little more of the
developing agent (pyro). Over-exposures and under-development will
also produce flat negatives. Such plates can be improved by intensify-
ing. (See Chapter V, on Intensifying.)
128. Negatives Lack Strength and Snap. — When you find that
the plate refuses to build up any stronger in a weak developer, transfer
it to the normal developer for a minute or two, or until you have pro-
duced the proper strength in the highlights.
CHAPTER V.
GENERAL NEGATIVE INTENSIFYING.
129. The object of intensifying is to rectify the misjudg-
ment of exposure and development.
Many times very weak negatives are condemned on ac-
count of their poor printing quality, they being thin, and
printing flat, caused by insufficient developing, under-expos-
ure, or other causes. Many dark room men judge their
negatives by brilliancy, regardless of their printing quality.
The most beautiful appearing negatives do not always yield
the best prints. On the contrary, some apparently poor nega-
tives have the qualities which are essential in producing the
finest prints.
130. A thin negative, if stained brown or yellow, will
have better printing quality than one which is blue; there-
fore, a tinge of brown color is the best. Always judge your
negative for printing qualities alone. There are times when,
through misjudgment, a plate is not developed far enough,
being removed from the developer too soon, resulting in a thin
negative with little contrast between the highlights and the
shadows.
131. Generally, in landscape negatives of this kind, the
sky portion being thin will print gray, and the shadows will
be weak. In portraiture the highlights would be flat. Such
negatives may have the proper color (brownish tint), which
would be to their advantage, yet they lack the snap necessary
to produce strong brilliant prints where all the proper
shades from the highest lights to the deepest shadows will ap-
pear as the eye sees them, with good detail. The remedy for
68
64 Library of Practical Photography.
such a negative is to intensify it, thereby strengthening the
highlights and shadows,
132. In many cases this treatment of the negative im-
proves its printing quality so much that one not knowing
how the negative had been treated would declare that the
prints made before and after intensifying were not from the
same plate. Intensifying is simply increasing the opacity of
a negative. There are many methods employed for this pur-
pose, but two are chiefly used, both being distinct from each
other in the action of the chemicals employed. We will de=
scribe both, but recommend the use of the first.
133. Methods of Intensifying. — The first is simply in-
creasing the density by thickening the deposit of the metallic
silver. The second is by substituting another metal for the
silver, having a more opaque color, causing the negative to
become less transparent.
We recommend the first method, as it is the most simple
to apply, and there is less danger of staining and other fail-
ures.
134. Kind of Negatives Which Can Be Successfully
Intensified. — All weak negatives cannot be successfully in-
tensified, but all can be improved, in some cases, however,
but slightly. The following are the kind of negatives which
can be materially improved by intensifying: Negatives which
are fully timed and under-developed ; negatives which are
slightly under-timed and under-developed, having some detail
in the shadows but lack strength ; negatives which were over-
timed and under-developed, having plenty of detail, but no
strength to the highlights.
135. Intensifying Formula. —
Warm water 12 ounces.
Bichloride of Mercury ^ ounce.
Label this bottle " Poison " Intensifying Solution No. i.
136. Dissolving the Mercury. — The bichloride of
mercury will dissolve very slowly, but by persistent shaking
most of it will dissolve. If particles remain undissolved use
only the clear solution, as one of these small particles coming
in contact with the negative is apt to leave an opaque spot.
General Negative Intensiiy'mg. 65
Clearing Solution No. 2.
Sulphite of Soda, Hydrometer test lo to 12 degrees. ( Or if by weight)
Sulphite of Soda — Anhydrous >^ ounce.
Water 18 ounces.
The exact strength of clearing bath is not essential.
Therefore, for convenience you may use your regular Sul-
phite Soda Stock Solution used for developing, and dilute
it one-half by adding an equal amount of water.
137. Preparing the Plate to Receive the Intensifier.—
To intensify proceed as follows : First, place your plate, or
plates, in running water for at least ten minutes, soaking
the film thoroughly so that the chemicals will effect all por-
tions evenly when applied. Use a tray just large enough to
hold your plate, one that has not been used for any other
chemicals. While your plates are soaking in the water place
three ounces of your intensifying stock solution in your
graduate, being careful that your graduate is perfectly clean,
as the least bit of alkali or pyro would spoil the bath, and ren-
der it useless. Add to this mercury four ounces of water.
Mix this solution thoroughly before you pour it into your
tray.
138. By this time your plates have become thoroughly satu-
rated with water. Pour off the water, and pour on your inten-
sifying solution. Keep the solution flowing over the plate by
rocking the tray until the surface becomes perfectly white. Oc-
casionally examine the plate by looking through it to the light.
When the plate appears dense and the surface is quite white,
and in your judgment the plate has been intensified far
enough — taking into consideration that the plate will lose
some of its density in the clearing bath — then rinse it care-
fully in clear water for a few moments, and place the
plate in the tray containing sulphite of soda clearing solution.
Rock the tray constantly, allowing the plate to remain in the
sulphite until it has returned to its original color.
139. Re-Intensifying. — If you find after clearing that
the plate does not contain the desired strength, repeat the
operation, but before doing so wash carefully, thoroughly
eliminating the sulphite of soda so that you will carry no sul-
66 Library of Practical Photography.
pbittf into the intensifying solution. This operation of inten-
sifying can be repeated two or three times, and each time
the negative will gain in strength. After the plate is suf-
ficiently intensified and cleared, place in running water for not
less than ten minutes, or until it is thoroughly washed, and
then place in the rack to dry.
140. When to Stop Action of Intensifier. — The
greatest difficulty in intensifying plates is to know when to
stop. This can only be determined by careful observation,
watching the plate carefully, examining the surface and color of
density while the mercury is bleaching the plate, and carefully
noting how much strength it is losing in the clearing bath.
If the reader will observe, and make mental notes of the
different results obtained, he will soon be able to judge by
looking through the plate just how far to carry the intensifying.
If the plate has not been carried far enough, as stated above,
repeat the operation, paying close attention to its appear-
ance in each condition, so that you may be able to judge your
future results upon the first application.
GENERAL PRECAUTIONS TO BE OBSERVED.
141. Rocking Tray While Intensifying.— The trays
must be continually rocked while applying either solution
in intensifying to obtain even strength. The mercury trays
should never be used for any other purpose, as mercury
causes no end of trouble when coming in contact with other
chemicals. Therefore, in order to avoid this danger it is advis-
able never to use mercury trays for any other purpose than
for intensifying negatives, except for soaking the negative in
plain water previous to intensifying. If, for instance, a plate
IS developed in a tray which previously contained mercury,
even after careful rinsing, should the least trace of mercury
General Negative Intensifying. 67
remain in the tray, black streaks would be likely to appear
over the entire plate.
142. Plates Becoming Stained by Intensifying. — All
plates must be thoroughly washed and freed of hypo before
attempting to intensify. Plates which are not freed of hypo
and in this condition are intensified will become stained.
Owing to the presence of hypo in the film the clearing bath
will affect the plate unevenly, parts of it (and sometimes
all of the plate) will remain white, and not return to its
original color.
143. Strengthening Plate Without Clearing.— A plate
which is considerably under-timed, and has the least detail in
the shadows and is not hard — dense in the highlights — can
be improved somewhat by simply staining with the mercury.
Such plates soak in fresh cool water the same as usual,
and then immerse in the mercury intensifying bath until it has
gained all the color it will. Then, without clearing in the
Sulphite of Soda Solution No. 2, place the plate in clear water
and wash thoroughly, and set in the rack to dry. The plate
will be a cream color, and it is this color more than anything
else that will aid you in obtaining detail, or printing quality.
The color slows the action of the light in the printing, and
your prints will be more solid, and have more depth and
roundness. It is very essential, however, that you thoroughly
eliminate the mercury solution from the plate by carefully
washing before drying. Otherwise, the least trace of mercury
will effect your prints, especially where platinum paper is
used.
144. Avoid Printing From Plates Lacking Strength.
— Never allow a negative that is not snappy to be printed
from. It is not necessary, however, that a plate be thick and
dense in order to be snappy. On the contrary, it is just the
opposite. A good printing plate is quite thin, with clear
detail in the shadows, and the highlights crisp but not hard.
There must be half-tones in the strongest highlights. Such a
negative will yield good prints. The majority of thin nega-
tives are a trifle under-developed, making highlights a
little mushy, with lack of crispness and roundness. Such
68 Library of Practical Photograph}^.
plates should always be intensified (strengthened), and th^
highlights built up a trifle.
145. Light to be Used While Intensifying. — As white
light will not affect the plate, this work can be performed in
subdued daylight, where you can judge the proper strength
more accurately.
146. Mercury Solution Can be Used Repeatedly
Without Renewing. — The mercury, or in other words
Solution No. i, can be used repeatedly. The solution used,
however, should not be placed back in the bottle of stock
solution, but should be poured into a separate bottle, and
labeled "Intensifier ready for use." Should this bath by
constant use become weak and work slowly, add to it a little
of the fresh stock solution, thereby keeping the bath always
in good working order.
147. Clearing Solution Can be Used Repeatedly
Without Renewing. — The clearing solution, or sulphite of
soda, can be used a number of times, as long as it will clear
the plate by changing the color from white to original color.
Just as soon as the action becomes slow it is advisable to dis-
card it, and make a fresh bath.
148. Special Formula For Strengthening Negatives
of Uncertain Fixing. — Another formula which we recom-
mend in case there is any doubt in your mind as to whether
vhe negative has been properly washed and freed of hypo, is
as follows: —
Bichloride of Mercury 60 grains
Water 8 ounces
149. Add to this 150 grains potassium iodide, or enough
to nearly dissolve the red precipitate first formed. Next add
120 grains of hypo-sulphite of soda in crystals, or sixty grains
granular. In this solution immerse your plate until sufficient
density is obtained. Examine the plate by looking through
it, just as you would when using the single bichloride of mer-
cury intensifier.
150. Fixing the Plate. — After the plate has taken on as
much strength as you desire, place it in a very weak hypo-sul-
General Negative Intensifying. 69
phite of soda fixing bath, hydrometer test ten degrees, for
about fifteen seconds, after which wash thoroughly, and set up
to dry. The image on the negative will then consist of a
double iodide of silver and mercury of a reddish brown color,
with good printing qualities. This latter formula is only rec-
ommended where there is any doubt as to whether plates are
thoroughly fixed. In order to avoid using the last mentioned
bath, and to be certain that the silver is entirely removed
from the plate, it is advisable, after developing, to always fix
a plate at least fifteen minutes after the silver has disap-
peared ; then if you thoroughly wash, plates so treated can be
intensified with the first formula given, which is most simple.
151. Removing Varnish From Plates to be Intensi-
fied.— There are times when a negative has been varnished
for retouching, or for preserving the surface, which you after-
wards decide should have been intensified. To intensify such
a plate it is first necessary to remove the varnish. This you
can do by soaking the plate in wood alcohol, and then with a
tuft of absorbent cotton which has been thoroughly saturated
with the alcohol, gently rub off the varnish, after which the
negative should be placed in clear water to soak for about
twenty minutes, when it will be ready for intensifying.
152. Removing Varnish With Turpentine. — Another
method of removing varnish or retouching fluid, as well as
the lead, from a plate, is to apply turpentine with a tuft of cot-
ton. After the varnish is all removed rub the plate dry with
a little dry cotton, and then soak in clear water for twenty
minutes, after which apply the mercury.
153. Plates to Use For Experimenting. — It is advis-
able, in preparing this instruction, to make use of some dis-
carded, thin, weak negatives for your first experiments, and
intensify according to the formula given. After you become
familiar with the effect of the chemicals applied, you can then
use a plate which you desire to save and improve for future
printing, and apply the intensifier to this plate.
154. In preparing results of this instruction one should
make good proof prints before and after intensifying, and all
data pertaining to the method of intensifying the plate should
70 Librar}) of Practical Photography.
be recorded on the back of the proof, always dating each
proof and numbering whether first, second or third experi-
ment. These proofs should be filed in your proof file for fu-
ture reference, as they will be your guide in future experiments.
DIFFICULTIES IN INTENSIFYING.
155. Negatives Appearing Oily. — If the negative has not been
sufficiently washed and there is hypo present in the negative, or if it
was previously dried and then not soaked sufficiently in the water to
soften up the film thoroughly, the negative will appear greasy. Rem-
edy: If there is hypo present, intensify with the formula which contains
hypo-sulphite of soda. If the plate has been dried a long time, soak
longer in water before intensifying.
156. Judging When Plate Is Carried Far Enough in Mercury. —
If the negative needs only a slight intensification, allow it to remain in
the intensifier just long enough to whiten all over. If, after clearing, it
is not strong enough repeat the operation. In time you will be able to
judge by the appearance of the image on the surface, and by looking
through the negative. The negative, as it grows white in the intensify-
ing solution, apparently becomes a positive and, if a black rubber tray
is used, it acts as a black backing, and with very little practice you will
readily see the image gain in strength on the surface. By close ob-
servation and practice you will soon be able to judge very accurately.
157. Negative Intensifying Unevenly. — If there are spots which do
not turn white, this is a certain sign that the plate was not thoroughly
fixed, was not allowed to remain in the hypo long enough. The por-
tions not fixed will not be affected by the mercury. In such cases, in-
tensify with the formula which contains hypo-sulphite of soda, and is
intended for intensifying plates which are not thoroughly washed.
158. Negative Stained After Going Through Clearing Bath Sul-
phite of Soda Solution. — This is a certain sign that the negative was not
thoroughly washed after fixing. If the negative is stained evenly
it will do no harm ; on the contrary it will add strength to the printing
quality of the negative.
159. Negative Not Clearing in Clearing Solution. — If the sulphite
clearing bath has been properly prepared, and if good sulphite was used,
the negative will usually return to its original color. Should it fail to do
so, first test the bath and see that the sulphite of soda is full
General Negative Intensifying. 71
strength. Use a fresh clearing bath. An over-worked clearing bath
will work slowly. Often a weak solution of ammonia will act when
the sulphite has failed.
160. When to Use Ammonia Clearing Bath.— On under-timed
plates the increase in intensity is generally not very great, and as
the plate loses some of its density in the sulphite of soda clearing
bath, and as ammonia clearing does not reduce as much as sul-
phite, it is advisable to use ammonia for clearing on all plates that
are under-timed, and need strengthening. Ten to twelve drops stronger
ammonia in half-pint of water will clear the plate nicely, and may be
used in the above cases.
161. Shadows Remaining Weak After Intensifying. — If your neg-
ative is badly under-timed it is impossible to produce any detail in the
shadows by intensification. The best way is to simply bleach the nega-
tive with mercury. Do not place in the clearing bath (sulphite of
soda), but after staining all you can, wash thoroughly and set up to
dry. The stain, if not cleared up, will slow the printing and give you
all the detail it is possible to obtain from such a negative, and more
solid prints will result.
162. Negative Intensifying in Streaks. — If the plate is placed in
the intensifying solution, and allowed to remain there without agita-
ting, the intensification is apt to be streaky. Remedy i Always rock
the tray both when intensifying and clearing.
163. Small Opaque Spots Irregular in Shape and Size. — Opaque
spots are generally caused by undissolved particles of bichloride of mer-
cury coming in contact with the surface of the negative. Remedy: Al-
ways use the decanted clear solution.
164. Intensifier Will Not Work After Using a Few Times. — If
the intensifying solution refuses to work, it is because the mercury by
constant use has become weak. Remedy: Strengthen by adding a tri-
fle of fresh stock solution of bichloride of mercury, or if it still refuses
to act, then the life of the mercury has become entirely exhausted, and
you should make up a new bath.
165. Intensifying Solution Becomes Milky. — This is caused by
some of the sulphite clearing solution getting into the bichloride of
mercury solution. Remedy: Discard this solution. Make up a new
one, and be careful to never allow the sulphite solution to come in con-
tact with the mercury. If you place your fingers in the clearing bath
(sulphite of soda), wash them thoroughly before placing in the intensi-
fying solution.
166. Appearance of Old Negatives Which Have Not Been Properly
Fixed and Washed. — If the negative is very old, and it contains hypo,
there will appear a vapor-like scum on the surface. It is then best to
assume that it has not been properly fixed or washed, and if such a neg-
72 Library of Practical Photography.
ative is to be strengthened, intensify with intensifying solution
which contains hyposulphite of soda.
167. Removing Varnish. — By carefully following the instruc-
tions given in the lesson, you should have no trouble in removing
varnish. If the turpentine will not remove the varnish, try soaking
the plate in alcohol. If when the plate has been soaked in wood
alcohol, you find after rubbing with absorbent cotton that there
still remains varnish, soak longer, use fresh alcohol, then wash
for twenty minutes in running water, and you will find that all the
varnish has been removed.
ADDITIONAL INTENSIFYING FORMULAE.
Mercury Bromide Intensifier.
Bichloride of Mercury 30 grs.
Bromide of Potassium 30 grs.
Water (warm) 6 ozs.
Add one ounce of the above solution to 4 ounces of water;
in other words, enough water to cover the plate being intensified.
When thoroughly bleached in this solution the negative may
be blackened in the usual way, by placing in the sodium sulphite
bath, testing about 40 hydrometer test.
Monckhoven's Silver Intensifier.
Solution A.
Bromide of Potassium 60 grs.
Bichloride of Mercury 60 grs.
Water 6 ozs.
Solution B.
Cyanide of Potassium 60 grs.
Nitrate of Silver 60 grs.
Water 6 ozs.
The silver and cyanide are dissolved in separate lots of water
(3 ozs. of water for each), and the former added to the latter
until a permanent precipitate is produced. The mixture is allowed
to stand in the sun for 15 minutes, and after filtering forms Solu-
tion B.
Place the negative in Solution A until it becomes white;
then rinse and transfer it to Solution B to blacken. If the intensi-
fication has been carried too far, it may be reduced by treatment
with a weak solution of hyposulphite of soda.
CHAPTER VI.
LOCAL INTENSIFYING.
i68. The object of Local Intensifying is to strengthen
only parts of the plate which are weak. There are
cases where, if we strengthen only a portion of a negative
and allow the rest to remain as it is, the printing quality
of the negative will be greatly improved. There may be
portions of a negative which are a trifle soft, which,
if strengthened, will produce stronger highlights. Often
in a landscape the sky and distant objects are strong,
but the foreground, especially if there is much green
foliage, is thin and prints black. This foreground should be
strengthened by local intensification. As there is danger of
the solution spreading beyond the parts you desire to
strengthen, great care must be exercised in doing the work.
The greatest difficulty lies in applying the intensifier only
to the parts that you desire to improve, avoiding its spread-
ing to the parts that are already strong enough.
169. How to Proceed. — Place the negative which you
desire to intensify locally, in a tray of water, and allow to
soak for about ten minutes, or until the film has become thor-
oughly saturated with water. While the plate is soaking
prepare the intensifying solution : —
Intensifying Stock Solution No. i 2 ounces
Water 4 ounces
170. Place this intensifying solution into the tray that you
have set aside to be used only for intensifying, and immerse
n-5 78
/4 Library of Practical Photography.
the negative for a moment. Do not wait until the plate has
turned white. The object of this is to slightly stain the entire
plate, so that when you are applying the intensifier locally
there will be less danger of staining should it happen to
spread. Should it spread slightly beyond the parts you wish
to strengthen it will spread gradually, and do no harm.
Still had you not previously immersed the entire negative,
giving it only a slight stain, it would be very noticeable.
After immersing the entire plate for a moment, and rinsing
as already stated, set it up to drain for a few minutes. While
the plate is draining, pour about one ounce of the intensifying
solution into a small dish, or saucer, and add to this two
ounces of water. Next dip the fine point of a small camel's-
hair brush in the solution which you have poured into the
saucer, or dish, and apply to the parts that you wish to in-
tensify. Be careful to use only a little intensifier, and apply
only on the parts to be strengthened. If it spreads, immedi-
ately rinse the plate under the tap, and try it again. Always
touch the brush in the exact center of the part which you in-
tend to intensify.
171. Why a Weak Intensifying Solution is Used. —
You will note the intensifying solution for local intensifying
is much weaker than the solution used when intensifying the
entire plate. This is because with a weaker solution you
have better control of the intensification, and there is, there-
fore, less danger of over-doing or intensifying parts of the
negative which should not be strengthened. Too strong a
solution will have a tendency to spread. A weak solution is
easily controlled during the application, with little danger of
injuring other parts of the plate.
172. After you have obtained the desired strength in the
weak portion, rinse in clear water, and then re-immerse the
entire plate in this weak intensifying solution. This final
immersion is given for the same reason that you immerse the
plate before the local application. However, at this time
your plate has been materially strengthened locally, and if
any of the solution has spread beyond the parts intended, it is
apt to be noticeable unless the plate is again immersed for
Local Iniemifying. 75
a moment or two, just enough to nicely blend the local work
to the remainder of the plate.
173. Clearing the Plate. — After this immersion, rinse the
plate carefully for a minute and then immerse in the sulphite
of soda clearing bath, until the entire plate has resumed its
original color. Use the clearing bath given in instruction on
Intensifying, Part I. (See paragraph 136.) There is ab-
solutely no excuse for a flat printing negative, for if by im-
proper treatment in the developer or improper exposure the
developed plate is flat and lacks snap and contrast, one can
strengthen the highlights, lighten the shadows, supply catch
lights to drapery, lighten the hair where it is too dark and
build in detail in the dense shadows, etc. For landscape
work the improvements are still more apparent, in fact, with
proper care one can produce almost any result. You must
work cautiously, however, as great care must be exercised
when applying the mercury locally, or you may ruin the neg-
ative.
174. Caution: — Bear in mind that the plate must have
been thoroughly washed and freed of the fixing salt (hypo-
sulphite of soda) before you attempt any intensification. If,
after the negative is dry, you find it is not strong enough, re-
peat the operation, and in this case you need not place the
whole plate in the intensifier, but soak in clear water for ten
minutes ; after which apply the intensifying solution with the
brush to the parts you desire strengthened, exactly as in your
first operation. When you have the proper strength, clear
the plate in the sulphite solution, and then wash thoroughly
and dry as usual.
175. Locally Intensifying Negatives While Dry. — An-
other method which is very practical, and which one should ex-
periment with, is intensifying the negative while it is dry. To
do this place on a piece of glass a few drops of the weakened
mercury solution. To this add two or three drops of glycer-
ine, and mix thoroughly. The glycerine will prevent the so-
lution from spreading on the plate. Dip your brush in this
solution, and apply carefully to the parts to be strengthened,
always touching the center of the part first, and being careful
76 Library of Practical Photography.
not to have too much of the solution in your brush. Allow
this to remain on the parts until the desired strength has been
gained. Then rinse and place in the sulphite of soda clearing
solution, after which thoroughly wash and set up to dry.
176. Plates to Use for Experimenting. — For your ex-
periments we would advise that you use discarded plates.
After you have full control of the solution and can apply the
liquid as you want it, without spreading, take up a good
plate which you think can be improved by this treatment.
Then proceed to carefully apply the solution where it is
needed, working from the center, and blending gradually
from the stronger highlights.
177. When to Apply the Intensifier. — As in reducing,
the best time to apply the intensifier is immediately after the
plate has been thoroughly fixed and washed. The gelatine
film being swollen is most receptive and the intensifying is
quickly done. Always be sure that the plate is perfectly
washed after developing and fixing before intensifying, for
if any trace of hypo is left on the plate it will cause a stain.
The plate must also be thoroughly washed after intensifying.
178. In preparing results of this instruction, the same
methods must be pursued as with the other instruction.
Make good proof prints from each experiment, numbering
them in regular order, and noting all data pertaining to
the manipulation on the back of each proof, thus supplying
valuable data for your future guidance.
DIFFICULTIES — LOCAL INTENSIFYING.
179. Parts not Improving by Intensifying. — If the negative has
been fixed in an acid hypo bath, or the plate was placed in a hardener,
it will be almost impossible to intensify successfully. A plate of this
kind should be thoroughly soaked in water for hours, and often you will
find it necessary to strengthen the intensifying solution.
180. Intensifier Spreading. — To overcome this difficulty be very
careful when applying the intensifier. As soon as there are signs of
intensifier spreading, rinse and drain for a few minutes, and then apply
Local Intensifying. 77
again, being careful to have only a little of the intensifying solution in
the brush, and applying it exactly in the center of the part you wish to
intensify. If it again spreads rinse at once, and repeat the operation.
If this is not successful use the glycerine formula.
i8i. Judging When Sufficiently Intensified. — Only practice and
close observation can teach you this. It is always safe to stop the inten-
sifying a little before you think it is strong enough, and repeat the
operation if you find the parts have not gained enough in strength.
182. Intensified Portions Stained After Going Through Clearing
Solution. — If there is any hypo present in the plate it will always stain.
If the clearing solution is not strong enough you will obtain a stain.
If the plate originally was discolored a trifle, this stain will appear con-
siderably stronger. Be sure and use fresh clearing solution, and see
that your plates are thoroughly freed of hypo before attempting to
intensify.
183. Parts not Improved by Intensifying. — A very badly under-
exposed plate can never be locally intensified successfully, as the
shadows have nothing in them. The highlights should always take on
a certain amount of density. If any part you wish to strengthen turns
to a white or cream color, you can be sure that it is somewhat
strengthened. In some cases you will find it best not to clear the plate
after intensifying; allow it to remain this cream color, as the stain color
will slow the printing, and assist in supplying strength and detail.
184. Plate Refusing to Clear in Clearing Bath.— See Difficulty,
Intensifying, Part I, paragraphs 159-160.
185. Applying the Glycerine Intensifier to Dry Negative Without
Efifect.— This is probably due to the plate being fixed in a hardening
bath, or an acid hypo. Hold the plate flat, and apply the solution
freely, and allow it to remain on the plate for a little while. It may
take some time for the solution to take effect, and make any change.
186. Glycerine Intensifier Spreading. — To overcome this difficulty
add a drop or two more of the glycerine, and be careful not to apply
too much of the solution to the part of the plate which you intend to
intensify.
Any other difficulties met with are very likely covered in Part I. —
Intensifying.
"AT PEACE"
Study No. 4, See Page 343 Dr. A. R. Benedict, Montclair, N. J.
CHAPTER VII.
DEVELOPING OVER-EXPOSURES.
187. The exposing of plates, or film, beyond the latitude
in which they may be developed in a normally prepared de-
veloper, should be avoided wherever possible.
188. Until one becomes thoroughly trained in the required
amount of exposure to be given they will occasionally mis-
judge the necessary exposure, and in the majority of cases
such plates or film are over-timed. The object of this in-
struction is to correct these exposures in the development,
and thereby produce good printing negatives, which, if devel-
oped, in the ordinary way, would be lost.
189. Construction of Sensitive Emulsion. — Before
taking up the manipulation of over-exposed plates generally,
we will consider of what the sensitive emulsion on a dry
plate is composed, and how constructed. The emulsion of a
dry plate is a mechanical mixture of some viscous substance,
and sensitive salts of silver in extremely minute divisions.
These minute particles of silver are held in suspension by
the viscous substance, which may be either gelatine, collodion
or albumen. For the dry plate, however, it is generally gela-
tine.
190. To more clearly explain why the silver salts are dis-
tributed in minute particles, and held in suspension in the
emulsion, suppose we pour into a graduate a certain amount
of water. To this we add a small quantity of common table
salt, and then add a little nitrate of silver solution. The entire
solution will immediately assume a milky appearance, because
we have formed, when mixing these ingredients, silver chlo-
ride. This silver chloride will, in a very few minutes, fall to
81
82 Library^ of Practical Photography.
the bottom of the graduate, and the clear solution of water
may then be decanted. If, however, you substitute a warm
solution of gelatine, or some gummy substance, in place of
water, and then add the salt and nitrate of silver, you will
obtain the same milky appearance, but the minute particles
of sensitive silver salts will remain suspended. With these
ingredients for the principal basis, a sensitive emulsion is
formed which can very readily be flowed over a glass plate or
film. When this emulsion is set and dried upon the glass it
is then termed a Dry Plate, which is very sensitive to light.
191. When we place the dry plate in the plate holder, and
attach it to the camera, it is ready for exposure. The slide
being drawn, and the shutter opened, or the cap removed
from the lens, thereby exposing the plate, the light admitted
through the lens effects these minute particles of silver which
are suspended in the gelatine. A certain amount of light is
required to perform this work, and this amount of light you
measure by the length of the exposure. If more than the
necessary amount should be given, the plate will require
treatment in the development of the image, to overcome the
excess exposure given.
192. Action of Light on Dry Plate as Compared to
Printing-Out Paper. — This action of the light on the dry
plate is in some respects similar to that of sensitized printing-out
paper. If you place a piece of printing-out paper on a nega-
tive, and place it in the sun, the light affects the parts of sil-
ver in the emulsion on the paper in the same way as on the
dry plate, the only difference being that the emulsion on the
paper is of necessity made less sensitive than the dry plate,
because the emulsion used for sensitizing paper contains
materials that cause the image to become visible as it
prints. Therefore, you can see the image appear during the
exposure on the paper, while it is invisible and does not show
on the dry plate. The sensitive emulsion of a dry plate is
also many times more sensitive than that of a printing-out
paper ; therefore, while practically the same action is taking
place when the light comes in contact with either of the two,
yet its action is much slower on the paper than on the plate.
Developing Over-Exposures. 83
193. If you were to continue printing sensitized paper be-
yond a certain stage, you would have over-printed ; and the
print would be too dark, and entirely worthless. This is ex-
actly what happens to a dry plate when it is over-exposed.
The plate, like the over-printed print, has become too dark,
as it were, but unlike the print it is not lost, providing the
proper measures are taken to cut off or remove some of the
minute particulars of sensitive silver salts, which have been
acted upon by the light.
194. Restraining the Sensitive Emulsion. — To illus-
trate : The sensitive emulsion on the plate is composed of
layer upon layer of these minute sensitive silver particles. If
you exposed the plate and gave two seconds' exposure and the
correct exposure required but one second, it becomes necessary
to cut off or make a number of these layers of minute silver
particles unchangeable. Or, in other words, restrain them
from developing so that when the developer comes in contact
with them it will have no effect. This is generally done
either by immersing the plate before developing, in a bromide
of potassium solution, or, developing in old developer (devel-
oper that has previously been used), and which, of course,
contains bromide; the bromide having been liberated from
plates previously developed. For description of the action of
bromide, see paragraph 35 — Dry Plate Developing.
195. Why Plates are Over-Timed. — The best photog-
raphers are apt to misjudge the strength of the light em-
ployed, sometimes due to the variance of the light at
different times of day, or conditions of weather (cloudy
or dark days), but more especially when they are in a
hurry. While no two photographers will work alike,
although they are aiming for the same effects, each has
his one peculiar way of controlling and measuring the
light employed in producing the desired result. Yet, there is
one point upon which all agree, that is, that an over-timed
plate, or film, is preferred to an under-timed one. The reason
for this is that sufficient exposure is always required to supply
detail to the shadows, and in an over-exposure we are always
sure of the necessary detail even in the deepest shadows, while
84 Librarxf of Practical Photography.
in an under-exposure this detail is generally lost. It is much
easier to rectify the exposure so as to retain the detail in an
over-exposed plate than it is to obtain detail in a plate, or film,
which has been under-exposed. The reason is that with an
under-timed plate the exposure has been insufficient to supply
the necessary detail, and even with the most careful handling
in the developer sufficient detail cannot be produced, espe-
cially if the plate is very much under-timed. In some instances,
however, if not badly under-exposed, fair results can be ob-
tained in an under-timed plate, but the results are uncertain.
With an over-exposed plate one can always regulate the
developer so as to produce negatives with good printing quali-
ties. It is for this reason that many plates are over-timed.
196. Use of Old or Once Used Developer. — In order
that you may at all times be supplied with a restraining bath
that may be applied to plates that are over-exposed, it is advis-
able to save the last normal developer used. It is a good
practice also, after each developing in normal developer, to
pour the solution used into a wide-mouthed bottle. The reason
for using a wide-mouthed bottle is that it is much easier to
decant the clear liquid from such a bottle. It is also much
easier to pour the used developer into a large-mouthed bottle
without the use of a funnel. In order to keep the developer
free from dust, cover this bottle with a piece of glass, or cork
it. This old developer having become charged with bromide
liberated from the plates previously developed, will make a
good restraining bath. This used developer will become
somewhat discolored, but the very fact of its being discolored
makes it all the better. This discoloration will prevent the
light from the ruby lamp — even though slightly actinic —
from affecting the plate while in the developer.
197. The Use of Two Trays For Developing.— In
case of uncertain exposure, whether over or under-timed, and
even for properly timed plates, a good method to adopt is to
use two trays for developing. The reason for this is that
should you find a plate over-exposed you can immediately
transfer it to the tray which contains the old developer. Use
one tray for normal developer, starting all plates in this. In
Developing Over-Exposures. 85
the other pour the old developer previously used, decanting
clear solution. By clear solution we mean, not a solution that
is clear in color, but simply clear of particles of dirt, or film,
which might have come from the plates that were previously
developed. Having placed the plate in a normal developer,
watch it very closely and when the image begins to appear ex-
amine the plate and note the parts which should appear first.
The parts which will naturally appear first will be the high-
lights, or the whitest parts of the image. Note if the shad-
ows are holding their relative value to these highlights.
198. Developing Different Brands of Plates. — By rela-
tive value we mean the natural gradation from the highlights
to the deepest shadows, taking, of course, into consideration
that different brands of plates develop differently. For in-
stance, with Cramer plates the entire image, both highlights
and shadows, will appear, if not over-exposed, at about the
same time ; that is the highlights will be closely followed by
the shadows. However, each light and shadow will appear in
their proper tone and will grow stronger as the plate continues
developing. When developing this brand of plate with correct
exposure, you pay little attention to the shadows, so long as
they remain clear, but develop entirely for the highlights in
order to obtain their proper strength. When they are fully
developed the shadows will also be developed.
199. In case, however, of over-exposure on Cramer plates,
the shadows will flash up quickly, and be quite hazy. They
will have a foggy appearance, there will be a lack of distinc-
tion between highlights and shadows. The entire plate will
appear fogged, the amount of fog ranging according to the
over-exposure. If only slightly over-timed, the fog visible
will be only slight. If very much over-timed the fog will
not appear greater but much earlier (quicker). In either
case, place the plate immediately into the tray containing the
old developer and allow it to remain there until the fog is
checked and the plate is sufficiently restrained, always rock-
ing the tray to keep the developer moving.
200. With almost all other brands of plates the highlights
appear some little time before the shadows. Even if over-
86 Library of Practical Photography.
timed, the highlights will appear first, then the middle tones
and finally the shadows, but if over-timed the shadows will
soon begin to fog over. As soon as they show signs of fog,
indicating over-exposure, they should be restrained at once by
placing them in the old developer. When developing any
brand of plate bear this in mind, because, should the image
flash up quickly, the shadows appearing at almost the same
time as the highlights, you will know the plate is over-timed
and you should immediately transfer it to the tray which con-
tains old developer. If the plate seems quite hazy, indicating
very much over-exposure, then add to the old developer, a few
drops of ten per cent, solution of bromide of potassium, a
stock solution which should be kept on hand at all times.
201. Preparing a Ten per Cent. Solution of Bro-
mide.— To prepare this stock solution in a twelve-ounce bot-
tle dissolve one ounce of bromide potassium in ten ounces of
water, which, when dissolved, will give you practically a ten
per cent, solution. The old developer, and additional bro-
mide acting as a restrainer, checks the further development of
the shadows, and permits the developing agent (pyro), to
build the highlights to their proper density,
202. Developing Extreme Over-Exposures. — In case
the plate is very much over-timed, it may require more dense
developing than for normal exposure. This you can do by
simply allowing the plate to remain in the developer longer
than usual, even in the restraining bath. This prolonged de-
velopment may be necessary in order to produce the desired
contrast. No matter how strong a plate is developed, it is
not carried or developed far enough unless the desired con-
trast between the highlights and shadows is visible, even if
the plate does appear extremely dense.
203. When the desired contrast is reached, the plate may
be fixed in the regular hypo bath. After fixing, the plate
should show a fine contrast and a beautiful negative except
that it is very hard and dense and would not produce a good
print. Therefore before washing place this plate in your re-
ducing tray and reduce it to the proper strength. (See In-
struction on Reducing.) After reducing, rinse oflF both sides
Developing Over-Exposures. 87
in plain water, return the plate to the hypo bath for a few min-
utes and then wash thoroughly and place in the rack to dry.
In case the plate is so much over-exposed that it becomes
fogged, even in the restrained developer, then carry it as far as
possible in the developer so that the plate is quite dense
throughout. Then fix, after which reduce \ery thin — thin-
ner than you desire the finished negative. This will remove
all fog. Wash well, after which intensify to the proper
strength. (See Chapter V for Intensifying.)
204. Reducing Over-Developed Plates. — You will
notice by reference to the instruction on Reducing that we
recommend two different formulae for reducing, one of which
acts on the highlights almost entirely. This is the persul-
phate of ammonia reducer. ( See paragraph 274.) The red
prussiate bath, while it acts upon the highlights, also reduces
the shadows. (See Chapter X on Negative Reducing.)
Before reducing an over-exposed plate which has been pur-
posely over-developed, you must examine the plate thor-
oughly in order to determine which solution to use. If your
plate is strong in the highlights only, and the shadows are
clear and about the proper strength, you must use the solu-
tion that acts mostly on the highlights, which would be the
persulphate of ammonia. On the other hand, if the plate is
developed quite evenly and needs a general reducing in both
highlights and shadows, use the red prussiate of potash.
You will find a plate which has been extremely over-exposed
and over-developed should always be reduced with the red
prussiate of potash, for the reason that both the highlights
and shadows are very much too strong and an equal reduction
is required.
205. Restraining the Plate too Quickly. — Cau-
tion: When developing a plate and you find it over-timed,
do not be in too big a hurry to place it in the restraining
bath ; allow it to develop until you have secured the neces-
sary detail in these shadows. However, in a very much over-
timed plate there is danger of waiting too long. You must,
therefore, carefully watch the plate and just as soon as you
find that instead of the detail in the shadows gaining strength
88 Library of Practical Photography.
they are becoming flat — fogging over — at once place your
plate in your restrainer. On the other hand, if you have not
developed your detail before the plate has reached the re-
strainer you will have difficulty in obtaining it afterwards.
Your restrainer prevents the shadows from building up and
permits the highlights to strengthen while the shadows are
being restrained, or, in other words, the shadows have
stopped developing.
206. Plate Developed Too Far Before Restraining. —
In case the development has been carried too far in the nor-
mal developer before restraining, and you have clogged the
shadows, then it will require further development in the re-
straining bath. In other words, allow it to remain in the re-
straining bath considerable longer so as to build up the re-
quired contrast which must be obtained before the plate is
fixed. A plate of this kind may appear extremely dense, so
dense that it is almost impossible to see through it when hold-
ing it up to the light. This, however, must not alarm you
because you cannot injure the plate no matter how dense it
may be, as after fixings you reduce the entire plate to where
you want it, and you will have obtained a negative of good
printing quality.
207. Treatment of a Plate Which You Know Before
Developing to be Over-Timed. — If you are aware in ad-
vance that a plate is over-timed, then in place of starting to
develop it in normal developer start it in old developer first.
If you have no old developer on hand, add a few drops of
bromide solution to fresh developer. This will answer the
same purpose.
208. Always have on hand a ten per cent, solution of
bromide of potassium. Have it ready in case of over-expos-
ure. A few drops added to the developer will add much to
your restraining. If you have started a plate in normal de-
veloper, and you find it slightly over-timed, and needs
restraining, do not add bromide while the plate is in the
solution, but remove the plate, holding it under a tap of
running water. While adding the bromide to your bath,
rock the tray thoroughly, thus mixing the chemicals. Then
Developing Over-Exposures. 89
return the plate to the bath. This must be done rapidly, be-
cause even though your plate is removed from the bath it will
keep on developing.
209. Treatment of Plates Slightly Over-Exposed. —
In case the plate is slightly over-timed, and needs only a little
restraining, we would advise using only half old and half new
developer. The old developer will have sufficient bromide in
it to restrain the shadows while developing until the high-
lights are carried to their proper strength. Sometimes a plate
that has been only slightly over-timed may be restrained too
much, and the consequence would be that you would produce
a contrasty negative with no detail in the shadows. As soon
as a plate during development shows signs of too much con-
trast, immediately rinse in plain water, then place it in a nor-
mal developer, in which conclude the developing. This may
also be the case with very much over-timed plates, where a
too strong restrainer is used. If you find the plate building
up with too much contrast, immediately rinse the plate in
clear water, and transfer to normal bath.
210. Practice Work. — In preparing this instruction, you
make two exposures of the same subject under the same con-
ditions, over-exposing both. Develop one in normal devel-
oper, and the other treat according to instructions given in
this instruction for over-timed plates. Dry the negatives,
and make good proof prints. Carefully note on back of
prints which method of developing was employed, and any
data relating to the manipulation, such as time required for
complete development, first appearance of image indicating
over-exposure, how restrained. Each print must bear the
exposure given; this is important.
CHAPTER VIII.
DIFFICULTIES — DEVELOPING
OVER-EXPOSURES.
211. Action of Developer on Over-Exposed Plates. — A plate that
is over-exposed will flash up quickly, as soon as the developer is flowed
over it. The quicker an image appears or flashes up the more it is
over-exposed. The image on a plate or film, normally exposed, should
appear in not less than one-half minute, much depending upon the
strength and temperature of the developing solution. Warm developer
will develop more quickly than cold. Strong developer will also de-
velop more rapidly than normal or weak developer. The entire outline
of the image on a normally exposed plate will generally appear in from
thirty to fifty seconds, and the image on the plate will gradually con-
tinue to grow, until the entire image is developed. The image flashing
up in from five to eight seconds is over-exposed and must be restrained
immediately, and the amount of restrainer must be judged by the ra-
pidity of the appearance of the image. The quicker the image appears
the stronger must be the restrainer. The following suggestions may be
of service to those whose practical experience in the handling of over-
exposures has been limited. These suggestions are based on the pre-
sumption that only pure chemicals are used in preparing the developer,
and that they are mixed according to the formula and, of course, the
plate must be started developing in normal developer.
212. First. — If the image appears in thirty to forty seconds, the
exposure is normal and should be developed to completion in the nor-
mal developer.
213. Second. — If the entire image appears in eighteen to twenty
seconds, the plate or film has been over-timed beyond the latitude for
development in a normal bath, and the plate should be restrained at
once, either by adding one-half old bath to the normal developer, or by
transferring the plate to a tray containing old or once used developer,
allowing it to remain in this bath for two minutes. If then it shows too
much contrast, rinse it in clear water. Then return the plate to the
tray of normal developer and conclude the development in this tray.
n-6 91
92 Library of Practical Photograph}).
Should the plate or film after being two minutes in the old developer,
appear flat and without contrast, then complete the development in the
tray of old developer.
214. Third. — If the image appears in fifteen seconds, the plate or
film is considerably over-timed, and about ten drops of a ten per cent,
solution of bromide should be added to the old developer, and the plate
transferred at once from the normal bath to the restraining bath. The
tray must be agitated continually and the plate examined occasionally,
and if the bath is not too much restrained, the development may be
concluded in this bath.
215. Fourth. — Should the plate flash up in eight to ten seconds, the
plate is very much over-timed, and should be placed in a bromide re-
straining bath, made up as follows : To three ounces of water add one
and a half drams of ten per cent, solution of bromide. Immerse the
plate in this bath for one minute. Then transfer to a tray containing
old developer, and conclude the development in this bath. Should the
plate, or film, show signs of over- restraining and develop too contrasty,
then return the plate to the normal developer.
216. Fifth. — If the plate flashes up in from three to five seconds, or
almost immediately after developer is flowed over it, the plate is greatly
over-timed and should at once be placed in a tray of old developer and
allowed to remain there while preparing a bromide bath of two ounces
of a ten per cent, solution of bromide and four ounces of water. Trans-
fer the plate immediately to this bath, allowing it to remain for two
minutes. Then return to the tray of old developer for final develop-
ment, and if necessary in order to obtain strength, finally finish the de-
velopment in the normal bath.
217. Developing Plates of Doubtful Exposure. — There are times
when one is obliged to make an exposure under circumstances which
make it difficult to judge the exact exposure required. Under such
conditions it is always advisable to make two exposures, one of which
should be according to your judgment of the proper exposure ; the other
give a longer exposure, or, in other words, over-time it. Mark both
slides, and make a memorandum of the exposure given, and when you
come to developing, develop first the plate which in your judgment was
the normal or proper exposure, starting it in normal developer. If it
proves over-timed transfer it at once to the tray containing old devel-
oper. If it develops slowly, indicating under-exposure, add more water
to the normal developer. The developing of this first plate gives you a
key to the second plate. If the former was over-timed then you would
start the second plate in old developer, and if the first was considerably
over-timed, then you will need to restrain the second one considerably.
You should then add to the old developer two drams of the ten per
cent, solution of bromide. On the other hand, should the first plate
prove under-timed slightly, the second plate should be developed in
Difficulties — Developing Over-Exposures. 93
normal developer. Under all circumstances, your first plate supplies
you a key for the treatment of the second one.
218. Judging During Development How Much the Plate Is Over-
Exposed. — It often occurs that the photographer, during the course of
a day's work, makes a number of exposures, and, in his judgment, cor-
rectly times all of them. However, when he comes to developing his
first plate he finds that he has erred in his judgment, and the plate is
over-exposed, realizing that all plates exposed that day are over-timed.
It is a question now as to how badly each plate is over-exposed and how
to treat the remainder of the plates so as to produce good results. All
will depend upon the first plate developed. This first plate is your key
and will indicate how much over-exposed the remainder of the plates are.
219. If they are only slightly over-timed, it is advisable to develop
them in the old normal developer from the start. You must bear in
mind that this old, or once used normal developer, must not contain any
other restraining properties. In other words, this developer has been
used as prepared according to the formula and has not been altered in
any way. If, for instance, bromide had been added to the normal de-
veloper, this would cause the old developer, when used on only slightly
over-exposed plates, to develop too contrasty. Therefore, use old de-
veloper which was prepared normally and has developed one lot of plates
only. Such a developer usually will restrain the plate sufficiently and
good crisp negatives will result. However, if the first plate developed
appears quite hazy, it may be well to add a few drops of a ten per cent,
solution of bromide to the used normal developer. It is well, under
such circumstances, to develop each plate separately until you arrive at
a developer that is sufficiently restrained to produce good, crisp nega-
tives from the start ; then the remainder of the plates should be devel-
oped in a developer made accordingly.
220. After a little practice one will be able to judge by the appear-
ance of the first plate developed exactly how much the others are over-
timed, and will know exactly how much restraining is required.
221. Obtaining Desired Contrast of Over- Timed Plates. — When a
plate is only slightly over-exposed, treat it according to paragraph 32,
Instruction, Dry Plate Developing. If, however, it is badly over-
exposed and you are developing according to instructions, and you can-
not produce the desired contrast, it is because you did not allow the
plate to remain in the restraining solution long enough before transfer-
ring to the normal developer. Or, if the plate was started in the normal
developer, you may have allowed it to remain too long in this developer
before checking or restraining. In either case if the plate shows flat-
ness throughout the development, you must then over-develop to an
extreme, and after fixing the over-developed plate then reduce it accord-
ing to Instructions on Reducing Over-Developed Plates.
222. Obtaining Clear Shadows. — You can only retain clear shad-
ows in developing, should the plate be over-exposed, by the proper
94 Librar}) of Practical Photograph}).
amount of restraining, either by the use of sufficient bromide, allowing
the plate to remain in the bromide solution sufficiently long to properly
restrain the shadows from developing before transferring the plate to
the normal developer ; or, by the use of old developer and the plate re-
maining in this old developer sufficiently long before transferring to the
normal developer. The amount of restraining all depending on the
amount the plate is over-timed. Bear in mind at all times that a plate
that has been started in normal developer which proves to be over-timed
will be fogged, and sort of a veil will appear over the shadows if the
plate is allowed to remain too long in normal developer before restrain-
ing, no matter what restraining methods you use.
223. It is, therefore, evident that the first few moments the plate is
in the developer are the most critical ones. It is during these moments
that you must watch the progress of the plate, and the instant it shows
signs of over-exposure the proper restraining must be done at once in
order to retain clear shadows.
224. Again, you cannot expect to obtain clear shadows if your de-
veloping light (ruby light) is too strong. A light which would be
perfectly safe, for correct exposures, may not be safe for over-exposures.
The developing of an over-timed plate is slower than that of a properly
exposed plate; consequently, the over-timed plate is exposed to the
ruby light longer tnan a normally exposed plate, and, therefore, is sub-
ject to more or less fog from this light. It is well, under such condi-
tions, to do your developing farther away from the ruby light so that
only weak light falls upon the tray containing the plate and developer.
225. Sometimes high temperature in the developer or developing
room, will cause foggy shadows. Constant placing of the warm fingers
in the developer will warm the developer, and the solution exposed to
the air for a long time is apt to become the same temperature as the
dark room, and will, therefore, cause fog.
226. It is advisable when your plate is placed in a tray of restrain-
ing developer to place a cover over the tray, but do not neglect to rock
the tray, because this is necessary to insure even development.
227. How Far to Carry Development of Plates that Are Over-
Exposed. — The development of an over-exposed plate depends entirely
on how badly a plate is over-timed, and how early the plate has been
restrained in the development. It is far better to over-develop a plate,
and after fixing, reduce it, than to under-develop. By over-developing
an over-timed plate, you are aiming to build up your highlights. You
realize that your shadows have sufficient strength, but the strength of
the highlights are not sufficiently in advance of the shadows. There-
fore, you carry the development farther to build up the highlights,
knowing that the restrainer used in the development will, to a certain
extent, hold back the shadows while the highlights are growing in
stcength. In other words, by over-developing you produce stronger
highlights, and then by finally reducing with red prussiate of potash
Difficulties — Developing Over-Exposures. 95
(See Chapter X on Reducing), you reduce the shadows equally, if
anything, slightly more than the highlights and the result is a negative
of proper contrast.
228. On the other hand, if you under-develop, you produce thin
negatives with apparently plenty of detail but no contrast and no solid-
ity, and absolutely no printing quality. Therefore, it is advisable until
one becomes familiar with the proper developing of plates, under all
conditions, to over rather than under-develop.
229. Desired Amount of Bromide to Use. — Bromide is used as a
restrainer. The amount to use depends entirely upon how much the
plate is over-exposed. By using a ten per cent, solution of bromide, the
strength is such that a little more or less will do no harm ; therefore,
one can use bromide quite freely without any perceptible damage to
the plates. After one becomes accustomed to restraining with bromide
and after some experimenting with a few plates by first using, say, five
or six drops, then if this is insufficient to restrain the plates properly, the
next time try ten to fifteen drops. In this way one may soon be able to
determine the necessary amount to use. The worker, therefore, should
carefully note how much bromide he is using each time, and if the re-
sults prove that enough was used, or too much was used, govern him-
self accordingly the next time he develops an over-exposed plate.
230. How Long a Plate Should Remain in the Bromide. — Where
plates are very much over-exposed, it is advisable to place them, previ-
ous to developing, in a bromide restraining bath, the strength of which
depends upon how much in your judgment the plate is over-timed.
231. A fair rule to follow would be: If you consider a plate over-
timed three times the normal exposure, then a bromide bath of, say,
three ounces of water with one-half ounce of a ten per cent, solution of
bromide added thereto, allowing the plate to remain in this bath for one
minute, should be sufficient restraining. The plate should then be
transferred immediately to a normal developer with one or two drops of
bromide added thereto. The more the plate is over-timed the longer it
should remain in the solution. If extremely over-timed then a stronger
bromide solution should be used. Practice alone will teach you the
exact amount of bromide to use, and the length of time the plate should
remain in the restraining bath. Bear in mind that the immersing of
the plate in a bromide solution previous to development is advisable
only in cases of extreme over-exposure. Ordinary over-exposure can
be restrained by developing in old developer, or by the addition of a
few drops of bromide added to a normal developer.
232. Yellow Negatives. — Yellow negatives are generally caused
from long development due to under or over-exposure. The devel-
oping of an under-exposed plate is always slow owing to the fact that
a weak developer has been used, the emulsion on the plate is apt to be-
come soft and this gives the pyro an opportunity to stain. The devel-
oping solution by the long development becomes discolored, therefore.
% Library^ of Practical Photography.
acts as a stain upon the film. This yellow stain, however, can be elim-
inated by immersing the plate or film in an alum solution. ( See para-
graph 270, Chapter X, Negative Reducing, Part I.)
233. Using Old Developer. — When using old developer be sure and
decant and filter the solution free of dirt or particles of film before use.
The normal developer used for one developing should be your old de-
veloper for the next developing.
234. Preserving Old Developer. — For the preserving of old devel-
oper see paragraph 30, Chapter II, Dry Plate Developing.
235. Determining When to Check Development of a Plate Started
in Normal Developer — A plate should be transferred to the restraining
bath — or in other words, the tray containing old developer — just as
soon as you see the slightest signs of the shadows growing weak, fog-
ging or veiling over. As stated before, the first few moments a plate is
in the developer, it should be watched more carefully than at any other
time. If you are developing several plates at a time, and one or more
of them show signs of fogging in the shadows, transfer them at once to
the old developer. Watch your plates closely and act quickly. Do
not hesitate to transfer the plate to the tray of old developer if it shows
the least sign of fog or flatness, for even should you be mistaken you
cannot injure the plate by so doing.
236. Clearing Stained Negatives. — To remove the stain from neg-
atives. ( See Chapter X, Negative Reducing.)
237. Uneven Development. — Uneven development — or plates with
streaks in them — is generally caused by insufficient developing solu-
tion. It is also caused by not rocking the tray constantly during the
development, or by allowing the plate to remain in the bromide solution,
or in any restraining solution without agitating. A plate should never
remain in any solution, no matter what it is, without being agitated and
the solution kept constantly in motion. Too harsh rocking will give
harsh, grainy effects. Rock gently sufficient to keep any sediment from
settling on the plate.
238. Mottled Negatives. — This you can overcome by carefully
rocking the tray during development. Sometimes this mottled appear-
ance is visible on plates that have been reduced. This is caused by too
strong a reducing solution, and not rocking the tray while the plate is
reducing. Avoid too strong solutions of any kind.
239. Large Transparent Spots. — These spots are generally caused
by adding bromide to the developer while the plates are in the tray. A
drop of bromide falling upon a plate while developing, will restrain that
portion of the plate which the bromide has penetrated, consequently, a
round transparent spot will result. Streaks and spots will be the result
if the plate were allowed to lie in the bromide solution without rocking
the tray.
Caution. — Always rock or agitate all solutions while using them.
Never allow a plate or film to remain in any solution without agitating.
CHAPTER IX.
ADVANCED DEVELOPMENT OF OVER-TIMED
PLATES.
240. Most photographers have learned from experience that
it is very essential to have sufficient time on all exposures.
There are cases when in doubt as to the exact exposure neces-
sary, and in order to be positive of the sufficient time, they
expose a trifle longer than in their judgment they consider
necessary, thus over-timing the plate.
241. Such a plate, if developed in normal developer to a
finish, would be very dense, but flat. The prints from such
plates would be anything but pleasing. With the proper
manipulation, however, such plates can be made to yield very
good prints. In fact, you can manipulate so as to overcome
any reasonable amount of over-exposure, and thus save the
negative.
243. Extreme over-exposure is not encouraged by any
means; in fact, one should aim at the correct exposure at all
times, for you cannot always produce as fine a quality plate
by over-exposure as you can by correct exposure, no matter
how much you doctor the plate. There are times, however,
when plates are over-timed accidently, and these plates must
be saved, and the very best possible results secured. To
teach you how to do this is the purpose of this Instruction.
243. Over-exposing is more apt to occur in commercial
photography than in portrait work. For instance, when
making interiors, photographing machinery, furniture, stoves,
draperies, etc., such work is usually photographed at the fac-
tory, and a large number of plates are exposed before return-
99
100 Library of Practical Photography.
ing to the dark room to develop. As negatives made of
all such objects must be fully timed you are apt to overtime.
All negatives made under the same conditions are given
practically the same exposure, therefore, if one plate is over-
exposed all are. By developing one plate first you have a
key to the rest, and can treat them accordingly.
244. Any reasonable amount of over-exposing can be over-
come in the developing, provided you are aware that the
plate is over-timed, and know pretty nearly how much,
for then you can reduce the sensitometer back to that of a
slower plate.
245. Note illustrations, Nos. 7 and 8. In No. 7 we
have a plate with a two-second exposure, fully timed. No. 8
was given thirty seconds, or fourteen times more exposure than
was necessary. In order to determine exactly how much the
plate was over-timed, and to know how much the plate
must be restrained, we developed plate No. 7 first. Find-
ing this plate fully timed, we prepared to reduce the
sensitometer of plate No. 8 before developing it, by placing
in a bromide solution composed of : Water eight ounces, and
ten per cent, bromide solution, two drams. We immersed
the plate in this bath for four minutes, after which it was
transferred to a normal developer with a few drops of bro-
mide added. The results were as you see them in plate No. 8.
246. In all cases of extreme over-exposure, if you are
aware that the plates are over-exposed, apply the above
method. The longer the exposure, the more you must re-
strain the plate by immersing in a strong bromide bath.
247. When developing plates of unknown exposure, be-
lieving them to be over-exposed, always start either in old de-
veloper, or part old and part fresh. Or, if you have no
old developer on hand, use normal developer with a few
drops ten per cent, solution of bromide added. Place the
plate in your normal developer, having a second tray contain-
ing a bromide bath made up as follows : To one-half-pint of
water add two drams of a ten per cent, solution of bromide
of potassium. As soon as the image appears on the plate, ex-
amine it, and if you find it flashing up quite quickly, as soon
Illustration No. 7
A Correct Exposure
See Paragraph No. 245
Illustration No. 8
Over-Exposure Corrected by
Proper Development
See Paragraph No. 245
Over-Timed Plates. 103
as the shadows are developed, immediately place the plate in
your second tray, containing bromide bath, and allow it to
remain there for about four minutes, covering the tray to pro-
tect it from the light. The bromide at once acts upon the
shadows, and restrains them from developing farther. After
a few minutes, transfer the plate from the bromide solution to
the normal developer.
248. You may find it necessary to make up a fresh normal
developer to complete the developing. The strength of the
bromide checking bath must be determined by the appearance
of the plate when the image first appears. If the plate is
only slightly over-timed, then dilute the bromide bath by
adding double the amount of water.
249. Care must be taken when immersing the plate in
bromide bath to be sure that the shadows are fully developed,
for should you restrain the plate before all detail is developed,
then your shadows will lack strength.
250. In cases of very slight over-exposure, we advise
carrying the plate a little farther than usual in the normal
developer, and then reduce the plate after fixing, with red
prussiate of potash. (See Chapter X, Reducing.) This so-
lution will clear up the plate very nicely.
251. Caution: — If you had restrained the plate before se-
curing full detail in shadows, when concluding the developing
in normal developer, you would have found the shadows were
developing very little, owing to the fact that the film was satu-
rated with bromide. In order to secure further detail in
the shadows you would have to soak the plate in plain water
to eliminate bromide, and make a new developer weak in pyro,
containing no bromide. That would give the detail-produc-
ing chemical (carbonate of soda) a better opportunity to pene-
trate the film, and open the pores. This method will require
the developing of the entire plate farther than ordinarily.
Finally reduce the whole plate to the proper density with red
prussiate.
252. A few points must be remembered when developing
plates that are over-timed. First, — it is the shadows that
are over-timed and, therefore, they must be treated, and
104 Library of Practical Photography.
not the highlights. Second, — you must judge as near as
possible by the first appearance of the image on the plate how
much it is over-timed, and then restrain the shadows accord-
ingly. Sometimes to simply immerse the plate in a weak
bromide solution for only an instant will sufficiently restrain
the shadows to supply the desired results.
253. Should the highlights alone appear too strong after
the plate is developed and fixed, apply the persulphate of am-
monia reducer (See paragraph 274, Instruction Reducing),
as it acts on the highlights only. Immerse the plate in this
bath, and when the desired reduction is obtained place the
plate in the sulphite of soda bath, and finally wash and dry.
254. Should you know in advance that the plate is very
much over-timed, then reduce the sensitometer by immers-
ing the plate in a bromide solution before it is developed.
255. Portrait Work, Over-Exposed. — In slight over-
exposure of portraits, start the plate in half old and half fresh
developer. This many times will sufficiently restrain the
shadows. If this is not enough, you can immerse quickly the
plate for only a second in a weak bromide solution of one
dram ten per cent, solution of bromide to one-half-pint water.
The longer you allow the plate to remain in the bromide bath,
the more it will restrain. If the plate is over-exposed only a
little more than you can control with the half old and half
new developer, immerse the plate for a second in the bromide
bath. If the plate is considerably over-timed, then allow it to
remain longer in the bromide. You must be guided entirely by
the appearance of the plate when in the first developer, as to
how much to restrain it. You can restrain as little or as
much as you require by this method.
256. In order to become familiar with the advantages of
these methods of developing, make two over-timed exposures.
Develop one plate in the normal developer; the other develop
according to instructions for over-exposures. Make proofs
from both plates, noting on backs of same developer used, and
any other data that will aid you in your future developing.
Save these proofs, filing in your proof file for future reference.
CHAPTER X.
GENERAL NEGATIVE REDUCING.
Note.— In the following lesson wherever the word • ' plate " is used
" film " may be substituted.
257. There are times when, because of faulty exposure,
one finds it necessary to over-develop the plate, thereby pro-
ducing, in case of over-exposure, a negative which is too
dense. While by the over-developing the required values of
the highlights and shadows have been retained, yet the plate
will be so dense that the printing from it would be very slow and
unsatisfactory. In the case of under-exposure, the shadows
having been insufficiently timed to supply detail, the develop-
ment is prolonged in order to obtain all the detail possible in
the shadows ; consequently the highlights are over-developed,
and are too dense. The result is too much contrast, the nega-
tive having only highlights and shadows, but no half-tones,
and no gradation from the highlights to the shadows. Nec-
essarily, negatives of either the above classes are slow printers.
258. In order to improve the printing quality of such
plates, it is necessary to reduce them. Many negatives that
would be considered worthless, and are often discarded, may
be remodeled and doctored up to produce excellent prints.
In fact, in many cases the very finest prints are produced from
negatives that have been doctored ; not only reduced, but in-
tensified, in order to produce the proper gradation from the
highlights to the shadows.
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106 Library of Practical Photograph}).
259. Reducing Over-Developed Plates. — As all nega-
tives that have been over-developed should be reduced in or-
der to produce the best printing quality, we will, therefore,
consider the action of the reducing agent, of which there are
a number of different kinds, although the action of all are
practically the same. If a plate was placed under a micro-
scope of high power so that the action of the reducer on the
silver granules could be observed, you would find that the re-
ducer was dissolving, or removing these small silver gran-
ules of which the image on the plate is composed. The longer
the solution remained upon the plate the more it would re-
duce, and if the reducing agents were allowed to remain on
the negative long enough the entire image would disappear.
As this reduction, however, can be checked at any time by
immersing or washing the plate in water, one has but to
judge when the plate is reduced sufficiently.
260. Red Prussiate of Potash Reducer. — There are
quite a number of formulae for reducing. There are also pre-
pared preparations on the market. We will, however, con-
sider the two which are most generally used, and which we
recommend. The first is ferricyanide (red prussiate of pot-
ash). The reducer acts evenly on the entire plate, and
therefore the thinner portions (the shadows), are liable to
disappear before there is much change on the dense parts
(the highlights). For this reason we recommend red prussi-
ate reducer for over-exposed and over-developed plates, which
are not only slow printers, but lack in contrast.
261. Persulphate Ammonia Reducer. — The second re-
ducer which is very successfully used is the persulphate of am-
monia. This reducing agent will first attack the denser por-
tions of the negative, as they are more susceptible to the ac-
tion of the reducer. The thinner portions of the negative
(the shadows), are only slightly affected, therefore, for a
plate which is under-exposed ; or a contrasty lighting ; or an
over-developed, under-timed plate ; we recommend the use of
persulphate of ammonia. It will act upon these strong high-
lights first, and when the highlights are reduced to their
General Negative Reducing. 107
proper stage there will be proper gradation from the highlight
to the shadows.
262. Action of Reducers. — The persulphate of ammonia
not only reduces the size of the silver granules, but also alters
the character of the deposit. The granules become opales-
cent, reflecting a milky or pearly light, resulting in the re-
quired soft tones in the negative. With the red prussiate
(ferricyanide), however, the silver granules after becoming
reduced remain opaque. The action of the red prussiate is
also much quicker than that of the persulphate.
263. Use Discarded Plates, or Films, for Experi-
menting^.— As the successful performance of this work de-
pends on the proper mixing of the chemicals in the required
proportions, we advise for the first experiments the use of old
discarded negatives. When able to produce the desired re-
sults on these discarded plates, make use of these same rules
and formulae in your regular work, and apply one of the
above reducers whenever you feel that you can improve the
negative, or negatives. The expert has these reducing
chemicals always ready at hand in the dark room, and
when his practiced eye sees the occasion for their use,
on account of under or over-timed exposures, he im-
mediately applies them and, by correcting their faults, obtains
good negatives.
264. The Best Time to Reduce Plates or Film. —
The best time to doctor negatives that are to be reduced with
red prussiate, is immediately after fixing, while the nega-
tive is wet and most receptive. In case you are to reduce
plates that have already been dried, or for the benefit of
practice you are to reduce old or discarded plates, it will
be necessary for you to place the plate first in the regular
hypo bath for at least thirty minutes, so as to give the gela-
tine an opportunity to become thoroughly saturated with
the hypo. If the plate is not thoroughly saturated with
the hypo before the red prussiate touches it, it will pro-
duce stain, and the reducing will also be slow and uneven.
When reducing with persulphate of ammonia, however, it
is different. The reducing with this chemical is best done
108 Library^ of Practical Photography^.
when the plate is dry. It will act more quickly, and the
reducer will attack the highlights more readily.
Reducing Stock Solution, No. i.
265. Formula for Reducing with Red Prussiate.—
Red Prussiate of Potash (Ferricyanide) 2 ounces
Water 4 ounces
You will find a little difficulty in dissolving all the crys-
tals, but by constant shaking most of them will dissolve.
This Stock Solution must be kept in a well-stoppered bottle.
A glass stoppered bottle is recommended. Wrap the bottle
with black or yellow paper, and keep in a dark place, as
strong daylight will affect this solution, and cause it to rap-
idly deteriorate. It is necessary that you observe the caution
in regard to bottles for preserving your solution, and the man-
ner in which it should be preserved. By doing this you will
always be able to produce the best of results.
266. For use prepare as follows: To one ounce saturated
solution hypo, add one-half-pint of water (eight ounces). Add
to this about one dram of Stock Solution No. i. To make a
saturated solution of hypo, dissolve in a certain amount of
water all of this chemical that the water can hold. When
the chemical is dissolved in the water, the first portion added
may disappear quickly enough, but as more is added, the dis-
solving proceeds more and more slowly until finally it ceases
altogether, and some of the chemical failing to dissolve will
sink to the bottom and remain there. The solution is then
what is called saturated.
267. If upon applying the reducer to a plate you find that
it does not reduce rapidly enough, add a little more of No. i,
and a proportionate amount of hypo, remembering that too
little hypo will cause yellow negatives. Always bear in
mind that the hypo is your color controlling chemical, and
prevents the red prussiate from staining.
268. Reducing the Plate. — We will now suppose that
you have your reducing solution prepared, and that you have
General Negative Reducing. 109
sufficient quantity. Never try to reduce with a small amount
of solution, as the results will probably be uneven. Eight
ounces of solution in a 5 x 7 tray is sufficient for 34x5 or a
5x7 negative. Place your plate, or film, face up into the
tray which contains the solution. Rock the tray gently, but
never in one direction, as the negative will start reducing
very quickly. Examine it frequently, and always rinse under
the tap, or in clean water before examining. If you "fail to
rinse the plate it will keep on reducing while you are ex-
amining, and often times plates in this way are reduced too
far. When it is finally reduced to the desired stage, where
you have sufficient softness to the highlights, rinse it off
under the tap for a few moments, and then place it back into
the hypo for at least ten minutes. By placing back into the
hypo the color of the plate is preserved.
269. Plate Appearing Yellow. — If the plate after re-
ducing appears yellow, or at least a deeper color than you de-
sire, you have not had sufficient hypo in the reducing bath.
Sometimes the plate is yellow before reducing. In such cases
you should not expect to change the color in this bath, as the
reducing bath is not intended for clearing; in fact, it is more
liable to increase the color. However, you may reduce the
plate exactly the same as if you had the desired color, allow-
ing for the changing of color. Then after fixing properly,
and thoroughly washing the plate to eliminate all hypo, place
it in the following clearing bath : —
270. Clearing the Plate or Film. — Dissolve four ounces
of pulverized alum in one pint of water (sixteen oz. ) Place this
in a bottle, and label " Alum Stock Solution." Of this solu-
tion pour one-half-ounce into a tray, and add ten ozs. of water,
and three drops of sulphuric acid C. P. Place your plate in
the tray, and rock it freely. The color should disappear in a
few minutes. If the bath works slowly, strengthen by add-
ing more alum. When you secure the proper color remove
the plate, and wash in plain running water for fifteen minutes,
then place in the rack to dry. If you have no running water
change the water on your plate about fifteen times. The sul-
phuric acid, even when combined with the alum, acts as a re-
110 Library of Practical Photography.
ducer if used in excess quantities. Therefore, if not used
cautiously it will reduce the strength of the plate, as well as
clear it. If too strong an alum bath is used it will cause the
film to pucker.
271. Reducing Plates After They Are Dry. — Cau-
tion:— Never try to reduce a plate until it is thoroughly
fixed ; to do so will produce a green color, and the plate is
liable to reduce in spots. When reducing a plate that has
been dried, it is a good plan to place it first in cool fresh water
for a few minutes ; then transfer the plate to the regular hypo
bath, and allow it to remain about thirty minutes. Finally,
without rinsing, place the plate in the reducing bath, rocking
the tray gently. Never allow the solution to settle on the
plate for a moment, or it will be streaked.
272. Life of Reducing Solution, and How to Keep
It. — Note. — Red Prussiate of Potash, when mixed with
hypo, decomposes very rapidly, and sometimes becomes worth-
less after immersing a half dozen plates. If more than this
number are to be reduced, a new bath should be made up.
The reducing should be done in the dark room by good, arti-
ficial light. A strong daylight is not advisable, as it affects
the solution, and naturally shortens the life of the reducing
chemicals.
273. Judging Plates to be Reduced. — By exercising
judgment when to apply and use the reducer, you should
never have a dense or slow printing negative. Frequently
the true value of a negative is lost by slight over-develop-
ment, and by training the eye to see this, and reducing the
negative, it would be restored. This training is accomplished
by close observation only, and by making mental notes. Try
to impress on your memory the appearance of the plate before
and after reducing, and in a very short time you will be able
to judge just how far a plate should be reduced. You would
then be able to judge correctly as to the printing quality, and
development. If in doubt as to whether a plate would be im-
proved by further reducing, allow it to dry, and make a proof
print from it. If this proof prints slowly, and with too much
harshness and contrast, again immerse the plate in the re-
General Negative Reducing. 1 ! 1
ducer, and carry it to the proper stage. A plate that has
once been reduced, and dried, will not reduce so rapidly
the second time, even in a fresh reducing bath, and unless
the solution is agitated carefully one may find the reducer
to act in streaks. Therefore, avoid too strong a reducing for
second immersion, and don't be annoyed if the reduction
acts slowly, as the plate will be better for it.
PERSULPHATE OF AMMONIA REDUCER.
274. Reducing with Persulphate of Ammonia. — The
persulphate of ammonia does not keep well when made in
solution, and, therefore, it should be made up in small quan-
tities, mixed for immediate use. This chemical, which is a
most valuable addition to the stock of photographic materials,
is less known and made use of less at the present time than its
virtue would warrant. This is probably due, in part, to the
want of knowledge of its properties, and the conflicting re-
sults that have been obtained with the first experiments.
This, too, explains the reason for the various recommenda-
tions as to the strength the persulphate should be used at,
which has varied in many instances from one to ten per cent.
With a uniform preparation, however, the variations of re-
sults will be little or none, even when taking into consider-
ation the different requirements of the amateur and profes-
sional. The amateur with fewer negatives to attend to,
thinks nothing of spending a half-hour on a negative that he
values, but on the other hand, the professional, whose time is
money, would scarcely like to spend more than five or ten
minutes on any plate. If longer time were required he might
be tempted to leave the negative for a few minutes to attend
to some other work, and probably forget it, and the nega-
II— 7
112 Library of Practical Photograph}^.
tive in consequence would be spoiled by reducing too far. As
there is nothing gained by the use of a very weak reducing
agent, we recommend a method that will, on an average,
require ten minutes to complete the necessary doctoring.
275. Persulphate Reducer Grows Stronger with
Age. — The persulphate of ammonia from the moment that it
is made into solution decomposes, and gradually becomes
more and more acid. A good commercial sample of persul-
phate has a slightly acid action to start with, and this acid
action rapidly increases when the persulphate is made into
solution. A freshly made ten-per-cent. solution from C. P.
persulphate has but a slight acid action, and can safely be
used. This same solution, however, at the end of a week has
a very strong acid action. A one-per-cent. solution at the
lapse of a week acts more quickly than a fresh ten-per-cent.
solution. Hence, our reason for using a fresh ten-per-cent.
solution, and for making up only sufficient quantity for the
plate, or number of plates, to be reduced. If the solution is
made up of ordinary tap water, which usually contains
chloride of carbonate, the action of the chemicals is quickly
seen by the gathering of a milkiness on the surface of a nega-
tive. This is not the case if distilled water were used. It is,
therefore, advisable to use ordinary tap water, as it acts
as a guide. If old solution is used the reduced negative
will assume a sickly sepia tint, and while the strong parts ap-
parently are reduced, yet the color of the plate is such that
the negative has not been improved for printing quality by
the reduction.
276. From the above one will readily see that the persul-
phate is of uncertain action unless used fresh, and it is for this
reason that we wish to impress on the worker's mind the ne-
cessity of using a fresh solution for each lot of plates to be re-
duced.
277. Persulphate Formula. — Formula for Persulphate
of Ammonia Reducer :
Persulphate of Ammonia Crystals 50 grains.
Water 5 ounces.
General Negative Reducing. 1 1 3
If a larger bulk of solution is required, add ten grains persulphate
of ammonia for every ounce of water.
REDUCING.
278. If a 5 X 7 plate is to be reduced, five ounces solution will
be sufficient. If a number of plates are to be reduced, it is ad-
visable to make up ten ounces of solution. This bath should
be discarded as soon as you are through reducing, and if more
plates are to be reduced later, a fresh bath should be prepared.
279. We will now suppose that you have placed your re-
ducing solution in your tray. Take your negative without
previously wetting, and place it in the solution. As we have
said before, reducing with persulphate of ammonia is best ac-
complished when the plate is dry. The reducer will act with
greater rapidity, and will attack the highlights more freely.
Rock the tray gently. Examine the plate frequently, and
when it is reduced to where you want it, you can stop the ac-
tion of the reducer by first rinsing the plate in clear water,
and then immersing it for about five minutes in a sulphite of
soda solution, hydrometer test ten degrees. Or, dissolve one
ounce of sulphite of soda in ten ounces of water. After soak-
ing in this bath for a few minutes, wash in plain running
water, and then place it in the rack to dry.
280. Reducing Plates Hardened in Alum. — The Per-
sulphate Reducer will not act well upon plates that have been
soaked, and hardened in alum. If you have plates which have
been so treated, place them in plain water for ten minutes be-
fore applying the reducer. The soaking of the plates will
soften the film, and open the pores, which have been closed
by the action of the alum, the reducer will then act more freely.
281. Traces of Hypo in Persulphate Bath. — When
using this reducer the negative must be freed from every trace
of hypo. You are, therefore, cautioned upon the importance
of using separate trays for different chemicals. If you have
but one tray to use for reducing, you must see that it is thor-
oughly cleansed before using. For instance, should you have
used the tray for reducing with red prussiate and hypo, and
1 14 Library of Practical Photography.
only rinsed out the tray with plain water, sufficient hypo
would still remain in the tray to contaminate the persulphate
solution. In fact, the least trace of hypo would ruin a per-
sulphate bath. Therefore, to insure good results, cleanse your
tray thoroughly, and the best solution to use for cleansing
the tray is one dram of sulphuric acid added to two ounces of
water. Wash the tray thoroughly with this solution, and
rinse with plain water. You may be sure that the hypo and
other chemicals are then removed.
282. You are also cautioned when examining the plate
which is being reduced, to rinse it off under the tap with
plain water, before holding it up to the light, for if any of
the solution remains upon the plate it is apt to run in streaks,
and the reducing will continue, and thereby ruin the plate.
283. Kind of Negatives to Reduce with Persul-
phate.— Dense negatives resulting from over-exposure should
not be treated in the persulphate ammonia bath, for in such
a case you must reduce and clear the shadows as well as the
highlights. The red prussiate of potash reducer is the best
for such negatives. Dense negatives resulting from over-
development of proper exposures, and from under-timed
plates, that have been purposely over-developed in order to
supply all the strength possible in the shadows, should be re-
duced in the persulphate ammonia bath. While the high-
lights alone are to be reduced, yet the entire plate is immersed
in this bath, and the chemical action will be upon the high-
lights only. To apply a chemical that would act upon the
shadows as well, would be ruinous; therefore, the persulphate
should be used for reducing such plates.
284. In order to illustrate more clearly the advantage of
the different reducing agents we present illustration No. 9
with only one-half of the plate treated with red prussiate re-
ducer. If you will note this illustration No. 9, which was
made from a negative that was over-exposed and over-devel-
oped, and then one-half of the plate reduced with red prus-
siate of potash, you will note the half which was not reduced
shows but little of the image, and the part that was reduced
gives a good strong print with clear shadows, soft highlights,
Illustration No. 9
Print from Over-Exposed and Over-Developed Negative,
One-Half of which is Reduced
See Paragraph No. 284
Illustrations Nos. 10 and II
Before and After Reducing
See Paragraph No. 284
General Negative Reducing. 1 1 7
and good detail in both shadows and highlights. The re-
duced portion was completely printed in about fifteen minutes,
while it would require hours to completely print the unre-
duced half and even then it would not produce as good a print
as if reduced. In illustration No, lo, you will find the results
produced by reducing with persulphate of ammonia. Here
the plate had no more strength than was required in the shad-
ows, but the highlights were too dense. The persulphate
has acted upon these highlights alone, with the results as
shown in illustration No. ii.
NATURE OF CHEMICALS USED FOR REDUCING
NEGATIVES.
285. Red Prussiate of Potash (Ferricyanide). — Red
prussiate crystals, when pulverized, become a yellow pow-
der. Action, acid. Must be kept from the light and air as it
will readily decompose. Dissolves slowly. Do not confuse
with ferrocyanide, commonly called yellow prussiate of
potash.
286. Persulphate of Ammonia. — White crystals or
granular. Action, acid. Will decompose readily if allowed
to remain in the air. Dissolves readily in water.
287. Hypo-Sulphite. — Commonly called hypo ( thiosul-
phate of sodium). Put up in crystals and granular form.
Colorless. Dissolves readily.
288. Alum. — White astringent mineral substance. Ac-
tion, acid. Dissolves readily. Put up in crystals and pul-
verized form.
289. Sulphite of Soda. — Transparent crystals, also gran-
ular and dried, (anhydrous). Very soluble in water, two
parts of crystal are equivalent to one part dried, (Anhy-
drous, or granular. Chemical action, neutral or slightly alka-
line. Do not confuse sulphite with sulphate of soda.)
290. Sulphuric Acid, C. P. — Chemically pure. A col-
orless, oily liquid. Commercial sulphuric acid is yellow or
118 Library of Practical Photography.
brown, and should never be used. Caution : — Never pour
water into sulphuric acid, as this would be most liable to
cause an explosion. Always pour the acid into the water.
Coming in contact with the flesh it will burn. Do not con-
fuse sulphuric acid with sulphurous acid.
CO
CHAPTER XI.
LOCAL REDUCING.
PLATES OR FILM.
291. Undoubtedly many negatives are made in which it is
desirable that certain portions of the plate be made a trifle
thinner, yet it would not do to sacrifice the whole plate for a
few minor improvements. By careful application of the re-
ducing solutions, whether it be the red prussiate or persul-
phate of ammonia, the portions of the plate which print too
harsh can be subdued.
392. Class of Negatives that Can Be Improved by
Doctoring, — In landscape, cloud effects, and interior work,
this doctoring is invaluable, for in this way all halation and
objectionable highlights can be subdued, or entirely elimi-
nated. In portraiture, for instance, where you have a red or
tan faced subject gowned in white, there is apt to be great
contrast, unless care has been taken in the lighting;
even then, one when developing, in their endeavor to build
up the face as strong as possible so it will not print black, is
very apt to over-develop the drapery. Then, again, a white
bow in the hair, a blue ribbon, etc., may develop very strong,
and give chalky results. It also happens very often that the
plate is under-exposed, and in forcing the detail in the shad-
ows, the highlights become too dense. All these objections
can be removed, and the negative very much improved by
local reduction.
122 Library of Practical Photography.
293. Doctoring White Drapery. — Great care must be
exercised, else you overdo, or spoil the plate ; still these meth-
ods are successfully employed every day, and practice will
make you perfect. Sometimes in large groups there may be
but one or two subjects in white drapery, and the rest are all
in dark ; usually the white gown is developed a trifle stronger
than you would like, and, consequently, the white drapery
prints chalky, compared to the others. In sucli cases it is
necessary that only these white draperies be reduced. By
careful application of the reducing solution one can improve
many faults in any negative, even with entire groups of sub-
jects all gowned in white, such as bridal parties, graduating
classes, or even single subjects dressed in white. Where the
delicate trimming of lace, etc., is sometimes lost, and there is
little or no detail in any part of the drapery, one can by care-
ful application reduce the harshness and supply detail.
Where the dress is arranged in folds one can accent the shad-
ows more or less by applying the reducer to these parts.
294. In Part First, of Negative Reducing, we de-
scribed, in paragraph 260, the class of plates that should be
reduced with red prussiate of potash. In preparing this In-
struction, reducing portions of the plate only where it will
do no harm to reduce the shadows a trifle also, it is advisable
to use the red prussiate, and your first experiments should be
with such a negative. After soaking the negative in the
hypo bath for ten minutes, apply with a soft camel's-hair brush
the diluted solution of red prussiate of potash to all parts that
need reducing.
295. Strength of Solution to Use. — The reducing solu-
tion must be used diluted, because the action of the solution
begins on the surface of the film, and works its way
through, and, if too strong, in all probability would dissolve
away some of the shadow details before accomplishing the
required reduction in the denser parts of the negative. Too
strong a solution will also work too rapidly for even reducing,
and one is almost sure to produce blotches and spots, instead
of gradually blended results. Great care anust be exercised
lest you touch other parts of the negative, which do not require
Local Reducing. 123
reducing. A good plan is to pour into a saucer a small
quantity of the reducing solution, made according to instruc-
tions (see paragraph 265, Part I), diluting the solution by
adding an equal amount of water. Dip the brush into this
solution, and squeeze out the overflow of the brush on the
edge of the saucer so that there will be but a trifle remaining
on the tip of the brush.
296. Applying the Reducer with the Brush. — Hold
the plate to the light so that you can see through it. If possi-
ble, have the light lower than the plate so that you can hold
the plate almost flat when applying the solution. Before ap-
plying the solution, however, mop the surplus water from the
surface of the plate with a tuft of cotton, or with the ball of
the hand. This will prevent the solution from spreading.
When applying the reducer do not allow it to touch any other
portion except the parts to be reduced, and allow the solution
to remain on the plate only a few moments at a time. After
each application rinse off with water, thereby avoiding the
spread of the reducing solution, and the danger of reducing
too fast. Examine the plates carefully after each application.
After you have applied the weak diluted solution a number
of times, and have not obtained the desired result, apply a
stronger one, working very carefully. It is safer to work
slowly, as your results in the end will be much better, and
there will be less danger of reducing parts that should not
have been reduced.
297. Use Running W^ater to Check Reduction. —
Always have running water from the faucet flow over the
plate as soon as the reduction is carried far enough. This
necessarily requires very quick action on the part of the oper-
ator, or the solution will be left a second too long, and the
reduction carried too far.
298. Avoid Granular Surface by Returning the Plate
to the Hypo Bath. — After the parts are reduced to your
satisfaction, rinse the plate for a moment under the faucet,
and then replace in the hypo bath for ten minutes. This will
insure a good color to the plate, and will produce a smooth
surface instead of a granular effect, which would be the
124 Library of Practical Photography.
result if the plate were not returned to the hypo bath after
the red prussiate had been applied.
299. Applying the Reducer with the Finger, or Tuft
of Cotton. — Another very good plan, especially where you
are reducing white drapery, is to apply the solution with the
finger, dipping it in the solution and rubbing the parts to be
reduced. Here again it is necessary to guard against rubbing
these portions too hard. You should have running water dur-
ing the process, so that you can quickly place the plate under
the faucet after each application. For very delicate work,
however, we advise using a No. 2 camel's hair brush; for
heavier work you can apply the solution with the fingers, or
tuft of cotton. In this way you can reduce strong highlights
on the face, hair and drapery, but you must be exceptionally
careful when applying the solution to the face that you do
not overdo the work. When using the finger rub lightly or
heavily, as may be required, but always bear in mind that it
will not do to rub too hard. The sense of the touch will aid
you in judging the amount of the reducing you are doing, as
the film not only becomes thinner to look through, but really
reduces in thickness. The sense of touch serves as a very
good guide to prevent you from overdoing the reduction, or
injuring the film by hard rubbing.
300. There are times when one would like to blend the
drapery from the strongest highlights to total black shadows.
This can be accomplished very nicely by applying the solution
very lightly to the strongest lights, and gradually heavier to
the parts requiring more reduction. A tuft of cotton is best
for this work, as the reducer must be spread more broadly.
While the majority of the reduction is in the lower portion of
the plate one must occasionally swab, very lightly, the upper
portions, rubbing heavier as you approach the lower parts, so
as to gradually blend them. This blending will require con-
siderable practice to do the work nicely, but when one gets
the knack of doing it any desired result can be obtained. If
the parts you wish to reduce are very strong, and the reducer
does not take hold properly, use a double strength solution.
When using the double strength solution hold the plate per-
Local Reducing. 125
pendicular, and apply to the lower parts, first blending up-
ward. The reducer will then run over the parts to be reduced
the most, and by constantly swabbing with the cotton, streaks
will be avoided.
301. Reducing Plates After They Have Dried. —
When the plate is dry, and you wish to locally reduce it, it is
necessary to first place the plate in plain cool water for ten
minutes. This softens the film, and opens the pores. Then
transfer to the regular hypo bath, and allow to remain for ten
minutes more, so that the pores of the film being open allow
the hypo to penetrate quickly, thereby avoiding stain and
spots, as would be the case had all the film not been evenly
saturated with hypo.
302. After the plate is sufficiently soaked in hypo, it is
advisable to immerse the entire plate in a very weak solution
of reducer for only a moment ( just enough to slightly stain
the film). Then rinse with plain water, and apply the
solution locally, as you require. Finally, when you have
doctored the plate to your entire satisfaction, again immerse
the entire plate in the reducing solution for a moment, after
which rinse off quickly. Then place it again in the hypo bath
for ten minutes, and finally wash for fifteen minutes in run-
ning water. If the negative requires much doctoring, the
reducer may slightly discolor the reduced portions. If
this should occur after the plate is thoroughly washed
immerse it in the clearing bath. ( See paragraph 370 of
Part I.)
303. Reducing with Persulphate. — While most local
reducing can be accomplished with red prussiate bath, yet,
some workers prefer the persulphate for certain class of
plates. In treating with the persulphate reducer. Part I, of
this Instruction, you were told that the persulphate has a
tendency to reduce the highlights without effecting the shadows ;
therefore, this reducer should be used only on plates where
the shadows are already thin enough. Prepare your persul-
phate of ammonia reducer according to instructions in para-
graph 277, Part I. Remember that it is necessary when using
this reducer that the negative be absolutely free from every
\
126 Library of Practical Photograph}^.
trace of hypo. The application of the solution is exactly the
same as that of the red prussiate. After you have reduced por-
tions of the plate as much as you desire, rinse the entire plate
in water. Then place it in sulphite of soda bath ( see para-
graph 279, Part I), after which wash in plain running water,
and place in rack to dry.
304. Applying the Reducer to Films. — The application
of the local reducing solution applies to films as well as plates.
Both are reduced exactly alike. When applying the red prus-
siate locally to film, in order to hold the film perfectly flat,
lay it on a piece of plain glass which has previously been
wet in cold water. The surplus water on the glass and film
will hold the film perfectly flat, while you are applying the
reducer. If the film is of the curling kind, it will not lay flat
by the above method. With ordinary tacks fasten the four
corners to either a card board, or a small pine board, which has
previously been thoroughly soaked in clear water, and while
wet tack on the film.
305. If the persulphate reducer is used, it should be applied
to the film while dry. In event of the film curling, the board
to which it is attached must be dry and not wet. As any
results produced by persulphate can be obtained with the reel
prussiate and many more effects that cannot be produced by
persulphate can be obtained with the red prussiate, which is
easily prepared, and much simpler to manipulate than the
persulphate, it is advisable to use red prussiate for all local
reducing.
306. While the best time to reduce or doctor a negative
with red prussiate is while it is wet, or as soon as possible
after the plate is developed and fixed, yet it is advisable, for
experimental purposes, to use old or discarded plates or films.
These being dry must be treated according to instructions be-
fore reducing. After one has become experienced in the
manipulating of the reducer locally, it should be applied on all
negatives requiring local reduction immediately after the plate
is developed, and thoroughly fixed.
Local Reducing. 127
DIFFICULTIES — REDUCING.
DIFFICULTIES MET WITH IN REDUCING WITH RED
PRUSSIATE OF POTASH.
307. Negative Reducing too Slowly. — Plates or films which have
been fixed in a bath containing alum, acid, or any hardening chemical,
are apt to reduce slowly, and at times not at all. Plates which have
been dried a long time will reduce slowly unless the film on the plate is
thoroughly softened, and this is done by first placing in water for ten
minutes and then transferring to the hypo bath for half an hour. It is
also necessary at times to strengthen the reducing solution by adding
reducing agent. If too much hypo bath was used the reducing agent
would act slowly, as the hypo would overpower and weaken the reduc-
ing agent.
308. Negatives Reducing too Quickly. — If the reducing solution
acts too quickly, it is because the reducing agent used is too strong.
Remedy: Add more hypo solution.
309. Negatives Will not Reduce. — If the negatives will not reduce
place in fresh water for one-half an hour, then into the regular fixing
bath for another half-hour, and reduce with double strength reducing
solution. Use twice the amount red prussiate solution to the regular
amount of hypo.
310. Reducing Shadows too Much. — If the shadows in the nega-
tive are reducing too much you should use the persulphate of ammonia
reducer. Only by careful manipulation, however, can you reduce the
highlights alone with red prussiate reducer. Apply carefully to the
parts of the negative which need reducing. Do not allow any of the
reducing agent to touch the shadows.
311. Negatives Stained a Reddish- Yellow After Reducing. — If
the plate, or film, is stained a reddish-yellow after reducing it is because
the negative was not perfectly fixed before reducing. It was not
allowed to remain in the hypo long enough to remove all the silver
from the plate. If the reducer is applied before the silver is entirely
eliminated it will cause a stain which is almost impossible to remove.
However, the clearing bath (formula for which is given in paragraph
270, Part I, Negative Reducing) will generally improve the color.
312. Negatives Streaked After Reducing. — If the negatives have a
streaky appearance after reducing, it is because they were allowed to
remain in the reducing solution without agitating — rocking the tray —
or if the plate is not thoroughly fixed before reducing it is apt to reduce
in streaks. Remedy: Always fix plates, or film, ten minutes after the
silver, or white, has disappeared, and carefully rock the tray while the
plate is being reduced. i^
128 Library of Practical Photography.
When applying the reducing solution locally, unless great care is
exercised the reducing agent is liable to run on the plate and this
would cause streaks. Remedy: When applying locally place the plate
flat in a horizontal position, allowing the solution to remain on the plate
for only an instant at a time, and rinse under the tap after every
application, and before examining.
313. Negatives Yellow After Reducing. — If the plate is yellow after
reducing it may have been slightly yellow before reducing, and the re-
ducing will make this yellow stain a trifle darker. If the reducing agent
is too strong, or the hypo too weak, reducing is apt to stain the plate.
Generally the alum clearing solution will remove this stain.
314. Removing Yellow Stain from Negatives After Reducing. — If
you find that the clearing bath will not act readily, add a little more
alum and sulphuric acid. Sometimes, however, one may have added
too much acid to properly balance the bath. In such a case the addi-
tion of more alum only to the bath already prepared, will at once start
the plate to clearing. Care must be exercised when adding more alum
or acid. Too much alum will pucker the film, and too much acid will
reduce the plate. Therefore, add only a little alum at a time, and only
a drop or so of acid. Use only chemically pure acid, and ground alum.
315. Surface of the Plate Puckering After Going through Clearing
Solution. — If the surface of the plate has a shriveled- up appearance, it
is because the clearing solution contained too much alum, and the
strong alum puckered the film. Very little can be done to remedy this.
Sometimes soaking in a fairly strong solution of carbonate of soda, and
then washing thoroughly, will bring the film back to its proper form.
316. Negatives Reducing in Clearing Solution. — If the negative
continues to reduce in the clearing solution, it is because the clearing
bath contained too much sulphuric acid. When you first place a plate
in the clearing solution allow it to remain for a moment only, and then
rinse it under the tap before examining. If you find that the clearing
bath is reducing the plate add more water before you place the nega-
tive back in the solution.
DIFFICULTIES MET WITH IN REDUCING WITH PERSUL-
PHATE OF AMMONIA.
317. Persulphate of Ammonia not Reducing. — If the persulphate
of ammonia bath is prepared properly, and is of good quality, it reduces.
If it acts slowly strengthen by adding more persulphate. (See para-
graph 377, Pari I.)
Local Reducing. 129
318. Persulphate of Ammonia Bath Reducing too Quickly. — If the
persulphate of ammonia reducer acts too quickly, it is because the solu-
tion is too strong. (See paragraph 275, Part I, Negative Reducing,)
Always make up the bath just before you are going to use it.
319. Parts of the Negatives Reduced with Persulphate Stained. —
If parts of the negatives which have been reduced are stained, place the
plates in the clearing bath composed of alum and sulphuric acid. Pre-
vious to this, however, the plates should have gone through the sulphite
checking bath. Be sure that the negatives are properly fixed and
washed, and there will be no stain after reducing.
320. Plates Very Glossy After Reducing. — All plates will appear
rather glossy after reducing, and are, therefore, harder to retouch and
etch. The cause of this glossy appearance is that the reducing solution
acts on the top of the film, and actually cuts away a portion of this film.
At the same time it acts as an astringent, and draws the little globules
of gelatine together, thus causing the hard, shiny surface. This can be
overcome to a certain extent by soaking the plate for a few minutes in
a carbonate of soda bath, about sixty hydrometer test. This will open
the pores, and there will be very little gloss.
321. Confining Solution to Only the Parts to be Reduced.— To
avoid reducing other parts than those you desire reduced, mop the
surplus water from the parts to be reduced. The solution will then
attack the film quickly. Work carefully, applying only a little reducer,
allowing it to remain on the parts to be reduced for only an instant at
a time. Rinse after each application, and do not use too strong a solu-
tion. It is necessary that you act quickly. You must think and act at
the same time. Practice, and practice only, will enable you to overcome
this difficulty.
^
CHAPTER XII.
UNIVERSAL DEVELOPING.
322. In our previous Instruction on Ordinary Develop-
ing we dealt principally with the use of necessary chemicals,
and the manipulation of the different solutions in order to pro-
duce certain results. The formula for developing, given in
this instruction, is intended for all classes of work, and should
be universally employed for general portrait or commercial
photography.
323. After numerous* experiments with the formulae and
instructions given in former lessons, you : should have a fair
understanding of the use of the diffeient chemicals em-
ployed, and the advantage of altering the quantities of chemi-
cals in the different solutions, from time to time, to suit the
plate you are developing. Further, you should be advanced
sufficiently to appreciate the advantage of the formula given in
this instruction for rapid development of all classes of expos-
ure, with little or no change of the developer, and yet produce
the very best of results.
324. The simplest formula that one can employ, and yet
obtain good results is always the surest and best. By ap-
plying the formula given in this instruction to all your future
general work you will produce very uniform negatives, and
with the slight altering from time to time to suit local water
conditions every obstacle can be overcome.
325. You should profit, of course, by your previous ex-
perience with Ordinary Developing, and by applying the
same method with the formula called for in this instruction
superior results will be secured. This formula you will notice
11-8 181
132 Library of Prticiical Photography.
is divided into four solutions, the principal object of which is
to have your normal developing agent (pyro) ripen in solu-
tion before using. If you were to prepare a gold bath for
toning prints and use it immediately, without permitting it to
set and become thoroughly mixed with the water, thus ripen-
ing the bath, it would work harsh and bleach the highlights in
the prints ; whereas, by allowing the gold and alkali to mix
gradually with the water, and become thoroughly ripened,
the bath works more evenly and smoothly, producing
greater roundness, and a much more delicate effect.
As it is with the toning bath so it is with the developing
solutions.
326. If your developing agent is mixed from a concen-
trated stock solution directly with the accelerators of a less
strength and then still diluted with water and immediately
used for developing, the strongest chemical will attack the sen-
sitized plate first. In this case the strongest chemical being
your developing agent ( pyro ) , the highlights are attacked,
and if the plate is fully-timed the plate has lost its roundness
before the accelerators have been sufficiently mixed with the
pyro to supply the required softness. Thus, many times,
plates that are really properly exposed, develop as though they
were over-timed, and the same is true of under-exposures. The
strongest chemical (pyro), attacks the highlights, and clogs
the shadows before the alkali, or accelerator, has an oppor-
tunity to soften and open the pores of the film sufficiently to
permit the developing agent to build them up, and assist in
supplying detail.
327. This obstacle is overcome by permitting the devel-
oping agent (pyro), as well as the accelerator, to ripen be-
fore using. This you do by preparing your developer in four
solutions and reducing the concentrated pyro stock solution
to the strength required, ready for use, which proportions are
equal to those of the sulphite and carbonate to supply a prop-
erly balanced developer. Each solution being prepared for
some time in advance, all are well ripened, ready for immedi-
ate use, without adding water to the developer until just be-
fore using. If water is added at all it affects all the three
Universal Developing. 133
chemicals alike, as all are diluted to their proper proportions,
and are perfectly balanced.
UNIVERSAL DEVELOPING FORMULA.
328. Prepare your developer as follows : —
Stock Solution, No. i.
Water 6 ounces
Sulphuric Acid, C. P ^ dram
Pyro I ounce
Note. — If softer results are desired use water twelve ounces in place
of six, the other stock solutions remaining as they are, as the object is
to change the strength of the pyro only.
Mix these chemicals in the order given. Add the acid
gradually to the water. Never add the water to the sulphuric
acid. By adding the pyro last you avoid early discoloration
of this stock solution.
329. The sulphuric acid, used in Stock Solution No. i,
will preserve the solution from discoloring, and it also has a
tendency to retard the development, and will hold the shad-
ows clear and free from fog — sulphuric acid contains a frac-
tion over ninety-two per cent, pure acid and, therefore, must
not be used in excess quantities. Nitric acid may be substi-
tuted, if one so desires, but as the latter contains only sixty-
eight per cent, pure acid, one dram should be used in place
of a half dram of the sulphuric. As nitric acid has less re-
tarding qualities (being a weaker acid), it is recommended for
slow developers. As this formula is for a rapid developer,
we recommend sulphuric acid.
Stock Solution No. 2.
330. Procure a thirty-six-ounce bottle. Into this pour two ounces o£
Solution No. i, and add thirty-two ounces of water.
Stock Solution No. 3.
Sulphite of Soda, 40 hydrometer test, or by weight.
Sulphite of Soda (anhydrous) i ounce
Water 13 ounces
134 Library of Practical Photography.
Stock Solution No. 4.
Carbonate of Soda, 20 Hydrometer test, or if by weight,
Carbonate of Soda (anhydrous) i ounce
Water 23 ounces
If soda crystals are used you will require double the weight.
331. Use only the very best of chemicals. We would rec-
ommend anhydrous sodas C. P., and advise hydrometer test
in preference to weight. Prepare all stock solutions in the
order given.
DIRECTIONS FOR USING.
332. Take of Soiution No. 2, four ounces; of Stock Solu-
tion No. 3, two ounces; of Stock Solution No. 4, two ounces,
— making eight ounces of solution. Before using pour this
combined solution back and forth from the graduate to a clean
tray, to thoroughly mix all of the chemicals. After placing
the plate in the tray, pour the solution over the plate, and be
sure to cover the entire plate with one sweep, as the action of
this developer is so rapid that unless all parts of the plate are
covered with the first sweep, there will likely be streaks and
lines in the completely developed negative.
333 When making an exposure, whether portrait, land-
scape, interior or exterior, you must at all times expose for
the shadows; that is, you must give sufficient exposure to
supply the required detail in the shadows, but when develop-
ing the plate you must develop for the highlights, making due
allowance for fixing.
334. You will find with this developer the plate, if prop-
erly exposed, will develop quickly, and the image will grow
gradually. The shadows will develop along with their
proper relations to the highlights, and when the latter are
developed to the point you desire, your shadows will be
crisp and round, with plenty of detail.
335. The color of the plate is governed by the strength of
the sulphite. Water is subject to several chemical changes
during the year. Usually in the spring the water becomes
Universal Developing. 135
infected with more or less vegetable matter, and there are
other times when the water becomes more alkali than usual.
You will realize this when your plates, after washing,
are of a more or less yellow color — there being more al-
kali in the developer than enough to balance the de-
veloper. If the plate becomes too yellow you should in-
crease the strength of the sulphite; if the plate becomes too
gray reduce the strength of the sulphite. Allow the carbon-
ate of soda to remain 20 Hydrometer test always, and regu-
late the color entirely by increasing or reducing the strength
of the sulphite.
336. For Seeds, Stanley and Standard plates use the de-
veloper according to this formula. For Hammer plates use
three ounces of No. 2 (pyro) in place of four ounces, and
add one ounce of water to the developer For Cramer plates
use five ounces of No. 2 (pyro), in place of four ounces, and
add one ounce of water to the developer.
337. From the fact that Seeds plates are very heavily
coated, they must be carried farther in the developer than
other plates. The reason you use less pyro for Hammer
plates is that they are thinner coated, and work with greater
contrast, consequently, to obtain soft effects they do not
need the same amount of pyro, nor as strong contrast in the
lighting of the subject as the other brands which are thicker
coated, in which the contrast must be built up. Pyro is a
contrast producer in developing. The emulsion of Cramer
plates is such that it requires a little more pyro to give
the desired contrast on this brand of plate. By adjusting the
developer, according to formula, and instructions given
herein, you can obtain every quality that exists in any brand
of plates.
IMPORTANT NOTES.
338. With this developer, working as it does quite rapidly,
care must be exercised that you do not over-develop. Ex-
amine the plate frequently. It is a good plan to provide
yourself with a washing tank; fill it with water, and when
you judge a plate very nearly developed, place it in the tank
136 Library of Practical Photograph}).
of water, and allow it to remain for fifteen minutes. If you
have other plates to develop, proceed and develop all you
have, but place them all in the tank of water for a short
while before transferring into the fixing bath. You will be
surprised to discover how much the plate will develop in the
water, and the developing will not be harsh, but soft, mellow
and round. The half-tones will be full of detail — the shadows
crisp and snappy.
339. In case of a plate lagging in the developer, indicating
under-exposure, place it in the tank of water for ten minutes
at a time, then return it to the developer for a while, and if
it still appears weak, again return it to the tank of water.
The temperature of the water should be about sixty-five
degrees. Many times a considerably under-timed plate
can be treated in this way, and a splendid negative made
of it.
340. In case of over-exposure — the plate flashing up quite
quickly — it is advisable to provide yourself with a tray of
water containing several drops of bromide, and place the plate
in this solution for five minutes. This will restrain the shadows,
and when returned to the normal developer the plate will
develop evenly and round up, becoming more crisp as it con-
tinues developing. In case the plate was very much over-
timed, and not checked soon enough, then you will need
to develop quite dense, and finally reduce with red prussiate
reducer. For formula, see instruction on Reducing. Nega-
tives that are just a little dense, and perhaps a trifle hazy, can
be greatly improved — the shadows cleared and strengthened —
by immersing the negative, after thorough fixing, for a
few minutes in a weak red prussiate of potash reducing
solution.
341. Another pyro formula which may be used for exceed-
ingly soft effects : —
Stock Solution No. i.
Water 16 ounces
Sulphuric Acid , . . . . 10 drops
Pyro I ounce
Universal Developing. 139
Stock Solution No. 2.
Sulphite Soda, 60 hydrometer test, or, if by weight.
Sulphite Soda ( Anhydrous) 2 ounces
Water 18 ounces
Stock Solution No. 3.
Carbonate Soda, 50 hydrometer test, or, if by weight,
Carbonate Soda 2 ounces
Water 18 ounces
For use take,
No. I I ounce
No. 2 I ounce
No. 3 I ounce
Water 16 ounces
The temperature of all solutions should be as near normal
as possible, sixty-five to seventy degrees Fahr,
ALUM HYPO BATH.
In w^arm weather, or warm climates, the following alum
fixing bath may be used in place of the plain hypo and
water : —
A Water 96 ounces
Hypo 2 pounds
B Sulphite Soda (Anhydrous), 4 ounces, or, if in crystals,
double the amount.
Powdered Alum 6 ounces
Citric Acid i ounce
Water 64 ounces
When both solutions are thoroughly dissolved, pour B into A
slowly, while stirring rapidly.
140 Library of Practical Photography.
DIFFICULTIES — UNIVERSAL DEVELOPING.
342. Developing Heavy Shadow Lightings. — In developing shadow
lightings, in portraits or views containing dense shadows requiring de-
tail, you must strive for clearness of the shadows, and softness of the
highlights. This is controlled before development by the amount of
developing agent that you are using. If you find the highlights build-
ing up strong — becoming dense, practically no half-tones showing in
them — reduce the strength of your developer by adding water. Often-
times if the exposure is short, place your negative in a tray of fresh
water. If the negative is very much under-timed prepare a new devel-
oper, using one-half the amount of the developing agent (pyro), the
regular amount of carbonate and sulphite, and double the amount of
water. Generally this formula for universal developing, if the light-
ing and exposure have been anywhere near correct, will develop
properly without altering.
343. Developer Discoloring After Having Been Prepared Only a
Short Time. — If the water you are using in your pyro stock solution
is strongly alkali, it will cause your stock solution to discolor quickly,
and it might be necessary to acidify the water, neutralizing it, before
preparing this stock solution. This you can do by adding a few drops
of sulphuric acid. But first test the water with blue and red litmus
paper. If the water turns the red litmus paper blue, you will know
that it is strongly alkali. If, however, it does not change the color of
either litmus papers, you will know it is neutral. If the water does
turn the red litmus paper blue, then you will need to acidify it by add-
ing a drop at a time of sulphuric acid until it becomes neutral.
344. When you have neutralized the water, then add in addition the
amount of acid given in the formula ; finally add your pyro. Keep your
pyro stock solution in a tightly corked bottle, if possible, a brown or
yellow bottle, and store in a dark, cool place. When you are prepar-
ing for developing, first pour your pyro solution in the graduate, next
add your sulphite, then your carbonate. All stock solutions should be
shaken before using, especially the pyro stock solutions, (so as to keep
the acid thoroughly mixed with the pyro.) If your stock solution does
not discolor rapidly there is no necessity for neutralizing the water.
345. Negatives Drying with a Coarse Grain. — This is some-
times due to the carbonate of soda being too strong, or prolonged de-
velopment, or if the negative is gray and grainy your sulphite is also
too strong. Reduce the strength.
346. Shadows Fogging During Development.— This trouble is
generally found in under-exposures where you had altered the developer
by reducing the amount of pyro, thereby producing a developer too
Universal Developing. 141
strong in sodas, both sulphite and carbonate, more especially, however,
carbonate. The latter if used in excess of a sufficient amount to nicely
balance the developer is sure to fog the shadows. Extreme under-
exposure requiring prolonged development is also apt to fog the shad-
ows. In such cases immerse the entire plate after fixing in a weak red
prussiate reducing solution. This will clear it.
347. Negatives too Strong in Color — Yellow. — Either your sul-
phite of soda solution has deteriorated by becoming old, or it is not
strong enough. Sometimes sulphite of soda solution that has been made
up for a considerable length of time, while it may test the same strength,
has lost the chemical action necessary to prevent the pyro from staining
the plate. Discard this sulphite, and make up a new solution. The
amateur who only develops occasionally should make up small stock
solutions. Both sodas should be kept in tightly corked bottles. Yel-
low color may be removed from negatives by immersing in alum
clearing bath. See formula in Instruction on Reducing.
348. Testing Old Sulphite of Soda Solution. — Place a small quantity
of your pyro solution in your graduate ; next add a small quantity of
sulphite, then add the same quantity of carbonate. If your developer
turns dark, and refuses to clear up, as it should if the sulphite was fresh,
you may be certain that the sulphite is too old and deteriorated. In
making this test, use the same proportions that you would in preparing
your developer for developing.
349. Negatives which Appeared Sufficiently Developed, Very Thin
After Fixing. — If your negative is of a scene with heavy shadows, or a
portrait of Rembrandt Lighting, the negative should be thin, and while
it may appear too thin you will find that it has sufficient strength for
good printing quality. If the highlights of the negative are very thin
it may be possible that you are under-developing ; therefore, you must
experiment. Carry the developing a trifle further, and then watch
your resulting prints.
350. Proper Detail in Shadows. — While this is governed greatly by
the lighting, the detail in the shadows is often lost in the developing,
and in the improper preparation of the developer, or from not handling
the negative correctly during development. If you find that the high-
lights are building up strong, it is possibly due to the fact that your
lighting was contrasty, or you under-exposed the plate. It is, therefore,
necessary that the strength of the developer should be reduced and this
you can do by adding water to the developer, thus treating the plate as
under-exposed.
351. Plate Inclined to Develop Contrasty. — This difficulty is gener-
ally caused by either contrasty lighting, or under-exposure. Treating
the plate for under-exposure during development — weakening the de-
veloper— will enable you to produce softer highlights, and, therefore,
at the same time build up the shadows, and produce less contrast.
352. Securing Half -Tones in Highlights. — If the lighting is con-
142 Library of Practical Photography.
trasty, even though the plate is fully exposed, the highlights will de-
velop up exactly as they are lighted, and you lose practically all the de-
tail. This is not the fault of the developer, but of the lighting. Subdue
your lighting. You can improve a contrasty lighting in the developer
by reducing the strength of your developer — adding water. This will
give the shadows a chance to build up, and at the same time prevent
the highlights from becoming dense, and will enable you to produce
detail and half-tones.
353. Plate Developing Flat. — In portraiture this is due to flat
lighting, or over-exposure. If the plate develops up very flat and your
subject was properly lighted, and the plate properly exposed, it is be-
cause you have diluted your developer. Use a normal, full strength
developer. If your plate is over-exposed, treat as such in development,
and you will overcome this flatness, and produce more contrast. (See
Instruction, Developing Over-Exposures.)
354. No Detail in Highlights. — This is due either to contrasty
lighting, or over-development. Watch your plate carefully during de-
velopment, and make the changes necessary in the developer to control
detail in highlights. If the plate is over-exposed, add bromide, or
place the plate in old developer. If it is a contrasty lighting, plate ex-
posed about right, reduce the strength of the developer, by adding water.
355. Oftentimes it is a good plan, in this case, to place the plate
directly into a tray of fresh water, and allow it to remain five or ten
minutes, and then return the plate to a developer which should be only
about half as strong as the developer you had been using, and you can
reduce the strength by adding water. If the lighting and exposure are
correct, and the highlights clog up so that there is no detail, this will
indicate that your developer is too strong. Immediately reduce it by
doubling the quantity of water. One should always strive to have the
lightings correct, and never depend on altering the lightings in the
developing.
356. Retaining Soft Detail in Shadow. — In case of contrasty light-
ings developing hard, and you are unable to produce the desired soft-
ness by manipulation, you should over-develop and after thoroughly
fixing the negative reduce the entire plate until the highlights appear
sufficiently soft, with sufficient strength, however, to give snap and
brilliancy. The after reducing will also apply to plates that were prop-
erly lighted, but over-developed. By being careful not to allow your
highlights to build up too strong, you will produce soft detail in the
shadows. Too strong a developer will produce strong highlights and
transparent shadows. Dilute the developer in order to secure softness.
Under-exposure would produce strong highlights, and deep shadows.
Dilute the developer with water. Over-exposure would produce dense
highlights and flat foggy shad<=iws. Over-develop and reduce with red
prussiate.
CHAPTER XIII.
SPECIAL PYRO DEVELOPING FOR
COMMERCIAL PHOTOGRAPHY.
357. By employing the methods for developing given in
this instruction, one can overcome many obstacles, and pro-
duce successful photographs which, with ordinary developing,
would be impossible.
358. Exposures under conditions which would ordinarily
be considered impossible, can be obtained, and good
negatives produced by the method of special development.
In Part I of this instruction we will treat with Com-
mercial Photography entirely. When making general
exterior views, how often do we see pictures of scenes
where, under a high sun, foliage and mountain tops are
drowned into harshness, or even flatness, without any
attempt at preserving the atmospheric eflFects visible. The
haze in the distance, which is most beautiful to the eye,
is lost entirely in the picture. Why ? Because no special
effort has been made to retain it. The hills instead of show-
ing feeling and care are hard as stone. The haze is mere fog
without atmosphere. All the most beautiful effects that are
true to nature can be preserved, and it is these effects that
make the picture interesting, and it is the object of this in-
struction to teach you how to retain them in every exterior
that is out of the ordinary, and beyond this means of preserva-
tion with ordinary developing.
148
144 Library^ of Practical Photography.
359. In interior photography we find many instances where
it would seem absolutely impossible to obtain satisfactory re-
productions of the view as it appears to the human eye. For
instance, photographing interiors of churches with windows
glazed with pictured glass which adds so much to the appear-
ance of the structure. There may be light walls with dark
trimmings, old mission pews, or they may be to the other
extreme, all finished in white enamel and white marble,
which make them still more difficult to reproduce photo-
vP graphically.
360. The photographing of the beautiful stained windows
in clear detail, and at the same time retaining all the values of
the dark trimmings, furniture, etc., seems difficult. Usually
with non-halation plates one can produce fair results, yet there
is always something lacking. The picture has not the snap,
for while the halation from the light entering through the win-
dows has been fairly well overcome, yet the life is absent. It
must be understood that the use of non-halation plates is by
no means to be discouraged. They are of great assistance,
but by this special development greatly improved results can
be obtained. You will not only retain the benefit of the
double coated non-halation values of the plate, but will aid the
plate employed in preserving and registering more accurately
the view as it normally appears.
361. The photographing of interiors of the home admit-
ting windows into the view is really important in making
the room appear cheerful. The lace curtains and decorations
generally with the strong light entering through the window,
naturally over-exposing these portions would, if treated in
the ordinary way, produce nothing but a haze and mist.
While by the special development you can retain every thread
of the design and figure in drapery and curtain as well as a
clear view of the sash and window-frame, and at the same
time obtain clear detail with splendid atmosphere throughout
the room.
362. In the photographing of shops, public halls, and in
extreme cases the photographing of difficult objects such as
machinery which is stationary and cannot be removed to a
Interior Made with a Non-Halation Plate, Ordinary Development
The Same Interior Made on an Ordinary Plate, with Special Development
Illustration No. I2
Example cf Overcoming Halation in Interior Photography
See Paragraph No. 364
special P^ro Developing. 147
more favorable light; and where in many cases the only illum-
ination obtained comes from the side or rear, the windows
which admit this one source of light must be taken into the
view. By the ordinary method of developing, even with
especially prepared plates, the results under these conditions
would be very unsatisfactory and the worker would almost
consider it impossible to produce a good presentable pic-
ture of his object or view. By this special method of de-
velopment all this is overcome.
363. It is a fact that any effect that is visible to the hu-
man eye can be retained in the picture by proper exposure
and development.
364. Illustration No. 12 is a representation of such a view
as one would be apt to believe impossible to secure without so
much halation that the interest of the view would be lost. This
picture becomes more interesting as an illustration in this
instruction for the reason that it was made by one of our
students after making a miserable failure of the same view
by ordinary method of developing.
METHOD OF DEVELOPMENT.
365. The entire success of this method of development lies
in sufficient exposure, and as the latitude as to extreme ex-
posure is so great we must strive only to give full time, as
any reasonable amount of over-exposure can be treated in the
development of the plate. In the wet plate days we had less
difficulty with these obstacles than we have with the dry
plate. Why? For the reason that the emulsion of a wet
plate was not -^ as sensitive to white light as an ordinary dry
plate to-day ; consequently, there was more latitude to the ex-
posure.
366. Next to the wet plate we have the process plate, or
the lantern slide plate, all of which are extremely slow plates.
For the lantern slide we require the clearest plate possible.
The lantern slide must be absolutely clear and free from fog —
shadows must be transparent. With the extremely rapid
plate this would be impossible to produce except where the
148 Library of Practical Photograph}).
most accurate exposure is given, and even then the results are
not as satisfactory nor uniform. While the extremely slow
plate is superior for quality, yet for general commercial work
the slow plate would be impracticable. In many instances
quite rapid exposures are necessary to obtain certain
results which could not be obtained with the slow
plate, and therefore the most rapid plate must be
employed and a means of producing the same results,
as is possible with the slow plate, must be accomplished
in the development.
3670 As stated in the forepart of this instruction, the en-
tire success of special development rests in the exposure.
You must time for the most dense shadows, and time them
fully; a little over-time will do them no harm, as the over-
time can be cared for in the development. By timing for
the most dense shadows with this development the highlights
will care for themselves, for you treat them in the developer
so as to preserve them.
368. A good guide for exposure would be as follows : —
Where you would ordinarily give ten seconds, with this
method give from thirty to forty seconds' exposure, etc.
All the detail in the most dense shadows must be supplied
by the exposure, the rest you obtain in the developing.
369. The slow process of developing, applied by this
method, will, with a full- timed exposure on a fast plate give
you the same excellent results as a long exposure would give
you on a slow plate in which the action of light upon the
plate is so slow that it does not fog the plate. With a slow
plate developed in a normal developer all chemicals act
equally, for there are no great differences to overcome, while
in the fast plate there are enormous differences in the effect of
light between the strongest highlights and the most dense
shadows. In severe cases, by this method of timing fully the
most dense shadows, the highlights would be extremely over
timed; therefore, in order to give us a well-balanced negative,
we must restrain the highlights during development, and hold
them in check until the shadows are fully developed.
special Pyro Developing. 149
DEVELOPING FORMULA.
370. Stock Solution No. i.
Water 24 ounces
Pyrogallic Acid i ounce
Sulphuric Acid 8 drops
Stock Solution No. 2.
Sulphite Soda (hydrometer test 70).
Stock Solution No. 3.
Carbonate Soda (hydrometer test 40).
371. To develop take one ounce of No. i, one ounce of
No. 2, and ten to twelve drops (no more) of No. 3, and add
twelve ounces of water.
372. Before beginning to develop let us consider again
the nature and objects of each chemical used in developing.
Stock Solution No. i is your pyro solution, or (developing
agent) strength producing agent. Stock Solution No. 2,
sulphite soda, is your color regulating chemical. Stock So-
lution No. 3, carbonate of soda, is your detail- producing
chemical.
373. In ordinary developing if you desire more contrast
you would increase your pyro, because pyro being your de-
veloping agent gives you strength, builds up your highlights.
If your plate developed yellow in color, you would increase
your sulphite of soda in order to retain the proper color. If
your plate lacked detail, and developed too contrasty, you
would add carbonate of soda, because it opens the pores of the
film and permits the pyro to get to the shadows, and, therefore,
is your detail-producing chemical. For this method of devel-
oping we have provided by prolonged exposure all the neces-
sary detail, so all we require is to retain this detail and produce
the proper strength. It is absolutely impossible to develop a
plate without at least some alkali, or detail-producing chemi-
cal. It requires but a very small amount of carbonate of soda,
150 Library of Practical Photography.
yet some of this chemical must be used, or the pyro will not
attack, and the plate will not develop.
374. Ordinarily, we would desire to have the pores of
the film open up as it were, by means of carbonate of soda,
thus permitting the pyro to act and build up, and supply the
strength necessary. In this case, however, we do not desire
the pores to be open, as we are already supplied with the de-
tail by the exposure ; therefore, we use only a few drops of
the detail-producing chemical, merely sufficient to allow the
pyro to develop the plate. The development will be gradual,
and the shadows and highlights will build up gradually in
their proper proportions, the plate remaining clear and crisp
throughout the development.
375. When first placing the plate in this solution, it may
require some three or four minutes before the image will
appear. If it does not appear by this time, add three to five
drops more of the carbonate of soda, or Solution No. 3.
These additional drops of alkali will start the plate develop-
ing quite freely. After a few more minutes add a few drops
more of No. 3, and again from time to time, if necessary,
until the plate is fully developed.
376. You must bear in mind that you have added so little
of this solution that the pores of the film are not filled with
the carbonate of soda, none of your lights or shadows are
clogged or choked; your plate is clear throughout, and your
developing has been deeper and more solid, and, therefore, is
really developed farther than if it were developed in the ordi-
nary way.
377. Should you find after developing for some time that
the plate is apparently fully developed with good, clear detail
in the shadows, yet lacking snap in the highest lights, and
continuous developing does not seem to build them up,
then pour off this solution and make up a normal developer
according to regular formula for universal developer. (See
paragraph 328.)
378. Immerse the plate in this normal developer for only
a moment, examining very closely, for in the normal developer
the plate will build up very rapidly. When you secure the
special Pyro Developing. 151
proper strength which should not require more than a min-
ute or two at the most, rinse the plate in plain water, and
finally fix in a plain hypo bath free from other chemicals.
379. As the developing of the plate by this method is
quite slow, requiring fifteen to twenty-five minutes, avoid un-
due exposure to the ruby light, as you are apt to fog the plate
by long development in too strong a light. It is advisable to
cover the tray during development and only uncover when you
wish to examine it. These precautions must be taken in or-
der to insure perfect success With care and patience the
most beautiful results can be obtained.
II— 9
CHAPTER XIV.
SPECIAL DEVELOPING OF WHITE DRAPERY
PORTRAIT NEGATIVES.
380. The object of this Instruction is to train you in the
method of producing the most beautiful chemical effects ; how
to preserve the relative value of flesh and drapery ; how to
preserve every effect visible on the ground-glass and ' ' get it
in the negative." Any combination of colors can be photo-
graphed, and their different color-values preserved, and by
this method of developing the most beautiful chemical effects
may also be obtained in white or black drapery.
381. This method of developing is especially effective
where there is black or red hair to contend with. The dry
plate is more sensitive to white drapery than to the complex-
ion or dark hair. When making the exposure, the white drap-
ery attacks the plate first, the shadows in drapery next, and
lastly flesh and hair. White drapery, therefore, photographs
quicker than the flesh.
382. Many operators in their eagerness to save the drapery,
under-time the face and hair, or they may time long enough
for the flesh, hair and shadows, and entirely ruin the drapery
by over-exposure and improper development. One rule must
be positively adhered to in order to make a success of this
method of developing: You must time for your most dense
shadows and time them fully. The highlights will care for
themselves, for you treat them in the developer so as to pre-
serve them. You can improve subjects gowned in white
drapery, in the lighting, by diffusing the strong lights, but
never by Mnder-timing the plate. Usually when the light
158
154 Library) of Practical Photography.
on the drapery is diffused sufficient to balance the light on the
face, the drapery is flat and lacks snap.
383. Over-timed white drapery with ordinary developing
of the plate will give you flat results also, but by following the
instructions given you will not only preserve your drapery, but
you will also retain the values of the flesh and hair. Portraits
of brides, or subjects gowned in soft drapery, aged persons,
men with heavy white beards, heavy wrinkles, etc., should be
treated and developed with this special developer.
384. Exposures of nervous people, or infants, cannot be
easily handled with this special development, for the reason
that you must make quick exposures of such subjects to avoid
their moving, and as you must at least double the ordinary
exposure when applying this method, you would not be able
to obtain sufficient exposure for successful development.
The main secret of successful development by this method,
and the most important consideration in order to produce
the proper results, lies in the exposure.
385. You must give plenty of time, exposing long enough
to obtain proper detail in the most dense shadows. The shad-
ows being fully-timed will give you very soft effects when
properly developed. A good way to judge the proper time
is as follows: —
386. Where you would ordinarily expose four seconds, for
this method of developing you should give at least six sec-
onds, and if black backgrounds are used double the ordinary
exposure, or eight seconds will be better. You must supply
your detail by the exposure. The rest you obtain in develop-
ing. The slow process of developing, which is applied in
this instruction, will, with a full exposure on a fast plate,
give you the same excellent results as a long exposure would
give you on a slow plate in which the action is so slow that a
long exposure does not fog the plate. The emulsion of a slow
plate has more the speed of a slow bromide paper on which
the action of light is slow, and, therefore, long development
does no harm. Such plates are too slow to use for portrait
work, and are generally used on lantern slides, where the
most delicate lights must be retained, and the different color-
o6? '0{<i udEjSBjB J aag
£1 'o^ uopBajsniii
White Drapery Portrait Negatives. 157
values carefully preserved, but the long exposure necessary is
not objectionable for this kind of w^ork.
387. Slow plates are also used extensively for copying, as
they produce the best results, and of course quick exposures
are not necessary. For portrait work, in order to retain ex-
pression and avoid moving of the subjects, a quicker exposure
must be made. To accomplish this and retain the same rela-
tive color value that a slow plate would give, a faster plate is
used, which will be fully exposed with half the time neces-
sary for a slow plate, and when developed according to the
special formula, will give practically the same results as the
slow plate requiring a much longer exposure.
388. But even the fast plate must be timed fully, and for
white drapery almost double the regular time must be given.
With ordinary development this would be entirely too much
and would produce a flat negative. But as you secure your de-
tail in the exposure, you must time for the shadows, which
must be as fully-timed as the highlights, and then treated with
the special developer. For formula and method of develop-
ing see paragraph 370, which should be read very carefully,
and thoroughly understood before applying.
389. In portraiture there are many obstacles that can be
overcome by this method of development, that would be im-
possible with the ordinary method.
390. The slow process of development permits one to
build up locally any parts that seem to lag in the developer.
For instance, if the hair is of a very dark color, or the shad-
ows in drapery a trifle heavy, or the detail in black feathers on
a hat lag a trifle in the developing, by dipping the finger
in a weak solution of carbonate of soda, and applying to
the parts you wish built up, will cause them to develop
more rapidly. The least amount of carbonate will attack
the parts applied almost instantly ; therefore the carbonate
must be applied cautiously, and the solution must be diluted,
but by proper manipulation any desired result can be obtained.
After some little practice one will learn to appreciate the
extraordinary value of this method for special work. See
Illustration No. 13, of portrait developed by this method.
158 Librar]) of Practical Photography.
391. The principal four points to remember for the suc-
cessful application of the special development are : —
392. First. — You must give full time to the most dense
shadows. Try to over-time a trifle — it will do no harm —
but to under-time will result in total failure, for if you under-
expose, then you would need to open the pores of the film by
applying more alkali, or carbonate of soda. As the alkali acts
on the entire plate it forces the highlights, and this is what
you want to avoid. By this method the highlights are checked
by lack of alkali, and the shadows build up equally with the
highlights ; so remember and time fully.
393. Second. — You must use the normal amount of pyro,
and the normal amount of sulphite of soda, thus holding these
two chemicals perfectly balanced.
394. Third. — Use only enough of carbonate of soda to set
the pyro and sulphite to action, usually ten drops is sufficient
for this.
395. Fourth. — Use double the amount of water usually
used in ordinary developing. The water aids in supplying
the mellow, round and crisp eff"ect in the negative. Do not
hurry the development. This is not a commercial devel-
oper ; you are after quality, and in order to obtain the very
best quality you must use care, and do not expect the image to
appear for at least two minutes. If it does not appear by this
time, a few drops more of soda should be added. When add-
ing more carbonate of soda, bear in mind that this alkali opens
the pores of the film and permits the developing agent, pyro,
to act, and as the pyro acts on the parts of the plate exposed
the longest — which are the highlights — the more carbonate
of soda used the quicker the plate will develop ; and if too
much is added the highlights are apt to become choked before
the shadows have had time to build up and strengthen. There-
fore, by using a very small amount of carbonate, and the regular
amount of sulphite, which is a neutral soda, you restrain
the highlights, and permit the pyro to attack the shadows
equally with the highlights, and gradually build them up to-
gether. Should the shadows be insufficiently exposed you can
White Drapery Portrait Negatives. 161
not force them, and the result would be a very poor negative ;
therefore, ample exposure is essential.
396. By following the above instructions to the letter you
cannot fail to produce the most beautiful results that it is
possible to obtain by any known method of manipulating the
chemicals.
397. It may require several trials before one will be able
to manipulate the developer, and obtain all the quality there
is in the plate, but by patience and care, and a little practice,
one will soon learn to produce in the negative every effect that
is visible on the ground glass, even to the most minute detail.
It is not advisable to use this method of developing for all
purposes, but only for special work where it is convenient to
apply it. For general commercial work we would recom-
mend the Universal Developing.
DIFFICULTIES— SPECIAL DEVELOPING.
398. Development Slow. Image Over Five Minutes in Making Ap-
pearance.— If the plate has been sufficiently timed the image should
begin to appear within two minutes, even though an extremely small
quantity of carbonate has been used. If the developer is too cold the
image will be very slow in appearing. If the temperature is correct,
add a few more drops of carbonate, and continue adding a few drops at a
time until the image does make its appearance.
399. Image Flashing Up at Once. — This would happen if the plate
was extremely over-exposed, and too much carbonate of soda had been
used to begin with, and possibly the developer too warm. If the plate
acts this way place it at once in a restraining bath, either old developer,
or add five drops of bromide to your special developer. This should
not occur, even if plate was considerably over-timed, provided you have
not used too much carbonate of soda. Long exposure requires less car-
bonate, and the shorter exposure more.
400. Obtaining Proper Strength. — If the plate has been sufficiently
exposed and you have added your carbonate of soda too rapidly, or
using too strong a solution you will produce flatness, and no strength.
On the other hand, if you do not add carbonate of soda often enough,
162 Library of Practical Photography.
the plate will remain weak, and develop extremely slow. After you
have produced all the detail in the drapery, and find that the highlights
hold back, and do not build up strong enough, place the plate for a few
seconds in a normal developer. In this way you will obtain the neces-
sary strength to produce highlights.
401. Plate Fogging. — A plate extremely over-exposed, with too
much carbonate of soda used, is apt to fog. As in this method the de-
velopment is extremely slow, it is advisable to keep the plate as far
away from the ruby light as possible. It is also a good plan to use
a cover over your developing tray. Air coming in contact with the de-
veloper will cause oxidation, which is apt to produce a scum and foggy
effect on the plate.
402. Plate very Thin After Fixing. — Possibly under-developed, or
too much carbonate of soda has been used. It is generally caused by
under-development. You should bear in mind, however, that these
plates are expected to appear somewhat thin, although you will find
that they will have more printing strength than their appearance would
lead you to believe.
403. No Detail in Shadows. — This is generally caused by under-
exposure, and then using too little carbonate.
404. Highlights too Strong, Losing All Detail. — This will occur if
the plate has not been sufficiently exposed, and too much carbonate is
used. It will also occur if the plate has been sufficiently exposed, but
the carbonate added in too great quantities and too frequently during
development. Usually not more than one-half ounce all told of carbon-
ate is ample to fully develop any plate.
405. Color of Plate too Gray. — The color of the plate is, of course,
governed entirely with your sulphite. On account of the small quan-
tity of carbonate being used it may at times be necessary to reduce the
strength of the sulphite ; otherwise the plates are apt to be too gray.
It is advisable to have a tinge of yellow in the negative. The weaker
the sulphite the more color you will have, and vice versa.
406. Plates Frilling. — As this is slow development care should be
taken that the developer is not too warm, and that the hands are not
placed in the developing solution too often, as every time you place
your hands in the developer you are increasing the temperature, as the
hands are naturally warm. Always use fresh strong hypo bath, and
have it cold. If you find that the plates still show frilling treat them to a
weak solution of alum immediately after fixing, always being careful to
rinse the plates in water before placing in the alum. They must then be
thoroughly washed before you set them up to dry.
407. How to Treat a Plate which Has Not Been Sufficiently Ex-
posed, so as Not to Lose the Negative Entirely. — When you find that
the exposure is too short for this development simply rinse your plate
in water and transfer to a normal developer. Oftentimes you will find
White Drapery Portrait Negatives. 163
it necessary to treat the plate as ordinary under-exposed by soaking in
water, and then finishing in a diluted developer.
408. How to Treat a Plate which Has Been Sufficiently Exposed,
but too Much Carbonate Had Been Added to the Developer. — Immedi-
ately remove your plate from the developer, rinse it for a few moments,
and then place in a restraining bath, or add about ten drops of ten per
cent, solution of bromide to your special developer; in other words,
treat as over-exposed — developing to an excess and reducing afterwards.
409. Plates Developing in Streaks, Uneven Development. — This
is generally caused by allowing the plate to stand too long without agi-
tating the developer. While it is not advisable to rock the tray too
much, you should rock it occasionally.
410. Transparent and Semi-Transparent Spots in the Negative. —
These are generally caused by air-bells gathering on the plate when the
plate is first placed in the developer. A very good plan is to swab the
surface of the negative with a piece of absorbent cotton which is thor-
oughly saturated with developer. This will remove all air-bells, and
will also remove any particles of dirt that might be in the developer,
and in the tray.
411. Judging the Proper Amount of Carbonate to Use when First
Starting to Develop. — Bear in mind that you can hardly use too little.
It is better to start with too little carbonate than too much. You can
always add the carbonate solution, but you cannot very well change it if
you have added too great a quantity. Ten to twelve drops is usually
sufficient to start with. If the image does not appear inside of two
minutes add three to five drops more, and do not add any more for at
least another minute, for when the developer once has sufficient carbon-
ate it will develop quite rapidly.
412. Plate Appearing to Develop Properly but the Highest Lights
Not Gaining Sufficient Strength. — This would signify that you used too
much carbonate. Add a very small quantity of the pyro stock solution,
also a few drops of bromide ; at times a few drops is all that is necessary
to produce the desired results.
CHAPTER XV.
HYDROQUINONE AND EIKONOGEN — NON-
STAINING AND NON-POISONOUS
DEVELOPER.
413. Although there is no developing agent that can equal
pyro for the best general results, yet some object to its use
owing to it staining the fingers when proper care is not exer-
cised.
414. While either, metol or hydroquinone make a good de-
veloping agent, yet metol to some users is poisonous, and
therefore, undesirable; consequently, the best developer that
will not stain the fingers, and is not poisonous, is hydroqui-
none and eikonogen.
415. This developer can be altered to produce most any
desired results ; while it does not produce the printing quality
in the negative that pyro does, yet it serves as the nearest
developing agent to pyro that is practical for all developing
purposes, with the least objection.
416. This developer can be used repeatedly for several
batches of plates, but for the best results should be made up
fresh for each day's work. It is desirable to save the devel-
oper of one day's use for the developing of plates you believe
to be over-exposed slightly, and after starting the plate in
normal developer, and you found it to be over-exposed, trans-
fer to the tray containing the old developer, and allow it to
remain in this solution until it takes on sufficient strength,
then transfer to the normal developer for final developing.
You will find that plates developed with this developer pre-
pared exactly according to formula will have a very fine grain,
166
166 Library of Practical Photography.
and the color will be very near that of a pyro developed neg-
ative. The shadows and highlights will be clear and with
good detail.
Formula for hydroquinone and eikonogen developer : —
Stock Solution, No. i.
Hydroquinone 40 grains
Eikonogen 120 grains
Sulphite of Soda (Anhydrous) i ounce
Citric Acid 20 grains
Water 10 ounces
Stock Solution, No. 2.
Bromide of Potassium 5 grains
Carbonate of Soda (Anhydrous) 60 grains
Caustic Soda (Sodium Hydrate) 30 grains
Water 10 ounces
(If crystals sulphite or carbonate are used, use double the quantity.)
Mix all the chemicals in the order given.
For use take one ounce of each of the stock solutions, and
add one ounce of water. This will then give you three ounces
of developer, sufficient for the developing of a 4 x 5 plate. If
the factorial method is employed for this combination devel-
oper the factor would be eight.
417. Acid-Fixing Bath. — The plain fixing bath has
the disadvantage of becoming dark and discolored when or-
ganic developers are used, and, consequently, it is liable to
stain the plate. This is overcome by using the acid-fixing
bath according to the following formula : —
Water 80 ounces
Hypo 4 ounces
Dissolve and then add citric acid one and one-fourth
ounces. After this has been dissolved add hypo sixteen
ounces. When the ingredients are all dissolved the bath is
ready for use, and plates should be fixed at least twenty
minutes.
H})droqumone and Eikonogen. 167
418. Nature and Action of Chemicals Used. — Hydro-
QjuiNONK, — The action in developing of hydroquinone is much
slower than that of eikonogen, but it is more constant, lasts a
great deal longer and produces more contrast. When used
alone the negatives produced are apt to be too contrasty.
While it gives a fine black velvety color, it does not give the
blue-black as the eikonogen. It being slow in action, it allows
for all color latitude in exposure, and is, consequently, easily
controlled. Hydroquinone comes in the form of yellow,
nearly white, needle-like prisms, and is very soluble in water,
Eikonogen. — The action of eikonogen in the developer is
similar to hydroquinone. It is, however, much more energetic
in developing than hydroquinone. It inclines to produce soft-
ness, and an abundance of detail. The action is so rapid when
used alone, especially in the case of over-exposure, that
combined with its quality in producing softness it is apt to
cause fog. It is for this reason that the hydroquinone, which
is much slower as a developing agent and contrast pro-
ducer, is added. The color produced with eikonogen is blue-
black negatives, with a very fine grain. It is non-poison-
ous, and does not stain the fingers. Eikonogen comes in
small white-gray crystals, and dissolves slowly. From the
description of these two developing agents you will readily
see why they have been combined — one producing too much
softness, and the other too much contrast when used alone.
Eikonogen alone would also develop too rapidly, and would
be apt to fog the negative ; hydroquinone alone would develop
too slowly, and produce too much contrast. Consequently,
the two combined in the proportion given in the formula sup-
plies a well-balanced developer.
419. Carbonate and Sulphite of Soda. — The sulphite
and carbonate of soda act exactly as they do in the pyro de-
veloper, the carbonate opens the pores, and the sulphite con-
trols the color of the negative.
420. Caustic Soda (Sodium Hydrate.) — Is a white,
transparent, brittle substance very soluble in water, and
strongly alkaline, used in the developer as an additional ac-
celerator.
168 Library) of Practical Photography.
421. Bromide of Potassium. — Bromide of potassium is
a white crystal used as a restraining agent. It restrains the
development and holds the shadows clear throughout the de-
veloping.
422. Altering Developer. — While this developer can be
altered to produce any desired effect, yet it is advisable
to develop for some time with the regular formula as given
until you become thoroughly familiar with the results to
be produced. If after having some experience you find
the developer working a little contrasty, you can produce
more softness by reducing the amount of hydroquinone. For
instance, instead of using forty grains of hydroquinone use
thirty-five, and if this does not give you the desired softness,
then increase the eikonogen to 130 grains. Care must be ex-
ercised that you do not use too much of the eikonogen, as it is
apt to produce fog. In case of too much softness with the
regular formula, increase the hydroquinone to forty-five grains,
and if still too soft and a lack of contrast, increase to fifty
grains. Just remember that hydroquinone will give you
contrast, and eikonogen softness, so you can alter your
developer to produce whatever results you desire. Both
chemicals being powerful, the alteration should be made
with but a few additional grains at a time, and a small
quantity of stock solution should be prepared to experi-
ment with. When you once obtain a well-balanced de-
veloper, do not alter it, for too much altering usually
causes confusion, and leads to many failures. The formula
as given will give you a well-balanced developer for all ordi-
nary purposes, and unless the results are very much out of
the way, it is not advisable to alter the proportion, but use
the developer according to formula, and in case of too much
harshness, indicating under-exposure, manipulate the devel-
oper with Special Stock Solution No. 3, made as follows: —
423-
Water 10 ounces
Eikonogen 120 grains
This solution must be kept in a bottle and the bottle well
wrapped and with good stopper. In case of too much con-
i
Hydroquinone and Eikonogen. 169
trast, harshness, remove the plate from the normal bath, and
add from ten to twenty drops of No. 3. Mix well, and return
the plate to this developer, and conclude the developing in
this bath, Eikonogen is a detail-producing chemical as well
as developing agent, and by increasing the amount of this
chemical within the limit to avoid fog, usually an under-timed
plate would be very much improved, and a good negative will
result.
424. If you find the plate you are developing is over-
exposed treat according to instructions on developing over-
exposures, and either add a few drops of ten per cent, solution
of bromide to every ounce of developer you use, or transfer
to old developer, which of course contains bromide liberated
from the plates which were previously developed in this de-
veloper. If extremely over-exposed, soak in the bromide so-
lution before developing. Follow instructions given in de-
veloping over-exposures with pyro developer.
425. Incases of extreme under-exposure after the plate
has started to develop, and the image appears contrasty and
weak in the shadows, place the plate in a tray of fresh water.
In the meantime add to the bath one ounce of No. 2, two
ounces of water, and a few drops of bromide. The bromide
will prevent the fog and give the eikonogen and accelerators
a chance to act on the shadows. Complete the developing
in this bath. By means of Special Stock Solution No. 3,
and the bromide solution you have absolute control of plates
under all conditions, and by working carefully and using
judgment any desired result can be obtained. All stock solu-
tions must be kept in tightly corked bottles, glass stoppers
preferred. Have the bottles brown or yellow. If plain glass
bottles are used, wrap with dark paper, and place them in a
dark, cool place in the dark room.
CHAPTER XVI.
METOL-HYDROQUINONE AND METOL-ADUROL
COMBINED DEVELOPER FOR NEGATIVES
AND LANTERN SLIDES.
426. The various developers mostly show in their char-
acter considerable variation. Each has its special merit,
which makes it suitable for a particular work. In order,
therefore, to combine developers of these special properties,
the various developers can be applied in a mixed form, and a
great deal of use is made of such processes.
427. For these combinations metol and hydroquinone, and
metol and adurol, are those which deserve the greatest atten-
tion, and have, consequently, found the most use. These
combinations are distinguished from all others in a remarkable
manner, as the properties, or the components, do not simply
combine, but they also increase considerably in efficacy. For
instance, metol-hydroquinone works with greater energy than
metol alone, and gives more density than hydroquinone alone.
The reason for this is that when combining metol and hydro-
quinone it is not simply a mixture, but at the same time in the
alkaline solutions, an actual chemical combination takes place,
which again possesses other properties than the components.
The fact that metol-hydroquinone develops more quickly
than metol and gives more density than hydroquinone, makes
it preferable in some instances for use in the studio and for
instantaneous photography, as it permits in both cases of
shorter exposure, and works more rapidly.
428. Metol-hydroquinone, in its class, is the most popular
developer of the day, and forms the main substance of nearly
II— 10 171
172 Library) of Practical Photography.
all the ready solutions which are on the market. It is
the most popular developer for developing papers, and for ob-
taining clean black tones on bromide paper it is unsurpassed.
For negatives, especially lantern plates, it is probably the
most used developer, outside of pyro.
429. Metol-Hydroquinone Developer. — Being a very
rapid developer, will completely develop a plate, or film, in
from two to six minutes. It is recommended for lantern
slides, and film developing in particular, but serves as a good
plate developer as well. The color of the negative is inclined
towards a blue-gray, and, therefore, plates other than lantefn
plates developed with this bath should be carried a trifle
further in development than if developed with pyro, for the
pyro gives a brown colored negative which produces vigor-
ous prints, even from a thin negative. While the metol giv-
ing a blue-gray negative, if developed thin, will produce flat
prints, where if carried a little further in the developing,
better prints will result. For lantern slides the blue-gray
tone is preferred, and therefore this combination serves as a
good developer. Any result may be obtained by manipu-
lating the developer. Certain rules must be observed, how-
ever. Deep black tones can only be obtained with short ex-
posures, and strong developers ( concentrated solution,
and little bromide ) ; warm tones going into brown can
be obtained with longer exposure and retarded develop-
ment ( diluted solutions, little alkali and much bromide of
potash). The best plan is to follow the instructions given
with each kind of lantern plates. It must be observed that
with a long duration of development of the lantern plates the
plate will become colored, and it is, therefore, important that
you develop quickly; two to three minutes is best. Under-
exposed images are best discarded, generally speaking, espe-
cially for obtaining black tones.
430. Metol, to some users, is poisonous and therefore ob-
jectionable. Many however are using metol developer with-
out any ill effects whatever, and for those who can use it
they will find the formula stated herein to give very good re-
sults : —
Developer for Lantern Slides. 173
' Metol-Hydroqjljinone Formula.
Water 50 ounces
Metol H ounce
Hydroquinone i ounce
Sulphite of Soda (Anhydrous) 3% ounces
Carbonate of Soda (Anhydrous) 53^ ounces
Dissolve the chemicals in the order indicated in the for-
mula, and for use prepare as follows:
To every ounce of this concentrated Stock Solution add
eight ounces of water, making nine ounces of solution. One-
half of this amount is sufficient for the developing of a 4 x 5
plate.
431. If the factorial method for developing is employed
with this combination formula, you will find ten as the factor,
and it will completely develop plates in six minutes, and for
tank development, by substituting ten ounces of water to
every one ounce of concentrated stock solution, you will
have an eight minute developer. Slow development with
this metol formula is very apt to produce fog ; therefore the
best results are obtained when development is completed
within eight to ten minutes.
432. Metol-hydroquinone keeps better, and consequently is
more economical than other developers. The solutions can be
used until entirely exhausted. The following are a few addi-
tional formulas that will give good results, and are particu-
larly good for lantern plates : —
No. I. A T'wo-Solution Metol-Hydroquinone Developer.
Solution A.
Water 35 ounces
Metol 115 grains
Hydroquinone 115 grains
Sulphite of Soda (Crystals) 5^ ounces
If Anhydrous Sulphite is used, use 3 ounces.
Solution B.
Water 35 ounces
Carbonate of Potash 3)^ ounces
174 Library of Practical Photography.
Note. — Carbonate of Soda may be substituted for Potash, as fol-
lows : —
Carbonate Soda (Anhydrous) 4 ounces
Or, Carbonate Soda (Crystals) 8 ounces
433. The metol and hydroquinone must be dissolved before
the sulphite of sodium is added. For use take one part A,
one part ^, one part water, and add, as required, from five to
fifteen drops bromide of potassium. It is also permissible to
originally add to this Solution jB a few drops of bromide of
potassium, as it will do no harm. The temperature for devel-
opment should not exceed sixty-eight degrees Fahr. Dura-
tion of development from three to four minutes. The previ-
ously used developer can be employed repeatedly.
No. 2. Metol-Hydroquinone One-Solution Developer.
Water 35 ounces
Metol 115 grains
Hydroquinone 115 grains
Sulphite of Soda (Crystals) 5^^ ounces
Carbonate of Potassium 5^^ ounces
Bromide of Potassium 8 grains
Note. — If Anhydrous Sulphite is used in place of Crystals, use
three ounces.
Carbonate of Soda may be substituted for Potash, as follows :
Carbonate of Soda (Anhydrous) 6 ounces
Carbonate of Soda (Crystals) 12 ounces
434. The metol and hydroquinone must be dissolved before
the sulphite of soda is added. For use take one part solution
to three parts of water. The temperature for development
should not exceed sixty-eight degrees Fahr. The image,
w^hen applying this developer, will appear almost instantane-
ously, and development is completed in about three minutes.
The used developer can be employed repeatedly.
Metol- Adurol.
435. With advantage sometimes adurol takes the place of
hydroquinone in combination with metol, and it has the advan-
Developer for Lantern Slides. 175
tage of working more clearly, and dissolving more easily,
while its keeping properties are still greater. Concentrated
solutions can therefore be made which are especially adapted
for amateurs. Metol-adurol works in a similar manner to
metol-hydroquinone, and is very economical. It is equally as
good a developer for paper as for plates, and is especially
good for lantern plates. Metol-adurol in the combination
given, in spite of its rapidity, can be easily controlled with
bromide of potassium, and especially the used developer can
be applied as advantageously for over-exposures. Metol-adurol
is a good developer, which above all others best combines the
advantages of a rapid developer with variation, and may
therefore be recommended as a universal developer for studio
work for those who do not care to use pyro.
Formula No. i. Metol-Adurol T-wo- Solution Developer.
A Water 35 ounces
Metol 75 grains
Adurol 150 grains
Sulphite of Sodium (Crystals) 3)^ ounces
Or, if Anhydrous Sulphite is used 2 ounces
B Water 35 ounces
Carbonate of Potash 3)^ ounces
Note. — If Carbonate of Soda is used in place of Potash, take
Carbonate of Soda (Anhydrous) 4 ounces
Or, Carbonate of Soda (Crystals) 8 ounces
436. The metol and adurol must be dissolved before the
sulphite is added. For use prepare as follows : For rapid
development take one part yl, one part B. Duration of de-
velopment two to three minutes. For slow development take
one part A^ one part B^ one part of water, and add from five
to ten drops bromide of potassium. Duration of development
from three to four minutes. The temperature of the devel-
oper should not exceed sixty-eight degrees Fahr. Previously
used developer can be repeatedly employed.
176 Library of Practical Photography.
Formula No. 2. Metol-Adurol One- Solution Developer.
Water 35 ounces.
Metol 150 grains.
Adurol 2 ounces.
Sulphite of Sodium ( Crystals ) 10)^ ounces.
Or, if Anhydrous Sulphite is used, use 6 ounces.
Carbonate of Potassium 8^ ounces.
Bromide of Potassium 20 grains.
Note. — If Carbonate of Soda is used in place of Potash, take
Carbonate of Soda (Anhydrous) 9 ounces.
Carbonate of Soda ( Crystals) 18 ounces.
437. The metol and adurol must be dissolved before the
sulphite is added. For use prepare as follows : For rapid de-
velopment take one part solution to five parts water. Du-
ration of development from two to three minutes. For slow
development take one part solution, and fifteen parts water.
Duration of development about five minutes.
438. Metol-adurol developer, on account of its small con-
tents of metol and larger contents of adurol, is very easily
variable. A few drops of bromide of potassium suffices to
retard development. Where you have a plate of strong over-
exposure take a previously used developer with the further
addition of bromide of potassium. A still better plan is to
take less potash for the developer, in which case the influence
of the bromide of potassium is strong. Take, for instance,
for formula No. i, forty parts A to ten parts ^, fifty
parts water, five parts bromide of potassium. For Formula
No. 2, fifteen parts solution, eighty parts water, five parts bro-
mide of potassium. Where over-exposure has not been so great
the used developer suffices for development. For unknown
exposure always commence with the used developer, and cor-
rect according to requirements.
For fixing use the acid-fixing bath, prepared as follows : —
Water 80 ounces.
Hypo 4 ounces.
Dissolve and then add, citric acid i^ ounces.
After this is dissolved add, hypo 16 ounces.
'D
CHAPTER XVII.
AMMONIA DEVELOPING.
439. Developing Instantaneous Exposures with Am-
monia Developer. — The ammonia developer is not recom-
mended for general work, nor even for special work, but is
included in this instruction for the benefit of the few who
wish to go to the extremes with experiments, for any reason-
able and positive result can be obtained from any of the pre-
vious formulae given. There are extreme cases, however,
where ammonia developer is an advantage, and to cover these
cases is the object of this instruction. The amount of ammo-
nia to be used in this developer depends to a large extent upon
the exposure. Unless the proportions of the developer are
prepared according to the exposure given the plate there is
danger of fog. For extremely under-timed plates some like
the ammonia developer, as more detail can be coaxed out with
the ammonia as an accelerator than any of the sodas, and this
formula is, therefore, supplied for these extreme cases only.
We do not advise using the ammonia developing formula
given in this instruction for regular exposures, or snap shot
work made with the ordinary shutter, but for extremely short
exposure, or those made with focal-plane or similar extremely
rapid shutter giving less than -5-^ part of a second exposure
in bright sunlight, and not more than -j-stt part of a second
in dull light. This class of instruments are usually used on
moving objects, such as running or jumping horses, cattle,
179
180 Library) of Practical Photography.
birds and trains, or cars in motion, athletic sports, or any
rapid moving object requiring most rapid exposure, and a
quicker exposure than can be given with the ordinary shutter,
for all such objects must be photographed without any blur,
and to do so the shutter must move across the sensitized plate
more quickly than the object being photographed. There are
times also in slightly cloudy weather when one must make
exposures of moving objects which could not be obtained at
any other time. All such exposures if developed in the ordi-
nary way would be considered under-timed, and even if they
were treated as such ( with the ordinary developing ) , if the
exposure should be extremely short, one would not obtain as
much detail and solidity as it is possible to obtain with the
ammonia developer, providing the developer is properly bal-
anced.
440. The alkalies used in ordinary developing are usually
some soda of a strong, harsh nature. This strong alkali, if
used on extreme under-timed plates, even with a very much
^ diluted developer, has a tendency to choke and clog the high-
est lights, and the shadows being so very meagerly exposed
the soda does not have the same action as it does on the more
^ fully exposed parts. While the ammonia acts just the reverse,
it is of a more penetrating nature, and has a tendency to at-
tack the least exposed parts the most ; therefore, the shadows
being the the least exposed it attacks them first. In the de-
veloping of this class of exposure, we must assume that these
plates are of short exposure, or extremely under-exposed,
and while in previous instruction the treatment for the devel-
opment of under-exposed plates has been pretty thoroughly
covered, yet the former training dealt with general ex-
posure of portraiture, interior, landscape and architectural
photography. The formula in this instruction, however, is
intended purely for the plates that are very much under-ex-
posed, and for extremely rapid instantaneous photography.
In such pictures the main object is to show the subject in
motion, and to get the image perfectly sharp the exposure
must necessarily be extremely short, and there must be enough
detail and strength in the negative to supply the proper print-
Ammonia Developing. 181
ing quality. In previous instruction on developing you have
been advised as to the proper color of the negative, which
should be a slight tinge of brown. In this case of extreme
under-exposure, however, you will find that many times a
very thin negative with a yellow color will produce prints of
much finer quality than extremely thin plates of a brown
color, such as is required for ordinary portraiture, architec-
tural or landscape views, where the full exposure was given ; for
with the extremely thin plate the color of the plate slows the
printing, and thereby adds strength to the shadows, thus sup-
plying more brilliant prints.
441. In the early days of the dry plate, ammopia was uni-
versally used as an alkali in place of carbonate of spda, which
is generally used to-day. The principal reason for 'discarding
ammonia was, that the negatives generally obtained with this
ammonia alkali were extremely yellow, and the latitude in
development was limited, and if plates were carried a trifle too
far in the developer the prints produced from them would be
contrasty, with strong highlights, and hard shadows. Ammo-
nia developer has its advantages, especially in the developing
of instantaneous exposures, because its accelerator properties
are much stronger, rendering the solution very alkaline, yet
not harsh, and enhancing its deoxidizing power. It also
possesses the advantage over all other alkalies of giving greater
vigor; thus its action is quicker, and with the under-exposed
plate very easily controlled, while for normal or full-timed ex-
posure ammonia accelerator would be more difficult to control,
and better results can be obtained with other accelerators.
442. The following formula will produce most excellent
results, and can be altered, or the developer manipulated dur-
ing development to suit most any rapid exposure: —
Formula.
Water lo ounces
Pyro (dry) 20 grains
Bromide of Potassium 10 grains
Ammonia ( specific gravity 800 ) 20 drops
It is necessary that the ammonia be concentrated ammonia ,
the ordinary commercial ammonia is too weak, and should
182 Library of Practical Photography.
not be used. If, however, the former cannot be obtained, and
you are compelled to use the weaker ammonia, then you will
need to use a larger quantity of it — sufficient to make up for
the difference in strength.
443. As the ammonia evaporates rapidly the developer
should not be made up until you are ready to use it. The
proportions given in the formula above are just right for nor-
mal developer, and should be used without diluting unless the
plate is extremely under-exposed, then you should double the
quantity of water used, making twenty ounces in all.
444. With the ammonia developer on an under-exposed
plate the image will appear a little quicker than with soda
accelerators, but after the image is plainly visible the devel-
oping will be extremely slow, as the ammonia evaporates
very rapidly and you will, therefore, from time to time need
to add a few drops of ammonia, replenishing that which has
evaporated. The very fact that the developer acts slowly
will prevent the highlights from piling up and growing too
strong before there is sufficient detail in the shadows, which
would be the case if carbonate of soda were used.
445. The bromide of potassium provided for in the formula
in excessive quantities, no doubt will seem strange to you, for
in your past instruction you were told to use bromide of potas-
sium as a restrainer for plates which were over-exposed. In
this case, however, the bromide is used in excessive quantities
to protect the plate from fog, as the ammonia is very apt to
fog the shadows unless restrained with bromide. As am-
monia has a tendency to attack the shadows, or the least ex-
posed parts first, the bromide does not have the effect of re-
straining them, but merely holds them clear of fog, thus en-
abling the developing agent to act more freely.
446. Developing of Plates. — Having carefully pre-
pared your developer, according to the formula, place the ex-
posed plate in the tray, and flow with a sufficient quantity
solution to thoroughly cover it with one sweep. Use plenty
of developer. Avoid rocking the tray more than is absolutely
necessary. Carefully' watch the plate, and within a reasona-
ble time the image should appear. If after the image ap^
Ammonia Developing. 183
pears it continues to grow right along, you will know the
exposure is all right for the developer you are using. If
within a few minutes after the image appears the action of
the developer is slow and lagging, you will know that the
plate was extremely under-exposed. You should then add
enough water to make double the quantity of solution, and
cover the tray, excluding all light, and continue the develop-
ing, and if the developing appears still to lag, every five or
ten minutes add two drops of ammonia for every ounce of de-
veloper that you are using. This additional ammonia is to
take the place of the ammonia which has naturally evaporated.
When you have obtained sufficient density in the highlights,
then your plate is sufficiently developed, and you should wash
and fix the plate in the usual way. The temperature of the
developer should be between sixty-five and seventy degrees.
The colder the developer the slower the action. If the de-
veloper is too warm the action would be rapid, and the plate
would have a tendency to soften, frill and fog in the shadows.
If you find after fixing the negative it is extremely yellow, you
can remove this color, or part of it at least, by clearing with
the alum clearing solution according to the formula given in
lesson on Reducing. Before clearing, however, unless the
shadows appear with good strength, it is advisable to dry the
negative, and make a proof before removing the color, as
oftentimes the yellow color in a negative is the salvation of
an extremely under-exposed plate with weak shadows, for it
slows the printing and permits the light to penetrate deeper
into the shadows, resulting in a much more solid print.
447. Caution. — Do not add more ammonia to the devel-
oper until you require it ; that is, when the developing appears
to have ceased, and the plate is very thin and lacks strength,
then add more ammonia, and add it cautiously. Remove the
plate from the developer while adding the ammonia, and rock
the tray to thoroughly mix the ammonia with the developer,
then return the plate to the developer. Too much ammonia
will cause a fog, so work cautiously, and after a few experi-
ments you will be able to judge to the drop how much am-
monia to add, and by the proper care and pains you can pro-
184 Library of Practical Photography.
duce negatives with fair detail in the deepest shadows from
plates that if developed with soda developer would render al-
most clear glass. This formula and method of development is
only recommended to those who have carefully worked all
the previous developers and formulae given in this volume,
for as each different formula is given for a particular purpose
it is taken for granted that the reader has had the benefit and
experience of all the previous instructions before attempting to
apply[this method, and for the large majority of exposures any
of the former formulae are preferable. Even for instantaneous
work usually the metol-hydro developer will, if properly ma-
nipulated, render all detail that the given exposure will supply.
But those who enjoy experimenting will find some interesting
results can be obtained with ammonia developer ; yet it is not
always reliable, and therefore is not recommended. Proof
prints should be made from each experiment, with complete
data noted on the back. This data will aid you in your future
experiments, and therefore proofs and all data should be care-
fully filed.
CHAPTER XVIII.
FACTORIAL DEVELOPMENT.
448. By factorial development is meant the technical
method of development in which the process of developing
is regulated solely by mathematical figuring, when certain
conditions exist. It is the object of this instruction to
thoroughly consider these conditions, and to make the subject
of factorial development so simple that even a person who
has had little or no experience in negative making can take
the exposed plate and having received the instructions neces-
sary for proceeding to develop by the factorial method, be
able to produce an excellently developed negative.
449. The Factor. — The factor is the agent or the means
by which is found the required length of time that the ex-
posed plate must remain in a developing solution composed of
a certain developing agent. Originally the factor is found
by developing a normally exposed plate in the usual manner,
regardless of the nature of developing agent, and in this case,
of course, it is necessary, in order to obtain an accurate fac-
tor, that the person who develops the plate has a perfect
knowledge of the requirements of an ideal negative.
450. Obtaining the Factor.— In order to obtain the
factor for developing, after carefully preparing the bath ac-
cording to the formula, see that the temperature is sixty-five
degrees Fahr. ; then place a normally exposed plate in the
bath, and observe the time required for the strongest high-
lights of the image to appear fully with the general outlines,
also faintly visible. The rapidity of this appearance indicates
the speed of the developer. The relation between this time of
appearance and the total time to develop is the factor, and
185
186 Library) of Practical Photography.
all future baths made according to the same formula, and of
the same temperature, will completely develop plates in the
same time. To make this more clear, before placing the
normally exposed plate in the normal developer note the time
by your watch or clock, then place your plate in the devel-
oper, watch the action of the solution upon the plate, and
as soon as the highlights appear fully and a general outline is
slightly visible, again note the time, and see exactly how
many seconds were required for development to this stage ;
or, in other words, how many seconds the plate was in the
developer. Make a note of this number of seconds, and of
course the negative continues developing, and when the
plate is completely developed again note the total number of
seconds (or minutes reduced to seconds), required for devel-
opment from the placing of the plate in the developer until it
is completely developed. Now divide the total number of
seconds by the number of seconds recorded for the first ap-
pearance of the highlights, and this result is your factor.
451. When the factor is once found by the method above
described, that factor will always hold good in case of a de-
veloping solution mixed according to the particular formula
used in the test. If another developing agent is employed it is
necessary to make another test, and find a factor for that par-
ticular developer. Where we have a combination of different
developing agents, such as metol-hydroquinone, metol-pyro,
etc., separate factors must be obtained for each agent, and the
proportionate amount of each used in the formula must be con-
sidered in computing the factor for the combination formula.
As we supply the Watkins' table of factors of practically all
the developing agents, it will not be necessary that you make
this test unless you have a particular formula which does not
come under the accompanying table. Should that be the case,
you will be able to obtain a factor by following the direc-
tions given above.
452. Temperature. — The temperature ot the developer
is of the utmost importance, as high temperature hastens the
action, and lower temperature retards the action. Sixty-five
degrees Fahr. should be a normal temperature, and all devel-
Factorial Development. 187
oping solutions, in order to be accurate, should be of the same
temperature. A few degrees one way or the other, however,
will do little or no harm, but one should strive to retain the
normal temperature.
453. One of the chief difficulties in obtaining a factor lies
in the accurate judgment by different persons of the time of
appearance of the image, and not only is this true of different
persons, but the same person at different times when develop-
ing exposures under varying conditions, for instance plates
with strong highlights and plates with soft highlights as in
misty scenes, etc., may estimate the appearance of the image
as being shorter in some cases and longer in others. The only
real accurate way to obtain the factor for a certain developer
which you wish to employ, would be to make an exposure on
some object with medium highlights, and develop it, and ob-
tain your factor from this plate ; then all other plates under
any and all conditions can be developed by the same factor.
454. It is argued that with a long factor the multiplication
of any error, engaging the exact time of appearance, will
greatly increase the total length of development, thus produc-
ing negatives of undue density, and probably incorrect grada-
tions, but the longer the factor the greater is the latitude, and
this makes up, to a certain extent, any variation in judging the
appearance of the image.
455. Developing Light. — It is essential that you always
hav« a liberal allowance of light in the dark room (of course
non-actinic) , for this is of the highest importance while watch-
ing for the first appearance of the image. If average care is
used the slight variation of judging the first appearance of the
image is of comparatively small importance and, in fact, is
much less likely to cause variations in the results than with
the old system of judging density by inspection. Some in-
dividuals are occasionally quicker or slower in noting the ap-
pearance of the highlights than others, but as a rule this
variation is uniform, and may be allowed for by adopting a
proportionately higher or lower factor for the same developer.
456. When you have a given factor for a certain devel-
oper, you may proceed to pour the developer on your ex-
188 Library of Practical Photography.
posed plate, keeping exact time required for the image to
appear, then multiply this time by your factor, and the result
will be the number of seconds required for the plate to remain
in the developer. If you wish to change this time to minutes,
simply divide your result by sixty (60).
457. Effect of Different Developing Agents. — Pyro
and amidol are different from all other developing agents,
when considering the factorial system. With all other devel-
oping agents the factor does not alter, to any great extent,
with strength or dilution, but with pyro or amidol the factor
varies with the strength in grains to the ounce in solution.
The use of bromide of potassium (or its omission), also alters
the factor greatly with pyro and other short factor developers,
such as hydroquinone, etc., while with the longer factor devel-
opers, such as metol, etc., the bromide has but very little ef-
fect. In pyro, and other short factor developers, the addition
of bromide in the proportion of one-fourth grain to each grain
of pyro will cut the factor in half.
458. Variations in the amount of alkali (carbonate of soda
or potash) in the developer, does not alter the factor. As a
general rule the factor for different brands of plates or films,
which is right for one brand of plate, or film, is also correct
for another make of plate or film. It is true that some plates
develop much more quickly than others, but the time of ap-
pearance, which is the key to the total time required for de-
velopment, makes due allowance for this.
459. For orthochromatic, or any double coated plates, the
factorial method is almost indispensable, for they, above all
plates, are the most difficult to judge when they are com-
pletely developed, owing to their special coating ; but as the
factor is the same for all plates, all you need do is to note the
time of appearance of the highlights and multiply that time
by your factor, and the result is the time at which your plate
is completely developed.
460. Mr. Watkins, who is an authority on factorial devel-
opment, gives the following table of factors, which will prove
quite accurate and convenient : —
Factorial Developmerrl. 189
Table of Factors.
DEVELOPER FACTOR
Amidol (2 grains per ounce ) i8
Edinol 20
Eikonogen 9
Hydroquinone 5
Metol 30
Metol-Hydroquinone 14
Rodinol 40
Pyro Developers.
1 grain Pyro per ounce solution 18
2 grains Pyro per ounce solution 12
3 grains Pyro per ounce solution 10
4 grains Pyro per ounce solution 8
Pyro with Bromide.
^ gr. Bromide to i gr. Pyro per oz, solution .... 9
}^ gr. Bromide to 2 grs. Pyro per oz. solution .... 5
I gr. Bromide to 4 grs. Pyro per oz. solution .... 4
461. Developing with Different Factors Regulates
Speed of Developer. — The following formulae are given for
regular pyro developers prepared by the factorial system for
the developing of plates in four, ten, twenty and twenty-five
minutes. For the convenience of the reader we will apply
our regular universal pyro developer for use in this illustra-
tion : —
462. Stock Solution No. i.
Water 6 ounces
Sulphuric Acid C. P 1^ dram
Pyro •. . . . I ounce
Stock Solution No. 2.
Procure a 20-ounce bottle. Into this pour i ounce Stock Solu-
tion No. I, and add 16 ounces of water.
Stock Solution No. 3.
Sulphite of soda 40 hydrometer test, or by weight,
Sulphite of Soda (Anhydrous) i ounce
Water 13 ounces
II — II
190 Library of Practical Photography.
Stock Solution No. 4.
Carbonate of Soda ( Anhydrous), 20 hydrometer test ; or
if by weight,
Carbonate of Soda (Anhydrous) i ounce
Water 23 ounces
If Crystal Sodas are used, double the quantity in weight.
Use only the very best chemicals. We would recommend
Seeds, Cramer's or Mallinckrodt's anhydrous C. P.
463. Preparing the Stock Solution. — In order to avoid
early discoloration of the Pyro Stock Solution, it is advisable
to acidify the water before adding the pyro ; therefore, this
solution should be mixed up in the regular order: Into six
ounces of water pour one-half dram of sulphuric acid. This
acidifies the water. Then add to this one ounce of pyro. As
you have one ounce of pyro to six ounces of water, there is in
each ounce of solution one-sixth of an ounce of pyro. To re-
duce this to grains, divide 480 (the number of grains in an
ounce), by six, which gives a result of eighty. Therefore,
the grain strength of the pyro per ounce of the water will be
eighty ; or, in other words, you will have eighty grains of
pyro to each ounce of water,
464. In order to prepare this Pyro Stock Solution for use,
take one ounce of this Stock Solution, and dilute with six-
teen ounces of water. This makes your Solution No. 2, and
you have five grains of pyro to each ounce of this solution,
for in taking the above mentioned eighty grains which were
in each original ounce of Pyro Stock Solution, and adding
this to sixteen ounces of water, you will have about seventeen
ounces of solution to eighty grains of pyro, and when uni-
formly distributed throughout this bulk of water there will
be in each ounce -j^ of eighty, or 4.7 grains per ounce, or very
nearly five grains of pyro per ounce of solution.
465. Solution No. 3 is made up of sodium sulphite, testing
forty degrees by the hydrometer, while Solution No. 4 is com-
posed of sodium carbonate, testing twenty degrees by the hy-
drometer.
Factorial Development. 191
466. Mixing the Developer. — To mix the developer
take of Solution No. 2, four ounces, and as each ounce of this
solution contains five grains of pyro, the four ounces will con-
tain twenty grains. Add to this, two ounces of Solution No.
3, and two ounces of Solution No. 4, making a total develop-
ing solution of eight ounces. You now have eight ounces of
solution, and in this are twenty grains of pyro; therefore, the
number of grains of pyro per ounce of solution will be one-
eighth of twenty, or two and one-half grains per ounce.
Therefore, the grain strength of this developer is two and one-
half, and the factor for this developer is twelve.
467. Finding the Factor. — We found the factor in the
following manner : — A normally exposed plate was placed in
this developing solution (the temperature being sixty-five de-
grees Fahr, ) , and the image appeared in exactly twenty sec-
onds. The development was completed in exactly four min-
utes, or two hundred and forty seconds. Divide two hundred
and forty (the total length of time), by twenty (the time re-
quired for the image to appear), and this gives a result of
twelve. Thus twelve is the factor for this developer, and all
plates developed in this bath will develop in approximately
four minutes.
468. A Ten-Minute Developer. — If you desire a ten-
minute developer, take the above solution ( eight ounces ), and
add to it an equal bulk of water (eight ounces). You will
then have a total bulk of solution amounting to sixteen ounces,
in which is distributed twenty grains of pyro. Dividing the
twenty by sixteen gives one and one-fourth grains of pyro per
ounce of solution. With the developer at sixty-five degrees
Fahr., and a normally exposed negative, we found the image
to appear in twenty-five seconds, and it was fully developed
in six hundred seconds (ten minutes) ; therefore, six hundred
divided by twenty-five gives twenty-four, making the factor
for this particular solution twenty-four, and a plate developed
in a solution diluted as above will develop in approximately
ten minutes.
469. A Twenty-Minute Developer. — A twenty-minute
developer is secured by taking the above mentioned develop-
192 Library of Practical Photography^.
ing solution (eight ounces), and adding to the developer
double the quantity of water (sixteen ounces), making twenty-
four ounces of solution in which you have twenty grains of
pyro. Divide this twenty by twenty-four, and the result will
be five-sixths ; therefore, you have five-sixths of a grain of
pyro per ounce of solution. We found the image on a nor-
mally exposed plate to appear in this developer when the so-
lution was at sixty-five degrees Fahr., in thirty seconds, and
the development was completed in 1170 seconds (nineteen
and one-half minutes). The factor for this developer is, there-
fore, -^ of 1 1 70, or thirty-nine. Although the exact time of
development of this developer is nineteen and one-half min-
utes, the latitude for a developer of this dilution is so great
that no harm will be done in developing the plate for twenty
minutes ; and for tank development, where you do not desire to
look at the plate after it is placed in the developer, you will
find that leaving it in this solution from twenty to twenty-two
minutes will give you good development for negatives which
might vary in exposure, some being a little under-timed, some
normally exposed, and others over-exposed.
470. A Twenty-Five-Minute Developer. — If you take
the regular developing solution (eight ounces), and add
enough water to make the total bulk thirty-two ounces, or just
four times the bulk of the original solution, you will have five-
eighths of a grain of pyro to each ounce of solution, and we have
found that the factor for this developer is forty-eight. You
will, therefore, see that by doubling the bulk of solution of
the normal developer you will have just one-half as many
grains of pyro per ounce of water, and the factor is doubled;
while if you take four times the bulk of solution the grain
strength of each ounce is reduced one-fourth, while the factor
is four times as great. The average negative will develop in
the above pyro developer when the factor is forty-eight in ap-
proximately twenty-four minutes, but if you are developing
plates having varying exposures, and you are working with a
developing tank, uniform development will be secured by
leaving the plate in the developer for twenty-five minutes.
Factorial Development. 193
METOL-HYDROQUINONE FORMULA.
Stock Solution.
Water 24 ounces
Metol 15 grains
Sulphite of Soda (Anhydrous) i^ ounces
Hydroquinone i dram
Carbonate of Soda (Anhydrous) 5 drams
If Crystal Sodas are used double the quantity in weight.
Dissolve the chemicals in the order given,
471. Ascertaining Factor. — The factor of this form-
ula is ten. In this formula we have two developing agents —
metol and hydroquinone ; and we have sixty grains of hydro-
quinone, or four times as many grains of hydroquinone as we
have metol, the latter of which we have fifteen grains. These
developing agents, as formerly stated, having different factors,
we must ascertain the proportions used of each agent to the
developer, and our factor is regulated accordingly. The fac-
tor of hydroquinone we know from the table of factors is
" fi ve, " and for metol is ' ' thirty. ' '
472. Where we desire to take two different developing
agents and combine them into one developing solution, the
factor is approximately the average of the two constituents if
in equal parts. Thus, with hydroquinone " five" and metol
" thirty," if used in equal parts, the average will be " seven-
teen and one-half," but if the combined developer, as in this
formula, contains four parts hydroquinone to one part metol
(five parts in all), we must add the factors for all five parts
(the factor for each part being the original factor for that
particular developing agent), and divide by the total number
of parts; thus 5i±l±i±t?2— 10. Any combination of long factor
developers can be obtained in this way, but a combination de-
veloper containing pyro does not conform to this rule, and its
factor must be ascertained by actual trial.
473. A few facts should be remembered: The factor of
all developers, except pyro and amidol, depends upon the de-
veloping agent, and not upon the formula. The varying of
the quantity of water, or increase in alkali, or even the use of
194 Library of Practical Photography.
bromide, may alter the time of the appearance of the image,
but does not alter the effect of the long factor developing
agents, such as metol, etc. Temperature effects the time of
appearance, but does not modify the factor; however, with
pyro and amidol for short factor developers the factor varies
with the strength in grains to the ounce solution, but in all
other developers the factor does not alter with strength or
dilution.
474. Retaining Normal Temperature. — While under
ordinary conditions one can work with an average tempera-
ture of from sixty to seventy degrees Fahr., yet there are
times in very hot climates that the temperature is very high.
In such cases a quick developer is preferable, for the quicker
you can completely develop plates, fix and wash them, the
better it will be for the resulting negative. However, where
slow development is preferred one can, if they wish to go to
the little extra trouble, arrange their baths so as to hold them
at a certain temperature throughout the entire time of devel-
oping. First of all, the developing room should be kept cool,
and by providing a " water bath " into which you place your
developing tray, you can hold the developer to the tempera-
ture of the water.
475. If the temperature of the water is high, then the addi-
tion of a little ice in the ' ' water bath ' ' will reduce it to the
proper state. For example, take a tray or dish larger than
your developing tray and place water in this large tray, hav-
ing the temperature of the " water bath " lower than normal,
say 60 degrees Fahr,, and if the temperature of the room is 68
or 70 degrees Fahr. , place your tray containing the developer
in this " water bath," and after a few minutes you will find the
developing bath will become about normal, or 65 degrees. In
cold weather the same method may be employed. Instead of
using cold water, however, in the " water bath," sufficient
warm water can be used to raise the temperature as much
above that of your developer, or developing bath, as the tem-
perature of the room is below normal, thus equalizing the
temperature.
Study No. io
MARINE
S. I. Carpenter
Factorial Development. 197
The above suggestions are intended for extreme cases
only. Under ordinary conditions the extra "water bath" will
be unnecessary.
PRACTICE WORK.
476. In making your experiments with factorial develop-
ment, after carefully reading the instruction for obtaining
factors, etc., it is advisable for you to try out the formula
given. First try the pyro formula, and after providing your-
self with a few normally exposed plates, then proceed to pre-
pare your pyro developer exactly according to the formula
given. When you are ready to develop note the time by your
watch, and at once place the plate in the developer, and observe
the image as it appears. When the strongest highlights are
clear, and the general outline slightly visible at this stage,
take the time again and note the number of seconds it has re-
quired for the time of appearance, for this is the key to the
proper results. Multiply this time by your factor, which will
indicate the total time required for complete development.
By applying the factor given in this instruction, the only mis-
take you are likely to make is in judging the time of appear-
ance; and this you can become accurate in by experience and
intelligent experimenting only.
477. After your first experiment, dry the negatives,
and make proof prints from them, and note the results.
Note on the back of the proofs the date, first or second trial,
as the case may be. Note the time of appearance, the devel-
oper used, the factor employed, total time of development,
and any other data that can be used for future reference.
File these proofs in your letter file, under the title "factorial
development." After a few experiments with our regular
formula, change the formula and obtain a new factor, keeping
a record of the change. Make proofs from each resulting
negative, note formula on back of proofs, and the necessary
data, and file as usual. In this way you will have a prac-
tical record of all your experiments.
478. After experimenting with the pyro formula, next
198 Librar}) of Practical Photography.
take up the metol-hydroquinone developer, and make your ex-
periments, and prove all your results in like manner, making
careful note of each experiment, and number each proof so
that you can note your improvements from the first to the
last.
DIFFICULTIES — FACTORIAL DEVELOPMENT.
479. Judging the Time of Appearance. — This is perhaps the most
difficult in factorial development, and can only be successfully accom-
plished by practice. Watch carefully the negative as the image first
appears, as it will grow rapidly. The highlights must be watched care-
fully, and just as soon as the highlights are clearly visible, and the gen-
eral outline very slightly visible, that is the proper time of appearance,
and the number of seconds from the time the plate enters the developer
until that stage is reached, is the key to your accurate developing. Now,
if you allow the time of appearance to go too far — in other words, if
your image be developed too far before taking the time, the result would
be that your negative, when completely developed, would be strong; or,
if it were not carried far enough when taking the time of appearance,
as for instance, if you judge the time of appearance twenty seconds, and
it possibly should have been thirty seconds, this time multiplied by the
factor would shorten the necessary time for complete development, and
consequently the plate would be under-developed.
480. Obtaining the Factor. — If you study carefully the instruction
you should not have any difficulty in obtaining the factor. There are a
few things very necessary that must be remembered.
481. First. — The factors for pyro and amidol developers are gov-
erned by the strength in grains to the ounce solution. In other words,
to dilute a pyro bath changes the factor. Why.-" Because you at once
change the grain strength to the ounce solution.
482. Second. — The factor for all other developers depends entirely
upon the developing agent, and not upon the formula employed, and a
factor does not alter with strength or dilution, but the time of appearance
may be altered. For example, if the time of appearance with a normal me-
tol bath was fifteen seconds, and the factor was thirty, that would indicate
that in four hundred and fifty seconds the plate would be fully developed.
Suppose we dilute the metol with equal amount of water, the time of
appearance would be slower, perhaps twenty seconds. The factor is the
same, and it will require six hundred seconds to completely develop the
Factorial Development. 199
plate. In other words, diluting the developer only prolongs the devel-
opment, but does not change the factor in a metol, or long factor de-
veloper.
483. Controlling the Temperature. — It is not absolutely necessary
that the temperature be exactly sixty-five degrees. Anywhere from
sixty to seventy is safe, but beyond this limit you will experience trouble
unless you test each batch of plates for time of appearance, and that is
all the difference it makes in the accurate time of complete develop-
ment. It is advisable in cases of very radical changes of temperature,
and especially in very hot climates, that the time of appearance be taken
for each batch of plates, and as results are governed entirely by time of
appearance, you will experience no trouble, for while a bath at sixty-five
degrees Fahr. might develop to-day in six minutes, to-morrow if the
temperature of the developing room were sixty, the plate would develop
fully in eight minutes. All is governed entirely by time of appearance,
and you must work accordingly.
CHAPTER XIX.
TANK OR STAND DEVELOPING.
484. A great deal can be said in favor of tank develop-
ment, yet unless one has carefully followed the previous in-
struction given on developing by the ordinary way, so that
negative developing is thoroughly understood, it will not be
possible to produce the desired results, or fully appreciate the
value of this method of development.
485. Tank development is nothing more or less than
developing with a diluted solution, causing slow development
of the image, which latter is always commendable, for by
means of weak solutions resulting in slow development, all
classes of exposures may be developed in one and the same
tank, and at the same time. The mechanical part of tank
development is very simple. It consists in putting a num-
ber of plates into one tank, in which vessel they are held
in an upright position, and surrounded with a weak solution
of normal developer, at a certain temperature, which is
allowed to act for a certain length of time. At the expira-
tion of the required time for complete development the plates
are removed from the tank, and fixed in the usual way.
486. Latitude in Development. — There is a wonder-
ful latitude in the time of development with tank developer.
A plate may be developed in ten minutes or two hours, pro-
ducing practically the same results, and this is entirely gov-
erned by the strength of the developer employed, and the
temperature of the solution, which regulates the time for com-
plete development.
201
202 Library of Practical Photography.
487. To prepare a developer for tank development and a
bath that will develop plates in a certain number of minutes,
there are different vsrays of proceeding ; one is to take your
regular normal developer and dilute with water sufficiently to
develop a normally exposed plate in the desired number of
minutes. For instance, to dilute the normal pyro developer
given for universal developing with double the amount of
water, or twice as much water as you have normal develop-
ing solution, will give you approximately a twenty-minute de-
veloper, and diluting it three times gives a twenty-five-minute
developer. (See Par. 467-470.) The accurate time, of course,
can only be ascertained by a few trials.
488. One can disregard the exact time entirely, and
judge the complete development by examination from time
to time. Yet, it is best to handle plates as little as possible
while developing, for the warmth from the hands changes the
temperature of the solution, thus rendering the film soft, and
easily damaged; and again, it is also well to know the exact
speed of your developer, as more uniform results can be ob-
tained, especially where all classes of exposure are developed
in the same bath, and at the same time.
489. The most successful method to employ, however, is
the factorial system, as explained in former instruction, for
by means of the factor you can secure the exact time necessary
for complete development, and we will, therefore, apply the
factorial method for developing in this instruction.
490. For the convenience of those who have followed the
developing instruction previously given, we will use our reg-
ular pyro formula, given for universal developing, and apply
it to tank development.
491. In this instruction for tank development we supply
the simplest methods that can be used, and which we have
found practical. We would say, however, that to produce
perfect negatives by tank development, it requires more than
the mechanical work; one must exercise their best judgment,
and prepare the chemicals very accurately. We advise ap-
plying the formula given herein without alteration until you
become more familiar with the working of the bath. Remem-
Tank or Stand Developing. 203
ber to always keep the temperature as near sixty-five degrees
Fahr. as possible.
492. It would be well after becoming familiar with the
working of the bath to try a number of experiments, carefully
making a memorandum of the strength of the developer, and
the time required to fully develop a normal exposed plate.
When once you have ascertained the strength of your devel-
oper, and the length of time necessary to produce the kind of
negative that is best suited to the paper you intend to print
on, tank development is then almost a mechanical process.
493. The two formulae supplied are based on the results
obtained by experimenting, and by carefully observing the
rules, and properly preparing the developer you will be able
to produce good negatives. If, however, your first results
are not as you desire, the method of changing the length of
time development is extremely simple. The latitude is so
great that it will rest entirely with yourself as to the results
which you will produce.
494. In a former paragraph we made the statement that a
plate might be developed in ten minutes, or in two or more
hours, producing the same results. For example: In the
former case the developer must be a great deal stronger than
in the latter. To make the developer work slower it is only
necessary to dilute with water. The weaker the developer
the slower will be the process of development. In other
words, more or less water will respectively slacken, or increase
the speed of development. Usually to dilute a normal devel-
oper with an equal amount of water will require a little more
than double the time of a normal developer for complete de-
velopment. We recommend the pyro developer for tank
development. However, for those who like the non-staining
developers, we give also a metol-hydroquinone formula, and
where the latter is employed not longer than a ten to fifteen-
minute bath should be used, as long development with metol
has a tendency to fog, even with bromide added. The pyro
is the most commendable for general results, but should be
made up fresh each day, for the action of pyro as a developing
agent is such that even in a diluted solution, after a few hours'
204 Library of Practical Photography.
standing, whether in use or not, it becomes discolored and
loses its developing power, and cannot be relied upon to pro-
duce uniform results ; therefore, a fresh bath should be made
up each day.
495. A pyro bath can be used continually during one day,
so long as it produces proper results, and develops in the
given time ; usually a twenty-minute bath of ninety-six-ounce
solution will develop twenty-four 5x7 plates before showing
signs of weakening. A pyro bath should never be strength-
ened when it becomes weak but replaced by a fresh bath.
496. The metol-hydroquinone developer can be used contin-
uously for days, for with these agents the action is continu-
ous for a considerable length of time, and only needs re-
newing when the bath ceases to produce the proper strength,
and quality in the given time.
497. The required time for development for either pyro,
or metol, is greatly governed by the temperature of the devel-
oper, and where the factorial methods are employed the tem-
perature is of the utmost importance. For example: If it
requires twenty minutes with the pyro formula to fully develop
a plate with the temperature of the developer at sixty-five
degrees, it would probably take forty minutes if the tempera-
ture were forty-five degrees. This change of temperature changes
the time of development, for the warmer the bath the quicker
the development is completed, and the colder the bath the slower
would be the action of the developer.
498. Caution. It is not advisable to depend entirely upon
the normal time for developing, especially where all classes of
exposures are developed at once, for after a bath is used for some
time it is liable to work a trifle slower, but there is one thing
you can be certain of, no plate, whether under or over-timed,
will be completely developed in less time than those of nor-
mal exposures. Therefore, your developer being prepared for
a normal exposure, plates of all classes can be placed in the
bath at the same time, and when the time for the proper devel-
oping of a normal exposed plate is up, all plates can be re-
moved from the bath and examined one at a time, and if any
of them lack the required strength, or are not completely
J
Tank or Stand Developing. 205
developed, place them back into the tank for further develop-
ment, and examine again from time to time, and as each plate
reaches the proper strength remove to the hypo bath.
499. Bear in mind too that the best negatives are obtained
from fully-timed plates, and that you should also endeavor to
make all your exposures as even as possible, for where the ex-
posures are very near the same the development will be more
accurate. Slow development with pyro is preferable to quick
development, as the addition of water to a pyro developer
produces finer grained negatives, and the detail and gradation
in the highlights and shadows are better.
500. In tank development the plates are placed in a vertical
position. This accounts for the fact that the developer ac-
complishes a quicker and more even action. By this we do
not mean that it develops quicker, but the action of develop-
ment sets in quicker, and more evenly than if the plates were
placed in a horizontal position ; and it, of course, also over-
comes the necessity of rocking the trays or agitating the de-
veloper, for this agitation of the developer, unless done gently,
causes harshness and a coarse grain. The tank developing is
uniformly even, without a tendency to double the tones, pro-
ducing negatives that are clear, with fine highlights and re-
markably fine grain.
501 . If you are in the habit of developing a large number
of plates at a time, you will find a developing tank or stand
method a great time saver, for after loading the tank and tak-
ing the time, you can be working at something else until the
plates are ready for fixing. In order to make certain that you
do not forget the time, an ordinary alarm clock can be brought
into use by simply setting the alarm at the time plates should
be developed. When the alarm rings take out the plates and
place them in the fixing bath, and if you have more plates to
develop fill up the tank and again set the alarm. Where a
large amount of developing is done more than one tank can be
used.
502. The principal requirements for successful developing
with the tank method is to ascertain the proper strength of
the developer, which will develop the plates completely in a
206 Library of Practical Photography.
certain length of time. This can only be obtained accurately
by the factorial method, as explained in previous instruction,
always bearing in mind that the time of appearance is also
governed by the temperature of the developer. The temper-
ature, therefore, should be as uniform as possible.
503. We give below two formulae, the pyro is a twenty-
minute developer, and the metol-hydroquinone will develop in
twelve minutes, which time, however, can be shortened or
lengthened by strengthening or reducing the developing so-
lution. The stock solution prepared for this pyro formula is
exactly the same as that given in formula for universal de-
veloper, and the same proportions are used, only we dilute the
solution twice that of the normal bath. That is, we add three
times as much water as we have bulk of solution in the normal
bath.
504. Formula for Developer. — Pyro Stock Solution
No. I.
Water 6 ounces.
Sulphuric Acid i dram.
Pyro I ounce.
Stock Solution No. 2.
In a 36-oz. bottle pour 2 ozs. Stock Solution No. i, and add thereto
32 ozs. water.
Stock Solution No. 3.
Sulphite of Soda ( Anhydrous ), 40 hydrometer test, or if by weight,
Sulphite of Soda ( Anhydrous ) i ounce.
Water 13 ounces.
If crystal sodas are used it will be necessary to use two ounces, as
anhydrous is twice as strong as the crystals.
For uniform results we would advise that the solutions be
prepared by hydrometer test.
Stock Solution, No. 4.
Carbonate of Soda, 20 hydrometer test, or if by weight.
Carbonate of Soda (Anhydrous) i ounce
Water 23 ounces
If crystal sodas are used, two ounces of carbonate will be necessary.
We would advise that this solution also be prepared by hydrometer test.
Tank or Stand Developing. 207
505. Directions for Use. — Take sixteen ounces Stock
Solution No. 2, eight ounces Stock Solution, No. 3, and eight
ounces Stock Solution, No. 4, making thirty-two ounces of
Stock Solution. To this add twice as much water as you have
solution, or sixty-four ounces water, making ninety-six ounces
of bath. If you have a smaller tank you will require less so-
lution, and if more solution is required to fill your developing
tank, increase the quantity, but always keep the proportions
the same. This solution will fully develop normal exposures
in twenty minutes.
506. Figuring by the factorial method, we find the factor
for this developer to be forty, and time for development
twenty minutes. We would obtain the factor for this bath in
the following manner: We have used sixteen ounces of Pyro
Stock Solution, No. 2, containing five grains of pyro to the
ounce, the sixteen ounces contain eighty grains. To this six-
teen ounces of Pyro Solution, add eight ounces of No. 3, and
eight ounces of No. 4, making a total of thirty-two ounces of
developer. By adding sixty-four ounces of water to this,
making a total of ninety-six ounces of solution, we have di-
luted this normal bath exactly twice. We now^ have eighty
grains of pyro in the ninety-six ounces of solution, or five-
sixths of a grain pyro to the ounce of solution. We found
the image on a normally exposed plate to appear in this devel-
oper, with the solution at sixty-five degrees Fahr., in thirty
seconds, and the development was completed in about twelve
hundred seconds, or twenty minutes. The factor for this de-
veloper, therefore, is one-thirtieth of twelve hundred, or forty,
and a plate developed in this strength bath, and at the same
temperature, will develop in twenty minutes. In case of
plates being very much over-exposed, in order to obtain the
proper snap and contrast between highlights and shadows,
you may need carry the developing farther. It may perhaps
require twenty-five minutes to produce the proper strength ;
then, after fixing, if they are a little too heavy, reduce them
with red prussiate reducer, according to the formula in In-
struction on Reducing. As the red prussiate reduces the
highlights and shadows alike, the plate when reduced will
208 Librar}) of Practical Photography.
be soft, yet have proper contrast between highlights and
shadows.
507. Slightly over-exposed plates will develop in the nor-
mal time. Under-exposures will usually develop in the same
period of time as normal exposures, and ordinarily such ex-
posures will develop better with tank development than by
developing in the tray, because the weaker developing solu-
tion allows the developing agent to thoroughly penetrate the
emulsion, and work up shadow detail, where a very quick
acting developer tends to surface development, and the strong-
est lights have become opaque before the emulsion is suffi-
ciently softened to allow of the required amount of action on
the shadows or under-exposed portions. In case of ex-
treme under-exposure a more diluted bath is still better and
will produce better results, but will require more time to com-
plete the development.
Proportions for Different Size Tanks.
For a forty -eight-ounce tank, use the following: —
No. 2 8 ounces.
No. 3 4 ounces.
No. 4 4 ounces.
Water 32 ounces.
For a twenty- four-ounce tank, use : —
No. 2 4 ounces.
No. 3 2 ounces.
No. 4 2 ounces.
Water i6 ounces.
508. The temperature of the developer should never be
below sixty degrees or higher than seventy degrees Fahr.,
sixty-five degrees being normal. In some localities the water
may be such that you will find it necessary to add more or
less water with the same amount of Stock Solution, in order
to develop in the given time. This is only in extreme cases,
and should it occur, and if the factorial method for tank
development is employed, it will not matter whether the
water used is strongly alkali or even acid, for the factor for
the developer employed remains the same, only the time of
Tank or Stand Developing. 209
appearance is changed, and all that will be required under
such conditions is to know the time of appearance, and multi-
ply by the factor, which will give you the exact time required
for complete development, and all plates developed with the
same water conditions thereafter will be fully developed in
the same time. A little experimenting, and carefully keeping
a memorandum of your results, will soon enable you to regu-
late the speed of the developer.
METOL-HYDROQUINONE DEVELOPER.
Stock Solution.
Water 24 ounces.
Metol 15 grains.
Sulphite of Soda ( Anhydrous ) i J^ ounces.
Hydroquinone , i dram.
Bromide of Potassium . 4 grains.
Carbonate of Soda ( Anhydrous ) 5 drams.
If crystal sodas are used in place of anhydrous, use double
the quantity given in the formula, as the anhydrous is twice
as strong.
509. Directions for Use. — For a twelve-minute developer
this metol-hydroquinone formula must be diluted as follows :
To every ounce of the developer add four ounces of water.
If it is necessary to have twenty-five ounces of solution to fill
the tank, take five ounces of the developer and add twenty
ounces of water. If more solution is necessary to fill the tank
increase the quantity by adding more developer and water,
but always keep the proportions the same, and the tempera-
ture of the developer should never be under sixty degrees, or
above seventy degrees Fahr. This bath will fully develop a
plate in from ten to twelve minutes.
510. The Film Developing Holder. — The individual
films are taken from the film pack, and a film placed in the
holder. The holder is then inserted in the developing tank in
exactly the same manner as the plate, and development proceeds
accordingly. These holders are made in all the popular sizes,
and as they list at a very reasonable price there is no reason
why this very convenient accessory should not be in the
hands of every user of the film pack.
210 Library^ of Practical Photograph}},
DEVELOPING TANKS.
511. Description of Developing Tank. — These tanks are
generally made of brass, nickel plated or zinc, strongly built,
and with little care will last many years. The following illus-
trations are of the Ingento developing tank : Each tank is sup-
plied with a grooved rack. The rack is arranged for different
size plates, and is made to fit inside of the tank, and can be
raised or lowered in the bath. In this way the plates can
be examined while developing, without placing the fingers in
the developer. The tanks are made in five sizes, as follows : —
No. I, for six 3J^X4)^ plates, or twelve if placed back to back.
No. 2, for six 4x5 plates, or twelve if placed back to back.
No. 3, for six 5x7 plates, or twelve if placed back to back.
No. 4, for six 6% ^ 8)^ plates, or twelve if placed back to back.
No. 5, for six 8x 10 plates, or twelve if placed back to back.
Tanks Nos. i and 2 require only twenty-eight ounces of
developer ; larger sizes a proportionate amount.
512. Style "A" Developing Tank. — In illustration No.
15, we show the developing tank ready to receive the developer.
These tanks are made in two grades. Style A is strongly
made of brass, nickel plated, and fitted with a removable rack,
with wide grooves to hold the plates separate and in a vertical
position. Tanks of this style can be used for developing,
fixing and washing. The developer can be poured off and
sufficient hypo solution poured in to fill the tank. After the
plates are fixed, the hypo solution can be poured oif, and the
tank then used as a washing box, by allowing the water to
enter through the funnel. In this way the water will thor-
oughly eliminate the hypo from negatives and tank simulta-
neously. Additional new sizes of style A developing tank
are made as follows : 3^x5^ and 4^x6^.
513. Style "B" Developing Tank.— The style B, see
illustration No. 16, is made of heavy zinc, fitted with wide
grooves which extend from the top downwards, and with the
patent lifting bottom, which allows the negatives to be re-
moved without dipping the fingers in the solution. The style
B tank can be used for washing, as well as developing, in the
Illustration No. 14
Lmproved Developing
Tank
Illustration No. 16
Style B. Developing Tank
see Paragraph No. 513
Illustration No. 15
Style A. Developing Tank
See Paragraph No. 512
Illustration No. 17
The Gennert Tank
Illustration No. 19
Rubber Fixing Tank
See Paragraph No. 515
EAL-gi.^
Illustration No. 20
Ideal Adjustable Washing Box
See Paragraph No. 516
Illustration No. 18
The Ideal Fixing Tank
See Paragraph No. 514
1211)
212 Library of Practical Photography.
same way as described in style A, hut cannot be used for fix-
ing, as zinc will gradually disentegrate under the action of a
hypo solution. Where style B is used an extra fixing tank
must be employed.
514. Fixing Tank. — The Ideal Fixing Tank is made of
heavy tin, with deep corrugations, thoroughly enameled with
acid-proof varnish. It is equipped with a patent lifting bot-
tom, and is both convenient and practical. Its capacity is
twelve plates. (See Illustration No. 18.) The Ideal, Jr.,
Fixing Box is made on the same plans, but has a capacity of
only six plates, instead of twelve.
515. Rubber Fixing Box. — The most reliable fixing
box is the hard rubber, see illustration No. 19. They are
made of the same material as the rubber trays, and are very
durable, and are not affected by any chemicals used. In fact,
with reasonable care they will last a lifetime.
516. Washing Box. — The Ideal Adjustable Washing
Box, see illustration No. 20, is the most practical plate
washing box on the market. The water enters at the bottom
and overflows at the top. It is supplied with patent raising
bottom, and, is adjustable for small sizes.
PRACTICE WORK.
517. Developing. — When you are ready to develop, first
prepare enough solution to completely cover the plates. After
the developer has been prepared test it for temperature, using
an ordinary thermometer for the purpose. If you find it too
cold add a little hot water ( the slight addition of water will
make no difference in time of development), or if it is too warm
put it in a cold place, or add a small piece of ice, until the
temperature is correct. Next light your dark room lamp, close
the door, and transfer the exposed plates to the grooved rack;
then carefully lower the rack containing the plates into the
tank. Lower the plates until they are completely covered
with developer, raise the rack slowly two or three times, lift-
ing the plates almost entirely out of the developer. This will
remove any air-bells that may have gathered on the plates.
These air-bells, if not removed, would cause pin holes or spots.
Tank or Stand Developing. 215
The plates are raised or lowered by means of a wire rod at-
tached to the center of the rack, by catching hold of the ring
at the top of rod, thus you avoid wetting the hands in
the developer. After all air-bells are removed lower the rack
and close the cover on the tank, and also on the funnel. Take
the time and allow them to develop for, say five minutes when
the plates should be turned end for endj thus insuring even de-
velopment and allow the development to continue for the total
time of twelve minutes, if the metol formula is used ; and for
twenty minutes if pyro formula is used ; then fix in the usual
way.
518. Until you have become thoroughly accustomed to this
method, and are certain as to the strength of your developer
and the time required to develop, it is advisable to examine
the plates before fixing. It is, however, only necessary to ex-
amine the plates at intervals. After you thoroughly under-
stand the speed of your developer and you have been careful
in supplying the proper proportions of each chemical, and your
plates are uniformly exposed, it will not be necessary to ex-
amine the plates at all until they are completely developed.
519. We would caution you against examining plates too
often during development, especially Orthochromatic plates,
as even the ruby light is apt to effect them, and the result will
be foggy negatives. At the expiration of the time required
for the development of normal exposures, examine each plate
before you place it in your fixing tank. See that they are
fully developed and make due allowance for the density they
will lose in the fixing. Before placing them in the hypo, care-
fully rinse them in clear water. If some of the plates, upon
examination, are not fully developed, after you have removed
those which are developed, simply lower the rack containing
these plates back into the tank, and continue developing.
Usually when one plate is developed all are done. It is only
in extreme cases that it would be otherwise, and then usually
from an over-worked bath.
530. If you have a batch of twenty-four negatives to de-
valop, and your tank has twelve grooves, you can place the
plates back to back, putting two plates in this way in each
216 Library of Practical Photography.
groove. This will enable you to develop the twenty-four
plates at one and the same time.
521. While it is safer to develop and fix in separate tanks,
one and the same tank can be used, if necessary, providing
the tank is made of some material which will not rust, such
as nickled copper or hard rubber. This method is not recom-
mended, however, as there is danger of one becoming careless
and not thoroughly cleansing the tank before and after fixing.
In case you must use one tank for both, an ordinary rubber
fixing box thoroughly cleansed free of all hypo can be used as
a developing tank. One advantage of developing and fixing
in the same tank is that there is less handling of plates than
when fixing and developing in separate tanks. However,
this is of little account. Never fix in a tin or iron tank. If
you desire to develop and fix in one and the same tank, ob-
serve the following: —
522. After the plates are fully developed, pour off the de-
veloper into a large bottle, and save for the next developing;
then rinse the plates in three changes of water. This you can
do by filling up the developing tank with fresh water, pour-
ing off the water and repeating the operation three times.
After the last change of water fill the developing tank with
hypo solution, and allow the plates to remain in this until
they are thoroughly fixed. Next transfer them to the wash-
ing tank and carefully wash.
ADDITIONAL FORMULAE FOR SLOW TANK
DEVELOPMENT.
523. With the following formula there is little or no
danger of fog from long development if the tank is covered,
excluding all light: —
Metol-Hydroqjuinonk Tank Developer No. 2.
Metol 4 grains
Hydroquinone 4 grains
Sulphite of Soda (anhydrous) ^ ounce
Carbonate of Soda (anhydrous) }^ ounce
Water 64 ounces
If crystal sodas are used, use twice the amount.
Tank or Stand Developing. 217
524. Unquestionably one of the best developers for long
development, and one which will not fog, is glycine. This
developer is prepared slightly different than when used for
tray development. This is especially noted for the reason
that if the ordinary glycine formula is used for many plates it
will sometimes impart a yellowish tinge to the negative This
is overcome in this formula by using noi more than equal
weight of sulphite to glycine, when preparing the solution.
Glycine Formula for Tank Development No. 3.
Water ( hot ) 7 ounces
Sulphite of Soda (anhydrous) 30 grains
Carbonate of Soda (anhydrous) 30 grains
Glycine 30 grains
After the above have been dissolved add water, twenty-eight ounces.
Note. — If crystal sodas are used, employ double the weight, or
sixty grains in place of thirty grains.
525. In using any of the above developers in the tank it is
advisable that the temperature be not more than sixty degrees
Fahr. , in order to obtain the best results. If the weather is
very warm the tank should be placed in a vessel containing
very cold water for a time, and in cold weather, when it is
very cold, the tank should be placed in a vessel containing
warm water, thus equalizing the temperature. These form-
ulae for long development are not as reliable for exact time
for complete development, but as there is so much latitude,
by occasional examination the best results can be obtained from
any exposure. For instance, if a normal exposure would de-
velop in thirty minutes a very much under-timed plate could
develop for an hour, or even all day, and improve with time.
So when using the above formula, it is advisable to examine
each plate in the tank before removing, and if any are not
perfectly developed place them back into the tank until fully
developed.
When using glycine developer special care should be ex-
ercised that no trace of hypo is conveyed to the developer or
218 Library of Practical Photograph}}.
yellow stains will surely follow. For fixing use the regular
acid-fixing bath.
ACID-FIXING BATH.
526. The plain fixing bath has the disadvantage of becom-
ing dark and discolored when organic developers are used,
and consequently, it is liable to stain the plate. This is over-
come by using the acid-fixing bath according to the follow-
ing formula : —
Water 80 ounces
Hypo . . 4 ounces
Dissolve, and then add citric acid i^ ounces. After this
has been dissolved add hypo 16 ounces. When the ingredients
are all dissolved the bath is ready for use, and plates should
be fixed at least ten minutes after all the free silver or milky
appearance has been removed.
527. Life of the Developing Solutions. — The pyro de-
veloper should only be used for one day's developing. The
metol-hydroquinone developer can be used repeatedly, so long
as it gives good results. You must, however, make due allow-
ance for the fact that each lot of plates is adding bromide to
the developer, the bromide being eliminated from the emul-
sion of the plates previously developed. The developer dis-
solves the bromide in the plate, and it therefore becomes a
part of the solution and will retard the development. This
will especially be noticed after the bath has been used for
some time, and with short factor developers will tend to
materially alter the factor. Carefully watch your negatives
and when you find that the developer is acting slow or devel-
oping contrasty — in other words, when the bath fails to
produce the proper results, make up a new one. Always
keep the bath covered, excluding all light, whether in use or
not.
528. If you are using a zinc developing tank, carefully
rinse it after you are through developing and turn it bottom
side up so that it will become dry. A little care will enable
you to preserve this tank for years.
Tank oT Stand Developing. 219
529. Practice Work. — In preparing the lesson 6n tank
development first provide yourself with a tank holding six
5x7 plates, or their equivalent. Next make a few exposures,
which you know to be normally exposed, then prepare
enough of the pyro developer to make solution sufficient
to fill your tank. If a small tank, twenty-eight ounces will
be sufficient. If the developer was made according to for-
mula, you can be certain that the plates will be developed in
twenty minutes ; but you should prove the accuracy of this and
for the benefit of your own experience make a practical test.
By watching the plate carefully from the moment it enters
the developer, and noting the time of appearance of the
strongest light with general outlines slightly visible ( which
should be thirty seconds), see how near your judgment was
right ; then, the next step is to examine the plates at the ex-
piration of twenty minutes and see if in your judgment the
plate is completely developed. This will supply you excellent
practice and will train you in the accurate judgment of the cor-
rect development of the plate under all conditions. After each
experiment dry the negative and make good solid proof prints,
untoned, from the plate, and note the quality of the proofs
produced. Make notes on the back of each proof, naming
the formula employed, which in this case would be pyro, the
time for complete development, and any other data concern-
ing the development of that plate. Note also whether the
plate was normal, over or under-exposed. File these proofs
in your letter-file for future reference.
530. After trying out the pyro formula prepare the metol-
hydroquinone formula, and observe the results in the same
manner, making proof prints in every instance, and filing the
same with all data connected with the producing of the re-
sults. This data will be for your future guidance. After
completing your experiments compare the results and
judge for yourself which formula you prefer to use regu-
larly; and by this time, if you so desire, you may try
altering the formula, which is good practice, and will only
have the eflFect of making you more proficient in your
judgment.
220 Library of Practical Photography.
If you meet with any failures make use of the Index, and
refer to the Difficulty Department, where you will undoubt-
edly find a prevention or remedy for your difficulty.
DIFFICULTIES— TANK DEVELOPING.
531. Plates Developing Too Slowly. — If the plate de-
velops too slowly it is either because the developer has been
diluted too much, it is too cold, or it has become exhausted by
long use. Carefully test the temperature and if this is correct
your bath has become exhausted, therefore, make up a fresh bath
exactly according to formula. With a fresh bath made ac-
cording to formula slow development will not occur.
532. Plates Develop Too Fast. — If the developer is
too strong, or too warm, the plates will develop too fast.
Remedy: obvious.
533. Plates Develop Unevenly. — If the developer is not
thoroughly mixed, the plates will develop unevenly. When
adding water to make up the bulk of developer thoroughly stir
the solution to insure proper mixing. It is well to occasion-
ally shake the tank during development.
534. Plates Develop in Streaks. — If the developer is
too strong, and develops too quickly, the plates are apt to
develop in streaks. Dilute the developer by adding more
water and mix well. It is not advisable to use a faster bath
than twenty minutes for pyro, or ten minutes for metol.
Always shake a bath well before admitting the plates.
535. Pin Holes. — When the plates are first immersed in
the developer air-bells are apt to gather on the surface of the
plate, and if these are not removed will cause pin holes and
transparent spots. When first placing the plates in the tank
raise and lower them two or three times very carefully ; this
will remove the air-bells. Sometimes air in the water will
Tank or Stand Developing. 221
cause air-bells ; to use cold boiled water will overcome this
difficulty,
536. Spots and Pin Holes on Plates That Are not
Caused by Air-Bells. — These are sometimes caused by par-
ticles of dirt in the developer. Always filter old developer
before using.
537. Negatives Contrasty — If the plates are properly
exposed this can only occur when the developer is not properly
balanced, and there is too much of the developing agent in the
developer. Even diluting with water will not overcome this,
and it clearly shows that you must have made a mistake in the
quantity of developing agent used. It will be advisable for
you to make up a fresh bath. An excess amount of bromide
will also give similar results. An over- worked bath also con-
tains considerable bromide, eliminated from plates previously
developed.
538. Negatives Develop Flat, — Either the plates are
badly over-exposed or the developer is weak in developing
agent. Possibly the stock solution which contains the devel-
oping agent was not correctly prepared, not enough of
the developing agent added. Where long factor developing
is resorted to (using weak solutions), the image, during the
first three-fourths of the period of development, is flat, the
contrast gaining rapidly at the latter end. Developing longer
will give you stronger negatives, but you will likely find your
trouble was in preparing your developer.
539. Negatives Full of Detail, But Very Thin. — The
plates were either over-exposed or under-developed, or both.
It is advisable to carry plates which appear flat and are over-
exposed, farther in the developing. If they are then too dense re-
duce them according to instructions given in Reducing. With
a bath in good condition, and the proper time given for devel-
opment, you should obtain good negatives. Be sure you make
no mistake in the time.
540. Negatives Too Yellow When Developed in the
Pyro Developer. — When this occurs it signifies that the
sulphite is not strong enough, or the sulphite solution is old,
and has deteriorated. We would advise that you prepare a
222 Librar}) of Practical Photograph}).
new stock solution of sulphite, being careful that it is made the
proper strength. The color of the plate is controlled entirely
by the strength of the sulphite. It requires a certain amount
of sulphite to give you the right color, and to balance the de-
veloper.
Note. — If crystal sodas are used in place of anhydrous you
will require twice the amount.
541. Negatives Too Blue. — As the sulphite controls
the color of the negative, blue or gray negatives would signify
that the sulphite stock solution is too strong. Carefully test
it, and if too strong dilute with water, and try it again, until
the desired result in proper color is obtained. Your carbonate
may also be weak or impure, but if the negative is right in
every other respect but color, then your sulphite alone is at
fault.
542. When Developing with Pyro Plates Develop to a
Certain Stage and Then Stop. — This will only occur when
the developer is too weak or is over- worked, and the developing
agent has become exhausted. Pyro in solution deteriorates
quite rapidly ; therefore it is liable to work slow after a few
hours' use, especially in warm weather or hot climates. Do
not over- work the bath in a warm climate. Not more than
twenty-four to thirty 5x7 plates should be developed in a one
hundred ounce bath. After developing this number of plates
the bath better be discarded.
543. Plates Developing Contrasty in Hydro-Metol
Developer After the Bath Has Been Used for Some
Time. — This is caused by the bromide which was released
from the plates previously developed, and which, when dis-
solving, became a part of the developer, thereby restraining
the development. A bath in this condition is unreliable and
a new one should be prepared.
544. Top Edges of Plates Not Developed. — This
will occur if there is not sufficient developer in the tank to
completely cover the plate.
545. Some Plates Develop Quicker Than Others. —
This will occur when the exposures vary. Carefully examine
plates just before placing in hypo. Those that are not fully
Tank or Stand Developing. 223
developed return to the developing tank, and prolong the de-
velopment. Ordinarily a slightly under-exposed plate and a
normal exposed one will be completely developed at the same
time, but invariably an over-exposure will require a little
longer developing, and possibly reducing afterwards.
546. Scum Gathering on the Developer While in
the Tank. — This is apt to happen if the tank is left un-
covered for a considerable length of time, and is caused by ox-
idization. This scum will do no harm if the bath is stirred up,
and if the plates are raised and lowered two or three times
when placed in the developer. Should you fail to do this the
scum will settle on the plate and cause transparent spots,
stains and uneven development. The safest way is to keep
the tank covered always, and when sediment or scum collects
filter before using.
547. Sediment Gathering in the Developing Tank
and Bottle Which Contains Hydro-Metol Developer. —
This is a precipitation which will occur, but will do no harm
and have no injurious effect in the development.
548. Testing Development for Temperature. — This
is a very simple matter. Provide yourself with an all glass
dairy or bath thermometer, which can be purchased very
cheaply. After you have diluted the developer place the
thermometer in it. If too cold, add a little hot water. The
extra water will make very little difference in diluting the de-
veloper. If too warm, add a small piece of ice or a few ounces
of very cold water until you have produced the correct tem-
perature; or place the tank in a tray of ice water.
CHAPTER XX.
TANK DEVELOPING FOR THE
PROFESSIONAL.
1909 Addition.
DOMINANT PRINCIPLES IN TANK DEVELOPMENT.
The effect of light values in the studio as pertaining to cor-
rect tank developing.
To insure the best possible results by this system of
development, many principles must be closely adhered to
which are frequently overlooked or, at least, neglected. The
most important considerations are temperature, strength
of chemicals, and the chemical properties of the light used
in making the exposure and their relation to the proper time
of development. The writer's experience has been that
when the light used in making the exposure is in large vol-
ume its effect in the development is equivalent to that pro-
duced by an alkali, and there is an excess of detail and slow-
er building power. Under such conditions of light the best
results are obtained when the quantity of stock chemicals
used are doubled and the time of development necessary
in obtaining proper density is reduced, when much more
brilliancy will be obtained. On the other hand, when the
light is narrow and used more concentrated rather than in
large volume the same relation of balance does not exist
between high-lights and shadows, and the slower action
of the chemicals (resulting from a more diluted solution,
224a
224b Library of Practical Photography.
which requires longer time for development) usually gives
best results.
From the above it will be seen readily that in addition
to time and temperature due attention must also be given
to the light conditions under which the exposures are made.
Thus, the more closely the individual problem of the pho-
tographer is adhered to, and conditions of chemicals, tem-
perature, chemical properties of light and its effect upon the
time it will take with a given strength of chemicals to obtain
the proper density, just so satisfactorily will results be ob-
tained.
The fact that in one studio where a large volume of
light is employed when making the exposure, a developer
(prepared with two ounces each of the different stock solu-
tions with a given amount of water added, and the tem-
perature of the solution of 65° Fahr.) should develop
in twenty minutes and give excellent results does not mean
that the same results would be obtained under different
conditions in another studio where a more concentrated or
a different actinic value of light was employed in making
the exposure. Due to the different chemical properties of
light, the same conditions may require 25 to 30 minutes
to secure the same quality; so the most careful adaptation
to the individual conditions under which one is working
yields unquestionably the best results.
Developing Tanks for the Professional. — The profes-
sional photographer, as a rule, seeks the easiest and sim-
plest methods possible for accomplishing results ; there-
fore, many of them who have adopted tank development
employ the regulation rubber fixing tank, with a tight fitting
cover, which, if properly handled, answers every purpose.
The principal objection to this tank is the possibility of
streaks and air-bells. This objection may be overcome,
however, by raising and lowering each plate when first
placing it in the tank, and then occasionally shaking the
latter gently to mix the solution thoroughly.
The regular rubber hypo tank method can be improved
Tank Developing for the Professional 224c
upon by providing a wooden box, made three inches larger
each way than your regular hypo tank, painted both inside
and outside with shellac, or black mogul varnish, making
the box water tight. Then provide a grooved box, similar
to the rubber hypo tank, minus the bottom ; in other words,
provide a rack or cage, properly grooved, into which you
can place your plates for developing. Should you have an
old rubber hypo tank, which is discarded on account of its
being cracked or broken in some particular place, making
it unfit for use, take this tank and cut out the bottom to
within a half inch of the side walls, and also cut the rim
off the top of the rubber tank, thus making of it a cage or
rack for holding the plates.
The developer is placed in the large wooden tank, and
when ready to develop the rubber rack, or whatever rack
you provide for this purpose, is filled with plates and gradu-
ally lowered into the developer, and the rack loaded with
plates is raised up and down a few times in the solution,
to eliminate any air-bells that might collect. With this
done the tight fitting cover is placed on the tank and the
time taken. After the plates have developed, say for five
minutes, the cover is removed and the cage containing the
plates is turned on its side. The cover is again put on for
another five minutes, when the cage is turned on the other
side. In this way even development is obtained. After
development the cage may be placed in a hypo tank, made
the same as the developing tank, and when fixed the plates
may be washed in the usual way.
Note. Should the cage be made of galvanized iron,
then the plates must be removed from the cage and fixed
in a separate hypo tank, as it would not do to place a
galvanized iron rack in hypo. Rubber or nickled-brass cages
may be used for both developing and fixing.
Developers. — Any of the formulae given in this volume
for Tank Development will give satisfactory results. First
determine upon the results desired, and then prepare the
formula to produce such results. For example, where soft-
224 J Library of Practical Photography.
ness is desired pyro-metol makes a good combination, for
the metol assists in producing detail when one is incHned
to under-time. The following formula for acetone-pyro
developer, suggested by the Cramer Dry Plate Company,
has proven very satisfactory:
PYRO-ACETONE DEVELOPER.
No. 1.
Water i6 ozs.
Oxalic Acid 12 grs.
Metol 120 grs.
Pyro I oz.
No. 2.
Sulphite of Soda, 70 hydrometer test.
No. 3.
Water 20 ozs.
Acetone 4 ozs.
For tank development take 3 ozs. of each of the above
solutions, and add 70 ozs. of water at 70° Fahr. A develop-
er made up according to this formula will develop plates
to full density in 30 minutes.
// the pyro-acetone is desired for tray developing take i oz.
each 0/1,2 and 3 ^0 5 ass. of water.
Note: Observe that the acetone is mixed separately
from the pyro or sulphite of soda. It has been found, by
experience, that these chemicals are more active when pre-
pared in stock solutions separately and mixed together when
ready for use. The advantage of the acetone over the car-
bonate of soda lies in the fact that plates developed with
pyro-acetone will not streak nor develop unevenly in the tank,
and it also prevents fog, as plates may be developed with
acetone for any length of time without chemical fog. The
acetone also prevents frilling, and in case of very short ex-
posures a warmer solution may be employed to good ad-
vantage, without danger of frilling or chemical fog. It
will be important to remember that when acetone is used
in the d^ velnper in place of soda, the temperature must not he
below 65°, for if worked at a lower temperature the acetone
becomes inactive. The experience of the writer has demon-
strated that at 70° Fahr, the acetone works at its best.
Tanl^ Developing for the Professional 224e
Developing Short Exposures. — Since the inauguration
of the tank method of developing, which is especially com-
mendable for under-exposures, photographers are becoming
somewhat careless in their timing, and are inclined to under-
expose most of their work. Owing to this fact the small
addition of metol has been added to the pyro formula,
which assists in getting out more detail in plates of short
exposure. Where full time is given, if one so desires, the
metol may be omitted entirely and the formula used as
given (minus the metol). Metol has a tendency to give
flatness when used on plates fully timed, or but slightly
over-exposed; therefore, when one is accustomed to giving
full time it is advisable to omit the metol from the formula.
Fixing Bath. — While the plain fixing bath prepared
with water and hypo may be successfully employed, yet we
find in certain localities, which are troubled with organic
substances in the water used, causing spots and stains
on the film, that the following chrome alum bath has been
found more satisfactory:
No. 1.
Water 128 ozs.
Hypo 2j^ lbs.
Or, by hydrometer test.... 90
No. 2.
Water 32 ozs.
Sulphite of Soda
(Anhydrous) 3 ozs.
Sulphuric Acid CP J^ oz.
Powdered Chrome Alum 2 ozs.
Dissolve thoroughly in order given and add No. 2 to No. i,
stirring while adding.
Note. The above bath is intended for hot climates or
summer months; for cold climates or winter months use
half the quantity of No. 2.
Removing Organic Stains. — While the above bath will*
prevent any stains of an organic nature, should you have
some plates so stained previous to using the above bath,
these stains may be removed by first immersing the plate
in water for, say, ten minutes, and then flowing over the
224/ Library of Practical Photography.
surface a strong solution of citric acid. This will remove
all stains and any excess color from the plate.
DEVELOPING TANKS FOR PROFESSIONAL USE.
Of the different developing tanks manufactured for
professional use, we describe a few. Each tank is construct-
ed with the intention of overcoming the usual difficulties
met with in tank developing, which are, principally, retain-
ing of even temperature during development, the overcoming
of streaks, uneven developing of the plate, and also the
prevention of air-bells.
The Burke & James Style C Tank.— With this style of
tank, if desired, the plates may be developed and fixed in
the same tank. The exposed plates are put into the plate
rack, which, in turn, is placed into an inner tank. This
part is done in the dark-room. The cover being securely
fastened, the light may be turned on, the door of the dark-
room may be opened, or the tank may even be brought into
broad daylight. The inner tank is then lowered into the
outer tank containing the developing solution, and left for
half the developing period, when the inner tank is withdrawn
and reversed. The reversing of the plates insures uniform-
ity of development.
A light-tight opening in the bottom of the inner tank
admits the developer, and an opening at the top allows the
air to escape, permitting the tank to fill rapidly. The tank
being made of brass, nickel-plated, it can, if desired, be
used for fixing as well as developing. (See Illustration No.
21.)
Eagle Developing Tank. — ^The Eagle Adjustable Tank
is made in two styles, zinc and nickel-plated. The zinc is
intended for developing only, as the fixing bath would be
affected by the zinc. The nickel-plated tank can be used
for developing, fixing and washing.
The plates are loaded in the rack and then placed in
the tank containing the solution, the cover being placed
on the tank, and the plates are then on their way develop-
Illustration No. 21.
B. & J. Developing Tank.
Style C.
See Page No. 224/.
Illustration No. 23.
Eagle Developing Tank.
See Page 224'.
Illustration No. 22.
Eagle Developing Tank.
See Page 224?,
Illustration No. 24.
Lowering Rack of
Plates Into Solu-
tion Cup.
See Page No. 224?.
Illustration
No. 25.
Loading Plate
Into Rack.
See Page 2241.
Eastman Devkloping Tank
Tank Developing for the Professional. 224/
ing. As the cover fits tightly the tank can be turned upside
down a few times during developing, thus insuring even
development. When the plates are developed they may be
removed to the regular fixing tank; or, if the nickel-plated
tank is used, and when so desired, the developer may be
poured off and sufficient hypo solution (hypo, 1 oz,, water,
4 ozs.) to cover the plates poured in. When properly
fixed, pour off the fixing solution and wash the plates by
allowing the water from the tap to flow through the funnel.
This method removes the hypo from both plates and tank
at the same time.
The professional sizes of these tanks are known as the
Nos. 11 and 12. The No. 11 will hold 48 5x7 size, or small-
er; the No. 12 will hold 24 8x10 size, or smaller. The
professional sizes are made with a handle, which, when
the rack is lifted partly out of the tank, falls over the side
and locks, holding the rack up out of the developer. (See
Illustrations Nos. 22 and 23.
Eastman Plate Tank. — The Eastman developing tank
is made in different sizes to accommodate all of the stand-
ard sizes of plates. Those recommended for the profes-
sional are the 5x7 and 8 x 10 sizes. In Volume I of this
library we fully illustrate the use of the smaller size tank.
The 5x7 tank is manipulated in practically the same way,
although it is slightly different in construction, and is fitted
with a cage for holding twelve 5x7 plates, and requires
64 ounces of solution. (See Illustrations Nos. 24 and
25.) The 8 X 10 tank has an adjustable metal cage for the
holding of plates from 4^4 x Syi to 8 x 10, and requires 156
ozs. of solution. (See Illustrations Nos. 26 and 27.)
Developing Formulae. — The following Pyro or Glycin
formulae will produce good results :
PYRO FORMULA FOR TANK OEVELOPINQ.
A
Water i6 ozs.
Pyro I oz.
Oxalic Acid lo grs.
224/ Library of Practical Photography^.
B
Water i6 ozs.
Eastman's Sulphite of Soda 3 ozs.
C
Water 16 ozs.
Eastman's Carbonate of Soda i oz.
For 5x7 tank use —
A I oz.
B I oz.
C I oz.
Water 61 ozs.
I'or 8x 10 tank use —
A 2y2 ozs.
B 2 J^ ozs.
C 2j^ ozs.
Water To Make up 156 ozs.
Note. — If crystal sodas are used take three times the
quantity of carbonate and double the quantity of sulphite.
With the temperature at 65° Fahr. this formula will develop
plates completely in 30 minutes. With the temperature at
70° Fahr. the plates will be fully developed in 25 minutes.
GLYCIN TANK DEVELOPER.
Stock Solution.
Hot Water, about 200° 60 ozs.
Carbonate of Soda (Eastman's) 2 ozs.
Glycin V2 oz.
Sulphite of Soda (Eastman's) J^ oz-
Dissolve in the order given.
For the 5x7 tank use —
Stock Solution 6 ozs.
Water 58 ozs.
(For the 8 X ID tank use —
Stock Solution 15 ozs.
Water 141 ozs.
With the temperature at 65° Fahr. this developer will
completely develop plates in 30 minutes.
FIXING BATH RECOMMENDED.
By Weight. By Hydrometer.
A A
Water 96 ozs. Hypo, Test 80 100 ozs-
Sulphite of Soda 2 ozs. Sulphite of Soda,
Hypo 2 lbs. Test 60 16 ozs.
B B
Water 32 ozs. Chrome Alum,
Chrome Alum 2 ozs. Test 20 32 ozs.
Sulphuric Acid C. P. . . J4 oz. Sulphuric Acid C. P. 2 dms
Illustration No. 26.
Placing Septum over Lower
Tier of Plates.
Sec Page No. 224«.
Illustration No. 27.
Fastening Cover
of Solution Cup.
See Page No. 224*.
Eastman Developing Tank.
Tank Developing for the Professional 224m
When dissolved pour B into A, slowly, while stirring
A rapidly. This bath may be used continuously so long as
it fixes plates in 15 minutes' time.
USE OF THE EASTMAN PLATE TANK.
By S. G. Lofft, of the Plate Division, Eastman Kodak Co.
With a view to eliminating many of the inconven-
iences of the ordinary tanks, the Eastman Plate Tank has
been designed to meet the requirements of professional and
amateur photographers, and is furnished in sizes which
may be adapted to all sizes of plates commonly in use up
to 8x10.
Some of the leading features in the Eastman tank are,
viz: Perfection in construction, durability (being made of
brass, nickel-plated, and practically non-corrosive), conven-
ience in loading, complete exclusion of air during develop-
ment, thus preventing oxidization of developer, maintaining
an even temperature, providing for perfect agitation during
development, thus securing even development, and, not the
least of its advantages is that it enables the photographer to
develop with pyro without staining the hands in the least
degree.
Each tank is furnished with a carrier or cage, also made
of brass, nickeled, holding twelve (12) plates, and a loading
device, by means of which plates may be loaded into the
cage in absolute darkness if desired. This is a great ad-
vantage where orthochromatic plates are in use, as it elim-
inates the danger of fog while loading and developing.
A hinged cover on the cage secures the plates after
loading, and the bail or handle attached to this cover enables
one to handle the rack full of plates with facility, and is used
to lower cage into tank of developer.
It has been demonstrated that beyond a certain point ''
of dilution, a developer of certain strength and certain tem-
perature will develop a variety of exposures to a proper
point in a certain length of time. After a long series of ex-
224n Library of Practical Photography,
perimenting, it has been discovered that a developer so
compounded as to develop in about 30 minutes will cover
the widest range of exposures with the most satisfactory
results.
The manufacturers of this tank do not claim for it that
it will develop all kinds of exposures exactly alike, but
while there will be a difference in density between extremes
of over-exposure and under-exposure, this slow method of
development will equalize such exposures to a remarkable
degreee, and average exposures will be developed with such
slight variation in printing quality as to be scarcely per-
ceptible.
^ It will be noticed in using this tank, that the length of
exposures may be reduced materially, as it is a well known
fact that dilute developer will produce detail in the shadows
without over-developing the higher tones where plates have
received a minimum exposure, much better than the strong-
er developer usually employed in tray development. Suc-
cessful tank development in a given length of time necessi-
tates care in the selection of chemicals that are of a known
uniform strength. As many brands of sulphite of soda on
the market contain a great percentage of sulphate of soda,
and as different makes of carbonate of soda vary greatly in
their active alkaline properties, it is recommended that only
reliable brands of sodas be used. The accompanying for-
mulae is prepared with Eastman's sodas. Where other
sodas are used, it is advised to test their strength by experi-
mental development till it is determined just how much to
use to secure the desired strength of development in the time
specified.
It is equally important that the temperature be accu-
rately adjusted, as a few degrees one way or another will
make a marked difference in the time of development. For
instance, a developer that would complete development in 30
minutes at a temperature of 65° would produce approximate-
ly the same density in 25 minutes at 70°. A temperature of
65° is, however, as a rule more satisfactory the year around,
Tank Developing for the Professional 22Ao
as plates do not soften at this point, and the resulting nega-
tives are finer in grain and firmer in texture, as there is no
tendency to swell the cells of gelatin beyond a normal de-
gree, as in a higher temperature.
It is important in this connection, that plates be kept in
a moderate temperature before and after exposure, as it
is obvious that if they are extremely cold, or very warm,
they will lower or raise the temperature of the developer,
and thus develop slower or more rapidly as the case may be.
This, by the way, is important even in tray development,
as without doubt the character of negatives is largely in-
fluenced by the temperature of the plates themselves.
Within the experience of the writer, one lot of plates
developed in the tank in 15 minutes in a normal 30 mmute
solution, owing to the fact that the plates were kept in a
changing room that was exposed to the heat of the sun,
and were really warm to the touch. The resulting negatives
were rather flat and heavy, and lacking in brilliancy and the
delicate gradation that is desirable.
It will thus be seen that temperature plays an import-
ant part in tank development, and success cannot be hoped
for unless careful attention is given to this detail.
Where several tanks are in use for developing a large
number of plates, enough water to fill all the tanks can be
brought to the desired temperature ; then after adding to
the tanks the stock solutions, as given in formula, fill tanks
with the tempered water to lower embossed line.
After preparing developer as directed, load plates into
the cage, with the aid of the loading block, being careful to
place the first plate glass side out, and all the others facing
it, thus bringing both outside plates glass side out, to pre-
vent scratching; remove loader, close hinged cover of cage,
and with the bail or handle thereon, lower plates slowly and
easily into the developer.
Care should be taken not to stop the plates while low-
ering into the developer.
To remove any chance air-bells, move the cage up and
224p Library of Practical Photography.
down half a dozen times after first submerging it without
bringing it above the surface of the developer. Clamp the
cover on the tank, then take the tank in both hands and
reverse rapidly three or four times. This will prevent semi-
transparent spots with blended outlines, which are some-
times caused by effervescence in developer or minute par-
ticles adhering to the surface of the plate before the film is
thoroughly saturated. Then set indicator on dial to point
when plates are to be done, thirty minutes ahead of the time
the developing begins.
During development, tank should be reversed three or
four times to agitate the developer and insure even develop-
ment, and it will be found that this agitation produces
greater brilliancy than if plates remain in one position dur-
ing the period of development.
After development is completed, the developer should
be poured off, and three or four changes of water run into
the tank to thoroughly free the negatives from developer;
then the cage may be lifted out and placed, with the plates
still in it, in the hypo bath, or the plates taken out of the
cage and fixed as usual, separately, or the fixing bath may
be poured into the tank if desired. If the cage or tank be
used for fixing, it should be washed thoroughly, and dried with
a cloth; otherwise water remaining on the metal may contain
some hypo, which will crystalize on evaporation of the
water and give trouble.
In warm weather it will be found quite advantageous
to fix the plates in the cage, as then they are thoroughly
hardened before handling with the warm hands.
Should the tank leak on being reversed, it will prob-
ably be found that the rubber lining in the cover is not in
place, or that the tank has been curved in at the top from
handling, so it does not fit snugly against the rubber band.
This can easily be remedied, and prevented with a little care.
A clean lens, always an important factor in securing
clear, bright negatives, is particularly important when using
tank method of development.
Tank Deoeloping for the Professional. 224q
As this slow development gives the value of every par-
ticle of light that reaches the plate, so it will emphasize
the fog or halation caused by a diffusion of light from a
hazy lens, and this will be more noticeable than when plates
are developed in stronger solutions.
Probably more negative troubles come from hazy lenses
than from any other one source, as there is nothing so ne-
glected by the average photographer as these delicate and
important instruments of his profession.
It is not sufficient that the outside surface be wiped off
occasionally, but it should be done regularly and carefully,
inside as well as outside, as it will be found on examination
that there is an accumulated deposit on the inner surface of
the lenses, which, acting in a modified way like a ground-
glass surface, diffuses light all over the plate during expos-
ure, and produces fog, halation, and flat, g^ay negatives.
To sum up successful tank development, even with a
perfect tank, necessitates care in the selection and character
of the chemicals used, regulation of the temperature of
plates and developer, and keeping your lenses clean.
CHAPTER XXr.
SPECIAL INSTRUCTION SUPPLIED BY THE
STANDARD AMERICAN MANUFACTURERS
FOR THE MANIPULATION OF THEIR
DIFFERENT BRANDS OF PLATES.
549. Introduction. — Believing it essential that the photo-
grapher should be competent to manipulate any of the standard
American brands of plates, it is advisable, therefore, that each
brand be given careful trial. In order to obtain the very
best results one should work each plate under all conditions, and
when trying one brand of plate do not attempt to work another
until you have mastered the particular plate you are manipula-
ting. After all the different brands have been worked, and
you are quite familiar with their manipulation, then you can
intelligently determine which is best suited for your par-
ticular work.
550. In order to supply the reader with still more valuable
information regarding any particular standard American make
of plates, we have had the different manufacturers prepare for
us special instruction, which they have compiled from the
information obtained from their numerous demonstrators,
operating in all parts of the country. This special informa-
tion covers the manipulation of all their different brands of
plates, and is supplied under their respective headings, in the
following chapters : —
II— 13 226
226 Library of Practical Photography.
PART I.
CRAMER PLATES.
Special notes treating upon the manipulation of the various
brands of Cramer flates, compiled especially for this
Library by the Cramer Dry Plate Company.
551. A resum6 of negative-making methods of manipu-
lation, and the advantages of using special brands for special
work.
552. Consider it an axiom that the perfect negative is the
result of proper lighting and normal exposure, and that such
a plate can only be ruined in the dark room by gross careless-
ness. Also that no juggling with developers will compen-
sate for carelessness in lighting or exposure. It is self-evi-
dent that if there has been no exposure there can be no devel-
opment of an image, also that if there has been insufficient
exposure or hard lighting, satisfactory results cannot be ob-
tained, though if the exposure and lighting have been within
the latitude of the plate used, skillful handling of the plate
during development will give satisfactory results.
553. Train yourself to be careful, accurate and cleanly,
and so reduce probability of error to the minimum. A dry-
plate is a very delicate and sensitive chemical product, and
should be handled so as to eliminate all danger of chemical or
light fog. When a shipment is received, store the plates on
edge, ( to avoid pressure ) in a cool dry place, away from
strong light, and free from the influence of sewer or illumina-
ting gas. When opening a package, and filling plate hold-
ers, keep well away from the dark room light (some
brands, notably the Trichromatic should be placed in the
holders without any light being used, and in a perfectly dark
room).
554. Filling Holders. — Dust the plate slowly, and thor-
oughly with a soft, wide camel's hair brush, and place in the
holder with the film side towards the slide of the holder.
special Instruction for Cramer Plates. Til
Close the holder and the plate is then ready for exposure in
the camera. The first plate in an original package is face
down, the second face up, the third face down, etc. Be sure
before leaving the dark room that no packages of plates are
open, and that all holders are closed.
555. Speed of Plates. — The Crown and the Instantane-
ous Isochromatic are the two fastest brands made, and for all
practical purposes when used under the same conditions, can
be considered as of equal speed, and either of these brands
should be used for all rapid exposures.
556. Exposure. — Correct exposure, or exposure within
the latitude of the plate is of vital importance. Time spent
in becoming familiar with your lens, plate, light conditions,
lighting of subject, etc., is well employed. We would advise
all outdoor workers, and those making interiors, to become
familiar with, and constantly use a good exposure table, or
exposure meter. Its use will enable you to be more certain of
the exposure needed under all light conditions for all subjects,
at all times of the day and year, and you will have the satis-
faction of bringing home plates that will make good printing
negatives.
557. For exposures under the skylight nothing will take
the place of experience ; money spent on a rapid lens, and
time spent in keeping that lens perfectly clean, are both well
invested. For cleaning the lens take water three ounces,
grain alcohol one ounce, nitric acid three drops. After dust-
ing the lens rub with an old clean cotton cloth wet with this
solution, and polish with a dry piece of the same cloth.
558. The light should fall on the sitter at an angle of forty-
five degrees, and except for special purposes, there should be
no violent contrasts between the lights and shadows. Illumi-
nate the shadows sufficiently to balance the lights, or cut down
the volume of light falling on the skylight side of the subject
by means of a screen so that the lights will balance the
shadows. This, and correct exposure, are the only ways to ob-
tain negatives which will please the great majority of the picture
buying public. In making white draperies do not flood them
with light if you want detail, nor on the other hand do not
228 Library of Practical Photograph}^.
keep their tone so low that there are none of those little crisp
highlights which add so much to the quality and beauty of
the negative.
559. By study and by test become familiar with the light
effects obtainable under different portions of your skylight,
bearing in mind that under an open light the nearer the sub-
ject is to the side light, the more violent the contrasts, while
further away they are less. Learn the difference in exposure
needed with the different diaphragms, and with the same dia-
phragm when making a large head and a full figure.
560. The latitude of Cramer plates is so great that if two
seconds were the normal exposure, under certain conditions,
an exposure of either one second or of four seconds would
yield a satisfactory printing negative, if properly developed.
Do not abuse the power this latitude gives, for unless you are
w^illing to vary your treatment of plates with extremes of
exposure, you will be disappointed in the results obtained.
Strive for an even quality of negatives the year round, and
the printer shall rise up and call you blessed.
561. Development of Normal Exposures. — If you
want a steady quality of negatives you must be able to repro-
duce identical conditions in your dark room every day, if you
cannot, you will not reap the reward you desire if even expo-
sures were made in the field or skylight room. Buy only the
best chemicals, keep fresh solutions made with pure water, al-
ways test the temperature of the developer by means of a
thermometer, using it at a temperature of between sixty-five
and seventy degrees Fahr., and maintain this temperature
during the whole period of development. Keep your trays,
graduates, bottles and dark room clean, provide a proper fixing
box and keep it filled with a fresh acid-fixing bath.
562. Accustom yourself to working far away from your
dark room light, and to exposing plates during development
as little as possible to its influence. Use sufficient solution to
keep the plate well covered, and continue the development
until the lights are sufficiently intense, and no longer. As
soon as a plate shows under-exposure, add to the developer an
equal quantity of water which may be somewhat warmer, so
special Instruction for Cramer Plates. 229
that there may be time for all possible detail to develop be-
fore the lights become too dense, your object being to get as
soft a printing negative as you can. Continued action of nor-
mal developer will unduly emphasize the contrasts by giving
abnormal density in the lights before all the shadow detail is
out.
563. If the plate is over-exposed, the lights and shadows
will appear simultaneously, and the negative will develop flat
without contrast, unless a sufficient quantity of a one to ten
solution of bromide of potassium is added to the developer,
either in the beginning or as soon as over-exposure is noticed,
the quantity of bromide solution to be added depending on
the degree of over-exposure.
564. A few years ago the G. Cramer Dry Plate Co. put
on the market their liquid acetone, and during this time it
has earned a well deserved place on the dark room shelf.
Acetone is a neutral liquid which replaces the alkali in devel-
oping solutions. Combined with sulphite of soda and a de-
veloping agent it makes a far more regular working developer
than any form of alkaline developer can. As no alkali is used
there is less danger of the film softening in warm weather, the
false densities common with an alkaline developer are avoided
and chemical fog from a developer which is too warm or too
strong in alkali entirely absent. Liquid acetone should not be
confounded with acetone-sulphite (a dry acid powder), which
will not answer the purpose.
565. With the pyro-acetone formula, any temperature be-
tween sixty-five and eighty degrees Fahrenheit can be used
with perfect safety. For tank development it is ideal, as the
temperature need not be watched, though of course the higher
temperatures naturally cause more rapid development.
566. With normally exposed plates, and any of our stand-
ard normal developers at seventy degrees, development should
be completed in from five to eight minutes, depending on the
factor of the developing agent used. If it is necessary to
develop longer than eight minutes, investigate the quality of
the chemicals used, the temperature of your developer and
dark room, suspecting especially the quality of your carbon-
230 Librar}) of Practical Photography.
ate of soda if using an alkaline developer, and of the quality
of your sulphite of soda if using acetone.
567. The Best Developer. — We are often asked what
is the best developer. This question can only be answered
relatively, as it depends on for what purpose the negative is
to be used. For instance it would not be advisable to use the
same developer for fast focal plane shutter-exposures, and for
the development of copies from line drawings. In the first
instance all the detail possible is wanted, and in the second,
all the contrast. Pyrogallic acid is probably used to a greater
extent than all other developing agents combined, as it can
be easily modified, which is an advantage, but only in the
hands of an experienced operator, and it should be used imme-
diately after mixing. Most other developers have better keep-
ing qualities and can be used repeatedly, but each time a
developing solution is used it not only loses some of its activ-
ity but it also takes up chemicals from the plates developed,
which will make it work slower, and with more contrast,
besides making it liable to work injuriously to the plate in
other ways. ( See note at end of Developers.)
568. The best advice that can be given is to adopt some
standard Cramer developer for regular work, become familiar
with its action under various circumstances, and stick to that
formula. When undertaking special work, use one of the
formulae recommended for that purpose, and always keep a
ten per cent, solution of bromide of potassium in your dark
room for use when needed.
569. Dry Plate Don'tS. — Don't blame the plates for fog
until you know that your camera, shutter or holders, do not
leak or reflect light, that your lens is clean, the interior of the
tube and the diaphragms dead black, that your dark room is
light tight, your developing light safe, your chemicals fresh and
pure and in proper working condition, water pure, trays clean,
developer not too warm or too strong, and that it contains
sufficient bromide of potassium to make it work clear, and
until you know that the plates have been stored on edge, in a
cool, dry place, free from fumes of illuminating or other
gases, and are not too old.
"THE UP HILL ROAD"
Study No. 12, See Page 345 Geo. H. Scheer, M. D., Sheboygan, Wis.
special Instruction for Cramer Plates. 233
570. Don't blame the plates for excessive contrast until
you know that your lighting is not too harsh, that the ex-
posure is sufficient, your lens clean, that your carbonate of
soda is of the best quality, that your developer is not too con-
centrated or too strong in carbonate of soda, and that your
other chemicals are pure and fresh.
571. Don't blame the plates for being thin and weak until
you know that you are buying pure carbonate of soda, and us-
ing a sufficient quantity of it. That your hydrometer is correct,
that you are not over-exposing and under-developing, that
you are not lighting too flatly, that you are using your de-
veloper strong enough and warm enough, and using enough
bromide of potassium to keep it working clear.
572. Don't blame the plates for lack of speed or detail un-
til you know that your skylight and lens are clean, that your
shutter works as it should, that your diaphragm is not too
small, that your lighting is not too weak or too harsh, that
your carbonate of soda is all right, and that your hydrometer
is correct, and also that your dark room and developer are
not too cold.
573. Don't blame the plates for being yellow and stained
until you know that your sulphite of soda is pure, fresh and
strong enough, that your hypo bath is fresh and slightly acid,
that the developer is fresh and cool, and all the chemicals
pure and thoroughly dissolved.
574. Don't blame the plates for softening and frilling un-
til you know that you are using a fresh acid fixing and harden-
ing bath, that the plates have been left in the bath until the plate
is hardened way through, that the temperature of the devel-
oper and fixing bath were not too warm, and that too much
carbonate of soda was not used in the developer.
575. Don't blame the plates for insensitive spots, streaks
or blotches until you are sure that your developer is not too
old or too dilute, particularly when you are using hydro-
quinone.
576. Don't blame the plates for spots and lines until you
know they are not caused by air-bells, dust, glass splinters
(from developing several plates at once), scum on developer.
234 Librar}) of Practical Photography.
scale from water pipes, bottles or trays, dry pyro or undis-
solved chemicals, iron scale in water, dirt in camera or hold-
ers, water containing organic matter, or a dirty or too stiff
dusting brush.
577. Standard Formulse for Cramer Plates : —
Pyro-Acktone Developer.
Works quick and uniform, without frilling; can be used in warm
climates without ice, and does not stain the hands.
A. — Pure water 16 ounces 640 c.c.m.
Oxalic Acid 12 grains i gram
Pyrogallic Acid i ounce 40 grams
B. — Pure water. . 20 ounces 600 c.c.m.
Cramer's Dry Sulphite Soda. 2 ounces 60 grams
(Or 20 ounces Sulphite Soda solution 48 degrees hydrom-
eter test.)
Cramer's (Liquid) Acetone.. 4 ounces 120 c.c.m.
For use take:
A I ounce 30 c.c.m.
B 2 ounces 60 c.c.m.
Water 8 to 12 ounces 240 to 360 c.c.m.
For Double Coated plates use A i ounce, B 2 ounces, water 18
ounces.
For Tank Development use A i ounce, B 2 ounces, water 30 ounces.
578. Pyro Developer.
A. — Pure water 16 ounces 640 c.c.m.
Oxalic Acid 12 grains i gram
Pyrogallic Acid i ounce 40 grams
B. — Pure water 16 ounces 640 c.c.m.
Cramer's Dry Sulphite Soda. 2 ounces 80 grams
(Which will test 60 degrees by hydrometer.)
If negatives are too yellow use more sulphite, if too gray use less.
C. — Pure water 24 ounces 720 c.c.m.
Cramer's Dry Carbonate Soda 2 ounces 60 grams
(Which will test 40 degrees by hydrometer.)
Special Instruction for Cramer Plates. 235
For softer effects use less Carbonate (weaker solution).
Mix for immediate use in the following proportions.
A I ounce A i part
B I ounce B i part
C I ounce C i part
* Water 15 ounces * Water 15 parts
♦The quantity of water may be varied from 10 to 20 ounces, 10
ounces for more contrast and density, 20 ounces for less.
579. Ortol Developer.
In One Solution :
Pure water 60 ounces 1800 c.c.m.
Ortol 300 grains 20 grams
Bromide of Potassium 15 grains i gram
Cramer's Dry Sulphite Soda. . 3 ounces 90 grams
♦Cramer's Dry Carbonate Soda i^ ounces 45 grams
For use mix i part of this stock solution with water i to 2 parts for
winter use : water 2 to 4 parts for summer use, according to density
desired.
-^ - ♦q ounces Cramer's (Liquid) Acetone 270 c.c.m.
can be substituted for i)^ ounces dry carbonate soda.
580. Hydrociuinone-Metol Developer.
A . — Pure water 25 ounces 750 c.c.m.
Metol 60 grains 4 grams
Hydroquinone 60 grains 4 grams
Cramer's Dry Sulphite Soda, i ounce 30 grams
B*. — Pure water 25 ounces 750 c.c.m.
Cramer's Dry Carbonate Soda '%. ounce 15 grams
(Which will test 10 degrees by hydrometer.)
For use mix equal parts A and B.
* Solution B can be replaced by an equal quantity of diluted Ace-
tone I part Cramer's (Liquid) Acetone. Water 20 parts.
Note. — With fresh developer it may be necessary to add to each
ounce I drop of a i to 10 solution of bromide of potassium, to make it
work clear. This developer should not be used too old or too dilute
or it is liable to produce peculiar streaks and blotches.
236 Library of Practical Photography.
581. HYDROQ.UINONE-E1KONOGKN Developer.
A. — Pure hot water 60 ounces 1800 c.c.m.
Eikonogen i ounce 30 grams
Hydroquinone }^ ounce 15 grams
Cramer's Dry Sulphite Soda. 2 ounces 60 grams
B*. — Pure water 60 ounces 1800 c.c.m.
Cramer's Dry Carbonate Soda 5 ounces 150 grams
(Which will test 40 degrees by hydrometer.)
For use take: A 3 parts. B* i part.
•Solution B can be replaced by a mixture of Cramer's (Liquid)
Acetone i part, water 10 parts. A few drops of a i to 10 solution of
Bromide of Potassium should be added if the developer is quite fresh to
make it work clear. Combinations of Eikonogen and Hydroquinone
should not be used too old or too dilute as they are liable to produce
peculiar streaks and blotches on the negative.
582. Pyro-Metol Developer.
A. — Pure water 30 ounces 600 c.c.m.
Metol I ounce 20 grams
Oxalic Acid 24 grains i gram
Pyrogallic Acid }/£ ounce 10 grams
B. — Pure water 30 ounces 600 c.c.m.
Cramer's Dry Carbonate Soda 4 ounces 80 grams 3
(Which will test 64 degrees by hydrometer.) j
C. — Pure water 30 ounces 600 c.c.m.
Cramer's Dry Carbonate Soda 4 ounces 80 grams
(Which will test 64 degrees by hydrometer.)
For use take :
)^ ounce A 10 c.c.m.
% ounce B 10 c.c.m.
J^ ounce C 10 c.c.m.
10 to 15 ounces water. . . 200 to 300 c.c.m.
According to intensity desired.
A, B and C may be mixed together and keep well in one solutioi
which should be diluted for use with from 6 to 10 parts of water.
special Instruction for Cramer Plates. 237
583. Pyro-Metol with Acetone.
Substitute for B and C the following:
Pure water 60 ounces 1200 c.c.m.
Cramer's Dry Sulphite Soda. 6 ounces 120 grams
Cramer's Liquid Acetone. .. . 6 ounces 120 c.c.m.
For use take :
}4 ounce A 15 c.c.m.
I ounce B 30 c.c.m.
10 ounces water 300 c.c.m.
584. Developer for Transparencies.
(Lantern Slides.)
Hydroquinone and Pyrocatechin.
A. — Pure water 32 ounces 960 c.c.m.
Cramer's Dry Sulphite Soda. 6 ounces 180 grams
Pyrocatechin 240 grains 16 grams
Hydroquinone 240 grains 16 grams
Bromide of Potassium 120 grains 8 grams
B. — Water 32 ounces 960 c.c.m.
Caustic Potash 240 grains 16 grams
For use mix equal parts A and B.
Solution B can be replaced by :
Water 20 ounces 600 c.c.m.
Cramer's (Liquid) Acetone. . 12 ounces 360 c.c.m.
585. Contrast Developer.
For developing over-exposed plates.
Also useful as an addition to normal developer in case it does not
work with sufficient brilliancy for which purpose the addition of a few
drops per ounce is sufficient.
Pure water 30 ounces 1500 c.c.m.
Cramer's Dry Sulphite Soda, i ounce 50 grams
(Which will test 16 degrees by hydrometer.)
Edinol, Glycin or Hydroquinone loo grains 10 grams
Bromide of Potassium 20 grains 2 grams
Carbonate of Potassium }4 ounce 25 grams
Use full strength. This solution can be used repeatedly. As soon
as a plate shows over-exposure in the normal developer rinse and place
238 Library of Practical Photography.
in the dish containing the contrast developer and develop until sufS-
ciently intense.
586. Developer for Line Work.
(Black and White.)
Pure water 30 ounces 900 c.c.m.
Cramer's Dry Sulphite Soda. 2 ounces 60 grams
(Which will test 32 degrees by hydrometer.)
Edinol, Glycin or Hydroquinone 150 grains 10 grams
Bromide of Potassium 100 grains 7 grams
Carbonate of Potassium 2}^ ounces 75 grams
(Use full strength.)
This developer with Cramer Contrast Plates produces negatives of
great intensity and absolute clearness, desirable for copies of pencil
sketches, pen drawings, line work, etc.
587. Developers for X-Ray Plates.
Eikonogen- Hydroquinone Developer.
A. — Pure hot water 30 ounces 900 c.c.m.
Eikonogen 3^ ounce 7 grams
Hydroquinone % ounce 15 grams
Cramer's Dry Sulphite Soda, i ounce 30 grams
Bromide of Potassium 15 grains i gram
B. — Water 10 ounces 300 c.c.m.
Cramer's Dry Sulphite Soda, i ounce 30 grams
For use take :
6 ounces A 150 c.c.m.
2 ounces B 50 c.c.m.
A and B can be mixed together and used as one solution.
588. Pyro-Acetone for X-Ray Plates.
(Very Fine.)
Use the regular A and B Pyro-Acetone solutions taking :
1 ounce A 30 c.c.m.
4 ounces B 120 c.c.m.
2 ounces water 60 c.c.m.
Adding thereto 2 to 3 drams (8 to 10 c.c.m.) of a 10 per cent, solu-
tion of bromide of potassium.
special Instruction for Cramer Plates. 239
589. Fixing.
Rinse developed plates thoroughly to avoid carrying developer
into the fixing bath and place in the following :
Acid-Fixing and Hardening Bath.
A. — Water (i gallon) 128 ounces 4 litres
Hypo-Sulphite of Soda 32 ounces \ kilo
(Which will test about 80 degrees by hydrometer.)
B. — (See note below.) Water 32 ounces i litre
Cramer's Dry Sulphite Soda. 3 ounces 90 grams
(Which will test 45 degrees by hydrometer.)
Sulphuric Acid C. P % ounce 15 c.c.m.
Powdered Chrome Alum.... 2 ounces 60 grams
Note. — Be sure to mix solution B exactly in given proportion
and rotation. Always pour B into A while stirring well. If this is not
done precipitation will take place.
During the cold season one-half the quantity of solution B is suffi-
cient for full quantity of solution A.
B can also be prepared as follows :
Water 32 ounces i litre
Potassium Meta bi-sulphite. . 3 ounces 90 grams
Powdered Chrome Alum. ... 2 ounces 60 grams
This bath remains clear after frequent use, does not discolor the
negatives, and hardens the film to such a degree that the negatives can
be washed in warm water and dried by artificial heat if necessary.
They should be left in the bath ten to twenty minutes after the bromide
of silver appears to have been dissolved, to insure permanency, freedom
from stain, and perfect hardening.
If the bath becomes exhausted by continued use, replace it by a
new one.
Plain Fixing Bath.
Water 32 ounces i litre
Hypo-Sulphite of Soda 8 ounces 250 grams
(Which will test about 80 degrees by hydrometer.)
Do not use the bath when it is discolored, it must be made fresh
each day.
590. Tank Development. — Or stand development, is
constantly growing in popularity, due to its simplicity and the
even quality of its results. There are several precautions vrhich
240 Library of Practical Photography.
must be observed with the tank method to be used successfully.
The tank should be used for no other purpose. The grooves
may be wide enough so that two plates (placed back to back),
can be put in each groove, and the plates should not come
within one-half inch of the bottom of the tank.
591. A tank of hard rubber provided with a light tight
cover is preferable; metal tanks, unless made of copper or
brass and heavily nickel plated, should be avoided.
592. When any alkaline developer is used the temperature
should be fifty-five degrees Fahrenheit, and never allowed to
rise higher than sixty degrees Fahrenheit during the time of
development. Always test temperature with a thermometer,
as a temperature above sixty degrees is liable to cause uneven
development, stain and fog.
593. When using Cramer's (Liquid), Acetone, tempera-
tures up to seventy degrees can be used with perfect safety, as
this form of developer is not alkaline. The developer should
be thoroughly mixed before putting the plates in the solution.
Move each plate up and down quickly several times to break
air-bells, and after the plates have been in the tank about five
or ten minutes, reverse their position, putting the top of the
plate where the bottom was to insure even development, and
to avoid streaks. When putting plates into the tank be sure
that your hands are free from other chemicals.
594. Negatives made of subjects against white grounds
may need finishing by tray development in a strong concen-
trated developer containing a heavy dose of a ten per cent, solu-
tion of bromide of potassium.
595. There is a point beyond which the developer cannot
safely be diluted without causing peculiar streaks and blotches
(see note A at end of Developers), stain and fog, due to the
solution decomposing before development is complete.
After development, the tank should be thoroughly cleaned
to prevent stain.
596. Tank Developers. — Any of the Cramer standard
alkaline developers can be used for tank developers, by adding
to the tray developer made up according to formula given
in this article, two to three times its bulk of water, so that it
special Instruction for Cramer Plates. 241
takes about one-half-hour to develop at a temperature of fifty-
five degrees Fahr. Cramer's pyro-acetone developer, as given
in this article, can be used by taking one ounce of A, two
ounces of ^, and thirty ounces of water.
597. Pvro-Mktol-Acetone Developer for Tray or
Tank Developer.
A. — Water 60 ounces 2700 c.c.m,
Metol I ounce 45 grams
Citric Acid 10 grains i gram
Pyrogallic Acid i ounce 45 grams
Cramer's Dry Sulphite Soda 4 ounces 180 grams
jB. — Water 60 ounces 2700 c.c.m.
Cramer's ( Liquid ) Acetone. 6 ounces 270 c.c.m.
For use in tank take: For use in tray take:
15 ounces A i ounce A
15 ounces B i ounce B
200 ounces water 5 ounces water
We do not give the time required to develop plates with
any of these formulae, as some users might consider that the
time given was a fixed factor, when it depends entirely upon
each user's idea of what is the proper intensity. When the
time is once settled, however, it can be depended on to give
the same intensity with the same temperature and strength of
developer, provided the exposures are the same.
598. Peculiar streaks and blotches in the shape of brush
marks, finger marks and insensitive spots, appearing as though
the plate had been scrubbed with a dirty or greasy brush, or
improperly cleaned, are caused by the uneven action of the
developer, if it is too old or too much diluted. This trouble
is more liable to occur if hydroquinone is used in connection
with eikonogen or metol ; and can be prevented by using the
developer more concentrated or by a radical change to a dif-
ferent developer.
599„ It is hard for a user of dry plates to believe that this
trouble is not the fault of the plate, as its appearance and dis-
appearance is erratic, but the most skeptical can convince
themselves by making up a fresh and stronger developer from
chemicals of known purity, and which have not deteriorated
242 Library of Practical Photography^.
by long standing. Then develop more of the same lot of
plates, none of which will show any markings.
600. Different Brands of Cramer Plates and Their
Uses. — Cramer Crown Plates are the most rapid plates
made. They work with great softness and shadow detail,
which qualities especially recommend them for focal plane
shutter-exposures, hand cameras, and all instantaneous work.
For large negatives and groups in the studio, and for expo-
sures in a poor light or with slow lenses, they should always
be used.
601. Cramer Banner X Plates. — Are very rapid
with great latitude, giving quick printing negatives full of
detail, which produce brilliant prints with perfect gradation
from the highest lights to the deepest shadows. They are
the most popular plates for general use in portrait photog-
raphy.
602. Cramer Blue Label Plates. — Made especially for
those who prefer plates with more vigor and slightly less
speed than the above.
603. Cramer Anchor Plates, of less speed, giving
negatives of great clearness and density. Mostly used for
commercial work and copies.
604. These four brands can all be handled under ordinary
safe dark room conditions with any of the standard Cramer
developing formulas.
605. Cramer Isochromatic Plates. — The universal use
of the Isochromatic plates would be of great help in the uni-
versal production of better photographs, as they will always
give as good results as can be obtained with ordinary plates,
and in the great majority of cases far better results. Thou-
sands of photographers do not realize what Isochromatic plates
will do for them, or believe that they are more difficult to ma-
nipulate. A fair trial will show what Isochromatic plates will
accomplish and prove that they are no more difficult to handle
than the ordinary plates.
606. Photographers at present are not concerned with the
reproduction of color as color, but with the reproduction of
color as black, white, and the intermediate tones of gray, and
special Instruction for Cramer Plates. 243
as the ordinary dry plate is most sensitive to the ultra violet
rays, (these rays being totally invisible to the eye), very sen-
sitive to violet and blue, while almost totally insensitive to
green, yellow, orange and red, its reproductions of color are
outrageously false, and only put up with at all because we are
accustomed to such false renderings.
607. The Isochromatic plates being less sensitive to the
ultra violet, violet and blue rays, and more sensitive to green,
yellow and orange, give far more truthful reproductions of
color, even when used without a screen or ray filter, while a
very pale ray filter will entirely eliminate the ultra violet rays,
and subdue the action of the violet and blue, giving time for
full action of the orange, yellow and green. The use of a ray
filter on ordinary plates is of no benefit, as these plates are
not color sensitive.
608. Portrait photographers are particularly slow to realize
the value of Isochromatic plates in studio work, because they
believe there is no advantage in their use without a screen,
while the doubled or trebled exposure needed with even a
weak screen would make their use impracticable. There are,
however, marked advantages in studio use, notably when
photographing blondes, blue eyes, colored costumes, and as a
help to the more truthful rendering of complexions, due to
their sensitiveness to yellow and orange.
609. Their advantages in the field are so great, that if
once compared with ordinary plates they will always be used,
for they give detail when detail was lacking in foliage and
foreground, clouds that will print without reducing or dodg-
ing, show distant mountains, invisible on ordinary plates and
make prints that show nature's colors translated into their
true monochrome values.
610. For commercial work, interior work, and home por-
traiture the use of Isochromatic plates is indispensable. They
show grain in wood and design in colored fabrics, detail in
frescoes and colored decorations, and are particularly adapted
for copying paintings and showing differences in the
values of colored costumes and backgrounds in at home
portraiture.
II — 14
244 Librar}) of Practical Photography.
6ii. The demand for Cramer's Isochromatic plates is
steadily growing, due to the increasing knowledge of their
advantages. They can be handled in the same way as ordi-
nary plates, except that holders should be filled and develop-
ing done further away from the dark room light, unless it is
sufficiently subdued. Develop the Isochromatic with any
standard formula for Cramer plates.
612. Screens or Ray Filters. — For use with Isochro-
matic plates for best results, should be adjusted to the
plate, and we are now preparing to place on the market
screens spectroscopically corrected for these plates. The
increase of time needed when a screen is used depends on the
strength and quality of color used in the screen, and varies
from simply doubling of the time used without a screen up to
twenty times as much. Blue prints can be beautifully copied
by using an Isochromatic plate, and a deep orange screen
which will give a negative ( if properly timed) showing
white lines on a black ground instead of the weak, flat nega-
tive given when ordinary plates are used.
613. Isochromatic plates are made in three speeds, instan-
taneous, medium and slow.
614. Instantaneous Isochromatic for portraits and all work
where a rapid exposure is required. These plates give better
color values without the use of a yellow screen than any other
plate of the same rapidity. They are fully isochromatic when
used with a pale yellow ray filter, which requires only a trifle
longer exposure. On account of their high sensitiveness to
yellow and artificial light, they are the best plates for
flash-light exposures.
615. Medium Isochromatic Used Extensively for
General Commercial Photography. — In interiors the de-
tail in delicate frescoes and colored decorations, which does not
show at all when photographed with regular plates, is brought
out clearly.
(i\(). By using these plates in landscape work the different
shades of foliage, and the values of the sky and clouds are
given far better, while distant objects, even in hazy atmos-
phere, show more distinctly.
special Instruction for Cramer Plates. 245
617. Ray Filters or Color Scrbens are required only
when the full isochromatic effect is wanted.
618. Slow Isochromatic. — This plate is the only plate
made that is fully sensitive to yellow and orange color without
the use of a yellow screen. It is especially adapted for copy-
ing paintings, and will be found invaluable in commercial
work, bringing out the grain of wood and design of fabrics,
and giving definition that is very desirable in work for trade
catalogues. Also excellent for cloud effects.
619. Cramer's Trichromatic Plates. — These plates are
sensitive to all colors, including red, and while they do not
possess the exceedingly high red and green sensitiveness which
characterizes the Paniso plate are yet eminently suited for
the three-color (indirect) process when used with their proper
filters. For landscape photography in combination with the
light ISOS II ray filter their use results in effects which are
immeasurably superior to those obtained on any other isochro-
matic or orthochromatic plate. Having a greater extent of
sensitiveness (towards the red) than the Instantaneous Isochro-
matic their superiority of reproduction in all cases concerned
with color is obvious, when we consider that this superiority
is simply proportional to the increase or color sensitiveness.
620. Three-color work requires three negatives, one made
through a blue or purple screen, one through a green, and one
through a red color screen. The adjustment of the screens to
the plate governs the amount of stopping out and re-etching
needed on the printing blocks; poor screens give blocks that
need much of this work, while blocks made from plates
exposed through spectroscopically adjusted screens require
but little re-etching.
62 1 . Trichromatic plates can also be used with advantage
in out-of-door work, with an adjusted screen, and will be
found to give exquisite tone values when properly used.
622. As this plate is extremely sensitive to all colors, it
should be handled both before and after exposure in the dark,
or only examined by means of the Cramer Safe-light which
transmits only the extreme red of the spectrum, and to which
these plates are not sensitive.
623. Develop Trichromatic plates with any standard Cra-
mer formulae, using the time and temperature method. Rinse
246 Library) of Practical Photography.
well and leave the negative in an acid-fixing and hardening
bath until entirely fixed.
624. Cramer'sDouble-Coatkd Non-Halation Plates.
— First coated with a slow, and for a second time with a rapid
emulsion. Specially made to prevent halation, and hence
recommended for photographing interiors in ivhich strong"
light ejitering through the tvindoivs has to be contended with,
and for landscapes , 'white draperies and all objects where
there exists a strong contrast between light and shade.
625. Use a rather dilute developer for double-coated plates,
so that the development can be prolonged sufficiently to affect
the lower film, which will take about double the usual time.
Rinse for two minutes, and fix in acid-fixing and hardening
bath, leaving them in the bath until entirely fixed, which,
owing to the thickness of the film, will take more than double
the time of a single coated plate. If the plate is taken from
the bath before it is fixed, stain will ensue. Final washing
must be thorough.
626. Care should be taken that the temperature of the
developer, water used for rinsing, and fixing bath be the same,
and that the acid-fixing and hardening bath be fresh and prop-
erly made. These precautions will obviate any danger of the
upper and lower films separating.
627. The Double-Coated are made in the following brands :
— Crown, Banner X and Isochromatic Instantaneous, Medium
and Slow.
Cramer Stripping Plates. — Made in Crown, Banner
X, Isochromatic or Contrast Brands.
For photo-mechanical work, and all cases where it is nec-
essary to use a reversed negative or transfer a negative film
from its original glass to another support.
628. Directions for Use. — The manner of manipulating
these plates differs but little from that of the ordinary dry
plate, the development, fixing, hardening and washing being
the same. But the temperature of the developer should not
be higher than sixty or sixty-five degrees Fahrenheit, and a
fresh cool acid-fixing and hardening bath should be used.
Great care, however, should be taken to prevent an injury to
special Instruction for Cramer Plates, 247
the surface of the film during these operations, as the intro-
duction of fluids between the glass and film would injure the
latter. After the final washing the surface of the plate
should be flowed with a mixture composed of one part glyc-
erine and thirty parts water. Cut a piece of gelatine tissue,
somewhat larger than the plate, soak this in this solution, and
bring it in contact with the wet surface of the film. Air-bells
between the film and tissue should be carefully expelled by the
use of a soft damp sponge, or a squeegee. The over-lapping
ends should now be pasted to the back of the negative with
stiff starch paste, and the whole placed in the rack to dry. It
may then be flowed with plain collodion. To strip the film,
cut through it all around the edge of the plate about one-fourth
inch in, and remove it with a steady pull. Any stoppage
during this operation will cause marks on the negative and
should be avoided. The stripped negatives should be pre-
served between the leaves of a book. They can be printed
from either side.
629. For transferring to another sheet of glass harden the
fixed and washed negative for ten minutes in a bath composed
of Formalin one ounce, water ten ounces, glycerine one-half
ounce, then rinse free from all greasy appearance and dry.
Cut through edges of film, and remove from the glass as di-
rected above. Then place the film in a warm solution (about
ninety degrees Fahrenheit), composed of hard gelatine one
ounce, swelled and then dissolved in fifteen ounces of warm
water, with the addition of one ounce of glycerine, until the
film is limp, then transfer to the clean sheet of glass and
gently remove all air-bells with a soft sponge or squeegee,
working from the center of the film.
630. Cramer X-Ray Plates, are specially made by the
Cramer Co. for making X-Ray negatives.
631. While any ordinary plate is of course aff'ected by the
X-Rays, yet they do not possess those properties that have
built up the reputation of the Cramer X-Ray plate among
experts, and X-Ray specialists.
632. X-Ray plates should be kept in a lead lined case to pro-
tect them from the influence of the rays. Nor should plates
248 Library of Practical Photography.
before or after exposure be left for more than a short time in
the envelopes, as prolonged contact with the paper will in-
jure or spoil the plate. When placing plates in the envel-
opes keep well away from the dark room light, and put the
film side of the plate towards the face of the black envelope,
and insert the black envelope flap end down, with the face of
the black envelope towards the face of the yellow envelope.
Even when in the double envelopes the plates should not be
exposed to the influence of strong daylight, but protected by
a paste board box, if they are to be carried out of doors, to
avoid danger of fogging. Never take a plate near an X-
Ray machine when the tube is turned on or it will fog. It
is impossible to give any directions for duration of exposure
needed, this depending on whether a coil or a static machine
is used, and their size and power, as well as on the kind and
quality of tube used. Generally speaking, static machines
have been superseded by coils on account of the former's lack
of power, they only being suitable for light work like the ex-
tremities. Most workers believe that a tube of rather low
vacuum and high penetrating power makes better negatives
than one of high vacuum and high penetrating power, as the
latter penetrates the bones so much that there is not sufficient
contrast in the negative. In making X-Ray exposures, err
on the side of over, rather than under-exposure, and for de-
velopment use a strong concentrated developer with a good
dose of bromide of potassium, and carry development as far
as possible (after-reduction is easy if necessary). Either of
the X-Ray developers given among formulae in this article
will give good results, the most desirable negative being
one of great intensity in the easily penetrated parts, good de-
tail in the tissues with plenty of contrast between them and
the bones.
633. Fix the plates in a fresh acid-fixing and hardening
bath, leaving them in this bath long enough to harden the film
way through.
Warning : — Operators should not expose their hands or
bodies to the influence of the rays for repeated exposures will
result in burns which, as far as known, cannot be healed.
"A TOKIO WATERWAY"
Study No. 13, See Page 345 Tokio, Japan Wm. H. Phillips,
Liverpool, Ohio
special Instruction for Cramer Plates. 251
634. Cramer Contrast Plates. — For copying drawings,
engravings, photographs etc., for half-tone plates (Line screen
or Process Work).
635. For developing use any of the normal developers, or
the Contrast Developer. The two may be mixed in propor-
tions to suit or used in two trays alternately. For producing
the greatest contrast, with absolutely clear shadows (black
and white), use the developer for line work given among the
developers.
636. Cramer's Transparency Plates, on Clear
OR Ground Glass. — Coated with a specially prepared slow
emulsion, producing the very finest transparencies or positives
on glass. Develop with Transparency developer given among
the developers.
637. Cramer Lantern Slide Plates. — On first quality,
thin crystal glass, producing rich, brilliant slides with abso-
lutely clear glass in the highlights.
638. Lantern Slides can be made from negatives by copy-
ing in the camera or by contact. The time of exposure when
printing by contact depends on the source of light and the dis-
tance of the light from the negative. Under a negative of
ordinary intensity at a distance of three feet from the light of
an ordinary fish-tail burner, or an incandescent light, a few
seconds' exposure will be sufficient. The proper time required
can easily be ascertained by a few trials. If the negative is
very dense the distance from the light should be shorter, if the
negative is thin the distance between the negative and the
light should be increased.
639. For developing use Transparency developer, given
among the developers.
640. Comparative Speed of Cramer Plates. — (Ap-
proximately.)— If the Crown requires i unit of time. Banner
X will require 1^ units. Blue Label will require i^ units, An-
chor will require 2^ units, Instantaneous Isochromatic will re-
quire I unit. Medium Isochromatic will require i f to 2 units.
Slow Isochromatic will require 8 to 10 units, Contrast will re-
quire 10 to 15 units. Transparency and Lantern Slide 10 to 15
unite, Double coats according to brand.
1909 SUPPLEMENT.
641. Panchromatic (Bathed) Plates. — It has long been
known that the introduction of dye stuffs to the sensitive
emulsion during the process of manufacture does not give
as high a color sensitive effect as may be obtained by bath-
ing the finished plate in a dye bath. The great uncertainty,
however, dependent upon this mode of treatment, and the
necessary skill and apparatus required for successful re-
sults, has precluded its adoption save by isolated indi-
viduals. The Cramer Company have recently installed
complete apparatus for the production of plates and are
supplying plates sensitized for any region of the spectrum.
Cramer's "Paniso" (Bathed) Plate. — This plate is sen-
sitive to the entire range of the spectrum from the extreme
infra-red to the extreme ultra-violet and must be handled
and developed in total darkness. That total darkness is a
necessity, is simply a tribute to the color sensitiveness of
the plate.
The Paniso is primarily suited to the needs of scien-
tific and three-color workers, but they are also particularly
well adapted, when used with their proper ray filter, for
the commercial photographer, or for anyone who is en-
gaged in the photographing of colored objects.
By their use deep reds and greens which are other-
wise either unattainable, or imperfectly rendered, are rep-
resented with values absolutely unapproached by any
other plate. For landscape photography by advanced
workers their use with an extremely light ray filter gives
absolutely correct color values.
As has already been stated, the Cramer Company
prepare (on order) plates sensitized for any spectral
color, but in the use of all bathed plates due attention
must be paid to the fact that plates so prepared have but
limited keeping quality, so should not be stocked in quan-
tities. Such plates are not handled by dealers, but must be
ordered direct from the factory.
(251a)
special Instruction for Cramer Plates. 25\b
The introduction of the Paniso among scientists
reaped an instantaneous success, for in the hands of Pro-
fessor Hale of the Carnegie Solar Observatory, were ob-
tained results which shed revolutionary light upon the solar
theories.
In the exacting field of photo-micrography, these
bathed plates stand for the achievement of the highest
possible results. No object is so stained that it cannot be
reproduced with full detail.
Color Screens (or Ray-Filters). — To appreciate thor-
oughly the use and value of a ray filter in conjunction
with an isochromatic plate it is necessary to give some
consideration to the imperfections of the ordinary photog-
raphic plate.
All ordinary photographic plates are color blind and
therefore represent wrongly the relative brightness of dif-
ferent colors, a dark blue photographing as very light,
while a bright yellow is copied as being very dark. Or sup-
posing one is exposing upon a green field in which are
clusters of bright yellow flowers, the flowers would be in-
visible on the finished print (because the plate is not sen-
sitive to yellow), and the whole effect of the scene would
be lost.
An isochromatic plate is a photographic plate which
has (by changes in manufacture) been made sensitive to the
yellow and green. With such a plate a patch of bright yel-
low is represented as being of about equal brightness with
a patch of green or blue, and this is as far as the sensitive
plate is capable of.
Now in order to obtain a record of the yellow flowers
as being brighter than the green grass, it is necessary to
make use of a ray filter which is used in front of or behind
the lens, and whose purpose is to dim down or hold back
the blue and violet rays to which the plate is too sensitive.
When any ray-filter is made use of it slows down the work-
ing speed of the plate, because it has filtered out some of the
light rays which are falling upon its surface, therefore more
time must be given to the exposure.
25 1 c Library of Practical Photography.
While any color filter will give effects of a kind, yet
for choice results the filter must be adjusted to the plate;
it naturally follows that the plate maker is in the best
position to determine this point. It however, often hap-
pens that owing to movement or other causes, it is not
possible to give any extended lengthening of the exposure,
and retain a sharp picture, and in such cases it is decidedly
desirable to sacrifice some of the exactitude of color render-
ing, and yet obtain superior results. In such cases it would
be better to have the view only, say, half corrected, or even
less. Again : in the the photographing of a landscape illum-
inated by the setting sun, it is obviously not necessary to
use so deeply colored a ray-filter as at midday, because the
view is already colored yellow.
For these reasons the Iso filters are made in three dif-
ferent depths of color requiring respectively double, three
times, and five times the exposure necessary for an un-
screen plate. They are made of two plates of the very high-
est grade of optical glass, which have been reground and
polished plane, and cemented between them a thin film of
dyed gelatine which has been spectrographically adjusted.
These filters are made of such exactitude that each or all
of the separate shades test precisely identical. They are
intended for use behind the lens, fittings being provided
with each.
The reason why a ray-filter requires to be adjusted to
the plate with which it is intended to be used, is because
various plate manufacturers make "iso" or "orthochromatic"
plates which are as variously color sensitive as are the
number of "brands," consequently the blue and violet re-
quire filtering out (or holding back) to a greater or less
extent, depending upon the ability of the manufacturer to
increase his color sensitiveness in proportion to the action
in the blue-violet. The higher the sensitiveness to other
colors the quicker the photographic action, and the less
dense is the ray-filter.
The Cramer Instantaneous Isochromatic plates have
special Instruction for Cramer Plates, 25\d
the highest action in the yellow green of any "iso" or
"orthochromatic" plate manufactured; therefore our ray-
filters require less time than any other.
While the Isos filters are specially adjusted for the
Cramer plates, they will perform well with any other "Iso"
or "orthochromatic" plate, as they are fitted for work with
the highest type of "iso" plate.
Isos Film Filters. — For the convenience of those who
desire to test for themselves the value of the Isos Ray-filters
at a minimum expenditure, we have also made them up in
thin gelatine film. This film corresponds to a definite meas-
ured amount of dye stuffs dissolved in a definite weighed
amount of gelatin, flowed over a definite measured area.
These films are guaranteed to be exact spectroscopic dupli-
cates of the permanent cemented filters and are intended
for use in front of or behind the diaphragm between the
lenses. If an iris diaphragm, simply unscrew the front or
back lens and drop in the film (cut to size with a scissors)
or if the diaphragms are of the Waterhouse type, then slip
it in with the stop. Of course these film-filters are much
more easily injured than the permanent glass cemented
filters and consequently require to be handled with greater
care.
The Isos ray-filters are the most rapid adjusted filters
manufactured: the Isos III gives correction which is not
obtained by any other filter under 9 times exposure.
Isos I (Light) for objects in motion, studio portrait
work, etc., and where but one-half correc-
tion is desired. Exposure equals double the
time necessary for unscreened plate.
Isos II (Medium) for objects and views where more
time is allowable, giving about two-thirds
full correction. Exposure equals three times.
Isos III (Dark) for copying paintings, blue prints,
etc., and for use in landscape, portrait and
genre photography. Exposure equals five
times.
25 1 c Library of Practical Photography.
With the Trichromatic plate we do not recommend
Isos III for general work : Isos II gives full correction. For
the copying of blue prints however, the Trichromatic and
Isos III gives positive results.
Ray-Filters for Photomicroscopists and Commercial
Photographers. — Color screens of this type form a class by
themselves. For the commercial photographer who is en-
gaged in the copying of numberless colored articles, furni-
ture, etc., or for the copying of colored labels, writings, and
the thousand and one things which go to make up the ordi-
nary line of work, their use is simply invaluable. This class
of ray-filters are known as "Contrast Filters" and by their
aid the worker can subdue or eccentuate whatsoever color
or line he desires. Objects of any color can be represented
either with full detail, or full contrast, (either as black or
white) according as the filters are used. The Cramer Com-
pany stand ready to supply any information on this point
which may be required,
Photomicro graphic ray-filters are a still different type of
article, and represent a color screen which can not be made
use of as in ordinary photography. They are simply in-
tended for use between the illuminant and the object and
for such purpose do not require to be made on optical glass.
Their colors are spectroscopically adjusted to the transmis-
sion (or absorption) of the stains most commonly in use
by micrographic workers. By their use the microscopist is
enabled to obtain results in the photography of stained sec-
tions, and other preparations which would be impossible
except by making use of complicated and expensive spectral
light apparatus.
Monochromatic Color Filters for the use of spectro-
scopists, physicists, etc, are also manufactured by the
Cramer Company, who have installed a laboratory equip-
ment solely for that purpose, and who are prepared to fur-
nish color filters of any absorption or transmission for any
purpose, and upon surfaces of any degree of accuracy re-
quired up to a measured error of 1/80,000 of an inch.
special Inslruciion for Cramer Plates, 251/
Tri-color Filters. — There is perhaps no class of color
filters in which so great a variance prevails as in filters in-
tended for three-color work. Almost every manufacturer of
photographic specialties has at some time or another during
the course of his business, produced a set of so-called "ad-
justed tri-color filters" which, however, are absolutely
worthless when it comes to fulfilling theoretical or practical
conditions. There are two causes to blame for this condi-
tion : First, plate errors, viz., insensitive color regions ; and
second, imperfect filter absorption, viz., lack of theoretical
knowledge. The first of these imperfections has been over-
come by the even sensitiveness of the Cramer Paniso plate
and the second by placing such work under the direction of
an authoritative theoretical and practical worker. The
Cramer tri-color filters are not only designed to transmit
regions which the concensus of opinion of the world's best
worker is however the hues of the three-color printing inks
upon which they are coated is tested not only for parallelism,
but also for thickness and planeity. This exhaustive testing
in the laboratory results in a combination of filters and plate
in which the images are of absolutely the same size in all
three plates, and the gradation of the copy is faithfully pre-
served : the optical adjustment of the filter dyes assures
clean and correct "cut outs."
The chief source of trouble to the present day American
worker is however the hues of the three-color printing inks
supplied him by the ink manufacturer which are not nearly
correct.
The G. Cramer Dry Plate Company have recently estab-
lished a Research Laboratory for this and kindred work,
under the direction of R. James Wallace, formerly Head of
the Department of Photophysics of the University of Chi-
cago, and the highest authority in the United States upon
all matters connected with the photography of color. This
Laboratory is equipped with spectroscopic and general phy-
sical apparatus of the most refined, modern type, and its
establishment constitutes an innovation in the dry plate
252 Library of Practiced Photography.
industry of America, which is not even approached by any
other manufacturer. Consultation upon all matters con-
nected with the photography of color will receive courteous
consideration.
PART II.
SEED PLATES.
Special notes treating upon the manipulation of the various
brands of Seed Plates, compiled especially for this
Library by the Seed Dry Plate Company.
642. Without going into a scientific explanation of the
chemical action of the light on the exposed plate, we know
that the plate exposed in the camera bears a latent image of
various light intensities which must be made visible by
development.
643. Intelligent development necessitates a knowledge of
the purposes of the various component parts of the developer.
644. First, we have the developing agent proper (Pyro-
gallic Acid, Metol, Hydroquinon, Eikonogen, or other prep-
arations of a similar nature) which, in solution, in a process
of oxidization, reduces to a metallic form the silver in the
emulsion that has been acted upon by the light. Carbonate
of soda or other alkalies increase the affinity of the developing
agent for oxygen, and also serve the double purpose of open-
ing the cells of gelatin wherein lie the particles of silver to be
acted upon, and this action is slow or rapid in proportion to
the amount and quality of the alkali used.
645. The rapid oxidization of the developing agent by the
alkali needs a corrective agent which we find in sulphite of
soda, which also seeks oxygen, and, used in proper proportion,
controls the color of the resulting image.
special Instruction for Seed Plates. 253
646. Without the sulphite the negative would be yellow
and stained, and as yellow is a non-actinic color, if develop-
ment were carried to a proper point of density, the highlights
would be absolutely incapable of transmitting light, and the
resulting print would be chalky white except in the deepest
shadows.
647. The action of sulphite of soda is to eliminate this
color to a greater or less degree, and the amount used regu-
lates the color, bringing it to the point desired.
648. If too much sulphite be used the resulting negative is
blue-gray in color and as this color readily admits the passage
of light, the resulting prints are apt to be flat and lacking in
brilliancy, unless development is carried to a point of density
where many of the higher tones of light run together and are
lost. The most desirable color, therefore, in a negative is a
warm black with a slight tinge of yellow through the image,
keeping in mind that color is equivalent to density, and carry-
ing development only to the point where the highest lights are
sufficiently transparent to print detail.
649. This character of negative prints quickly, and if
proper balance has been observed in lighting, it will be found
the most satisfactory quality for printing in any medium.
With a proper understanding of the purposes of the chemi-
cals going to make up the developer it is easy to understand
the necessity of maintaining a harmony of arrangement of the
component parts, and to adapt them to the conditions under
which one is working.
650. It is important in this connection to insure a uniform-
ity of harmony by the use of pure chemicals.
651. Many impure carbonates of soda contain caustic soda
or caustic potash, which are most active alkalis, and being an
unknown quantity will produce an alkaline action that one
cannot provide for. Impure sulphites too are apt to have an
indefinite amount of alkali, causing uncertain and variable
action.
652. Seed's sulphite and carbonate of soda obviate these
uncertainties, as they are always pure and uniform in quality,
and once they have been adjusted to produce the required
254 Library of Practical Photography.
quality of negative they can be depended on to give uniform
results.
653. As to the various developing agents in use, each has
its peculiar merits according to the manufacturers, and all are
good, either separately or in the various combinations of
Metol-Hydro, Eikonogen-Hydroquinone, Pyro-Metol, etc., as
given in the formulae following.
654. Pyro, however, seems to hold its own with the
professional photographer owing to the printing color which
it gives and the ease of its manipulation.
655. Temperature in development is an important factor,
and one too often neglected.
656. The dark room and solutions should if possible be kept
at a temperature of sixty-five to seventy degrees Fahr., and the
developer should never be permitted to go above seventy de-
grees in summer, or below sixty-five degrees in winter.
657. Too cold developer in winter produces thin negatives
with an appearance of being under-exposed and this effect is
also due frequently to plates being kept in a very cold room
where they become chilled.
658. Too warm developer, particularly in summer, pro-
duces a heavy, flat quality in negatives, lacking in gradation
and atmosphere, due to a swelling of the minute cells of gela-
tine and running together of the deposit of silver. Every
dark room should be provided with a thermometer, and solu-
tions tested before developing.
659. A pan of ice water in summer or a pan of warm
water in winter in which to set the developing tray tempo-
rarily, will be found useful in maintaining a uniform tempera-
ture during development.
660. Tank development has its advantages in this regard
as'the developer being in a compact body, with such a small
surface exposed to the air, does not change so rapidly in tem-
perature. Any of the following formulae can be adapted to
tank development by the addition of more water to slow the
action and a corresponding increase of sulphite of soda to cor-
rect the additional color that comes from prolonged develop-
ment.
special Instruction for Seed Plates. 255
66i. Certain control is possible in development, particu-
larly if the exposure is known to be over or under the normal,
before development begins.
662. The addition of a few drops of ten per cent, solution
of bromide of potassium to the developer and a decrease of
the alkali will correct to a great degree an exposure that is
very much above the normal. If, however, development has
begun before it is discovered that the plate is over-exposed, the
developer should be washed out of the emulsion, and the plate
immersed in old developer containing bromide. If this does
not bring proper balance of highlights and shadows, develop-
ment should be carried beyond the normal point and the plate
reduced with red prussiate of potash (ferricyanide of pot-
ash).
663. In known under-exposures of portrait, or pictures
made in a low key of light, add two or three times the nor-
mal amount of water (warm if in winter) and a slight in-
crease of alkali, and develop till the detail is well out in the
shadows; then complete development in normal solution.
664. If a plate shows under-exposure after development
begins, take it from the developer and without rinsing it lay
it in a tray of water, repeating the process until the detail is
well out, and then proceed in normal solution to the required
density.
The foregoing applies to indoor exposures.
665. Paradoxical as it may seem, we would recommend op-
posite treatment for instantaneous outdoor exposures. When
this character of exposure is under-timed use less than the nor-
mal amount of water and a material increase in the alkali.
666. The point of complete development is often a matter
of uncertainty with photographers, largely because of the
lack of attention to the temperature of solutions, as negatives
will appear to reduce very much in the fixing if developed in
cold developers, or the reverse if developed in warm solutions.
667. Another cause of uncertainty in this regard is working
in too weak a developing light.
668. The dark room light should be of good volume so
development can be judged up to the last stage.
256 Library of Practical Photography,
66^. There is no light absolutely safe, but a combination
of ruby glass and transparent post-office paper will be safe
in which to examine plates after development has begun, and
should be sufficient volume to enable one to read a newspaper
at a distance of two feet from the light.
670. If the quality of the light is correct the quantity
need cause no alarm. With this kind of developing light, and
provided temperatures are approximately correct, it becomes
only a matter of experience to be able to judge the density of
negatives during development.
671. Complete development of the negative is reached
when all the various light intensities of your subject are re-
corded in their relative values, and the highlights have reached
the limit of density through which you can print detail with-
out obscuring the shadows.
672. There is no rule that can be laid down for determin-
ing when this point is reached. Practice, only, will educate
the eye to correct judgment of complete development.
673. To our amateur friends whose subjects and exposures
vary greatly, we offer the factorial system of development by
Mr. Alfred Watkins. The theory of the system is that no
matter what the exposure, development px-oceeds at a regular
rate. The time of appearance of the first highlights of the
image is a definite fraction of the time in which development
is completed.
674. Example. — Highlights appeared in 24 seconds and
the plate was taken out 240 seconds after the developer was
poured on. The print from this negative showed proper
contrast.
240 seconds total development.
24 seconds highlight appeared.
10 factor for developer.
For future development with a watch or metronome, note
the number of seconds elapsed between the pouring on of the
developer and the appearing of the first highlight.
675. Example. — Highlights, 35 seconds; time, 10-350
seconds. Cover tray to protect from the developing light and
special Instruction for Seed Plates.
257
continue rocking. Three hundred and fifty seconds after the
start take the plate from the developer, rinse and fix.
Different developers have different factors. We suggest
the following factors for use with our own developing formula :
Pyro 12
Metol-Hydro 15
Eiko-Hydro 12
Hydroquinone 4
676. To use this system successfully, always use a normal
developer.
For stronger negatives than the normal factor gives, use a
higher factor. For weaker negatives use a lower factor. If
the lighting is too uniform, flat prints will result and longer
development will not improve the contrasts.
677. Temperature of the developer is an important condi-
tion in using the factor system. It should be kept uniform
during development. Seventy degrees is normal for a devel-
oper. Cold developer works too slow and warm developer too
fast. With a temperature of about eighty degrees there is
danger of frilling.
678. Developers For Use With Seeds Plates.
Pyro.
BY WEIGHT.
Pure Water 16 ounces.
Pyro I ounce.
Oxalic Acid 10 grains.
B.
Pure Water 16 ounces.
Seeds Sulphite of Soda . . 2 ounces.
C.
Pure Water 16 ounces.
Seeds Carbonate of Soda 2 ounces.
USE
A I ounce.
B 1 ounce.
C 1 ounce.
Pure Water 7 ounces.
BY HYDROMETER TEST.
A.
Pure Water 16 ounces.
Pyro I ounce.
Oxalic Acid 10 grains.
B.
Seeds Sulphite Soda Solution
Test 60.
C.
Seeds Carbonate Soda Solution
Test 50.
USE
A I ounce.
B I ounce.
C I ounce.
Pure Water 7 ounces.
Factor 12.
258
Library of Practical Photography.
679. In very cold dark rooms use five ounces of water. In
hot weather use ten ounces of water. For double coated
plates use eighteen ounces of water.
One-half ounce of ^ will give a warmer tone to the nega-
tive. The best printers have a warm brownish black color.
If negatives are too yellow or the shadows show the slightest
stain, not due to discolored fixing bath, use one and one-half
ounce of ^.
680. Sulphite of soda in solution does not keep well.
Solutions over one month old should not be expected to be full
strength if not made with pure water, and kept in well stop-
pered bottles.
681.
Eikonogen-Hydroqjjinonk.
BY WEIGHT.
A.
Pure Water 48 ounces.
Seeds Sulphite of Soda 2 ounces.
* Eikonogen 240 grains.
Hydroquinone 60 grains.
B.
Pure Water 16 ounces.
Seeds Carbonate of Soda 2 ounces.
USE
A 3 ounces.
B I ounce.
BY HYDROMETER TEST.
A.
Seeds Sulphite of Soda Solution
Test 20 48 ounces.
* Eikonogen 240 grains.
Hydroquinone 60 grains.
B.
Seeds Carbonate Soda Solution
Test 50.
USE
A 3 ounces.
B I ounce.
Factor 12.
For double coated plates add four ounces of pure water.
Use more water in hot weather.
* If more concentrated developer is desired in order to secure more
contrast, the water in solution A may be reduced to 32 ounces. Use
boiling water in making up this developer. In cold weather a little
glycerine could also be added to prevent precipitation.
special Instruction for Seed Plates.
259
682.
Metol-Hydroqjljinone.
BY WEIGHT.
Pure Water 64 ounces.
• Metol 120 grains.
Hydroquinone 120 grains.
Seeds Sulphite of Soda 2 ounces.
B.
Pure Water 16 ounces.
Seeds Carbonate of Soda 2 ounces.
USE
A 4 ounces.
B I ounce.
Pure Water 4 ounces.
BY HYDROMETER TEST.
_
Pure Water 48 ounces.
* Metol 120 grains.
Hydroquinone 120 grains.
Seeds Sulphite Test 60 16 ounces.
B.
Seeds Carbonate Soda Solution
Test 50.
USE
A 4 ounces.
B I ounce.
Pure Water 4 ounces.
Factor 15.
•Dissolve in the order given. Metol should always be dissolved
in water before the sulphite is added, or before it is mixed with
sulphite solution, otherwise it may precipitate. If crystal sodas are
used add 15 grains of bromide of potassium to 16 ounces of B solu-
tion.
683. Ortol.
A.
B.
Pure Water 24 oz.
Potass'm Meta bi-Sulphite. 90 gr.
Ortol 180 gr.
Pure Water
Seeds Sulphite
Seeds Carbonate ....
. . .24 ounces.
... I ounce.
... I ounce.
Use equal parts of A and B.
Factor 11.
684. Pyro-Mktol.
BY HYDROMETER.
To
A.
Pyro I ounce.
Develop Take
Metol 60 grains.
Water 221^ ounces.
Water.
A
8 to 10 ounces.
I ounce.
B.
Seeds Sulphite — test 60.
C.
B
C
1 ounce.
I ounce.
Seeds Carbonate Soda — test 50.
This develoi>er gives softness and detail.
260 Librar}f of Practical Photography.
685. Plain Fixing Bath.
BY WEIGHT.
Pure Water 16 ounces.
Hypo 4 ounces.
Hydrometer Test 70.
Do not use a discolored bath. Plates should be left in Fix-
ing Bath at least double the time it takes whiteness to disap-
pear. This bath must be made fresh every day.
686.
Acid-Fixing Bath.
BY WEIGHT.
A.
Pure Water 96 ounces.
Hypo 2 pounds.
Seeds C. P. Sulp'te of
Soda 2 ounces.
B.
Pure Water 32 ounces.
Chrome Alum 2 ounces.
Sulphuric Acid C. P.. . 1^ ounce.
BY HYDROMETER TEST.
A.
Hypo Test 80 100 ounces.
Seeds Sulphite Test
60 16 ounces.
B.
Chrome Alum Test 20. 32 ounces.
Sulphuric Acid C. P. . . . 2 drams.
687. See that chemicals are entirely dissolved, then pour
£ into A slowly while stirring A rapidly. This bath remains
clear and fixes clean after long continued use, but should be re-
placed as soon as it becomes exhausted. Never attempt to re-
store a spent bath by adding more hypo. Plates should be
left in bath at least double the time it takes whiteness to dis-
appear.
688. If negatives remain twenty to thirty minutes in this
bath, the film will become much hardened. This is a great
advantage in summer when washing often softens the film.
In hot weather fresh fixing baths should be made up more
frequently. By fixing longer, less washing will suffice ; fif-
teen minutes in running water is enough if plates have been
thirty minutes in a fresh, quick working fixing bath.
689. Weights.
The ounce avoirdupois (437^ grains) is the one used.
The quantities given in formulae are mostly divisible by
Special Instruction for See J Plates. 261
four, if smaller quantities of developer are desired. The fol-
lowing approximate metric equivalents may be used:
i6 ounces (fluid) coo cc.
I ounce (weight) 30 grams
60 grains 4 grams
PLATES FOR PORTRAITURE AND GENERAL WORK.
Gilt Edgs 27.
690. This is the fastest plate we make. It is especially
suited for all extremely short exposures and flash-light work.
Speed is a great help in winter, for then the light almost al-
ways seems stronger than it really is, and under-exposures are
frequent. On such days when the light is changeable and un-
certain, Gilt Edge plates make the most of short exposure and
their unusual latitude saves many plates, even when there is
large error on the side of over-timing. Owing to their ex-
treme rapidity in portrait work the lighting of the subject
should show more snap and roundness than when a slower
plate is used. Quality has not been sacrificed to speed in our
twenty-seven. It has the fine grain and characteristic Seeds
gradation, which means pictures with harmonious contrasts,
softness and depth.
26x.
691. Our 26x is the most extensively used plate we make.
For general portrait work it cannot be surpassed. It gives
roundness in gradation from the highest lights to the deepest
shadows. There is brilliancy, harmony, and detail through
the whole picture. Light the subject as you would have
your picture. Only extremes, /. e., light so strong and con-
centrated as to show unusual harshness, or so broad and so
much diffused as to give no point to highlight or shadow,
need be avoided. The plate will give you what you see under
most adverse circumstances. The 26x plate has a wider lati-
tude than any other portrait plate in the world. It requires
one-fourth more exposure than the Gilt Edge 27.
II— 15
262 Library of Practical Photography.
692. Seeds Tropical Plates. — The Seeds Tropical is a
new plate made for use in hot climates, which will be heartily
welcomed wherever heat and humidity make the working of
the ordinary plate a difficult matter.
The Seeds Tropical Plate is similar in speed, latitude and
gradation to the Seeds 26X, but will not frill, even though the
temperature of the developer be as high as ninety degrees
Fahr. The proper temperature for working this plate is in
fact from seventy degrees to ninety degrees without danger of
frilling, and thus gives the benefit of the " Seeds quality" to
those who, on account of climate or on account of difficulty in
obtaining ice, are not able to properly control the tempera-
ture of their solutions.
Use our regular pyro formula for developing.
Note. — Developer made up according to the regular formula is in-
tended for use at a temperature of about seventy degrees. If devel-
opment is carried on at eighty-five degrees or ninety degrees the de-
veloper must be diluted one-half by adding water, using fourteen ounces
instead of seven ounces.
DOUBLE COATED PLATES FOR THE PREVENTION OF
HALATION IN CASES WHERE CONTRASTS OF
LIGHT AND SHADE ARE NECES-
SARILY VIOLENT.
693. Non-Halation Plate. — In photographing interiors
the strongest highlights, such as the windows and other out-
5f-door openings, are almost always very dense and blurred at
the edges. This is due to halation or reflection from the inner
surface of the glass. Our Non-halation plate is double coated,
under coat a 23, the surface a 26x. Consequently, though it
has the speed of a 26x, the blur of halation is lost in the bril-
liant 23 emulsion next to the glass surface. This means that
in poorly lighted interiors an exposure sufficient to get detail
in the shadows will not endanger the highlights. Snappy
detail in the highlights under most trying conditions is the
special Instruction for Seed Plates. 263
characteristic performance of this plate. It is especially serv-
iceable in photographing machinery where bright parts and
troublesome reflections are unavoidable. We most strongly
recommend it for all landscapes, seascapes, white draperies,
wedding gowns and other subjects where it is necessary to
bring wide contrasts of light and shade into harmony. We
also offer it to the amateur as a most economical plate for gen-
eral use, on account of its remarkable latitude.
694. The normal developer used with ordinary plates
should be diluted with an equal volume of water. This allows
the developer to penetrate to the lower film before develop-
ment has made much progress in the upper film. Both films
should develop simultaneously. Development in the diluted
developer will be much slower, but the results will show.
695. Since the Non-halation is double coated it is almost
impossible to judge its density by the developing light as in
ordinary practice. It is therefore conservient to determine
the completion of the development by using the factor system.
Development with pyro (diluted), will be completed in about
fourteen times the time in which the highlight appears. The
speed of the Non-halation plate may be reckoned the same as
the 26x. It should be noted, however, that only in very full
timing can the whole advantage of the great latitude and
wonderful gradation of this plate be brought out.
696. Orthochromatic Plates. — One of the signs of the
times is the increasing demand for orthochromatic plates
in all classes of work. These are undoubtedly the plates of
the future. They will do all that an ordinary plate of the
same general character will do, and in many cases much more.
Therefore we have been ever ready to meet the demand of
the trade for orthochromatic plates of special character for
special work. For general all-around work, where the high-
est color sensitiveness is demanded, the Ortho and the Non-
halation Ortho; for commercial work and the reproduction
of furniture samples, where increased contrasts are de-
manded, the C Ortho. With a little care in handling, any
of our orthochromatic plates may be developed without trace
of fog in a ruby light safe for ordinary plates.
264 Library of Practical Photography.
697. Ortho. — It is well known that yellow and green
values are the life of the picture in many a landscape. In or-
dinary photographs these bright patches of color are shown as
black or very dark. About 90 per cent, of landscape photo-
graphs neither give all that the eye sees, nor show the proper
relation in what they do give. For instance, it will be found
quite impossible to secure with one exposure on an ordinary
plate, printable detail in a foreground of green foliage as well
as in the light clouds on the horizon. When the Ortho plate
is used this is easily obtained. It is impossible on an ordinary
plate to get values in autumn scenery. The brilliant coloring
of the foliage is much more dull, black and lifeless than it
should be. With an Ortho plate the picture tones up wonder-
fully.
698. The improvement made by the use of an orthochromatic
plate will be noticeable. But with a filter difficult problems
become easy, and true and exact rendition of color value is ob-
tained. For this purpose we make two filters, a light one for
general landscape work and a deep one for work where more
exact rendition is necessary as in the reproduction of paint-
ings. These filters are specially adjusted for use with our
Ortho and Non-halation Ortho plates and should not be used
with any other plates.
699. We strongly commend our Ortho plate to microscopic
workers. Because of its high sensitiveness to yellow light the
exposure, in cases where the subjects are in yellow stain, will
be very much reduced. Subjects in blue stains cannot be
photographed successfully on an ordinary plate, but with an
Ortho this is possible. A light yellow screen will be useful
in obstinate cases.
700. For general all-around work, as well as work in
which the highest color sensitiveness is demanded, the Ortho
is supreme among single coated plates. It has a most pleas-
ing gradation, vigor, roundness, and fullness, without that
harshness which so often characterizes a plate of great color
sensitiveness, and which tends to the production of pictures
in which chalk and soot effects prevail. Speed is the same
as our 26x.
special Instruction for Seed Plates. 265
701. Non-Halation Ortho. — Many advanced workers use
but one kind of plate for all their work. There is much to be
said for this system. It is a very rational way of working.
To these we especially commend the Non-halation Ortho
plate, for it has all the qualities of our regular Non-hala-
tion, and all the color sensitiveness of our Ortho. The speed
is the same as our 26x, and the latitude the same as the regu-
lar Non-halation. It is unquestionably the best plate made in
adaptability to every special need in difficult or varied work,
PLATES FOR SPECIAL, COMMERCIAL
AND PROCESS WORK.
702. Commercial Ortho. — There has been an increased
demand from commercial workers for a plate suitable for re-
production of the grain of wood in mahogany furniture, dark
oak, and bird's eye maple. Much practical experience led to
the production of this emulsion. The plate has wonderful
latitude and a lack of intensity in the middle tones which is
so necessary in this class of work. It is so highly orthochro-
matic as to render all the detail in yellow objects with very
short exposure. Its keeping quality is most excellent. This
is of the utmost importance in work where quantities of plates
must be kept for some time and where increased contrast
between the highlights and middle tones is necessary to good
results. It has great latitude, works with vigor and is unus-
ually brilliant. Speed same as 26x.
7°3' 23 Plate. — This is a slow plate and especially suited
for commercial and landscape work. It works with more con-
trast than the 26x and requires about double the time.
704. Process Plate. — This is an emulsion of strong con-
trasts, especially suitable for giving black and white effects,
for copying drawings, manuscripts, plans and printed matter.
It requires six times longer exposure than the zSx.
705. Lantern Slide Plates. — Our Regular Brand is made
with the most perfect glass obtainable. It produces a rich
black tone, very bright and crisp. It requires 5 to 6 seconds'
exposure at 2 feet from a i6 c. p. lamp. Full directions for
development in each box.
266 Library^ of Practical Photography.
706. We recently added another slide plate which we have
named the "Red Label "brand. It gives warm black or
brown tones by a change in the developer, producing brilliant
slides with beautiful detail. We offer this brand at a lower
price than our regular plate and we predict that the quality
and price will soon make it the most popular slide plate on
the market. Full directions for exposure and development
follow.
707. Developers for Lantern Slides, Transparency
and Process Plates.
Black and Brown Tones. — Developer for
Black Tones.
No. I. No. II.
Pure Water 24 ounces. Pure Water 16 ounces.
Seeds Sulphite Soda. 3 ounces. Potass. Carbonate.... 2 ounces.
Hydroquinone 150 grains. Bromide Potass 15 grains.
To Develop.
Take of No. I. — 3 ounces; No. II. — 2 ounces.
Developer for Warm Tones.
No. I. No. II.
Pure Water 16 ounces. pure Water 16 ounces.
Hydroquinone 50 grains. Potass. Carbonate. ... 480 grains.
Seeds Sulphite Soda. . 50 grains.
Bromide Potass 24 grains.
Citric Acid 6 grains.
To Develop.
Take equal parts.
For still warmer tones the amount of sulphite may be re-
duced.
To make a lantern slide by contact, put the negative face
up into an ordinary printing frame and place the lantern slide
plate face down upon it, just as with printing on paper.
708. Exposure: As a guide we give the following ex-
ample (taking a medium dense negative), if a 16 c. p. electric
special Instruction for Seed Plates. 269
light is used the exposure should be about two seconds for
black tone slides and three seconds for warm tones at a dis-
tance of three feet from the light.
709. It should be borne in mind that the results depend
much upon the correctness of exposure, hence judgment and
practice are necessary with the varying characters of negatives.
If there is a doubt in the mind as to the time of exposure re-
quired for a certain negative, we would suggest that the aim be
for under-exposure rather than over, for a slightly under-ex-
posed lantern slide is always more satisfactory than an over-
timed one, because of the indistinctness of the picture when
thrown on the canvas.
710. To Develop: Temperature of developer should be
between 70 and 75 Fahr., and if exposure and temperature of
developer are correct the time of development will be about
three minutes for either black or warm tones. To proceed,
lay the plate face up m a suitable tray and flow the developer
over it, allowing the developer to act until sufficient density in
the shadows is obtained, then wash well and immerse in the
fixing bath.
711. Fixing Bath.
A. B.
Water 64 ounces. Water i6 ounces.
Hypo 1 pound. Chrome Alum i% ounce.
Sulph. Soda 2 ounces. Sulphuric Acid (cone.) i dram.
While stirring A vigorously, pour in B very slowly. This
bath will keep, but should be filtered occasionally. The
chrome alum bath recommended for our regular plates can be
used, also fresh plain bath, hypo 4 ounces, water 16 ounces.
712. Leave plate in bath a few minutes after all white has
disappeared from back. Wash well and then wipe surface
gently with a wad of wet absorbent cotten. Rinse and set to
dry in a ventilated place free from dust. Do not change po-
sition of plates while drying as it will show a difference in
intensity with different conditions of air.
713. Orthochromatic Plates and Light Filters. —
When, a few years ago, Orthochromatic plates made their in-
270 Library of Practical Photograph}).
itial appearance before the photographic public, the venture
was looked upon by the average amateur merely as a some-
what interesting experiment. The importance of the discov-
ery which rendered such a product possible was not realized
and although conceded to be of much interest, yet it did not
seem to materially concern their work. The professional pho-
tographer simply ignored them.
714. The Orthochromatic plate, however, has steadily
gained in favor and the many " conventions " and "salons"
which have been organized in later years have greatly served
to demonstrate the advantages to be gained from their use,
until, at the present time, there is no plate maker of note
throughout Europe or America who does not supply such an
article in one or more "brands."
715. The principles of orthochromatism are now (thanks
to the many writers on that subject) fairly well understood
among photographers, but to the ever increasing army of new
workers a brief explanation is essential to intelligent use, while
even to those who are further advanced, a concise account
may not be out of place.
716. Briefly : " White " light, so called, is a complex mix-
ture of seven different colors which are respectively red, or-
ange, yellow, green, blue, indigo, and violet, and these col-
ors arranged in the above order constitute the " visible spec-
trum " (or image) of that light when it is observed through a
glass prism. Besides this there is another region known as the
ultra-violet, which is totally invisible to the human eye, but
to which the photographic plate is very sensitive — whether
it be " ordinary "or " orthochromatic."
717* All objects in Nature appear colored because they re-
flect more of some one color than another — those colors
which they reflect less being absorbed by the object itself.
718. The ordinary photographic plate is not sensitive to
all of those colors, but only to a very limited number — in
fact only three — the blue, indigo, and violet; and also to the
ultra-violet. The result is, that the red, orange, 5'ellow or
green have no action on the plate at all, and hence are rep-
resented as black. The print then is altogether untrue to the
special Instruction for Seed Plates.^ 271
original in all save shape — a dark violet object for example,
being represented as a bright white ; while, on the contrary,
the brightest of all colors — yellow — will be black.
719. The Orthochromatic plate is the result of the addition
of certain dye stuffs into the sensitive coating, which makes
the plate capable of being impressed by other colors, viz., the
yellow and green.
720. Although the plate is now sensitive to yellow and
green, yet it is still much more sensitive to blue, violet, and the
invisible ultra-violet, and, to render the colors of Nature in
anything like their relative brightness to one another, it is
necessary to tone down those colors which act too strongly,
so that the others may have a chance to impress themselves
with sufficient strength. This is accomplished by the employ-
ment of a colored screen, or more properly speaking — a light-
filter.
721. The first object of such a filter is to cut off entirely
the invisible ultra-violet, so that it may no longer impress it-
self. Next, it must absorb a definitely measured amount of
blue, indigo and violet lights, so that they do not act any
more strongly than is necessary to show objects so colored in
their proper brightness. If the filter should tone down these
hues too much, then the result would be just as far wrong the
one way as it was the other It is therefore obvious that a
filter adjusted to one make of orthochromatic plate, will not
give equally good results with some other.
722. The Seeds "Chromatic Curve" filter is adjusted by
careful spectroscopic and other measurements, so that it con-
forms exactly to the needs of the Seeds "ortho" plate, the
combination giving results which reproduce with the utmost
fidelity the varying luminosities of the object photo-
graphed.
723. The Seeds "Compensator " filter is very much lighter
in color, and — as its name implies, is for use in compensating
the errors of the plate — its duty is to absorb entirely and
completely the invisible ultra-violet, and slightly subdue the
visible violet. (This filter does not possess the measured ad-
justment of the " Chromatic Curve.")
272 Library^ of Practical Photography.
724. These filters are arranged for the utmost convenience
in every day use, being manufactured of optical plane glass,
held in a handsome metal cell with adjustable clasps to fit
slightly varying sizes of lenses.
725. In use, the filter is simply slipped on the front of the
lens hoodj and focusing proceeded with as usual.
726. The Panchromatic Plate. — Orthochromatic pho-
tography is the means by which we obtain, with the aid of
properly prepared plates, the light intensity values of objects
not obtained by the use of the ordinary dry plate, commonly
used in photographic work.
727. Orthochromatic, from the Greek words, Orthos^
correct, and Chroma == color.
728. The Panchromatic plate, a late addition to the utili-
ties in the field of orthochromatic photography, is so prepared
that it is sensitive, in almost a like degree, to all colors
under certain condition, i. e., in combination with various
color screens.
729. One must not, however, form the impression that
color contrasts can be rendered, but it makes possible the
recording in monochrome, contrasts of light and shade in
proportionate intensities as seen by the naked eye. This in
turn requires that we determine the predominating color, and
select the screen that will give to that particular color and
minor surrounding colors, the best value as to their light
and shade.
730. The extreme sensitiveness of this plate to the various
colors make it valuable in connection with the Three-color
Process which, as is well known, requires that three separate
negatives be made, termed the Red, Blue and Yellow plates,
necessitating the use of three separate color screens, green,
red, and violet.
731. Development. — Due to its sensitiveness, the Pan-
chromatic plate should be developed in total darkness for from
five to six minutes (according to the density required in the
negative).
special Instruction for Seed Plates. 273
733. Formula.
By Weight.
A. — Pure Water 16 ounces
Pyrogallic Acid i ounce
Oxalic Acid lo grains
B. — Pure Water i6 ounces
Sulphite of Soda 2 ounces
C. — Pure Water 16 ounces
Carbonate of Soda 2 ounces
Use A I ounce ; B 1 ounce ; C i ounce ; Pure Water, 7 ounces.
By Hydrometer Test.
A. — Pure Water 16 ounces
Pyrogallic Acid i ounce
Oxalic Acid 10 grains
B. — Sulphite of Soda, Solution Test sixty degrees.
C — Carbonate of Soda, Solution Test fifty degrees.
Use A I ounce; B i ounce; C i ounce; Pure Water, 7 ounces.
Note. — Extreme softness, or low tone values, may be had by dilu-
ting the normal developer and increasing the time of development ac-
cordingly.
A fresh fixing solution should be used in order that the
plates are free from all stains.
After fixing they may be handled in the usual manner.
PRACTICAL ADVICE.
733. Exposure. — For most subjects the latitude of a plate
will be about two, that is, if one second were correct expos-
ure, two seconds would not be too much for safety. For be-
ginners an open, sunlit landscape is a good subject for the first
experience. Try three exposures i-ioo, 1-50 and 1-25 of a
second. In some cases all three might be good and in others
none, but there will be evidence enough to give a line on cor-
rect exposure. If the shutter has but one speed, or is not re-
liable, the same experiment may be tried by starting at a full
open lens and reducing the stop one size each time.
734. The light varies in intensity from hour to hour during
the day and from month to month during the year. In win-
274 Library of Practical Photography/.
ter exposures at noon should be from two to four times longer
than at noon in June.
735. Exposures near sunset should be five to ten times
longer than at noon. On hazy days when sun casts weak
shadows, expose twice as long as on bright days, when the
sun casts deep black shadow.
736. On very dull days when the sun casts no perceptible
shadows expose four times as long as for bright days. Even
at best the picture will be flat, but if under-exposed it will also
be weak and thin. If a landscape has dense foliage in the
foreground double the exposure.
737. Sea and snow require but one-half to one-fourth land-
scape time.
738. Developing Light. — Ruby glass is the best me-
dium to use in the construction of a light. Some ruby glasses
pass light which will fog a plate in short order, but a large
percentage of them are safe for all practical purposes. The
principal object is to see what is doing. There is least strain
to the eyes when the light which illuminates the work is
moderately strong but not harsh. A little diffusion through
several sheets of yellow tissue paper will secure this quality.
It will be found that no light in which the shape of the illum-
inant (gas flame, or candle, or incandescent filament) can be
distinguished, is a safe or pleasant one to use.
739. There is hardly any light which is safe and at the
same time strong enough to be useful. The proper way is to
get a diffused red light which is comfortable and then make a
practical test to see how soon a plate exposed to it fogs.
740. Put a plate in the plate holder in perfect darkness ;
then place the holder where you generally develop, draw the
slide half across the plate and expose to the developing light
as long as it generally takes to develop a negative. Then de-
velop the plate in perfect darkness the usual time , wash and
fix. If any difference is then found between the exposed and
unexposed parts of the plate, it is proof that the light is not
safe for very sensitive plates.
741. It should be pointed out that Orthochromatic plates
are very much more sensitive to the developing light than reg-
special Instruction for Seed Plates. 275
ular plates and therefore require some special care in hand-
ling, though they do not necessarily require a special light for
their development. The ordinary light will be quite satisfac-
tory unless the development of the fastest ordinary plates by
It is risky. After the developer has been poured on, Ortho-
chromatic plates are not a great deal more sensitive to red
light than ordinary plates. The greatest care should be in
handling before development. Keep as far away from the
light as possible until the plate is covered with developer.
742. Drying Negatives. — The warmer the air in which
negatives are dried, the more intense they become. Negatives
should be dried in a current of air. If more than two hours
are consumed in drying, trouble may result, even if the tem-
perature be moderate. Never move negatives from one place
to another during drying, or marks will result.
743. Flat Negatives. — When the negatives are thin
and weak and density cannot be gained in prolonged develop-
ment, under-exposure is the cause.
744. When there is good printing detail in the shadows,
but the highlights lack point and snap, too flat lighting is the
cause. Use rounder contrasts so as to give the highlights a
full exposure. The light which models the subject should be
sufficiently concentrated. Do not use too diffused a light on
the subject, or relieve the shadows by a side reflector. Use
the reflector more from the front, if at all.
745. Under-development causes lack of contrast. Do not
be deceived by apparent strength, when developer is of higher
temperature than 75 Fahr.
746. Frilling and Softening of the Film. — Keep
developer under 75 Fahr., and baths and washing water as
near that temperature as possible. Any large difference in
the temperature of these solutions will cause frilling in any
kind of weather. Use ice to keep the developing solution at
proper temperature. If ice is not at hand use more water in
developer. Use fresh, quick working baths or the acid hard-
ening bath. Fix longer and wash less. Plates should be
thoroughly fixed and then washing fifteen minutes in running
water will be sufficient
276 Library of Practical Photography.
747. Weakness of Image. — Due to under-development,
caused by too cold or to weak developer. Developer should
be 70 degrees Fahr. in temperature and contain 2^ to 3 grains
of pyro to the ounce of developer. After development the
developer (pyro) should be clear red and not a dirty brown,
748. Slowness of Development. — Caused by cold or
weak developer or under-exposure. Often a smoky lens or
dirty skylight causes the under-exposure. It should be pointed
out that developers made with Seeds Sodas develop more
slowly, but their action is more uniform and the negatives are
clearer and brighter.
749. Too Much Contrast is generally caused by harsh,
unnatural lighting of the subject. If the plate is under-ex-
posed, too much contrast frequently results from carrying on
the highlights to too great density in hope of bringing out
more detail in the shadows. The best results in under-expos-
ure are obtained by stopping development before the high-
lights come to the limits of printing density.
750. Fog. — Fogged negatives are frequently caused by an
unsuitable developing light. Prolonged or forced develop-
ment, allowed in hopes of getting more density than the ex-
posure and lighting should give, veils the shadows. Too
much alkali or too warm developer also cause fog. Use nor-
mal developer at a temperature of 70 degrees Fahr. Leaky
cameras or plate holders cause foggy or light struck negatives.
The little shutter in the plate holder may not close after the
slide is drawn. Avoid the possibilities of these troubles by
making a habit of covering the camera and plate holder with
the dark focusing cloth during drawing of slide and exposure
of plate.
751. Our Demonstrators frequently find that light enters
the camera where the bellows are attached to the back part
of the camera, between the back board and carriage for holder
and between holder and carriage. This defect has so often been
found to be the cause of flat, weak, foggy negatives, that we
give the following directions to discover it. Take the camera
out into strong light, take out lens and facing the light place
head in camera until the forehead touches the back of the plate
special Instruction for Seed Plates, 277
holder. Remain in this position until the eyes become accus-
tomed to the absence of light, for until then the leak would
not probably be seen.
752. Fog is also caused by dust or a hazy atmospheric de-
posit on the lens which carries a diffused light into the camera,
distributing it over the plate. Keep lenses clean.
753. To Clean a Lens. — First spread upon a table a
clean sheet of paper ; take your lens carefully apart ; now dust
with camel's-hair brush each lens on both sides ; then take a
clean graduate, pour in two ounces of distilled water, one
ounce of alcohol and three drops of nitric acid (C. P.), mix
well, and with a tuft of filtering cotton dipped in this solu-
tion, rub the lens on both sides ; polish with a clean chamois
which is kept for this purpose only, which, when not in
use, put away in a clean paper bag. After the lenses are all
polished, before putting together, wipe out carefully the brass
tube ; then dust each lens with a camel's-hair brush (never
blow on them) and put together. A lens cleaned in this way
will keep clean much longer than it would if simply wiped
with a chamois.
754. Spots. — Numerous round and very small transparent
spots are generally due to rinsing the plate before develop-
ing. Carefully avoid this with our plates.
755. Large round spots, but less numerous, are caused by
bubbles in the developer, often due to water containing vege-
table matter. Melted ice, distilled or well water should be
used if possible. Angular spots are due to dust on the plate
at the time of exposure. Plates should be dusted with a
camel's hair brush before development and the plate holder
and camera kept scrupulously clean. The dusting may elec-
trify the plate if done too vigorously.
756. Triangular Transparent Spots are caused by
using a developer on which a scum has formed. It should not
be used without filtering. The scum forms rapidly if the room
is warm and the water used contains organic matter.
757. Opaqjue Spots and Lines are caused by allowing
pyro, hypo or sal soda to get on the dusting brush. The dark
room should be kept absolutely clean, any spilled hypo or other
278 Library of Practical Photography.
solutions should be wiped up immediately, for after drying
the dust of chemicals will float about in the air and cause
endless trouble.
758. Small Opaque Spots may also be due to the presence
of iron in the water. To avoid same a canton flannel bag
should be so tied over the faucet that the water filters through
it. The spots may be removed by diluted sulphuric or muriatic
acid.
759. Blurred Opac^JE Finger Marks or Spots are
caused by placing plates face to back after exposure. Plates
left in such contact any length of time will transfer any mark-
ings from the back of one plate to the sensitive surface of an-
other. Always put plates away face to face after exposure.
760. Granularity of Negative. — This is usually a
warm weather trouble. The developer should not be too strong
in alkalinity or too warm. Fix well in a strong, fresh, acid
alum bath. Dry in a current of air.
761. The Making up of Developer Solutions. — If
distilled water only were used in making solutions of devel-
oper, half the troubles of development would be avoided. If
river water is taken, it should be boiled, cooled and filtered
before mixing, as it generally contains much vegetable and
other organic matter. Well water that is free from iron and
sulphur, and not too alkaline, may be used without boiling.
Melted ice is good, but should be filtered.
762. The Developer should be made up with reliable
chemicals to an established formula strictly according to in-
structions. When a convenient way of making up the solu-
tion has been fixed upon, those particular weights and measures
should be used thereafter. This procedure should be so much
a habit, and the confidence in the materials used (this includes
the water) should be so based upon past experience or the
guarantee of reliable people, that the developer should be the
last place to look for trouble. A great many troubles laid at
the door of the developer, are the result of mistakes in expos-
ure and lighting. The worker should be sure that his lighting
ought to give him the desired contrasts and that his exposures
are sufficient and not too great, before blaming the developer.
special Instruction for Hammer Plates. 279
PART III.
HAMMER PLATES.
Special notes treating- ufon the manipulation of the various
brands of Hammer plates, compiled especially for this
Library by the Hammer Dry Plate Company.
( For the best results we recommend Hammer formulae
for Hammer plates.)
763. For professional work we think pyro and soda pro-
duces negatives that have the best printing quality (others
may think differently ; everyone is entitled to his own opin-
ion).
764. But never condemn nor criticise the chemical effect of
a Hammer Plate when it has been developed with some other
formula (a formula that has been prepared for some other
plate).
765. Any good developer may be used on the Hammer
Plate, but if you want to use the developer that is best suited
for the Hammer Plate and consequently will produce the best
results, use the pyro and soda formula as published herein.
Most other developers are stronger than necessary for this
plate. The quality is in the Hammer emulsion and does not
require any forcing to bring it out. Chemical actions that
are forced through hurriedly will result in loss of quality.
766. Important Caution. — The importance of care in
weighing and measuring the several ingredients of a developer
cannot be too strongly urged. The quantities and propor-
tions recommended in the several formulae herewith have been
arrived at after most careful study and experiments. Devel-
opers cannot be made up successfully by guesswork. If the
best results are desired with any given formula, its proportions
must be accurately weighed and measured.
GOOD DEVELOPING FORMULAE FOR
HAMMER PLATES.
767. The quantity of sodium sulphite in the developer
must be regulated to produce the color desired. It is to the
II — 16
280 Librar}f of Practical Photography.
photographer's advantage, when using pyro developer, to use
our formula, as most other formulae call for more pyro than is
necessary for our plates.
Pyro and Soda (By Weight).
No. I
English Weights Metric Weights
and Measure. and Measure.
30 ounces Pure water or 900 c.c.
5 ounces Sodium Sulphite ( crystals). .. .or 150 grammes
2)^ ounces Sodium Carbonate (crystals) ..or 75 grammes
No. 2
24 ounces Pure water or 720 c.c.
15 grains Oxalic Acid (dissolved) or i gramme
And then add —
I ounce Pyrogallic Acid or 30 grammes
To develop, take : —
I ounce of Solution No. i or 30 c.c.
}i ounce of Solution No. 2 or 15 c.c.
6 to 8 ounces Pure water or 180 to 240 c.c.
More water may be used in warm weather, and less water
in cool weather.
768. Pyro Developer with Carbonate of Potash.
No. I
Engli.sh Weights Metric Weights
and Measure. and Measure.
33 ounces Pure water or 960 c. c.
8 ounces Sodium Sulphite (crystals) ....or 240 grammes
I ounce Carbonate of Potash (dry) or 30 grammes
No. 2
24 ounces Pure water or 720 c.c.
15 grains Oxalic Acid (dissolved first) or i gramme
1 ounce Pyrogallic Acid or 30 grammes
To develop, take : —
I ounce of Solution No. i or 30 c.c.
)^ ounce of Solution No. 2 or 15 c.c.
6 to 8 ounces of Pure water or 180 to 240 c.c.
special Instruction for Hammer Plates. 281
When the plate is fully developed and you find the high-
lights too thin, use less water in the developer; if too dense,
use more water.
769. Pyro and Soda. ( Three solutions by ivetght and by
hydrometer.) — This formula is better suited to all localities than
is a two-solution developer. Each property of the developer
being separate, the user can vary the quantity of either to meet
local conditions. The water in some places is alkaline ; then
less of No. 2 Carbonate of Soda should be used. A few trials
will indicate the amount that should be used in order to pro-
duce the best results. In cold weather the carbonate of soda
can be increased a little. During hot weather it is generally
best to use a little less of the No. 2 solution, for if the temper-
ature is very high and too much of this chemical is present,
the user will destroy the clearness of his plate. The sulphite
being in a separate (No. i) solution, the user can easily mod-
ify results by varying the proportion. The water in some
localities does not require as much sulphite as in others. Use
just enough of the sulphite solution to give the proper print-
ing color to the negative (just a trace of yellow).
No. I
English Weights Metric Weights
and Measure. and Measure.
15 ounces Pure water or 450 c. c.
5 ounces Sulphite of Soda (crystals) or 150 grammes
Hydrometer test eighty degrees.
No. 3
15 ounces Pure water or 450 c. c.
2% ounces Carbonate of Soda ( crystals ) or 75 grammes
Hydrometer test forty degrees.
No. 3
34 ounces Pure water or 720 c. c.
15 grains Oxalic Acid or i gramme.
I ounce Pyrogallic Acid rr 30 grammes
To Develop, Take:
"^ ounce of each, No. i, No. 3, No. 3 or 15 c. c.
6 to 8 ounces Pure water or 180 to 340 c. c.
282 Library of Practical Photography.
770. If the subject has strong contrasts of light and
shadow, use a little less of No. 3 and a little more water than
usual.
771. If the subject is flat and lacking in contrast, increase
the amount of No. 3 and use a little less of No. 2; a few
drops of bromide solution will be beneficial.
772. Keep developing solutions cool and use more water in
hot weather.
773. Do not use a cold developer in cold weather. The
water may be decreased when the temperature is low.
774. For Non-Halation ( double-coated) Plates, use about
one-third more water ; the development will be slower, but
the results will justify the extra time spent in this way.
775. Thk Acid Chrome-Alum Fixing Bath. — Experi-
ence has taught us that negatives obtained with an alkaline
developer are best fixed in a fixing bath having an acid re-
action. We cannot urge too strongly upon our patrons the
use of our acid chrome- alum fixing bath throughout the
year ; it has the following advantages over the ordinary fixing
bath:
No. I. In use, it remains clear.
No. 2. Negatives fixed in it give a uniformly favorable
color for printing, free from spots, streaks and stains.
No. 3. It hardens the film of the negative, producing
quicker drying and preventing excessive intensity incident
to slow drying in a hot room. This is an advantage not to
be overlooked in warm weather.
No. 4. It instantly arrests development.
See formula under title. Fixing, paragraph 802.
776. Pyro and Potash. — (By Hydrometer.')
No. I Solution.
Sodium Sulphite testing sixty degrees.
No. 2 Solution.
Potassium Carbonate testing thirty degrees.
special Instruction for Hammer Plata, 283
No. 3 Solution.
Bnglisb Weights Metric Weights
and Measure. and Meabure.
16 ounres of Pure water or 480 c. c.
15 grains of Oxalic Acid or i gramme
I ounce of Pyrogallic Acid or 30 grammes
To Develop, Take :
I ounce of Solution No. i or 30 c.c
1 ounce of Solution No. 2 or 30 c.c.
y^ ounce of Solution No. 3 or 15 c.c.
8 ounces of water or 240 c.c.
When solutions are made up by hydrometer, the tempera-
ture must be taken into consideration ; for if the hydrometer
is used to test the same solution at different temperatures, there
will be a difference in the reading of the hydrometer scale.
777. A Good Pyro Developer.
No. I
Sodium Sulphite, hydrometer test sixty degrees.
No. 2
Sodium Carbonate, hydrometer test thirty degrees.
To Make No. 3, Take .
English Weights Metric Weights
and Measure. and Measure.
12 ounces of No. i or 360 c.c.
And to this add —
2 ounces of Sulphurous Acid or 60 c.c.
Then add —
I ounce Pyrogallic Acid or 30 c.c.
Lastly add —
1 ounce Pure Glycerine or 30 c.c.
To Develop, Take:
2 ounces of Solution No, i or 60 c.c.
2 ounces of Solution No. 2 or 60 c.c
I ounce of Solution No. 3 or 30 c.c.
8 to 12 ounces of Pure water or 240 to 360 c.c.
In warm weather use more water, in cold weather less.
284 Library^ of Practical Photography^.
778. Pyro-Metol-Tolidol Developer.
(*• This is a good developer ; some think it has no equal." — Eppert.)
No. I
Sulphite of soda testing sixty degrees
No. 2
Is made by mixing together equal quantities of :
Carbonate of Soda testing sixty degrees
Carbonate of Potash testing sixty degrees
No. 3
Water 11 ounces
Pyro }4 ounce
Metol 120 grains
Tolidol 120 grains
Citric Acid 60 grains
I ounce of No. i (sulphite testing sixty degrees).
To Dkvklop, Take:
Water 6 to 10 ounces
No, 1 1^ ounce
No. 2 ^ ounce
No. 3 2 to 4 drams
During the warm weather leave out the carbonate of soda
in No. 2, using the carbonate of potash (testing sixty degrees
by hydrometer ) alone.
779. Metol and Hydroqjjinone Developer.
No.
I
English Weights Metric Weights
and Measure. and Measure.
80 ounces of Pure hot water or 2400 c.c.
I ounce of Metol or 30 grammes
j/^ ounce of Hydroquinone or 4 grammes
6 ounces of Sulphite of Soda (cryst.) or 180 grammes
No. 2
80 ounces of pure water or 2400 c.c.
5 ounces of Carbonate of soda (cryst.) or 150 grammes
special Instruction for Hammer Plates. 285
To Develop, Take:
a ounces of Pure water or 60 c.c.
I ounce of Solution No. i or 30 c.c.
I ounce of Solution No. 2 or 30 c.c.
For those who wish to make only a small quantity of devel-
oper, the following formula will answer :
No. I
English Weights Metric Weights
and Measures. and Measures.
8 ounces of Pure water or 240 c.c.
150 grains of Sulphite of soda (cryst.) or 10 grammes
60 grains Eikonogen or 4 grammes
8 grains Hydroquinone or ^ gramme
No. 2
8 ounces Pure water or 340 c.c.
150 grains Carbonate of Potash (dry) or 10 grammes
To Develop, Take:
2 ounces of Solution No. r or 60 c.c.
I ounce of Solution No. 2 or 30 c.c.
Can be used repeatedly until exhausted.
780. Eikonogen- Hydroqjuinone Developer.
As used on Hammer Plates by prominent photographers.
No. I
English Weights Metric Weights
and Measures. and Measures.
64 ounces of Pure water or 1920 c. c.
I ounce of Eikonogen or 30 grammes
"% ounce of Hydroquinone or 4 grammes
2j^ ounces of Sulphite of Soda (cryst.) . , or 75 grammes
No. 2
64 ounces of Pure water or 1920 c. c.
3)^ ounces of Carbonate of Potash, (dry) or 75 grammes
To Develop, Take :
2 ounces of Solution No. i or 60 c. c.
I ounce of Solution No. 2 or 30 c.c.
286 Library of Practical Photography.
And old developer (solution previously used) in sufficient
quantity to produce best results.
y8i. Pyro and Metol Developer.
No. I
English Weights Metric Weights
and Measures. and Measures.
57 ounces of Pure water or 1710 c, c.
2^ ounces of Sulphite of soda (cryst.). . . .or 75 grammes
1 ounce of Metol or 30 grammes
No. 2
57 ounces of Pure water or 1710 c. c.
2}4 ounces of Sulphite of Soda (cryst.). . .or 75 grammes
^ ounce of Pyrogallic Acid or 8 grammes
No. 3
57 ounces of Pure water or 1710 c. c.
33^ ounces of Carbonate of Potash or 75 grammes
To Develop, Take :
3 ounces of Pure water or 90 c. c.
I ounce of Solution No. i or 30 c. c.
1 ounce of Solution No. a or 30 c. c.
I ounce of Solution No. 3 or 30 c. c.
This developer may be used repeatedly, by adding a little
fresh developer as required.
Keep the used developer in a separate bottle. It combines
the desirable qualities of metol and pyro, and gives an ideal
negative.
783. Another Pyro-Metol Developer.
No. 1
English Weights Metric Weights
and Measures. and Measures.
27 ounces of water or 810 c . c.
I ounce of Pyro or 30 grammes
60 grains of Metol or 4 grammes
No. 2
Carbonate of Soda Testing forty degrees.
special Instruction for Hammer Plates. 287
No. 3
Sulphite of Soda Testing seventy to eighty degrees.
For use, take i ounce each of No. i, No. 2 and No. 3, in 8 to 12
ounces of water, or 30 c. c. each of No. i, No. 2 and No. 3, in 240 to 360
c. c. of water.
DEVELOPING FORMULAE FOR HAMMER
LANTERN PLATES.
783. Pyrocatkchin Solution. — A one-solution, quick-
acting developer, giving black tones.
Boiled or distilled water 5 ounces
Pyrocatechin i2o grains
Bromide of Potash 8 grains
Sulphite of Soda i ounce
Caustic soda (in sticks ) 60 grains
Dissolve each ingredient in the order named.
For Use, Take:
One dram of this stock solution to each ounce of water.
784. EiKONOGEN-HYDRoqyiNONE DEVELOPER : — Warmer
tones.
No. I
Pure water 15 ounces
Sulphite of Soda 6 drams
Citric Acid 15 grains
Eikonogen 90 grains
Hydroquinone 45 grains
No. 2
Pure water 10 ounces
Caustic soda (in sticks) 60 grains
Bromide of Potash 60 grains
For Use, Takk :
Solution No. i 2 ounces
Solution No. 2 I ounce
288 Librarx) of Practical Photography.
785. The fixing bath must be fresh and clean. Use about
six (6) ounces hypo to the pint of water, or use our acid
chrome-alum fixing bath.
786. The plate must be thoroughly fixed and thoroughly
washed. When the last trace of silver bromide disappears,
consider the plate only half fixed.
787. It is advisable (after washing well) to use a clearing
solution, even if there is no stain apparent.
788. The plate must be well washed before puttmg it into
the clearing solution.
789. The tone of a lantern slide made on these plates may
be decided either by the length of exposure and the develop-
ment, or by an after- process.
790. The rule of development toning is that prolonged ex-
posure and a heavily restrained developer give warm tones.
The restrainer generally used is a ten-per-cent. potassium bro-
mide solution.
791. HvDROQjyiNONK DEVELOPER. — (jFor black tones.')
English Weights Metric Weights
and Measures. and Measures.
20 ounces Distilled water or 1000 c. c.
60 grains Hydroquinone or 7 grammes
2 ounces Sulphite of Soda (cryst.) . . or 100 grammes
6 ounces Carbonate of Soda (cry St.). .or 300 grammes
40 grains Bromide of Potash or 4.6 grammes
( Use without diluting.)
Dissolve the hydroquinone in the water and add the other
chemicals in the order given.
792. If the plate is properly timed, development will be
complete in about two minutes. This developer can be used
for several plates by adding a little fresh developer to that
used after each development.
793. Some lantern slide experts prefer to slightly over-
develop, and then after fixing and washing to reduce the slide
to the proper density; this method produces very crisp, clear
slides. Those wishing to try this method should use our How-
ard Farmer reducer. This reduction can be done by daylight.
Wash well after reducing and rinse in absolutely clean water
before setting up to dry.
special Instruction for Hammer Plates. 289
794. Hammer's Dry Powder Developer. — (JFor the
amateur.^ (Factor 8.) Is compounded with accuracy from the
best of chemicals insuring good results to the user.
795. The only caution that is necessary is for the user to
be sure that both powders are entirely dissolved; then if the
plate has the correct exposure (or near it ) a good negative
will result.
796 We do not advocate this developer in preference to
those that may be prepared from our published formulae, if
good chemicals are used ; but for those who do not wish to
make up stock solutions, or when going on a trip they wish
to carry the developer in a form that shall not cause damage
to other goods in case of breakage, this is just the developer
that will fill the bill for this purpose, as a trial will convince
you. There are none better and we have found none as good
(in this class).
797. This developer is enclosed in sealed glass tubes, six
tubes in a box. Each tube will make from five to seven
ounces of developer. (The more water used the softer the ef-
fect.)
798. Negatives. — Negatives suitable for all the different
printing processes — carbon, platinum, albumen, collodion, gel-
atine, etc., — may be successfully and easily made on the Ham-
mer Plates by a slight modification of the developing solu-
tions.
799. Washing After Development. — In all cases it is
desirable to wash the plate for at least two minutes before
fixing it.
800. Fixing. — The plain fixing bath is a solution of hypo-
sulphite of soda, of a strength of about five (5) or six (6)
ounces to the pint of water. A fully saturated solution diluted
with an equal quantity of water is of about this strength.
The plate should be left in the fixing bath for several minutes
after it appears to be cleared ; as long as it took to fix would
not be too much. Neglect of this precaution may lead to the
formation of insoluble compounds in the film, which, although
not visible at first, may in time result in stains or even total
decay of the negative. Commercial hypo-sulphite of soda
290 Library of Practical Photography^.
usually contains foreign matter, which, if allowed to remain
m the solution, will cause spots on the negative. Filter before
use. If the regular fixing bath is too strong and not stirred
before use, it will at times cause parallel lines on the negatives
that were fixed in grooved fixing boxes.
A cool fixing bath can be prepared by dissolving a fresh
lot of hypo for each batch of plates. This is of benefit during
the hot weather.
8oi. Acid-Fixing Bath. — Owing to the quality of the
water in some localities, some workmen prefer an acid-fixing
bath. The following is good and remains clear (mix in order
given) :
Water (about) 120 ounces
Sulphuric Acid 3 drams
Sulphite of Soda 4 ounces
When dissolved, add :
Hypo-sulphite of soda 2 pounds
Water to make 160 ounces
802. Acid Chrome-Alum Fixing Bath. — This kind of a
bath has been in use for years and is preferred by many ( mix
only in the order given) :
Water (about) 100 ounces
Sulphuric Acid 3 drams
Sulphite of Soda 4 ounces
When dissolved, add :
Hypo-sulphite of Soda 2 poimds
Dissolve, and then add:
Chrome-alum, from i to 2 ounces, previously dissolved in 20 ounces
of water. Then add water to make 160 ounces.
803. Acid-Fixino Bath. (F'or Lantern Slides.) — An
acid-fixing bath for lantern slides is made as follows (chemi-
cals must be mixed in order given only) :
special Instruction for Hammer Plates. 291
Sulphite of soda, ^ ounce ; dissolved in i ounce of water,
and then add 30 drops of hydrochloric acid. Stir well. In a
separate vessel, dissolve :
Hypo-sulphite of soda, 4 ounces, in 20 ounces of water.
When the hypo is all dissolved, add the acidulated sulphite
solution to the solution of hypo. (Not the reverse.) The
whole being gently stirred during the mixing.
804. Alum. — Alum is frequently employed for the pur-
pose of hardening the film, especially in hot weather, but its
use is attended with considerable danger to the negatives, as
alum and hypo mutually decompose each other with the pro-
duction of new substances, which endangers the natural life
of the negative. If used as given in our acid chrome-alum
fixing bath it is all right.
805. Formaline. — Formaline, or Formaldehyde, is a gas
which dissolves to a large extent in water. A solution of the
strength of forty per cent, is sold commercially. This liquid
diluted with from ten (10) to twenty (20) parts of water (i
ounce to 20 ounces), makes a bath which may be used to harden
the gelatine film, and is easily washed out and not likely to do
any harm. After the plate is developed and then washed for
two or three minutes, it is placed in the above mentioned solu-
tion (i to 20) for three or four minutes. The plate should
then be rinsed and placed in the hypo bath as usual. After
fixing, the film will be found so tough and insoluble that the
negative may actually be washed in water hotter than the
hand can bear, without any sign of softening. Negatives so
treated dry much more quickly than when treated otherwise.
Plates slightly washed after fixing may be treated with Form-
ahne (i to i6)if preferred, and then washed as usual.
806. Washing After Fixing. — It is desirable that wash-
ing after fixing be quickly and thoroughly done. If running
water be available, an hour is long enough ; when the water
supply is limited, the plate may be washed in a flat dish, fre-
quently rocked, for five minutes or so ; the water being then
drained off and a fresh quantity added, and the process
repeated until the plate has had a half to three-quarters of an
hour washing. When left to wash in running water, it is
292 Library of Practical Photograph}^.
better for the plate to be placed vertically in a grooved box
than to lie in a flat dish, thereby avoiding any sediment which
is likely to settle on and stick to the soft gelatine surface.
When a plate has been sufficiently washed, it is well to hold
it (face upward) under the tap of running water and lightly
wipe over the surface with a pad of filter cotton, in order to
remove any sediment which may have settled on the film from
the washing water. To prevent sand or rust from striking the
negatives while washing them, tie a piece of cotton flannel
over the faucet.
807. Drying the Negatives. — Plates are best dried in
a moderately warm room, the temperature of which should
not vary much, with good ventilation. They should not be
placed too close together. A plate must never be laid in the
sunlight to dry, as this may melt the film, cause transparent
holes, and, if nothing worse, will increase the intensity. In
cold weather do not allow the negative to get too cold while
drying; this not only retards the drying, but in case the mois-
ture therein should freeze, it will cause mottled spots. If the
negative is partly dry and then removed to another room which
is much warmer or colder, it will cause a difference in the
intensity of the part to dry last. If a negative be wanted in
a hurry, it may be quickly dried by laying it for ten minutes
( afier thoroughly washing) in a bath of alcohol, then it will
dry rapidly. If dried in this way the negative must first be
very thoroughly washed, for if any hypo be left in the film,
an insoluble white deposit may be formed, which cannot after-
wards be removed.
808. Halation. — Halation is the spreading of the strong
lights of a negative and consequent encroachment upon the
shadows. In a view negative including a bright sky it is
generally found, on development, that the extreme edge of the
plate above the sky, which was protected by the rebate of
the dark slide, does not remain clear, although the other
three edges may do so, the strong light of the sky having
spread beyond its proper boundary. When a picture is taken
of the dark interior of a building including a window, the
special Instruction for Hammer Plate's. 293
light of the latter often seems to spread and form a wide
blur all around. (Can be remedied by local reduction.)
In the ordinary negative the effect of halation is scarcely
apparent ; but, nevertheless, it is there more or less generally,
and is detrimental to the fine details. Halation is due chiefly
to light which has passed through the film and been reflected
from the back surface of the glass plate. It is also, to a minor
extent, caused by a lateral spreading of light from particle to
particle of the silver bromide in the film. Some plates are
more liable to halation than others ; this depending on the
opacity and other characteristics of the film. The Hammer
Plates, even when not backed, are notably free from it ; but
the Hammer Aurora Double- Coated (Non-Halation) Plate
is prepared especially to prevent halation. We recommend
their use, especially for interiors, landscapes and marine views,
as well as for groups and white draperies. Expose for the
darkest shadows and use a rather dilute developer.
809. We also furnish a backing, "Acme Halation De-
stroyers," which is a good article for sticking in optical con-
tact with the glass. It helps to overcome the halation effect.
We also furnish plates backed with this medium when so or-
dered.
ORTHOCHROMATIC SCREENS AND PLATES.
810. A general misconception still prevails concerning the
use of Orthochromatic Plates with or without a screen.
The relative brightness of the colors of an object as repre-
sented in an ordinary photograph is very different from the
relative brightness of the same colors as seen by the eye.
This is due to the fact that all photographic plates including
the very best of the so-called Orthochromatic (Hammer's), are
enormously more sensitive to the blue and violet than to red,
yellow and green.
In the early days of these plates, some persons had the idea
that Ortho plates could not be used at all without a screen —
try a few and see.
There is some advantage with Orthochromatic Plates in
color rendering without the screen, if the violet and blue do
294 Library of Practical Photography.
not predominate. All plates have excessive sensitiveness for
violet and blue. Orthochromatic Plates show this tendency
also. The use of the screen is to cut off the excess of the ac-
tinic light.
A screen gives better rendering of gradation, but it pro-
longs the exposure. If, however, the conditions under which
the photograph is taken demand a short exposure, the screen
may be abandoned.
Much has been said about adjusting the screen to the color
sensitiveness of the plate ; of course, this is important in such
exact work as three-color printing necessitates, but with land-
scape and all ordinary objects that are to be photographed, less
exactitude is permissible.
HAMMER'S ORTHOCHROMATIC PLATES.
(Three Grades.)
Slow — Extra Fast — Non-Halation.
8ii. The product of years of chemical research, which
have produced a plate that is sensitive to orange, yellow, green
and the ordinary reds.
812. These plates have been much improved within the
last year. Their color sensitiveness has been greatly increased.
813. The value of this special sensitiveness is very appar-
ent. In view work, where there are clouds and colored foli-
age, or work embracing great distance, the finer details are
retained. Draperies are reproduced in their true color values.
Auburn hair will not be reproduced as though it were black.
Freckles are less noticeable. Blue eyes will not be reproduced
as almost white.
814. The day is not far distant when nearly all of the
plates used will be color sensitive.
815. The Extra Fast Orthochromatic is slightly faster than
the regular Extra Fast Plate.
816. The Non-Halation Orthochromatic combines all the
advantages of a double-coated plate with those of the color
sensitive plate, and is an exceptionally good plate.
special Instruction for Hammer Plates. 295
817. The Slow Orthochromatic has a high degree of color
sensitiveness, and we recommend it for use where time can be
given.
818. In bright light a yellow screen is an advantage.
819. We make a Special Red sensitive Plate to order
which is sensitive to the entire spectrum, and must be handled
with great care ; this plate is for three-color work.
HAMMER'S SPECIAL EXTRA FAST.
820. There being a limited demand in exceptional cases
for a plate that is still faster than our Extra Fast, we have
placed this Special Plate on the market to meet this demand.
821. This plate is of special use during the dark winter
months, and for objects where the shortest exposure possible
must be given.
822. They are invaluable for flash-light exposures, ex-
tremely short snap-shot exposures, etc.
823. In the Hammer Special we retain the fine grain of
the slower plates, even with this extreme rapidity,
824. In all ordinary cases our Regular Extra Fast Plate
will be found rapid enough for all requirements, but we offer
this Special Plate for special cases where nothing else will do.
HAMMER'S X-RAY PLATES.
825. In order to get the best results in this kind of work,
it is necessary to have a specially prepared plate and a spe-
cially prepared developer.
826. Our X-Ray Plates (^ dozen in a box) are packed in
envelopes made of chemically pure paper.
827. All plates must be kept well out of range of the
X-Rays, or they will be ruined.
HAMMER'S (DRY POWDER) X-RAY DEVELOPER.
828. This preparation is for the development of Hammer
X-Ray Plates that have received X-Ray exposures.
829. It works rather slowly, but allows shorter exposure
of the plate and will give a negative of more intensity and
II — 17
296 Library) of Practical Photography^.
without sacrifice of the shadows, than will a developer made
by any other formula.
830. This developer should not be used for ordinary photo-
graphic plates.
HAMMER'S EXTRA FAST PLATES.
831. Specially adapted for use in the studio, for general
photographic work where short exposures are necessary, also
for the hand camera and instantaneous exposures.
832. The Hammer plates do not require as strong a devel-
oper as that generally recommended for other plates.
833. Consequently the best results are obtained by using
our formulae, as published. If more delicate effects are de-
sired, add more water in diluting the developer for use ; it
causes a little slower development, but its advantage will be
seen in the finished negative.
HAMMER'S FAST PLATES.
834. This brand of plates is intermediate in rapidity, be-
tween Hammer's Slow and Hammer's Extra Fast, combining
the great latitude of the Slow Plate with enough rapidity for
all ordinary purposes, except where a very short exposure is
required or the light is not good.
835. A large number of photographers use this plate for
view work, while many commercial workmen prefer it to all
others. The grain is fine and the latitude good. Any degree
of softness or contrast may be produced on this plate, by no-
ting the principle mentioned in the article about Slow Plates.
836. If the Slow Plate is too slow and the Extra Fast is
too rapid, then this is the plate that you want — easy to work
and an ideal plate, unless you wish to make snap-shots, in
which case see article regarding Hammer's Extra Fast.
837. For the benefit of the beginner, we give a table show-
ing the approximate exposure required on Hammer's Extra
Fast Plates, on various subjects and in lights of various
strength. This is (10 a. m. to 2 p. m.) in May, June and
special Instruction for Hammer Plates. 297
July. In other months (and earlier and later in the day) the
light is not so strong.
838. Of course, the temperature of the developer and the
quality of the lens bring in variations that we have not space
to consider here, but we wish to give some idea about the ex-
posure required on different subjects under various conditions
of light. (Use No. 8 diaphragm.)
839. With the Orthochromatic Extra Fast Plate, without
a screen or a ray filter, the exposure is the same as given
below. If a screen or a ray filter is used the exposure will
have to be increased from four to eight times, according to
the darkness of the filter.
840.
Exposure Table for Hammer Ex-
tra Fast Plates, in
Subject —
Clouds
Snow, sea and sky — dis
tant view
Semi-distant views and light
objects
Average scenes, near views
and buildings
Groups, dark objects, por-
trait — out-of-doors . . .
Views — heavy foliage in
foreground
Wood and badly-lighted
river banks
Intense
Sun
Bright
Hazy
Dull
Part of a Second
1-800 1-500
1-400 1-250
1-200 I -125
i-ioo 1-64
1-50 1-32
1-25 I -16
i-io 1-8
Very
Dull
1-400
1-250
1-200
1-200
1-125
I-IOO
l-IOO
1-64
1-50
1-50
1-32
1-25
I-2S
I-I6
1-12
I-I2
1-8
1-4
1-6
1-4
1-2
HAMMER'S SLOW PLATES.
841. This brand of plates allows great latitude in the ex-
posure; has exceptionally fine grain, and is what its name
implies — Slow, being about one-fourth the rapidity of Ham-
mer's Extra Fast Plate.
842. It is just the right rapidity and quality for view
work, where there are no moving objects, such as the ordinary
views that are taken by professional and amateur photog*
rapbers.
298 Librar]) of Practical Photograph)).
843. This plate is extensively used:
J^or copying
For process work
For button 'work
For commercial 'work
and any photographic work that does not require a short ex-
posure.
844. These plates, when developed with a normal devel-
oper and the development carried reasonably far, will give
strong negatives with clear shadows.
845. But if a dilute developer is used, one can get a fine
soft chemical effect.
HAMMER'S LANTERN SLIDE PLATES.
846. These plates are suitable for making slides either by
contact or reduction.
847. These plates are coated on glass specially made for this
purpose, which is thin and free from defects. The ordinary
negative glass, although excellent for the purpose, is not suit-
able for a lantern slide, as a defect that is too small to be de-
tected by the eye will be very noticeable when enlarged by
the lantern.
848. Many of our novice friends make positives from their
negatives on these plates, as they reproduce all there is in the
negative ; nothing is lost as is the case with paper prints.
849. Our lantern emulsion is a model for fine grain, clear-
ness and freedom from defects in general.
850. This plate will give rich, warm tones, or engraving
black at will, with absolute clear glass effect in the high-
lights.
851. Slides that are to be shown with a very strong light
— electric oxy-hydrogen — should be made more dense than
those to be shown with an oil light.
special Instruction for Hammer Plates. 299
HAMMER'S TRANSPARENCY PLATES.
( The Ideal Pictures. )
852. Are specially prepared of a slow fine grain emulsion,
giving clear glass effect for the highlights and crisp, brilliant
shadows of ideal gradation, producing the very finest positives
on glass.
853. A fine positive on glass, such as can be made on
Hammer's Transparency Plates, reproduces all that there is in
the negative ; nothing is lost, as in the case when paper prints
are made. These plates may be used for contact work, the
same as in using developing paper ; using a plate the same
size as the original negative, or, by using a mask of the black
paper, a larger or smaller plate may be used.
854. By using the enlarging camera one can take their
small negatives and produce a large transparency of almost
any size.
855. These plates are used quite extensively for this pur-
pose, but as their advantages become more generally known,
the demand for them continues to increase.
856. Made in all shapes and sizes.
Odd sizes made to order.
857. These plates are about four times the rapidity of the
Hammer Lantern Slide Plates.
858. Coated on specially selected glass.
HAMMER'S NON-HALATION.
Is a Double- Coated Plate.
859. The cleaned glass is first coated with our Slow emul-
sion and dried as usual ; then each plate is examined for any
possible defects. The perfect plates are returned to the coat-
ing-room, and there receive a second coating, but this time it
is of our regular Extra Fast emulsion. They are then returned
to the drying-room, dried, and the next day again examined.
Those having no defects are then packed for the market.
860. One can readily see the immense advantage this plate
has over a single-coated plate for general work as where great
contrasts are to be photographed.
300 Library of Practical Photography.
86i. Expose (time) for the shadows, time the exposure
for the outer film; the under or slow film will take care of the
high-lights. To get the best results these Non- Halation
plates should be developed with a rather dilute developer —
give the under film a chance to show its quality. Fix, and
wash a little longer than usual.
WEIGHTS AND MEASURES
Fluid Measure.
862.
60 minims I fluid drachm
8 drachm i ounce
16 ounces i pint
8 pints I gallon
All chemicals are usually sold by avoirdupois weight, in
which there are 437^ grains to the ounce, and 16 ounces to the
pound. This is the ounce used in all of our published formulae.
863. Stripping Film.
(Removing film quickly from glass.)
A
Sodium Fluoride 6 grains
Water 4 ounces
B
Sulphuric Acid 6 drops
Water i ounce
Both solutions can be used until exhausted. Place the
negatives in solution A for a couple of minutes, and then
place directly in solution B. After another couple of minutes
raise the film with the finger from one corner; it will soon
leave the glass. Very good in the case of broken negatives,
for transferring the film onto another glass. In this case
place the negative (before stripping) in a chrome-alum bath,
made up i ounce chrome-alum and 20 ounces water, for one-
half hour. Then wash well and proceed to strip. (Another
satisfactory method is given in Vol. X, page 331.)
CHAPTER XXII. .
Wet Plate Process.
864 Following closely on the heels of the earliest
method of taking portrait photographs — that is, on a sil-
ver plate by the Daguerrean process — came the discovery
of the use o\ collodion as a transparent vehicle for holding
the salts sensitive to light. The Daguerreotype had the
disadvantage that the image was reversed (although a
positive) and was not reproducible, so was speedily dis-
placed by the newly discovered wet collodion process,
which gave results equal in fineness and gradation to any
produced by the modern dry plates. It was styled the
wet plate process, because it had to be used in a wet,
freshly-prepared condition to retain its sensitiveness. It
was not until some time later that a dry sensitive collodion
emulsion was devised, and this again was speedily dis-
placed by the gelatin emulsion of the dry plate as we
know it today.
865. The original method of the wet plate process
was to flow a collodion film containing metallic iodides
on a sheet of glass, and then to sensitize the film in a
solution of nitrate of silver. This formed iodide of silver
salts, which were more sensitive than nitrate of silver salts.
The exposure was made while the plate was still wet from
immersion in the silver bath, and then developed in a
solution of pyrogallic and acetic acids, being subsequently
fixed in hypo. This process is essentially the same as the
wet plate process still in use.
866. Application of Wet Plate Process. — ^While the
wet plate process is not a difficult one, yet for studio and
general photographic work it has outgrown its usefulness.
However, there are special departments of photography
301
302 Librarxf of Practical Photography.
for which the wet plate is indispensable and is better
adapted than its rival, the dry plate. For instance, for the
photographing of large drawings, maps, etc., the wet plate
gives the best results both on account of its greater econ-
omy when large plates are used and because clear lines
and dense backgrounds can readily be obtained. This
process is, therefore, principally employed by the govern-
ment, where thousands of maps and drawings are to be
reproduced, and in large commercial studios where similar
work must be reproduced.
867. The wet plate process is also used for certain
kinds of technical work, such as the making of negatives
for process work for photo-engraving, etc. It is also used
in making enlarged negatives, lantern-slides, and for micro-
scopic work. For the latter mentioned purposes it has
two distinct advantages over the modern dry plates — first,
its cheapness, and second, the possibilities of obtaining
greater density of deposit, together with the extreme clear-
ness of shadows. Still another reason, more especially for
microscopic and lantern-slide work, is the possibility of
producing the extremely fine grain, which is an advantage
where fine detail is required.
868. The manufacturers of the dry plate of today
are endeavoring to imitate the qualities of the wet plate,
and in many instances they have met with success ; but,
owing to the difference in expense between the two, the
wet plate will always hold its own for commercial purposes.
869. In the early days of the wet plate process, the
photographer was not only compelled to prepare his own
collodion, but also the pyroxyline (gun-cotton) from which
the collodion was made. Today, however, collodion can
be purchased already prepared for use, and while large
consumers of collodion prepare their own chemicals, yet
the making of gun-cotton has been dispensed with and this
product is bought ready for use from the supply dealers.
870. Dark-Room. — The first requirement for the wet
plate process is the dark-room. While any ordinary pho-
tographic dark-room will do, yet, as the wet plate is less
Wet Plate Process. 303
sensitive to light than the modern dry plate, a much
stronger light may be employed for manipulation of the
wet plate than would be safe to use for the dry plate. A
light which would be sufficiently safe for the development
of bromide papers would be perfectly safe for the manipu-
lation of the wet plate. Usually, one thickness of post-
office paper over an ordinary light will be found perfectly
safe. The yellow or amber color will be found better than
the ruby light. While a less diffused light may be em-
ployed for the manipulation of the wet plate, a dark-room
absolutely free from white or actinic light must be used.
871. Dark-Room Equipment. — The dark-room should
be equipped with a sink of sufficient size to allow of plenty
of room for the developing directly over the sink. At one
end of the sink you should prepare a place to receive the
siher bath. This bath should be so located as to project
only a trifle above the top of the sink itself. The top of
the bench on which the silver bath rests should be covered
with blotting paper, to take up and absorb any of the drip-
pings that may fall from the wet plate coming direct from
the silver bath.
872. For experimental purposes and small work, such
as the making of lantern-slides, etc., one may use an ordi-
nary clean tray for sensitizing the plate, but this will not
prove very convenient, as a clip or dipper of some kind
should be employed for the handling of the plate. The fin-
gers must not come in contact with the silver solution,
as this will stain them black on exposure to light; there-
fore, the regular silver bath dish with dipper for handling
the plate is recommended.
873. At the opposite end of the sink you should have
your fixing bath arranged in the same manner as the silver
sensitizing bath. Each bath should be provided with a
rubber dipper, upon which the plate is placed and carried
to and from the bath. A shelf should be placed directly
over the sink for holding the collodion bottles, also your
developing and sensitizing solutions.
874. Chemicals Required. — You will require negative
304 Library of Practical Photograph'^.
collodion, a silver sensitizing bath, fixing bath, developer,
also intensifying and reducing chemicals.
875, Apparatus Required. — While the apparatus for
the wet plate process is practically the same as that used
for the dry plate, yet there are a few additional important
parts necessary. The lens, camera and camera-stand may
be the same as for the dry plate, yet the plate-holder for
the camera is slightly different in construction. The cur-
tain-slide, or what is usually styled the Benster plate-
holder, is used; but, owing to the fact that there are some
drippings of silver from the wet plate, which would drop
onto the wooden guides of the plate-holder and very soon
corrode them, special silver posts are used in the guides,
and in addition to these silver posts, on the bottom guide
there is attached a glass trough to catch the silver drip-
pings from the plate. Aside from this the plate-holder is
exactly the same as that used for the dry plate.
Illustration No. 28
Silver Bath
See Paragraph 876
876. In addition to the plate-holder, two large glass
bath receptacles will be necessary, one to be used for your
silver sensitizing bath and the other for your fixing bath.
While you may construct such a bath dish, it is much
cheaper in the end to purchase the regular vertical glass
baths made especially for this purpose, which can be ob-
Wet Plate Process. 305
tained from any photographic supply house (See Illustra-
tion No. 28.) These glass baths should be large enough
to hold the largest plate that you will use. They are manu-
factured in regular sizes from 5x7 to 21 x 26 and are fur-
nished fitted in a wooden box, or without, just as you de-
sire. The most convenient bath is that furnished with a
wooden box having a hinged cover, thus enabling you to
keep your bath covered at all times, free from dust.
877. Dippers. — For the purpose of lowering the plate
into the silver bath, or into the fixing bath, you should
provide yourself with two hard rubber dippers. These are
so arranged that the plate rests on the small tips attached
to the bottom of the dipper. There is still another style of
dipper, made of German silver, which will answer every
purpose, but it is not generally in use in this country.
878. Bottles. — You should provide yourself with a
number of bottles large enough to hold the contents of
your silver bath. Two or three of these bottles should be
kept on hand, and two silver baths should be prepared —
one being placed in the sun while the other is in use. The
object of sunning the bath will be more fully described in
a later chapter.
879. Besides the large bottles for the silver bath, you
should provide a few bottles for your collodion, also for
the developer. Collodion bottles should be provided with
small necks, permitting of as little area as possible for
exposure to the air when the stopper is removed. A small-
necked bottle is also more convenient for use in flowing
the plate. The developer bottle should be wide-mouthed.
The bulk of your stock solution should be kept in very
large bottles, while the developer ready for use may be
kept in smaller bottles. Bottles should also be provided for
your intensifying and reducing solutions.
880. Glass. — A good quality of sheet glass, carefully
selected, free from bubbles, scratches and other defects,
will answer for the smaller sizes. For large sizes and im-
portant work, either flat crown or patent plate-glass should
be used. The former is preferable.
306. Library of Practical Photography.
88 1. Negative Collodion. — In preparing the negative
collodion, we generally divide the process into two sec-
tions. First, we prepare what is known as plain collo-
dion, which is made up of ether, alcohol and negative cot-
ton (gun-cotton). The plain collodion alone is not suitable
for negative work, but it must be iodized before it is ready
for use. The object of the distinction between plain collo-
dion and iodized collodion is as follows:
882. Where much use is made of the wet plate proc-
ess, and special results are required for different kinds of
work, the formula for the collodion requires changing. In
some cases more detail is required, in others more contrast
is necessary; consequently, this altering may be done in
the iodizing of the collodion. Many commercial users pre-
pare their plain collodion in large quantities and then iodize
portions of it for different purposes, and place each in a
separate bottle; in consequence, they have different for-
mulae to be used on different classes of work — thus the
object of the terms plain collodion and iodized collodion.
883. Formula for Negative Collodion. — Note: For
the convenience of the beginner, in the following formula
we supply a quantity of 20 ounces of collodion. Any larger
or smaller quantity may be prepared in the same
proportions :
884. Plain Collodion.—
Alcohol 10 ozs.
Ether 10 ozs.
Gun Cotton (Neg. Cotton) 120 grs.
885. Preparing the Plain Collodion. — A simple method
for preparing the collodion is as follows : Dissolve 6 grains
of gun-cotton (negative cotton) to every ounce of equal
quantities of alcohol and ether. In preparing the above
formula for 20 ounces of collodion you would proceed as
follows :
886. Place in a 32-ounce narrow-necked bottle, 120
grains of negative cotton. It will be found necessary to
puU the cotton in small threads in order to insert it in
Wet Plate Process. 307«
the narrow neck of the bottle. After all the cotton has
been placed in the bottle, add 10 ounces of alcohol and 10
ounces of ether. Shake until the cotton is entirely dissolved.
This constitutes your plain collodion.
887. Iodizing the Collodion. — The collodion is iodized
by adding to the above plain collodion solution:
Iodide of Cadmium 10 grs. .
Iodide of Ammonium 60 grs.
Bromide of Ammonium 30 grs.
Shake until all ingredients are dissolved. The collodion works
best when allowed to stand for a day to ripen before use.
888. It may become necessary at times to change the
proportion slightly. For example, in cold weather you
may slightly increase the ether and proportionately de-
crease the alcohol. By changing the proportions of iodide
and bromide more density or more detail may be produced
— less bromide will give more contrast, more bromide will
give more detail, etc.
889. Preparing the Silver Sensitizing Bath. — The
preparation of the silver bath is, practically speaking, a
very simple matter, yet there are certain points which are
important and must be remembered. The bath must be
either neutral or acid, never alkaline, and the amount of
acidity or neutrality is governed entirely by the compound
used in forming the collodion. For example: If iodide
alone is used, so that the collodion is simply an iodized
collodion and the sensitive salt in the film consists
wholly of silver iodide, then the bath may be in a neutral
state. If the collodion has been bromo-iodized according
to the formula given above, the bath must be slightly acid.
It is advisable for the beginner to use the bromo-iodized
bath, as given above, and prepare the sensitizing silver bath
acid, using nitric acid, C. P., for the purpose. Nitric acid
will prevent spontaneous or independent reduction of the
silver, thus keeping the shadows clear and free from chemi-
cal fog.
890. The quantity of silver solution to be prepared
308 Library of Practical Photograph}).
will depend entirely upon the size negatives to be made ;
in other words, prepare sufficient to fill the glass receptacle
in which the plates are to be sensitized. The following
formula will be found to give excellent results and will make
sufficient solution to cover an 8 x 10 plate :
Pure Nitrate of Silver, crystals 6 ozs.
Distilled Water 80 fluid ozs.
Nitric Acid, C. P 8 minims.
891. Strength of Silver Bath. — The proper strength
of the silver bath should be anywhere from 45 to 50 grains
of silver to the ounce of solution. The simplest method
for testing the bath is with the hydrometer, which will
give you an accurate test of your solution. When the bath
falls below 45° the strength should be increased by the
addition of a few grains of nitrate of silver crystals until
it registers the proper strength. Should it be too strong,
it may be diluted by the addition of distilled water until
it tests the required strength.
892. Iodizing the Silver Bath. — All fresh made silver
baths will require iodizing before use, otherwise they will
produce fog in the negative. To iodize a bath proceed as
follows :
893. Flow a glass plate with the regular iodized collo-
dion, place it in the silver bath, and allow it to remain
there for several hours. No harm will be done to allow
it to remain over night in the bath.
894. Testing Bath. — After the bath is iodized it should
be tested with blue litmus paper, which paper should
turn red almost instantly upon entering the bath. With
the bath testing acid being iodized with the collodion-
ized plate, it should then be filtered ready for use. A
simple way to filter the bath would be to prepare a large,
clean bottle. Place a piece of absorbent cotton in a glass
funnel, first wetting the cotton with distilled water. Place
the funnel in the bottle and pour the silver bath into the
funnel, allowing it to filter slowly into the large bottle;
then rinse out your silver bath dish, to receive the filtered
Wet Plate Process. 309
solution. After all the solution is filtered into the bottle
transfer the solution into the silver bath, when it is ready
for use.
895. The Developer. — For the developing of the wet
plate numerous developers are used. These, however, un-
like the developers for the modern dry plate, contain no
accelerator, but work in an acid state. They consist merely
of a reducer dissolved in water. In order to get the de-
veloper flowing evenly it is sometimes necessary to add
a small quantity of alcohol.
896. Formula for Developer. —
Ferrous Sulphate 2 ozs.
Restrainer (glacial acetic acid) 1 oz.
Water 40 ozs.
Alcohol in sufficient quantity to make the solution flow freely.
Usually V2 ounce is sufficient.
897. Another Good Developer. —
Ammonium Sulphate of Iron 1% ozs.
Glacial Acetic Acid 1V4 ozs.
Water 32 ozs.
Alcohol 2 ozs.
Note. — The formula for this developer calls for small quan-
tities only when preparing your developer. However, a gallon or
more should be made up at a time and prepared in the above pro-
portions. The amounts given in the formula will be sufficient for
experimental purposes.
898. Fixing Bath. — The fixing bath is composed of
cyanide of potassium in approximately the following
proportions :
Cyanide of Potassium 1 oz.
Water 30 ozs.
899. Caution. — Cyanide of potassium is a deadly
poison. Both the bottle containing the cyanide crystals
and the cyanide solution should be labeled and kept out
of reach of children. Where the hands are scratched or
contain any sores, they must never come in contact with
cyanide, otherwise the system might become poisoned.
Extreme care must be used in handling the plate in this
310 Library of Practical Photograph'^.
bath, and the fingers should be kept from the solution by
using a rubber, glass or silver dipper.
900. In place of cyanide of potassium, the following
formula can be used for fixing :
Hyposulphite of Soda 5 ozs.
Water 30 ozs.
901. Washing Glass to be Used for Negatives. — In
order that you may be sure that the glass employed is
chemically clean, place it in a solution of caustic soda or
potash, for say five minutes. When the glass is coated with
film — possibly an old exposed negative — it must remain in
the potash for a number of hours, and for this purpose you
should have an earthen dish or a solid rubber tray, one
large enough to receive a number of plates at one time.
902. Another method for cleaning old dry plates for
wet plate work, is to make up a strong solution of com-
mercial sulphuric acid, placing the plates in this solution. It
is advisable to wear rubber gloves when handling the plates.
Where perfectly clear glass is used, a few minutes' soaking
in the soda or potash will be found sufficient. After the
plates have become thoroughly rinsed and cleansed, whether
old or new, they should then be placed in a 10% solution
of commercial nitric acid and allowed to remain for about
an hour; finally, carefully rinse and set in the negative
rack to dry.
903. Preparing the Plate to Receive the Collodion. —
When dry, the plate is usually ready to receive the collo-
dion; but, while the collodion may be applied direct to
the glass plate without any previous preparation, there
are cases where the collodion will not readily adhere to the
plate. Should you meet with such difficulty it will be
advisable to prepare the plate with albumen before collo-
dionizing it.
904. Albumenizing the Plate. — Prepare the albumen
as follows : Place into a clean dish 32 ounces of pure
water. Add to this the white of one tgg. Beat the Qgg
well, mixing it with the water. Then add 10 to 15
Wet Plate Process. 311
drops of aqua ammonia, and again stir well; then filter
into a clean bottle. To albumenize the plate you flow
the albumen on the plate exactly the same as you collo-
dionize it. (See Paragraph 906.) The plates are, of
course, thoroughly cleansed and dried before this is done,
and just before the albumen is applied the plate is care-
fully dusted with a camel's-hair duster. A sufficient number
of plates for a day's work may be albumenized at one time,
and after albumenizing they are placed in a rack to dry,
in a place free from dust or fumes. The albumen must
be thoroughly dry before applying the collodion. It is
advisable to try collodionizing the plate without albumeniz-
ing it. Should the film slide or break from the plate you
should apply the substratum coating (albumen) to another
sheet of glass, then collodionize it.
905. Collodionizing or Coating the Plate. — Assuming
that the collodion has been prepared properly and has had
an opportunity to ripen, that the silver bath has been made
up according to instructions, and that the plates have
been washed and dried ready for flowing on the collodion,
you first take a plate from the rack, examine it and see
which is the concave and which the convex side. This you
can judge by placing the plate in such a manner that you
can sight along its edge. The side which curves upward
is the concave, and this is the side which should be coated.
Catch the plate, by the lower left-hand corner, between
the first and second fingers of your left hand, allowing the
extreme corner to rest against the thumb. In this way
you will have a firm hold of the plate and can tip it to any
angle and in any manner you desire.
906. Another method is to place the plate on the tips
of the fingers and thumb, separating the fingers slightly so
the plate will be well balanced on the hand. Next, care-
fully dust the plate with a camel's-hair brush ; then with
your right hand take up your collodion bottle and pour a
small pool of collodion on the center of the upper part of
the plate. Tip the plate a trifle, flowing the collodion to
the top right-hand corner, then to the top left-hand comer,
312 Library of Practical Photography.
next to the bottom left-hand corner, and finally to the
bottom right-hand corner. The excess collodion should
then be drained carefully back into the bottle. As soon as
the plate has ceased to drip, replace the stopper in the
collodion bottle. The collodion bottle must always be
kept tightly stoppered when not in use, as the ether in
the collodion will evaporate rapidly if left uncorked and
the collodion would soon become thick and worthless.
907. When flowing the plate with collodion, exercise
care that you have a clean sweep of the collodion over the
entire plate. Should any portions receive a double coating,
waves and streaks would be caused in the negative. Be-
ginners are liable to permit the collodion to run over the
back of the plate. With a little practice, however, working
carefully and not using too much of the collodion, you will
very soon be able to coat a plate properly.
908. In cold weather you will find that the collodion
will set much slower than in the summer or warm weather.
When there is an even dullness over the entire surface of
the plate, which usually requires but half a minute, you
can be certain that the coating is set and the plate is
ready for the silver sensitizing bath. If you are at all in
doubt, gently touch the corner of the plate, from which the
collodion was drained, with the tip of the finger. If it shows
signs of tackiness it is properly set. This test is usually
unnecessary, as you will soon be able to judge by the ap-
pearance of the collodion on the surface.
909. Placing the Plate in the Silver Bath. — All the
previous operations may have been performed while the
dark-room door was open, using plenty of light. At this
stage, however (placing the plate in the silver bath), it is
advisable to close the dark-room door, for while the plate
is not sensitive to light until after it has entered the silver
bath, yet, unless the location of the silver bath is sufficiently
far from the door, the light might affect the quality of the
plate; therefore, to insure safety close the door while im-
mersing the plate. Place the plate firmly on the tips of
the dipper and gently lower it with one continuous sweep
fVei Plate Process, 313
into the silver bath. If you were to immerse a part of
the plate and then stop for only part of a second before
continuing the immersion, the plate would be liable to bear
a line or mark across it at that place.
910. After the plate is fully immersed, it is advisable
to raise and lower it a few times in the solution. This
enables the solution to penetrate the film more readily,
also removes the ether from the surface, and the action
of the sensitizer becomes even. The plate should remain
in this bath for about six minutes. The exact time, how-
ever, is governed by the temperature and the nature of the
sensitizer employed. Usually, the higher the temperature
the shorter the duration of the plate in the bath ; therefore,
in summer months, or in hot climates, two-thirds of the
time required for winter months or cold climates will be
necessary.
911. The single iodized collodion requires less time
for immersion than where the collodion has been bromo-
iodized, the latter of which is the method recommended
herein. In the latter case it will generally require five to
six minutes, while in the former, three minutes will be
sufficient. The proper immersion can be judged from the
appearance of the plate. If it appears at all wavy or oily
on the surface, the plate has not been sufficiently immersed
and must remain until this appearance takes place. Of
course, the plate must be examined by the yellow light and
not by daylight.
912. Loading the Plate-Holder. — The wet plate, as its
name implies, must be exposed while in its wet condition.
After the plate has been in the silver bath a sufficient
length of time, it is ready to be placed in the holder. Draw
the plate from the bath slowly and carefully, slightly tilt-
ing it to one side, thus permitting the excess silver to drain
back into the bath ; then, catching the plate by two opposite
corners, place it into the plate-holder in the usual way,
when it is ready to be exposed.
913. Exposing the Plate. — Having focused on the
ground-glass the object which you wish to photograph.
314 Library of Practical Photography.
place the plate-holder in position, close the shutter and
draw the slide. In order to test the rapidity of your bath,
proceed in the following manner : Make a test by exposing
two or three plates, ranging in time from ten to forty
seconds. Keep a careful memorandum of each plate and
exposure, and compare the results after developing. Re-
member that plates prepared with silver iodide may require
twelve to twenty times the exposure of an ordinary dry
plate, while those which have been prepared with bromo-
iodide, or with collodion which is bromo-iodized, according
to the formula described herein, will be much faster. One
advantage of the wet plate, like the slow dry plate, is the
great latitude of exposure allowable — you may over-expose
considerably without any serious results.
914. Caution. — For the benefit of those unaccustomed
to handling wet plates, but familiar with the handling of
dry plates, we would advise never allow your fingers or
anything else to come in contact with the coated side of
the plate. The film is extremely tender, and even a strong
flow of water will often destroy it completely.
915. Developing the Plate. — Into a graduate or large-
mouthed bottle, pour sufficient developer to cover the en-
tire plate — usually from three to five ounces being suffi-
cient. Remove the plate from the holder and hold it by one
corner with your left hand over the sink. With the devel-
oper in your right hand, flow the plate with a sweeping
motion, spreading it over the entire plate in one operation.
It is important that the entire plate be covered with one
sweep. To do otherwise would give you streaks, and as
the developing solution is inexpensive a liberal quantity
should be employed. With a little practice you will be able
to flow the plate successfully.
916. After the developer is flowed over the plate,
slightly rock it backward and forward, thus keeping the de-
veloper in motion over the plate for twenty to thirty seconds.
If the image flashes up quickly and is of an even gray color,
you have over-exposed ; but, on the contrary, if it builds up
slowly or in black and white patches, you have under-ex-
Wet Plate Process. 315
posed. This is, of course, supposing that all previous opera-
tions have been properly carried out. The appearance
of the properly exposed plate is similar to an ordinary dry
plate which has been bleached in mercury. When viewed
by transmitted light it is of a brownish color, and of a
creamy color when examined by reflected light. Examine
the plate for density by holding it before the orange light,
and unless you have carried the developing far enough the
plate will not appear sufficiently dense. Rinse the plate
under the tap of running water and again flow with devel-
oper. With a little experience you will soon be able to
judge the proper density to which the plate should be car-
ried in the developing.
917. Fixing the Plate. — When the plate is completely
developed, it is rinsed under the tap and then placed directly
into the fixing bath. It must remain in this bath until all
yellowness entirely disappears from the plate. Where
potassium cyanide is used as the fixing agent, bear in mind,
as previously stated, that this is a deadly poison. Do not
allow it to come in contact with scratches or sores. The
bath containing the cyanide should be kept closed, as the
fumes from the cyanide are sometimes injurious to the
health.
918. Washing the Plate. — After the plate is thor-
oughly fixed it can either be washed under the tap, by
hand, for five or ten minutes, or placed in the regular wash-
ing box fifteen to twenty minutes. After washing, the plate
is set in the negative rack to dry.
919. Re-Developing. — There are times, when using
a newly prepared, or overworked, bath that the image does
not develop up as strongly as you would like, with the
result that the negative is weak. Such negatives can be
improved very materially by re-development.
920. The Re-Developing Solution. — In a small bottle,
prepare a 10% solution of nitrate of silver. Acidify this
solution with a drop or two of nitric acid, C. P., or sufficient
to instantly turn blue litmus paper red. Label this bottle,
" Silver Stock Solution for Re-developing."
316 Libraryf of Practical Photography.
921. Applying the Re-Developer. — When developing
the plate in the ordinary way, and after applying the de-
veloper, you find the plate still lacks strength, pour into
your tumbler or a graduate, 4 or 5 ounces of your developer.
Add to this about 10 drops of your silver re-developing solu-
tion to every ounce of developer and flow the plate with
this combined developer. This re-developer will consider-
ably increase both detail and density, and should only be
used when the image from the first application of devel-
oper appears weak and lacking in detail. If, however, the
negative is weak but has sufficient detail, intensification is
necessary.
928. Intensifying. — Where the plate simply lacks in
density, the image may be intensified by either of the fol-
lowing formulae :
923. The first formula is made up of pyrogallic acid
and the second of ferrous sulphate. We would recommend
the second formula, although very good results can be ob-
tained with either. The pyro intensifier will build up the
image much more readily than the iron. This method,
therefore, is more suitable for a negative which has been
properly exposed, but possibly under-developed. The sec-
ond formula is best applied on negatives which have been
under-exposed, but fully developed.
Formula No. 1.
Pyrogallic Acid 40 grs.
Citric Acid 50 grs.
Water 20 ozs.
Formula No. 2.
Ferrous Sulphate 120 grs.
Citric Acid 240 grs.
Water 20 ozs.
924. Wash the plate thoroughly and flow the inten-
sifying solution over it in the same manner as you flow
the developer over the plate. Constantly rock the plate
until you have produced sufficient density, after which it
should be washed thoroughly.
925. Intensifying may be done before or after fixing.
IVet Plate Process. 317
If the plate is over-exposed it is advisable to intensify after
fixing ; if under-exposed, before fixing.
926. Washing. — After intensifying and fixing, the plate
should be thoroughly washed in the usual manner. It may
then be dried by holding over a gas or oil stove, or may
be placed in a negative rack to dry. If drying is hastened
by artificial means, the density of the negative will be
slightly increased.
927. Varnishing. — The surface of the negative even
when dry, is very easily marred or scratched, as the collo-
dion film is extremely delicate. It is advisable, therefore,
to coat it with some hardening substance in the form of
a varnish. Regular negative varnish may be purchased
ready for use from any photographic supply house, or you
may prepare it yourself by dissolving one pound of seed-
lac in a gallon of pure alcohol. This should be kept in
a warm place, and it may require a number of days for it
to dissolve. The bottle should be shaken occasionally.
When the ingredient is dissolved, decant and filter.
928. Varnishing the Plate. — To varnish the negative
grasp it firmly between the thumb and first and second
fingers, in a similar manner to that described for flowing
the plate with collodion. Hold the plate over a gas or oil
stove until it becomes of a uniform blood-heat throughout;
then apply the varnish in exactly the same manner as you
did when coating the plate with collodion. Drain the su-
perfluous varnish into another bottle. The object of drain-
ing into a separate bottle is, that particles of dust may
collect while varnishing. If this dust were poured back into
the stock bottle of varnish it would soon become charged
with dirt: while if drained back into a separate bottle, after
a sufficient amount of this varnish has accumulated it can
be filtered and then added to the fresh stock, when it will
be free from dust or dirt.
929. After the plate has been flowed with the varnish
hold it over a gentle heat (not too close to it) until the
back becomes uncomfortably hot. Keep the plate rocking
so as to distribute the heat evenly throughout. To hold
318 Library) of Practical Photography.
the plate too near the heat or flame might result in the
varnish catching fire. Should it by accident catch fire,
blowing over the plate will extinguish the blaze. As before
stated, there are many good varnishes on the market, some
of which may be applied to the plate when cold. Others
require the heating of the plate. Usually a method for
applying the varnish accompanies each bottle. Should the
varnish become thick from age, such varnish applied to the
plate may cause the loss of definition and should not be
used. Always dust the plate before varnishing it.
930. When using varnish which requires the nega-
tive to be warm when applied, should the varnish have
an all-over frosted appearance, you will know that the
plate has not been sufficiently heated. Should the var-
nish form ridges over the plate, you have not taken care
to tip the plate in one direction only when varnishing.
Never allow the varnish to run back over the surface
which has previously been covered, but have the flow
all in one direction and keep the varnish constantly
moving. Never allow the body of the varnish to remain
on one spot while flowing the plate. When the varnish
is too thin and the plate too cold, you will produce a
frosted surface. When it is too thick, it is liable to cause
ridges.
931. Keeping the Sensitizing Bath in Working Condi-
tion.— From constant use the silver bath will in time be-
come charged with soluble salts, resulting from the nu-
merous collodionized plates which have been sensitized in
this bath. It is advisable, therefore, to have two baths
in working order, and while one bath is in use the second
may be doctored and put in condition. Unless the bath has
been worked hard, ordinarily pouring it into a large bottle
and placing in the sun for a day or so will precipitate all
the impurities. At the same time a certain amount of the
solution will evaporate, and it will be necessary, therefore,
to bring up the bath to its normal quantity by adding dis-
tilled water to the bath, after which it should be tested
for strength and brought to the normal condition.
IV et Plate Process, 319
932. The sunning of the bath will also evaporate the
excess ether which has accumulated from the collodion,
and all organic matter will, as a rule, be precipitated to the
bottom of the bath. Usually, the bath is again in condition
for use after a good day's sunning. If the bath is very
much overworked, however, it may have become seriously
charged with organic matter. Under such conditions you
will need to resort to the boiling of the bath. To do this
pour the solution into an enamel or earthen dish and place
over a lighted gas or oil stove. Before placing over the
fire, however, first neutralize the bath — make it alkaline —
by adding a few drops of ammonia, and test with red lit-
mus paper. When the red litmus paper turns blue, the
bath is alkaline and may be placed on the fire to boil. The
object of neutralizing the bath is to precipitate all organic
matter.
933. When the bath comes to a good boiling stage,
you will find the color of the bath to be black and turbid.
The heating will cause evaporation and when evaporated,
or boiled down to about one-third its former quantity, re-
move it from the stove and allow to cool, then filter. Before
filtering, however, you should test the bath with the hy-
drometer, when you will find it very strong, the strength
being increased as the bulk of the bath decreases by
evaporation. You will, therefore, need to add sufficient
distilled water to bring it to its original quantity, then
finally test with the hydrometer.
934. As a certain amount of silver is deposited upon
each plate sensitized, the bath when brought back to its
original quantity, naturally will be weaker and it will be
necessary to add more nitrate of silver to bring it up to
its normal strength. All this should be done before the
bath is filtered.
935. Fusing the Bath. — There is still another method
of doctoring a bath, which is termed fusing. This method
is similar to the one just described, only that you carry the
work farther. You continue the evaporation to dryness,
allowing the bath to remain on the stove until all the frothi-
320 Library of Practical Photograph}).
ness has disappeared. This process, however, is best done
in an earthen dish, which can be purchased from any pho-
tographic supply house.
936. When the bath is brought to the proper stage and
the frothiness has disappeared, remove it from the stove
and gather the mass into a lump in the center of the dish ;
then apply to this a diluted solution of nitric acid prepared
in the proportion of about 1 ounce nitric acid to 12 ounces
of water, which will redissolve the silver. By placing the
dish over the fire again the bath is once more evaporated
to dryness, after which the sediment is dissolved in dis-
tilled water. Additional distilled water is then added until
the bath is brought to its normal quantity and sufficient
additional nitrate of silver crystals added to bring it to the
proper strength. By this latter method all organic matter
will have been thoroughly carbonized, and after acidifying
the bath with a few drops of nitric acid and testing with blue
litmus paper it is again in good condition for use.
937. Special Formula. Negative Collodion. Good for
Ferrotypes also. —
Alcohol 5 ozs.
Ether 10 ozs.
Negative Cotton 100 grs.
Alcohol 5 ozs.
Iodide of Ammonium 60 grs.
Iodide of Cadmium 30 grs.
Bromide of Cadmium 20 grs.
Dissolve in the order given.
938. Note. — The salts used for collodion should keep
and react neutral. Cadmium salts thicken the collodion ;
alkaline salts make it thinner. Three to four parts of iodine
compound are generally taken to one or one and a half
parts of bromine salts; 166 parts of iodide of potassium
are equal to 186 parts of iodide of sodium, or 145 parts
of iodide of ammonium, or 134 parts of iodide of lithium ;
119 parts of bromide of potassium are equal to 139 parts
of bromide of sodium, or 98 parts of bromide of am-
monium, or 172 parts of bromide of cadmium. Calcium
Wet Plate Process. 321
salts work the slowest; cadmium the quickest, and are
also the coarsest. Iodide of potassium soon discolors the
collodion containing it, and does not keep well. Bromine
and iodine make the collodion gelatinous. Excess of bro-
mine gives a blue film, and iodine a gray film.
939- Special Developer for Negatives. —
Protosulphate of Iron (saturated solution) 2 ozs.
Acetic Acid 1 oz.
Water 20 ozs.
940. Negative Varnish. —
Alcohol 60 ozs.
Sandarac 10 ozs.
Camphor 1 oz.
Castor Oil 2 ozs.
Venetian Turpentine 1 oz.
941. A Simple Negative Varnish. —
Sandarac 2 ozs.
Venetian Turpentine % oz.
Oil of Turpentine 1 oz.
Alcohol (825) 20 ozs.
This varnish is of a pale color and gives a very hard film.
The plate must be warmed previous to coating.
CHAPTER XXIII.
Difficulties — Wet Plate Process.
942. Parts of the Film Leave the Plate. — This is a certain
sign that the collodion has not been sufficiently set before sensi-
tizing, or if the collodion has been well set before sensitizing and
the film still leaves the plate, try albumenizing the plate before
flowing with the collodion. Be sure this albumen is thoroughly
dry before you apply the collodion.
943. Parts of the Film of the Plate Thicker than Others. —
This is a certain sign that the plate was not evenly flowed with
collodion. Some portions may have been double-coated by tip-
ping the plate so as to allow the collodion to flow back over the
portions which were formerly coated.
944. Parts of the Plate Apparently not in Contact. — This
would indicate that the plate was not thoroughly cleansed. Par-
ticles of old film may have been allowed to remain upon the
plate. Where mercury was used for intensifying the old plate which
you have washed and again used, unless the mercury is entirely
eliminated in the washing this same trouble would appear. Nitric
acid is the only chemical that will entirely eliminate these defects.
To be absolutely certain of overcoming such defects the plate may
be albumenized before collodionizing it, according to instructions
given in the lesson. Dampness of the plate will give the effect
of lack of contrast. Always examine the plate carefully before
collodionizing and see that it is perfectly dry.
945. Ridges in the Emulsion. — This is generally caused from
a collodion that is prepared too thick, but it may also be caused
from a piece of bad glass with chipped edges, which will many
times cause the collodion to clog and not sweep cleanly over the
plate, resulting in furrows in the emulsion. The only remedy for
the latter is not to use such plates. See that all glass has clear
edges and is free from defects generally.
946. Part of the Plate Thinner Coated than Others. — This may
be caused from using too thin a collodion; the upper portion of the
plate being flowed first would then not receive as heavy a coating
as the lower portion. It may also be due to an excess amount of
alcohol, causing the plate to dry too rapidly, and as it would
323
324 Library of Practical Photography.
naturally dry more rapidly at the top than at the bottom, it would
give an uneven coating.
947. Fine Net Work Markings Over the Film. — This may
be caused from too much bromide of cadmium or lack of sufficient
alkali. Perhaps more ammonium iodide would rectify the defect.
948. Weak Image in the Negative. — This is probably due to
lack of sufficient gun-cotton; the use of old gun-cotton will also
produce this result.
949. Straight Lines Across Plate After Sensitizing. — This is
evidently due to improper immersion in the silver bath. The plate
was not lowered in the bath with one sweep, but, on the contrary,
you halted for a second, when only a portion of the plate was
immersed.
950. Straight Perpendicular Lines. — This may be' caused by
the bath becoming charged with alcohol liberated from the collo-
dionized plates. Such a bath should be boiled down for an hour,
when most of the alcohol will be driven oflf in vapor. After the
bath becomes cool it may again be brought up to its normal bulk by
the addition of more pure water, and after filtering it is again
ready for use.
951. Scum on the Film. — This is usually caused by too strong
a silver bath. Test the bath with the hydrometer. If it registers
over 45° reduce with pure water. Sometimes the collodion may
be too strongly bromo-iodized. In such a case, add a little plain
collodion to the iodized collodion, which will overcome the
difficulty.
952. The scum may also be formed on the wet negative, from
a scum that sometimes collects on the surface of the sensitizing
bath. In such a case, float a strip of tissue-paper over the bath.
The scum will collect on the tissue and can be withdrawn. It may
require two or three such applications to remove it entirely. By
careful use of the bath, keeping the dark-room clean and free from
dust, and the sensitizing bath dish always covered, you will seldom
experience any trouble. When the trouble does appear it is almost
certain that the bath has become contaminated, and the best
thing to do is to give it a good sun bath, by pouring it into a
bottle and placing it in the strong sunlight for a day or two.
Before sunning, however, the bath should be made alkaline with
carbonate of soda or a few drops of ammonia. A small quantity
only will be required, and if not certain that it is alkaline test with
red litmus paper. When this paper turns blue the bath is alkaline.
953. Pin-Holes. — These may be caused by dust on the plate
while collodionizing it. They may also be caused by too much iodide
in the collodion, and, sometimes, even an insufficient amount of
iodide will produce pin-holes. If you are careful to prepare the
Difficulties— Wet Plate Process. 325
collodion according to formula, and procure C. P. fresh chemicals,
you will not experience any trouble.
954. Comet-Like Spots. — These are sometimes caused by un-
dissolved particles of gun-cotton in the collodion. They are also
caused by rust from the water faucet. Always filter your fresh-
made collodion, and it is also advisable to filter the water from the
tap. A linen cloth placed over the mouth of the faucet will answer.
955. Round Black Spots. — These are usually caused by dust
in the air. Remedy: Keep the dark-room closet free from dust
of any kind.
956. Contrasty Negatives. — This may be due to too acid a
silver bath. Either the bath when freshly made may have been
too strongly acidified, or, if it works well when fresh, it may have
become charged with acid by constant use. The iodide in the
collodion will in time liberate the nitric acid in the film thus charg-
ing the bath with considerable of the acid, which may cause trouble.
By occasionally testing the bath with litmus paper it may be
kept at the right stage. If at any time it tests strongly acid, it
may be slightly neutralized by the adding of a little carbonate
of soda. It is advisable, after adding the soda, however, to sun
the bath for a few hours, and again filter before using.
957. Circular Marks on the Plate. — This is usually caused
from drops of silver on the back of the glass plate. To overcome
this, either wipe off the back before placing in the holder, or it
will be good practice to back up the plate with another plate
stained a dark color. This will usually overcome such difficulty.
958. Streaks in the Developed Plate. — These may be caused by
uneven flowing of the developer, or not flowing the plate with
one sweep. If the plate is allowed to stand in the holder for some
time before use, this will cause the upper portion to slightly dry
out, and, therefore, the dry part will not develop as freely as the
wet portion. Streaks may also be caused if, by accident, water
was first poured over the plate in place of developer, and afterward
the plate was flowed with the developer. The water coming in
contact with the plate first will give the surface an oily appearance,
which the developer cannot overcome; therefore, care must be
exercised when working near the tap, that even a drop of water
does not fall upon the plate before the developer has been applied.
959. Fogged Plates. — This you will find may come from any
of the following causes: By over-exposure; by light entering the
camera; by lack of suflicient acetic acid in the developer; or by
the silver bath becoming alkaline. When such trouble presents
itself it is advisable to first test your exposure. Prepare another
plate and give less exposure than given the former. If the plate
still appears fogged, examine the camera and plate-holder. See
326 Library of Practical Photography.
that there is no trace of light entering. Should even slight cracks
in the bellows, or a small hole in the plate-holder appear, these
are sufficient to fog the plate, and you should at once repair them.
Should the camera prove safe and light-tight, then test your silver
bath with both red and blue litmus paper. Should the bath test
neutral — if neither litmus papers turn from their original color —
then you will know that the bath is at fault, as it should be worked
acid. This may be accomplished by adding a few drops at a time
of nitric acid C. P., stirring with a glass rod and testing with blue
litmus paper. When the bath turns blue litmus paper red it is in
proper shape and this difficulty will be overcome. If the bath is
not at fault, then look to your developer. You may have omitted
the acetic acid, or you may have added an insufficient amount.
To test this, expose another plate and pour the regular portion
of developer in a tumbler or graduate, adding to it a few drops of
acetic acid; then develop the plate with this developer, when you
will very likely find all traces of fog disappearing. Exercise care
that there are no vapors, fumes from ammonia, or gas in the room,
as these will affect the manipulation of the plates.
CHAPTER XXIV.
Wet Plate Photography for the Photo-Engraver.
By Charles A. Stinson, Supt.,
Gatchel & Manning, Illustrators and Engravers, Philadelphia, Pa.
960. The " wet plate process " is the method used by
the photo-engraver in making the negatives for half-tone
and line engravings. It is not only the first part of the
process, but is also one of its most important stages, and
requires considerable judgment and skill to produce the
" proper kind " of a negative.
961. While there are several different formulae in use,
it is only necessary for the student to acquire the knowl-
edge of one of each of the different stages (the ones given
in this article are amongst the easiest to use).
962. In the first place, the operator should learn to
be very " clean " in all his work, and also be economical
in the use of his chemicals (considerable money can be
wasted in the misuse of chemicals), as not only must the
negative be of good quality, but it must be produced at a
minimum cost.
963. The formulae for each of the parts and the order
in which they are to be used are as follows :
964. Preparation of the Glass. — The glass — which
should be carefully selected, and be perfectly flat and free
from imperfections — is first immersed in a solution of nitric
acid (commercial) for at least twelve hours, then taken
out and thoroughly washed with a brush, under running
water, next rinsed and flowed twice with a solution of al-
bumen, and afterward placed in a rack to dry.
965. Albumen Solution. — The solution of albumen is
327
328 Library^ of Practical Photography.
made from the white of one egg, 33 ounces of water, to
which is added 10 drops of aqua ammonia. Flow as many-
plates as you desire with the albumen and place in the rack
to dry, when they are ready for collodionizing.
966. Collodionizing the Plate. — After being thor-
oughly dried, the glass is now ready to be coated with the
collodion solution, which is made diflferently for produc-
ing either half-tone or line work as follows:
967. Collodion Solution for Half -Tone Work. —
Alcohol 32 ozs.
Ether , 32 ozs.
Cotton (Negative) 360 grs.
Iodide of Cadmium 150 grs.
Iodide of Ammonium 90 grs.
Chloride of Calcium 30 grs.
Chloride of Strontium 30 grs.
968. Collodion Solution for Line Work. —
Alcohol 32 ozs.
Ether 32 ozs.
Cadmium Bromide 120 grs.
Iodide of Ammonium 320 grs.
Negative-Cotton 1 oz.
969. The glass is now ready for the silver bath, which
is made up as follows:
970. Silver Bath. —
Silver Nitrate 8 ozs.
Water (Distilled) 120 ozs.
Iodide of Potassium 10 grs.
Nitric Acid (C. P.) about 15 drops, or enough to turn litmus
paper slowly red. Then the bath should be carefully filtered. This
should test 42° with the hydrometer.
971. Before making an exposure of a plate, other
necessary solutions should be made up ready for use, as
follows :
972. Developer. —
1 oz. Protosulphate of Iron dissolved in 20 ozs. of water.
Acetic Acid 4 ozs.
This should test 20° with the hydrometer.
Wet Plate Photography for Photo-Engraver. 329
973. Fixing Solution. —
Potassium Cyanide 1 oz.
Water 18 ozs.
974. No. 1 Intensifier. —
4 ozs. Sulphate of Copper in 20 ozs. of water.
2 ozs. Bromide of Potassium in 20 ozs. of water.
Then mix together.
975. To "blacken" negatives made with this inten-
sifier, use a solution of Y^ ounce of silver mixed with 6
ounces of water.
976. No. 2 Intensifier. —
Bichloride of Mercury 1% ozs.
Water 20 ozs.
Ammonium Chloride 1 oz.
977. To "blacken" negatives made with this inten-
sifier, use a solution of Y2 pound sulphate of soda mixed
with 32 ounces of water.
978. Reducer. —
Potassium Cyanide 60 grs.
Water 6 ozs.
Iodine Solution (made as follows) 10 drops.
979. Iodine Solution. —
Iodide of Potassium 1*4 ozs.
Iodine (Resublimed) % qz.
Water ; 16 ozs.
980. With the different solutions all prepared ready
for use, the next stage in the operation is to coat the plate
with the collodion solution, then immerse it in the silver
bath, slowly lowering, without stopping for an instant, un-
til it touches the bottom (otherwise it is apt to show
streaky). The plate should then be left in the silver bath
for three or four minutes. While this is being done the
operator usually is tacking up his copy and adjusting the
focus on his camera. To get the picture sharp on the
ground-glass use the lens wide open; then, placing the cap
330 Library of Practical Photograph}).
on the lens and inserting a small diaphragm, and after re-
moving the ground-glass, the camera will be ready so the
plate-holder may be placed in position.
981. Exposure. — The amount of time necessary for the
exposure must be judged by the amount of reduction, quality
of lens and the intensity of light, and this portion of the work
can only be learned by practical experience. A safe rule
to follow is to expose about ten or fifteen times as long as
you would a dry plate under the same conditions. It
should be remembered, however, that exposures through
the screen for half-tone work will require about four times
that of a negative intended for line work.
982. With the exposure determined, and the plate
being sufficiently immersed, the operator now returns to
the dark-room, lifts his plate from the bath and drains it;
then, leaning it against a support, which should be covered
with a piece of clean blotting paper, he wipes off the back of
the plate with a piece of soft tissue paper. Before placing
the plate in the holder, a strip of blotting paper is laid on the
trough or bar on which the plate will rest ; this will take up
silver waste during exposure and prevent rotting of the
holder. (If the required exposure is for producing a half-
tone plate, care should be taken to see that the half-tone
screen has been placed in proper position.)
983. Making the Exposure. — The plate-holder is then
placed in position on the camera, the slide is withdrawn and
the cap removed from the lens for an exposure to obtain
the shadows of the copy; then the cap is again placed on
the lens and the diaphragm is changed for an exposure to
obtain the middle tones, and after the cap is again re-
placed, a third change is made in the diaphragm and an
exposure made for the high-lights. (In making an exposure
for coarse screen work, only two diaphragms are used, one
for the high-lights and the other for the shadows, as a con-
trasty negative is desirable.) If the exposure is for line
work only one diaphragm is used, the size of same depending
upon the color of the copy and the amount of reduction.
984. The best results are obtained by changing the
Wet Plate Photography^ for Photo-Engraver. 331
size of stops during the exposure, proportioning the time
with each, to give good detail throughout, by making a
part of the exposure with the small stop, a part with the
next larger stop, and completing with a short exposure with
the largest stop. In making negatives for half-tone plates,
usually each operator is apt to work differently from an-
other— for instance, some expose first for high-lights, then
the middle tones, then the shadows, while others invert the
order and expose for the shadows first.
985. Further, in making negatives for half-tones, an
important factor is the regulation of the distance between
the screen and the negative in the plate-holder — the finer
the screen used, the closer it is placed to the plate.
986. Developing. — After having made an exposure
and replaced the slide in the holder, the latter is removed
to the dark-room, which is supplied with a ruby light; then
the negative is developed, using the formula already given.
In this operation it is necessary to keep the plate moving
so the developer will be in motion (the more of the solu-
tion that is kept on the plate the denser it will make the
negative). When the whole picture is "up," stop the de-
velopment by washing with a good flow of water under
the faucet, and then use the fixing solution and again wash
thoroughly, which must be done promptly after each
operation.
987. Intensifying. — The negative is then intensified
by the use of the solution, which has to be determined by
the quality of the negative, and after this operation the
negative must be " blackened."
988. If, perchance, the negative is found to be too
strong both in the high-lights and the shadows, it may be
improved by the use of the reducing formula.
989. Local Treatment. — The manipulation of the nega-
tive in all of these particulars, and also treatment locally —
working up small parts to bring necessary gradations of
tone — depends entirely upon the skill of the operator.
990. If the negative has been made with the use of
a prism, it is necessary that it be dried in an oven and then
332 Library of Practical Photography^.
coated with a gum arabic solution, made by mixing 2
ounces of gum arabic and 12 ounces of water, or any of the
negative varnishes that are on the market. (Note : While
practically all engravers use the prism and thereby save
the reversing of the films, yet where the prism is not em-
ployed and a straight negative has been made, it is neces-
sary to strip it to get it reversed.)
991. After the negative is dry and cool, coat with
Rubber Solution.
Rubber Cement 3 ozs.
Benzine 20 ozs.
992. Then let dry and coat with
Plain Collodion.
Ether 8 ozs.
Negative Cotton 120 grs.
Alcohol 8 ozs.
Castor Oil % oz.
993. Then dry with heat. The castor oil is added to
make the film adhere to the glass after being turned. When
cool, cut negative to size and shape wanted, then immerse in
Solution of Acetic Acid.
1 part Acetic Acid.
8 parts Water.
After laying in acid for about live minutes, negative is
ready to strip.
994. In mixing up all formulae, of course smaller quan-
tities of solution can readily be made by following out the
same proportions as stated.
CHAPTER XXV.
Ferrotype Process.
995. Ferrotype Process (Tintype). — While the making
of ferrotypes, commonly called tintypes, is almost a thing
of the past, the process is still employed at summer resorts,
fairs, and even in many cities. A capable and careful worker
may produce results which, while they are not to be com-
pared with the modern processes of photography, are at
least superior to the results obtained generally with the
process in the hands of an unskilled or careless worker.
Lighting, posing and composition can always make them-
selves felt. The photographer who is painstaking in all
departments, in the proper preparing of his collodion silver
bath, his developer, and even the cleaning of his ferrotype
plates, will produce results that will have commercial value
and that will be sought after.
996. The tintype is simply a collodion positive upon
a dark enameled plate, called a ferrotype plate. The image
appears reversed as regards left and right. The process is
practically the same as that employed in the making of
collodion wet plates, save that metal plates are used in place
of glass, and that it is a positive and not a negative. White
will appear white on the plate, and black will be black. The
coating of the plate, the developing, fixing, intensifying,
washing, drying and varnishing are practically the same as
with a wet plate negative.
997. Apparatus and Material — The Camera. — The ap-
paratus for tintype work usually consists of a 5x7 camera,
a small three-legged camera stand, and a set of Gem lenses,
either four quarter-size tubes or eight one-eighth-size tubes,
the former being the most universally used.
998. The camera is fitted with divisions, separating
the four pictures on the plate. A special wet-plate holder
333
334 Library of Practical Photography.
is also provided. With this same camera cabinet size pic-
tures can be made, also postal photographs. When used
for either of the latter purposes the division is taken out
and the Gem lenses are replaced with a portrait lens.
999. For regular studio work, where an outfit for por-
traits and groups, also tintypes, is desired, then an 8 x 10
portrait camera may be employed with a Gem attachment
for making tintypes. Catalogs illustrating these outfits
can be secured from any large dealer in photo supplies.
1000. The regular tintype camera has a distinct ad-
vantage over the ordinary portrait camera, inasmuch as it
is more compact. The plate-holder is supplied with silver
wires for the plates to rest upon, and a gutter or glass trough
at the bottom to catch the drippings from the plate. If
the ordinary plate-holder is used, apply paraffine to the part
on which the plate is placed. Blotting paper may also be
placed both on the back of the plate and on the bottom of
the plate-holder.
1 00 1. Camera Stands. — A good, solid stand should be
employed, as the exposures necessary will be of considerable
length and there should be no danger of the camera jarring.
1002. Dark-Room. — Any ordinary dark-room will do.
(See description of dark-room in Paragraph 870, instructions
on Wet Plate Process.)
1003. Other Materials. — Bottles for your collodion,
same or similar to those used for wet plate process ; bot-
tles for developer, and silver bath ; glass baths for holding
the silver, and one for fixing bath ; two dippers — one for
silver and one for fixing bath. You should also have one
or two glass funnels for filtering.
1004. Ferrotype plates may be purchased by the box
or by the dozen. For the beginner a few dozen plates will
be sufficient. Purchase the 10 x 14 size and with a shears
cut them into four parts ; this will give you four 5x7 plates.
On each 5x7 plate you can make four of the ordinary size
tintypes. At summer resorts these pictures are often sold
as high as four for one dollar. Ordinarily, however, 50 cents
is the price for four pictures.
Ferrotype Process. 335
1005. Making the Collodion. — Collodion can be pur-
chased ready for use. The Anthony Positive Collodion,
which can be purchased from any photographic dealer, will
be found exceptionally good and economical. However,
for the benefit of those who desire to make their own collo-
dion we give the following formula :
1006.
Ether 20 fl. ozs.
Alcohol 20 fl. ozs.
Gun-Cotton 200 grs.
Bromide of Cadmium 100 grs.
Iodide of Cadmium 80 grs.
Iodide of Ammonium 120 grs.
Place your gun-cotton in a large-mouthed bottle or graduate;
add to this the alcohol and then the ether. When the gun-cotton
is entirely dissolved, filter.
1007. Bromo-Iodize. — The ether, alcohol and gun-
cotton mixture comprises the plain collodion. It must now
be bromo-iodized. This is done by simply pouring into
a clean graduate a few ounces of the plain collodion and
then adding the bromide of cadmium, the iodide of cadmium
and the iodide of ammonium. Stir with a glass rod until
all ingredients are dissolved, and then add them to the
balance of plain collodion,
1008. Plain Collodion. — The following formula is also
an exceptionally good one :
Ether, specific gravity 725 10 fl. ozs.
Alcohol, specific gravity 805 5 fl. ozs.
Gun-Cotton 120 grs.
Pour your alcohol on the gun-cotton, then your ether, after
which filter. This is your Plain Collodion.
1009. Bromo-Iodizer. — In order to bromo-iodize the
plain collodion, dissolve in five fluid ounces of alcohol, the
following :
Iodide of Cadmium 50 grs.
Bromide of Ammonium 25 grs.
When the iodide and bromide are fully dissolved add to the
plain collodion.
336 Library of Practical Photograph}).
loio. Preparing Silver Baths. — Place 16 ounces of dis-
tilled or pure water in your graduate. In this dissolve one
grain of potassium iodide, then add one ounce of nitrate of
silver. Dissolve the silver and thoroughly mix the solution,
allowing it to stand in the sunlight for four or five hours.
You will probably find that there will be a slight precipita-
tion. Decant into your silver bath all of the solution that
you can without disturbing this precipitation. Next add one
or two drops of nitric acid — sufficient to make the bath turn
blue litmus paper faintly red. If the silver bath is too
acid, marks on the film will appear; if too little acid is
used the image will appear flat and of a dirty gray appear-
ance. If the bath is too acid add a little neutral silver solu-
tion. Dissolve a little of the neutral silver and add it di-
rectly to the bath. To overcome the flat, dirty gray ap-
pearance, simply add a drop or two more of nitric acid.
loii. Another very good formula is as follows:
Nitrate of Silver, re-crystallized 5% ozs.
Distilled water 80 fl. ozs.
Nitric Acid C. P % drm.
1012. This bath should be saturated with iodide of sil-
ver and filtered before using. To iodize your bath see
Paragraphs 892,893, Wet Plate Process.
1013. Formula for Developer. —
Water 16 ozs.
Acetic Acid 1 oz.
Protosulphate of Iron 1 oz.
Alcohol 1 oz.
1 014. As the ingredients used for developer are inex-
pensive, a large quantity should be prepared in advance.
The following amounts will fill a good-sized bottle:
1015. Preparing the Developer. — Place 96 ounces of
water in a large, clean bottle ; then, add 6 ounces of acetic
acid (glacial), 6 ounces of protosulphate of iron, and thor-
oughly dissolve ; next, add 6 ounces of alcohol. The alcohol
will cause the developer to flow easily.
Ferrot})pe Process. 337
1016. Another very good formula for developer is as
follows :
Ferrous-sulphate 150 grs.
Acetic Acid (glacial) % oz.
Nitric Acid 5 minims.
Alcohol % oz.
Water 10 ozs.
Note. — By increasing the proportion of nitric acid and decreas-
ing that of acetic acid the image will be more metallic in appearance.
loi 7. Collodionizing the Plate. — On the supposition that
you have made all preparations and are ready to make your
exposure, you may now proceed to coat or collodionize the
plate. Take one of the ferrotype plates and place on the
tips of the thumb and fingers of your left hand, sufficiently
spreading the fingers to balance the plate. (See instruc-
tion, Wet Plate Process.) With your right hand take your
collodion bottle and pour some of the collodion in the center
of the plate (about half the size of the plate), then, very
slowly and carefully, slightly tilt the plate in the direction
cf the upper right-hand corner. Just before the collodion
reaches the edge, tilt so that it will run very gently and
smoothly toward the upper left-hand corner, then down
along the edge toward the lower left-hand corner, and then
over to the lower right-hand corner. Pour the excess of
collodion into another bottle and allow the plate to drain.
Rock gently from edge to edge — not back to front. This
will cause the collodion to set evenly and prevent streaks.
Just as soon as the plate begins to give a dull surface, the
film will have been properly set. Touch the bottom corner,
and if no longer tacky or sticky it is ready for immersing
in the silver bath. In cold weather collodion will set much
slower than in hot weather. It usually requires but a few
seconds for the collodion to set.
ioi8. Sensitizing. — The collodion on the ferrotype plate,
having been properly set, is now ready for sensitizing.
Place the plate on your dipper and slide it with a gentle,
continuous motion down into the silver bath. If there is
the slighest pause or hesitation it will cause a line across
338 Librar}) of Practical Photography^.
the plate. It is a good plan to raise and lower the plate
a few times after it is immersed. If necessary, carefully
wipe out your plate-holder while the plate is sensitizing.
In fact, it is a good plan to do so often, as dust is sure to
cause all kinds of trouble. The sensitizing of the plate
should be done with the door of the dark-room closed, using
only the regular dark-room light. You may use consider-
able of this dark-room light, but it must be yellow or orange.
Where the glass bath is enclosed in a box and has a cover,
the plate may be dipped into the bath with the dark-room
door open, but the cover must be immediately replaced.
1019. After the plate has been in the bath for about a
minute or two, raise it from the bath and examine it before
the orange light to see that all greasiness has disappeared.
In cold weather it will take twice as long to sensitize the
plate as it will in warm weather. If you find the waves or
oily marks have not disappeared, lower the plate again,
but very gently. When the plate appears quite even, dip
it a few more times, very slowly. When your plate is
properly sensitized, lift it to the top of the bath dish and
allow it to drain for a moment. Next, place your plate into
the holder. Set it in very gently, and place back of it a
piece of glass the exact size of the plate. For example, if
you are using 5x7 plates, use a 5 x 7 glass. You are then
ready to make your exposure.
1020. Exposing. — Place your plate-holder in position at
the back of the camera, being careful, however, that it is
not unnecessarily jarred. Close the shutter and carefully
draw the slide, in order to avoid dust. (For exposure, see
Paragraph 913, Wet Plate Process.) After the exposure has
been made, return the slide to the plate-holder in the same
manner as you removed it. The length of exposure is
governed by the speed of your collodion, strength of light
and rapidity of lens used. Usually, from five to ten seconds
will be necessary.
1021. Developing. — After making the exposure return
to your dark-room and proceed to develop the plate. De-
veloping must be done at once, as the plate must be exposed
Ferrotype Process. 339
and developed while it is wet. Close your dark-room door
and hold the plate with the glass backing over the sink.
The glass backing will hold the tin plate from buckling
during development, and the latter is, therefore, much easier
handled. Grasp it firmly at the left-hand corner with the
thumb and first two fingers of your left hand. Pour the
developing solution over the entire plate with a single
sweep and gently rock the plate so as to keep the developer
flowing to and fro and over the entire surface. This re-
quires a little practice. Never pour on with a splash.
1022. In the sink underneath the plate you should have
a bottle with a funnel. In this funnel place a little absorb-
ent cotton. When the developer flows oflf the plate, it
will flow into the funnel. The cotton will filter it and
this developer may then be used when developing over-
exposures. You should strive to produce as near the cor-
rect exposure as possible. This you can only learn by
experience and carefully watching your experiments. The
exposure cannot be corrected by development, as is the
case when developing dry plates. Should you know in
advance that the plate is over-exposed, then by applying
the once-used developer you will materially improve the
results.
1023. Development of Ferrot3rpe Plate. — The image
will begin to appear almost immediately upon flowing the
developer on the plate. When the shadows appear quite
clear the plate is fully developed and should be immediately
rinsed with water. If the development is stopped too soon
the picture will appear too black ; if it is allowed to develop
too long, the image will appear weak, flat and foggy. When
rinsing, do not allow the water to run too strongly on the
plate, as it is apt to damage the film. If the ferrotype has
been over-developed and, therefore, appears weak and flat,
you can improve it by adding a drop or two of iodine to the
fixing bath. In order that your entire fixing bath does
not become charged with iodine, pour a little of the regular
fixing bath into the tumbler or graduate and add the iodine
to this. Pour a sufficient quantity of this fixing bath over
340 Library of Practical Photograph}).
the ferrotype plate, in exactly the same manner as you did
the developer, draining the surplus solution back into the
tumbler to save for future use. With the image on the
plate brought to its proper stage, rinse under the tap and
place into the regular fixing bath.
1024. Fixing. — After the image is fixed it must be care-
fully washed. While this can be done in a very few minutes
you must be careful that it is done thoroughly. If the
cyanide is not washed out of the film the finished picture
will in a very short time turn yellow and entirely disappear.
Therefore, be careful that the plate receives a thorough
washing. '^tQ formula for fixing bath. Par. 8g8.
1025. Drying. — When the plate is washed it may be
placed in a negative rack and allowed to dry. As a general
rule, however, the picture is to be finished as quickly as
possible ; therefore, the plate should be dried over a gas
or oil stove, or a lamp. You may heat this plate as hot as
your hands will bear. While drying, continually move
the plate over the heat so that the plate will be heated and
dried evenly. When the plate is thoroughly dry it is ready
for varnishing.
1026. Varnishing. — When dry, the image on the ferro-
type plate is extremely soft and tender, and if your fingers
or anything else were to come in contact witlf it, it would
scratch or mar it. It is necessary, therefore, that it re-
ceive a hard coating, which will protect it, and for this
purpose a transparent varnish is generally employed. You
can purchase this already made, or, if you desire, you can
prepare it yourself according to the following formula :
1027. Gasoline Varnish for Tintypes. — Place one gallon
of gasoline in an ordinary oil can, and add one pound of
powdered resin. Then place the can containing the gaso-
line and resin into a kettle of boiling water. To create a
vent, loosen or remove the top of the can. Unless this
is done there is danger of explosion. When the water be-
comes cool discard it and add more boiling water. Con-
tinue this until the resin is entirely dissolved.
1028. Caution. — Under no condition prepare this var-
Ferrotype Process. 341
nish near a stove or where there is fire, gas or lamp light,
as the fumes of gasoline are extremely explosive. If the
varnish is not heavy enough, or does not supply enough
gloss, add more resin.
1029. Drying — After Varnishing. — Flow this varnish
over your tin plate in the same manner that you would any
other varnish. Then hold over a flame, allowing the var-
nish on the plate to catch fire. After it has burned for
a second, blow it out and then dry over a gentle heat. The
varnish, when dry, supplies an extremely hard surface with
an exceptionally brilliant gloss.
1030. When other than the gasoline varnish is used,
the varnish should be flowed over the plate in exactly the
same manner as you did the collodion ; and, then held over
the heat to dry until the varnish is hard and perfectly set.
If you have used four lens tubes and, therefore, made four
exposures on the plate, they must then be cut apart to fit
your ferrotype or tintype holder. Cut the proper size and
trim off the corners. By trimming off the corners you
can slide them into the folders more readily. They are
then ready for delivery.
CHAPTER XXVI.
HOW THE STUDIES ILLUSTRATING THIS
VOLUME WERE MADE.
Study No. 2, title, "Woodland Mist," by W. T. Knox,
New York, N. Y. The weather conditions, dull and misty;
exposure was made in the morning ; lens used, single combi-
nation of Zeiss; focal length, 23 inches; stop used. No. 4; ex-
posure given, 4 seconds ; plate used, Cramer Instantaneous
Isochromatic ; developer, pyro. Diffusion was obtained in
focusing on the foreground. Printing process, platinum ;
mounted on a dark grey mount.
Study No. 3, title, "Morning Lights and Shadows," by
J. H. Field, Berlin, Wis. Weather conditions, sun shin-
ing through the mist ; time of day exposure was made, about
6 A. M. ; lens used, Rapid Rectilinear, using rear half of lens
only; focal length, 15 inches; stop used, wide open; exposure
given, I second ; plate used, Cramer Medium Isochromatic ;
developer, pyro-acetone. The diffused focus in this picture
was obtained by printing through celluloid and thin paper.
The negative was slightly reduced in the sky portions after
development. Printing process, Willis & Clements Platinum,
black and white. This print was made from an enlarged
negative, the original size of which was 5x7; mount was on
oil tissue paper over cream.
Study No. 4, title, "At Peace (Warship)," by Dr. A.
R. Benedict, Montclair, N. J. The weather was cloudy,
with a clear atmosphere ; exposure was made at 4 130 P. M. ;
94S
344 Library of Practical Photography.
lens used, Rapid Rectilinear; focal length, 6^ inches; stop
used, U. S. 4; exposure given, -^j second. Negative was
made on an Eastman film ; developed with metol-hydro-
quinone, with no after manipulation of the negative ; printing
process, the direct print from the negative on velox, rede-
veloped with Eastman sepia redeveloper. Note : This
picture was made from two negatives; that is, the clouds were
printed in. Both negatives, however, were taken on the same
day, the clouds in one negative and the scene in the other, and
then printed in. This scene is on the Hudson river.
Study No. 5, title, *' Sheep," by W. E. Bertling, Buffalo,
N. Y. Mr. Bertling states: "I use in all my work a Goerz
lens, focal length 7 inches, and generally use diaphragms full
opening, Forbes dry plates and develop with Pyrocatechin.
I obtain my diffused focus by using full opening of lens and
focusing upon middle distance. Printing process, usually
developing paper of various kinds. In making my picture I
always endeavor to get an element of sky effect in my land-
scapes, and always give plenty of time in exposure up to a
reasonable limit. I always start development with weak de-
veloper and strengthen afterwards to suit requirements. For
personal use and exhibition purposes generally I use the car-
bon process or glycerine platinum process. I generally try
to work out the salvation of my subject in the printing pro-
cess. The various kinds of pigment processes offer a wide
field for manipulation, and this advantage possesses an at-
traction for me."
Study No. 7, title, "Snow Lights," by Geo. H. Scheer,
M. D., Sheboygan, Wis. Hung at the Fourth American Sa-
lon. This picture was made on a very bright sunny day, at about
3 P. M., in the month of March. Lens used, Rapid Rectili-
near, wide open; plate used, Orthonon; exposure given, one
second, with Burke & James Ideal Ray Filter ; developed in
dilute pyro-soda developer. Print was made by straight en-
largement from an unaltered negative; enlargement was made
on Platinoid Bromide, 10x12 inches, from only a portion of a
5x7 negative.
Study No. 8, title, "A Dull October Day," by John Chis-
Horo the Studies Were Made. 345
lett, Indianapolis, Ind. Exposure was made at 4:30 P.M.,
with a Smith lens, very slightly stopped down ; plate used,
Cramer Instantaneous Isochromatic ; exposure given, 3 seconds;
plate was developed in ortol; there was no altering of the
negative or manipulation after development ; print was made on
Platinum paper, with the foreground darkened in the print-
ing, and a sky printed in from a separate negative. The
print was mounted on a light Scotch grey mount.
Study No. 9, title, "Wave Action," by J. R. Peterson,
Portland, Ore. Picture was accepted and hung at Third
American Salon. This picture was taken after a clearing
storm, with a dull light; exposure was made at 10 A. M. in
the month of May; lens used was the rear combination of the
Plastigmat; focallength, 18 inches; stop used, wide open; ex-
posure given was -^ second; plate used, 5x7 Orthonon; de-
veloper, rodinal. The diffused focus was obtained by focus-
ing for foreground; the printing process was carbon. This
negative was worked on by making positives and negatives to
increase contrast and to print in the sky, and afterwards the
picture was enlarged to 8 x 10. Picture was mounted on black
mount.
Study No. II, title, "Sand Dune," by J. S. Neary, Tren-
ton, N. J. This picture was taken about 5 o'clock, with a
Goerz lens fitted to a 6^x8^ camera; plate used was double
coated, developed in ortol, and with no after manipulation.
Study No. 12, title, "The Uphill Road," by Geo. H.
Scheer, M. D., Sheboygan, Wis. This picture was made on
a very bright sunny day, with good clouds in the sky, at
about 3 P. M., in the month of July. The lens used was
Rapid Rectilinear, worked wide open ; plate used was Ortho-
non ; exposure given, ^ second, with a Burke & James Ray
Filter. Plate was developed by tank development in 25-
minute-pyro formula. The negative was enlarged from an
altered negative. Enlargement was made on Platinoid Bro-
mide, the sky portion receiving somewhat longer exposure
than the rest of the picture.
Study No. 13, title, "A Tokio Waterway," in Tokio,
Japan, by William H. Phillips, Liverpool, Ohio. Camera
346 Library of Practical Photography^.
used was a No. 3 Folding Pocket Kodak; lens used, Goerz 5
inch focus, Series 3 ; negative was made on non-curling film,
developed in Pyro Soda developer. Print is an enlargement on
Royal Bromide, size 11x16 inches, developed with rodinol
strong solution — one part rodinol, six parts water.
Study No. 14, title, "Ocean Waves," by J. S. Neary,
Trenton, N. J. Exposure was made about 6 A. M.; lens
used was Goerz, fitted to a 6^x8^ Century camera; plate used,
double coated; developed with ortol, with no after manipu-
lation. Print was mounted on carbon black cardboard.
348
Library of Practical Photograph}).
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- D
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i^S'^C 4)
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CO CO
M'
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c4 ce o c
OS
2 o
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tsj
356
Library of Practical Photography.
TABLES OF THE SYMBOLS, CLASSES OR GROUPS.
Atomic and Equivalent Weights of the Elements.
Namb.
§
CO
Group.
h
n
<
S5 .
< a
W
Aluminum
Al
Sb
As
Ba
Be
Bi
B
Br
C
Cd
Cs
Ca
Ce
CI
Cr
Co
Cu
Di
E
F
Ga
Ge
G
Au
H
In
I
Ir
Fe
La
Pb
Li
Mg
Mn
Hg
Mo
m (IV)
III (V)
III (V )
II
II or III
III (V)
III (V)
I (in, V, VII)
IV
II
I
II
III (IV)
I (III, V, VII)
IV (VI)
II (IV)
II
III
III
I
IV
IV
II
I (III)
I
III (IV?)
I, III, V, VII
II (IV, VI)
II (IV, VI)
III
II (IV)
I
II
II (IV, VL VII)
II
VI
21 A
120.0
75.0
137.0
9.4
208.0
11.0
80.0
12.0
112.0
133.0
40.0
140.0
35.5
52.2
58.8
63.4
145.0
166.0
19.0
69.0
72.2
9.4
196.0
1.00
113.4
127.0
193.0
56.0
138.5
207.0
7.0
24.4
55.0
200.0
96.0
13 7
Antimony ( Stibium )
120 0
Arsen
75 0
Barium
68 5
Berry Ilium ( Glucinum )
Bismuth
4.7
208 0
Boron
11.0
Bromine
80.0
Carbon
6 0
Cadmium
56 0
Caesium
133 0
Calcium
20.0
Cerium
46 0
Chlorine
35 5
Chromium
26 1
Cobalt
29 4
Copper
31 7
Didymium
Erbium
Fluorine
19 0
Gallium
Germanium
Glucinum
9 4
Gold
196 0
Hydrogen
1.00
Indium
37.8
Iodine
127.0
Iridium
99 0
Iron
28 0
Lanthanium
46.3
Lead ( Plumbum )
103 5
Lithium
7 0
Maenesium
12 2
Manganese ,
27.5
Mercury
100 0
Molybdenum
46.0
Appendix.
357
Table of the Symbols, Etc.— Continued.
Niobium ( Columbium ) .
Nickel
Nitrogen
Osmium.
Oxygen. .
Palladium
Phosphorus
Platinum
Potassium (Kalium)
Rhodium. . ,
Rubidium . ,
Ruthenium.
Scandium
Selenium
Silicon ( Silicium).
Silver ( Argentum )
Sodium (Natrium )
Strontium
Sulphur
Tantalum
Tellurium
Thallium
Thorium
Tin (Stannum)
Tugsten (Wolfram)
Uranium
Vanadium .
Ytterbium.
Yttrium . . .
Zinc
Zirconium.
Nb
Ni
N
Os
O
Pd
P
Pt
K
Rh
Rb
Ru
Sc
Se
Si
Ag
Na
Sr
S
Ta
Te
Tl
Th
Sn
W
U
Yt
Y
Zn
Zr
Group.
V
II (IV)
in (V)
II(IV,VI,VII)
II (IV?)
(II, IV, VI)
III (V)
II (IV, VI)
I
II (VI)
I (V)
II(IV,VI,VIII)
II(IV,VI,VII)
II (IV, VI)
IV
I
I
II
II (IV, VI)
V
II (IV, VI)
I (III)
IV
II, IV
IV, VI
VI (IV)
III (V)
IV
II
II
IV
94.0
58.8
14.0
199.0
16.0
106.0
31.0
196.0
39.0
103.5
85.4
101.4
43.9
79.0
28.0
108.0
23.0
87.5
32.0
182.0
127.0
204.0
232.5
118.0
184.0
240.0
51.2
172.6
89.5
65.0
90.0
2«
18.8
29.4
14.0
99.5
8.0
53.25
31.0
98.7
39.0
52.2
85.4
52.2
52.2
39.7
14.0
108.0
23.0
43.7
16.0
36.4
64.0
204.0
57.87
59.0
92.0
60.0
51.2
17.1
30.85
32.6
44.8
m
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Appendix,
361
UNITBD STATES WEIGHTS AND MEASURES.
According to Existing Standards.
LINEAL.
12 inches = 1 foot.
3 feet = 1 yard.
5.5 yards = 1 rod.
40 rods = 1 furlong.
8 furlongs = 1 mile.
Inches. Feet. Yards. Rods. Fur's. Mile.
12= 1
36 = 3 = 1
198 = 16.5 = 5.5 = 1
7,920 =660 = 220 = 40 = 1
63,360 = 5,280 = 1,760 = 320 = 8 = 1
SURFACE — LAND.
144 sq. ins. = 1 sq. ft.
9 sq. ft. = 1 sq. yard.
30.25 sq. yds. = 1 sq. rod,
40 sq. rods = 1 sq. rood.
4 sq. roods = 1 acre.
640 acres = 1 sq. mile.
Feet.
9 =
272.25 =
10,890 =
43,560 =
Yards.
1 =
30.25 =
1,210 =
4,840 =
Rods. Roods. Acres.
1
40 =
160 =
1
4 =
27,878,400=3,097,600= 102,400 = 2,560= 640
4 gills = 1 pint.
2 pints = 1 quart.
4 quarts = 1 gallon.
VOLUME — LIQUID.
Gills. Pints
32
Gallon. Pints. Ounces
1 = 8 = 128
1 = 16
1
FLUID.
Drachms.
= 1,024 =
= 128 =
= 8 =
1 =
= 8
Minims.
61,440
7,680
480
Gallon. Cub. In.
= 1 = 231
Cubic Centimetres.
= 3,785,435
= 473,179
= 29,574
60 =
3,697
16 ounces, or a pint, is sometimes called a fluid pound.
TROY WEIGHT.
Pound.
1
Ounces. Penny wei
= 12 = 240
1 = 20
1
ghts. Grains.
= 5,760
= 480
= 24
=
Grams.
373.24
31.10
1.56
APOTHECARIES' WEIGHT.
lb.
Pound.
1
S 5
Ounces. Drachms.
= 12 = 96 =
1=8 =
1 =
3 gr.
Scruples. Grains
288 = 5,760
24 = 480
3 = 60
1 = 20
1
=
Grams.
373.24
31.10
3.89
1.30
.06
The pound, ounce, and grain are
the same as in Troy weight.
AVOIRDUPOIS WEIGHT.
Pound.
1
Ounces. Drachms.
= 16 = 256
1 = 16
1
Grains (Troy).
= 7,000
= 437.5
= 27.34
=
Grams.
453 60
2.17
53.87
362 Library of Practical Photography.
ENGLISH WEIGHTS AND MEASURES.
Apothecaries' Weight.
20 Grains = 1 Scruple = 20 Grains.
3 Scruples = 1 Drachm = 60 Grains.
8 Drachms = 1 Ounce = 480 Grains.
12 Ounces = 1 Pound = 5760 Grains.
FLUID MEASURE.
60 Minims = 1 Fluid Drachm.
8 Drachms = 1 Fluid Ounce.
20 Ounces = 1 Pint.
8 Pints = 1 Gallon.
The above weights are usually adopted in formulae.
All Chemicals are usually sold by
Avoirdupois Weight.
27fi Grains = 1 Drachm = 27^ Grains.
16 Drachms = 1 Ounce = 437)^ Grains.
16 Ounces = 1 Pound = 7000 Grains.
Precious Metals are usually sold by
Troy Weight.
24 Grains = 1 Pennyweight = 24 Grains.
20 Pennyweights = 1 Ounce = 480 Grains.
12 Ounces = 1 Pound = 5760 Grains.
Note. — An ounce of metallic silver contains 480 grains, but an ounce of nitrate
of silver contains only 437H grains.
United States Fluid Measure.
Gal. Pints. Ounces. Drachms. Mins. Cub. In. Grains. Cub. C. M.
1 = 8 = 128 = 1,024 = 61,440 = 231. = 58,328.886 = 3,785.44
1 = 16 = 128 = 7,680 = 28.875 = 7,291.1107 = 473.18
1 = 8 = 480 = 1.8047 = 455.6944 = 29.57
1 = 60 = 0.2256 = 56.9618 = 3.70
Imperial British Fluid Measure.
Gal. Pints. Ounces. Drachms. Mins. Cub. In. Grains. Cub. C. M.
1 = 8 = 160 = 1,280 = 76,800 = 277.27384 = 70,000 = 4,543.732
1 = 20 = 160 = 9,600 = 34.65923 = 8,750 = 567.966
1 = 8 = 480 = 1.73296 = 437.5 = 28.398
1 = 60 = 0.21662 = 54.96 = 3-550
Appendix.
363
METRIC SYSTEM OF WEIGHTS AND MEASURES.
MEASURES OF LENGTH.
Denominations and Values.
Equivalents in Use.
10,000 meters.
1,000 meters.
100 meters.
10 meters.
1 meter.
1-lOth of a meter.
1-lOOth of a meter.
1-lOOOthof a meter.
6.2137 miles.
.62137 mile, or 3,280 ft. 10 in.
Hectometer
338. feet and 1 inch.
393.7 inches.
Meter
89.37 inches.
Decimeter
Centimeter
8.937 inches.
.3937 inch.
.0394 inch.
MEASURES OF SURFACE.
Denominations and Values.
Equivalents in Use.
10,000 square meters.
100 square meters.
1 square meter.
2.471 acres.
Are
119.6 square yards.
1,-550. square inches.
MEASURES OF VOI^UME.
Denominations and Values.
Equivalents in Use.
Names.
No. OF
Liters
Cubic Measures.
Dry Measure.
Wine
Measure.
Kiloliter or stere
Hectoliter
Dekaliter
1,000
100
10
1
1-10
1-100
1-1000
1 cubic meter.
1-lOth cubic meter.
10 cubic decimeters.
1 cubic decimeter.
1-lOth cu. decimeter.
10 cubic centimeters.
1 cubic centimeter.
1.308 cubic yards.
2 bu. and 3.35
pecks.
9.08 quarts.
.908 quart.
6.1023 cubic inches.
.6102 cubic inch.
.061 cubic inch.
264.17 gals.
26.417 gals.
2.6417 gals.
1.0567 qts.
.845 gill.
.338 fl. oz.
Liter
Deciliter
Centiliter
Milliliter
"WEIGHTS.
Denominations and Values.
Equivalents
in Use.
Names.
Number
OF Grams.
Weight of Volume of Wat-
er at its Maximum Density.
Avoirdupois
Weight.
Millier or Tonneau
1,000,000
100,000
10,000
1,000
100
10
1
1-10
1-100
1-1000
1 cubic meter.
1 hectoliter.
10 liters.
1 liter.
1 deciliter.
10 cubic centimeters.
1 cubic centimeter.
1-lOth of a cubic centimeter.
10 cubic millimeters.
1 cubic millimeter.
2204.6 pounds.
220.46 pounds.
22.046 pounds.
2.2046 pounds.
3.5274 ounces.
Kilogram or Kilo
Hectogram • ■ • "
Dekagram
15.432 grains.
1.5432 grain.
.1543 grain.
.0154 grain.
Decigram
Milligram
Fbr measuring- surfaces, the square dekameter is used under the term of ARE; the
hectare, or 100 ares, is equal to about 2^ acres. The unit of capacity is the cubic deci-
meter or LITER, and the series of measures is formed in the same way as in the case
of the table of lengths. The cubic meter is the unit of measure for solid bodies, and
is termed STERE. The unit of weight is the GRAM, which is the weight of one cubic
centimeter of pure water weighed in a vacuum at the temperature of four deg. Cent,
or 39.2 deg. Fahr., which is about its temperature of maximum density. In practice,
the term cubic centimeter abbreviated c. c, is generally used instead of milliliter, and
cubic meter instead of l^iloliter.
364 Library of Practical Photography.
Freezing Mixtures.
Reducing the Temperature From
PARTS. Degrees of the Celsius
3 Nitrate of sodium + 4 Water +13.2 deg.
9 Phosphate of sodium + 4 dilute Nitric acid. +10 "
3 Sulphate of sodium + 2 dilute Nitric acid. . + 10 "
1 Nitrate of sodium + 4 Water
1 Chloride of potassium + 4 Water
5 Sal ammoniac + 5 Saltpetre + 16 Water. ... +10 deg.
1 Nitrate of ammonia + 1 Water +10 "
8 Sulphate of sodium + 5 cone. Sulphuric acid +10 *'
1 Sulphocyanate of Potass. + 1 Water +18 "
1 Chloride of sodium + 3 Snow
1 Sal ammoniac + 1 Saltpetre + 1 Water +8 deg.
3 Crystal, chloride of calcium + 1 Snow
1 Snow + 1 dilute Sulphuric acid — 5 deg. — 41
To
— 5.3deg.
— 9
—10
—10.6
—11.8
—12
—15.5
—17
—21
—21
—24
—36
Antidote for Metol Poisoning.
There is a serious drawback to the use of Metol, as with some peo-
ple it brings on an irritating skin trouble, leaving the fingers very sen-
sitive and tender.
As a cure for this trouble, the following is recommended :
Take first Rochelle Salts to open the bowels, and next day use
Swift's Special Specific, (S. S. S.) according to directions for scrofula.
Attention should be paid to the general health, any tendency toward
dyspepsia and constipation at once to be checked.
The following ointment is good and very healing:
Ichthyol 1 dram.
Lanoline 2 drams.
Vaseline 3 drams.
Boracic Acid 2 drams.
A drop of oil of lavender destroys the odor of the ichthyol and lan-
oline, and makes the ointment pleasant. It should be well rubbed into
the skin, and at nights a good plan is to wear cotton gloves so that the
ointment will not rub off nor stain the clothing. The ointment is also
good for cuts and burns.
Another remedy, which, however, is rather severe, is to soak the
hands in a strong solution of salt and vinegar for fifteen minutes. Do
this twice daily for three or four days.
To Remove Stains from tlie Hands.
Dbvklopmknt Stains. — Yield easily to the action of lemon juice.
Nitrate of Silver Stains. — Prepare a solution of water 100 cc. ;
chloride of lime, 25 grms. ; sulphate of soda, 50 grms. Apply with a
tooth-brush.
Pyro Stains. — Wash stained parts with a 10-per-cent. solution of
oxalic acid.
Amidol Stains. — Difficult to remove. Try citric acid.
Nitric Acid Stains. — Apply to stained parts a solution of per-
manganate of potash. Then wash freely.
Appendix. 365
The Conversion of French (Metric) into English Measure.
1 cubic centimeter
=
17 minims.
1 cubic centimeters
=
84
3
=
51
4
=
68
or
1 dram
8 minims
t.
5
=
85
tt
1 "
25
6
=
101
«
1 "
41
7
=
118
a
1 "
58
8
=
135
t<
2 drams 15
9
=
152
<i
2 "
32
10
=
169
'(
2 "
49
20
=
338
<i
5 "
38
80
=
507
<<
1 ounce
0 dram
27 minims,
40
=
676
<<
1 "
3 drams
16
((
50
=
845
14
1 "
6
5
((
60
=
1014
i(
2 ounces
1 0
54
i<
70
=
1183
(<
2 "
3
43
i(
80
=
1352
(C
2 "
6
32
<t
90
=
1521
li
3 "
1
21
(<
100
=
1690
li
3 "
4
10
<{
1000
—
1 liter
—
34 fluid ounces nearly, or 2^ pints,
The Conversion of French (Metric) into English Weight.
The following table, which contains no error greater than one-tenth
of a grain, will suffice for most practical purposes :
1 gram = 15f grains.
2 grams = 30| "
3 " = 46^ "
4 •* = 6l| " or 1 dram If grain.
5 " = 77i " " 1 " 17^ grains.
6 " = 92f " " 1 " 32|
7 " = 108 " " 1 " 48
8 " = 1231 " •• 2 drams 3f
9 " = 138f " •« 2 " 18i
10 " = 154f " " 2 " 34|
11 •' = 169| " " 2 " 49| "
12 " = 185i " "3 " 5i
13 " = 200f " " 3 " 20| "
14 •* =216 " "8 " 36
15 " = 231| " " 3 " 51| "
16 " = 247 " " 4 " 7 "
17 " = 262f " " 4 " 22| "
18 " = 2774 " " 4 " 374
19 " = 293i " " 4 " 53i "
20 " = 308f " "5 " 8i "
80 " = 463 " " 7 " 43 "
40 " = 617^ " "10 " 17i
50 " = 771| " "12 " 51|
60 " = 926 " "15 " 26 "
70 " = 10804 " "18 " 04
80 " = 12344 " "20 " 341
90 " = 1389 " "23 " 9 "
100 " = 15434 " "25 " 434 "
1000 " = 1 kilogram = 82 oz., 1 dr., 124 gr-
GENERAL INDEX
VOLUME II.
The numbers in this index refer to paragraphs in all cases,
excepting where the word "Page" precedes the number. (A)
signifies that the reference will be found in the Appendix.
Accelerator, Carbonate of Soda 25
Acetone Developer for Tray or Tank — Pyro-Metol 597
Acetone Pyro Developer, Formula for 577
Acetone Pyro Developer for X-Ray Plates 588
Acetone, Pyro-Metol With 583
Acid Fixing Bath 116-118, 417, 526, 589, 686, 775, 801-804
Acid, Nature of Nitric 46
Acid, Pyrogallic 46
Acid, Sulphuric 46
Action of Carbonate of Soda 25, 102
Action of Developers, Chemical 51, 104-106
Action of Light on Dry Plates as Compared to Printing-out
Paper 192, 193
Action of Old Developer 35, 36
Action of Pyro Developer 24, 108
Action of Reducer 262
Adurol-Metol for Negatives and Lantern Slides 435-438
Advanced Development of Over- Exposures 240-256
Agents, Effects of Different Developing 457-459
Alkali in Developer, Action of Page 32
Alteration of Developing Formula for Different Brands of
Plates 55, 56
Alternating Developer — Hydroquinone-Eikonogen 422
Alum Hypo Bath Formula Page 139
Alum, Nature of 288
Amidol, Factor for Factorial Development With 460
Amidol Stains, To Remove (A) Page 364
Ammonia Developing 439-447
Ammonia Developing Formula 442
Ammonia, Formula for Reducing With Persulphate of 277
367
368 Library of Practical Photography.
Antidote for Metol Poisoning (A) Page 364
Antidotes, Table of Poisons and (A) Page 358
Apparatus for Developing 1
Appendix Pages 348-365
Applying the Reducer to Films 304-306
Applying the Reducer With the Brush 296
Applying the Reducer With Finger or Tuft of Cotton 299, 300
Ascertaining the Factor 471-473
Atomic Weights (A) Pages 348-355
" At Peace," Study No. 4 Page 79
Avoid Granular Surface by Returning the Plate to the Hypo
Bath When Reducing 298
Avoid Printing from Plates Lacking Strength 144
Bath, Alum Hypo Page 139
Bath, Fixing 57, 685
Bath Fixing, Acid 116-118, 417, 526, 686
Bath, Hardening 589
Best Time to Reduce Plates or Films 264
Bottles, Stock Solution 12
Box for Plates in Dark Room, Changing 20
Box, Washing 16, 516
Box, Washing, Illustration of Pages 18, 211
Bromide and Negative Enlarging 21
Bromide of Potassium, Nature of 46, 421
Bromide of Potassium, Preparing a 10% Solution of 201
Bromide of Potassium, Use of 32
Bromide of Potassium Solution, Mixing 34
Brush, Applying the Reducer with the 296
Carbonate of Potash in Pyro Developer 768, 776
Carbonate of Soda, Action of 25, 102
Carbonate of Soda, Nature of 46, 419
Carbonate of Soda Stock Solution for Pyro Developer 47
Caustic Soda, Nature of 420
Changing Box for Plates in Dark Room 20
Characteristics of the Principal Photographic Developers (A) . .
Page 360
Chemical Action of Developers 51, 104-106
Chemical Fog 35, 36, 431
Chemicals, Developing 13
Chemical Symbols, Atomic Weights and Solubilities of (A) . .
Pages 348-355
Class of Negatives That Can Be Improved By Doctoring 292
Clearing Solution for Intensifier 136
Clearing Solution Can Be Used Repeatedly Without Renewing 147
Clearing the Plate After Intensifying 173, 174
Clearing the Plate or Film After Reducing 270
General Index. 369
Color of Plate, Proper 50
Commercial Ortho Plates, Seed's 702
Commercial Photography, Cramer Plates for
603, 605, 610, 615, 624, 634
Commercial Photography, Over-exposures in 243
Commercial Photography, Seed's Plates for 696, 701, 703
Commercial Photography, Special Pyro Developing for 357-379
Commercial Photography, Universal Developer for 322-337
Comparative Speed of Cramer Plates 640
Construction of Sensitive Emulsion 189-191
Contrast Developer, Formula for 585
Contrast Plates, Cramer's 634, 635
Correct Exposure, Example of Page 101
Cramer Plates, Comparative Speed of 640
Cramer Plates — Development of Normal Exposures 561-566
Cramer Plates, DiflFerent Brands and Uses of 600-641
Cramer Plates, Double Coated Non-halation 624-627
Cramer Plates, Dry Plate Don'ts for 569-576
Cramer Plates, Exposure for 556-560
Cramer Plates for Commercial Photography
603, 605, 610, 615, 624, 634
Cramer Plates, Instruction by Manufacturers of 551-641
Cramer Plates, Isochromatic 605-623
Cramer Plates, Lantern Slide 637-639
Cramer Plates, Speed of 555
Cramer Plates, Standard Formulae for 577-599
Cramer Plates— Stripping 627-629
Cramer Plates, Tank Developers for 596-599
Cramer Plates, The Best Developers for 567, 568
Cramer Plates — Transparency 636
Cramer Plates, Trichromatic 619-623
Cramer Plates, X-Ray 630-633
Crispness and Snap of Negatives 37
Dark Room, A Convenient 14
Dark Room, Changing Box for Plates in 20
Dark Room, Floor Plans of Page 15
Dark Room Light 455, 738, 741
Dark Room Plans Pages 15, 16, 21
Dark Room, Sectional View of Page 16
Dark Room Shelving 18
Dark Room, Size of 10
Dark Room, Use of 2, 8
Dark Room Ventilation 11
Data on Negative Envelope 7
Department of Printing and Developing in Dark Room 19
Department of Enlarging in Dark Room 20
II — 19
370 Library of Practical Photography.
Developed, Judging When Plate is 40-44
Developed Too Far Before Restraining, Plate 206
Developer, Action of Pyro 34, 108
Developer, Ammonia 439-447
Developer, A Ten Minute Factorial 468
Developer, A Twenty Minute Factorial 469
Developer, A Twenty-five Minute Factorial 470
Developer, Carbonate of Potash in Pyro 768, 776
Developer, Characteristics of the Principal Photographic (A) . .
Page 360
Developer, Chemical Action of 51, 104-106
Developer, Contrast 585
Developer, Definition of Page 9
Developer, Flowing Plate With 2
Developer for Commercial Photography, Special Pyro 357-379
Developer for Commercial Photography, Universal 322-337
Developer for Cramer Plates, Tank 596-599
Developer for Cramer Plates, The Best 567, 568
Developer for Exterior Views, Special Pyro 358
Developer for Lantern Slides 426-438, 584
Developer for Line Work 586
Developer for Tank Development 504, 596-599
Developer for Transparencies 584
Developer for X-Ray Plates 587, 588
Developer, Hammer's Dry Powder 794-797
Developer, Hydroquinone-Eikonogen 413-425
Developer, Non-Staining and Non-Poisonous 413-425
Developer, Ortol 579, 683
Developer, Pyro- Acetone 577
Developer, Stock Solutions for Pyro 47
Developer, Temperature of Page 32
Developer, Use of Old 33
Developer, Use of Old or Once Used 196
Developers, General Notes on Page 32
Developers for Cramer Plates 577-597
Developers for Hammer Plates 767-791
Developers for Seed Plates 678-686
Developing Agent, Preservative of 25
Developing Agents, Effect of DiflFerent 457-459
Developing Apparatus 1
Developing Chemicals 13
Developing Different Brands of Plates 198-200
Developing, Difficulties in — Ordinary Dry Plate 62-94
Blisters 77
Color of Negative, Proper 69
Dense Negatives 86
General Index. 371
Detail in Shadows, Lack of 63
Development Uneven 76
Dirt and Scum on Negative When Dry 93
Discolored Hypo Bath 72
Finger Marks 74
Fixed, Judging When Plate is 71
Frilling 75
Granular Negatives, Film Having a Grainy Appearance.. 90
Hypo Bath Discolored 72
Judging if Plate is Over-timed 67
Judging if Plate is Under-timed 66
Judging Proper Strength of Negative 70
Judging When Plate is Fixed 71
Lack of Detail in Shadows 63
Large Transparent Spots, Triangular in Shape and Ir-
regular in Size 81
Marks, Finger 74
Mottled Negatives 73
Negatives, Dense 86
Negatives Drying Too Slowly 91
Negatives Evenly Developed, But Drying Unevenly 92
Negatives Full of Dirt and Scum When Drying 93
Negatives Granular, Film Having Grainy Appearance ... 90
Negatives, Mottled 73
Negatives, Parallel Lines on 87
Negatives, Thin 85
Negatives, Yellow 84, 121
Negatives Yellow, Even With Sodas of Proper Strength 9
Over-timed, Judging if Plate is
Parallel Lines on Negative 87
Part of Plate Stained Yellow 88
Pin Holes and Spots 78
Plate Flashing Up Quickly and Darkening All Over at
Once, Detail Very Dim 65
Plates Slow in Starting to Develop 62
Producing Proper Contrast 68
Proper Color of Negative 69
Properly Exposed Plates Developing Slowly 64
Purple or Dark Opaque Spots, Regular in Size But Comet
or Irregular in Shape 83
Round Transparent Spots 79
Scum and Dirt on Negatives When Dried 93
Shadows Lack Detail 63
Slow Development of Properly Exposed Plates 64
Small Transparent Spots, Resembling Little Particles of
Lint and Dust 82
372 Library) of Practical Photography.
Small Transparent Spots Triangular in Shape and Irre-
gular in Size 80
Spots and Pin Holes 78
Spots and Streaks Almost Transparent on Plate After
Drying 89
Spots Regular in Size But Comet or Irregular in Shape,
Purple or Dark Opaque 83
Spots Resembling Little Particles of Lint and Dust,
Small Transparent 82
Spots, Round Transparent 79
Spots, Triangular in Shape and Irregular in Size, Large
Transparent 81
Spots, Triangular in Shape and Irregular in Size, Small
Transparent 80
Streaks and Spots Almost Transparent on Plates After
Drying 89
Strength of Negatives, Judging Proper 70
Thin Negatives 85
Transparent Spots, Round 79
Transparent Spots, Resembling Little Particles of Lint
and Dust, Small 82
Transparent Spots Triangular in Shape and Irregular in
Size, Large 81
Transparent Spots Triangular in Shape and Irregular in
Size, Small 80
Uneven Development 76
Uneven Drying of Unevenly Developed Negatives 92
Under-timed, Judging if Plate is 66
Yellow Negatives 84-121
Yellow Negatives, Even With Sodas of Proper Strength 94
Yellow, Part of Plate Stained 88
Developing Extreme Over-Exposures 202, 203
Developing, Factorial 448-478
Developing, Factorial — Difficulties 479-483
Controlling the Temperature 483
Judging Time of Appearance 479
Obtaining the Factor 480-482
Temperature, Controlling the 483
Developing Formula, Regular Pyro 47-49
Developing Formula for Overcoming Halation 370-376
Developing Formula, Universal 328-331
Developing in Dark Room, Department of Printing and 19
Developing Instantaneous Exposures With Ammonia Developer 439
Developing Light 17, 455, 738-741
Developing Light, Nature of 8, 9
Developing of Doubtful Exposures 109, 110
General Index. 373
Developing Outfit 12
Developing Over-exposures 187-210
Developing Over-exposures — Advanced 240-256
Developing Over-exposures — Difficulties 211-239
Action of Developer on Over- Exposed Plates 211-216
Clearing Stained Negatives 236
Desired Amount of Bromide to Use 229
Determining When to Check Development of a Plate
Started in Normal Developer 235
Developing Plates of Doubtful Exposure 217
How Far to Carry Development of Plates That Are
Over-exposed 227, 228
How Long a Plate Should Remain in the Bromide. . .230, 231
Judging During Development How Much the Plate is
Over-exposed 218-220
Large Transparent Spots 239
Mottled Negatives 238
Obtaining Clear Shadows 222-226
Obtaining Desired Contrast of Over-timed Plates 221
Preserving Old Developer 234
Transparent Spots, Large 239
Uneven Development 237
Using Old Developer 233
Yellow Negatives 232
Developing Papers, Light for Printing 19
Developing, Process of 2, 103
Developing, Restraining the Plate Too Quickly When 205
Developing Sink 15
Developing Seed Plates— Difficulties 742-762
Blurred Opaque Finger Marks or Spots 759
Developer, The 762
Development, Slowness of 748
Drying the Negatives 742
Flat Negatives 743-745
Fog 750-752
Frilling and Softening of the Film 746
Granularity of Negatives 760
Making Up of Developing Solutions, The 761
Negatives, Drying 742
Negatives Flat 743-745
Negatives, Granularity of 760
Opaque Spots and Lines 757
Slowness of Development 748
Small Opaque Spots 758
Softening and Frilling of the Film 746
Spots and Lines, Opaque 757
374 Library of Practical Photography.
Spots, Small and Large Round Opaque 754, 755
Spots, Small Opaque 758
Spots, Triangular Transparent 756
To Clean a Lens 753
Too Much Contrast 749
Triangular Transparent Spots 756
Weakness of Image 747
Developing Solutions, Life of 527
Developing, Special Pyro — Difficulties 398-412
Color of Plate Too Gray 405
Development Slow; Image Over Five Minutes in Making
Appearance 398
High Lights Too Strong, Losing All Detail 404
How to Treat a Plate Which Has Been Sufficiently Ex-
posed, But Too Much Carbonate Has Been Added
to the Developer 408
How to Treat a Plate Which Has Not Been Sufficiently
Exposed so as Not to Lose the Negative Entirely.. 407
Image Flashing Up at Once 399
Judging the Proper Amount of Carbonate to Use When
First Starting to Develop 411
No Detail in Shadows 403
Obtaining Proper Strength 400
Plate Appearing to Develop Properly, But the Highest
Lights Not Gaining Sufficient Strength 412
Plate Developing in Streaks, Uneven Development 409
Plate Fogging 401
Plate Frilling 406
Plate Very Thin After Fixing 402
Transparent and Semi-Transparent Spots in the Negative 410
Developing Stains, To Remove (A) Page 364
Developing, Tank or Stand 484-530
Developing Tanks 511-513, Pages 22ia-224q
Developing Tank— Difficulties 531-548
Negatives Contrasty 537
Negatives Developing Flat 538
Negatives Full of Detail, But Very Thin 539
Negatives Too Blue 541
Negatives Too Yellow When Developed in a Pyro De-
veloper 540
Pin Holes 535
Plates Developing Contrasty in Hydro-Metol Developer
After the Bath Has Been Used for Some Time. . . . 543
Plates Developing in Streaks 534
Plates Developing Too Fast 532
Plates Developing Unevenly 533
General Index. 375
Plates Developing Too Slowly 531
Scum Gathering on the Developer While in the Tank... 546
Sediment Gathering in a Developing Tank and Bottle
Which Contains Hydro-Metol Developer 547
Some Plates Develop Quicker Than Others 545
Spots and Pin Holes That Are Not Caused by Air-bells.. 536
Testing Development for Temperature 548
Top Edges of Plates Not Developed 544
When Developing With Pyro Plates Develop to a Certain
Stage and Then Stop 542
Developing Tanks, Illustrations of Pages "H, 224(/ to 224ifc
Developing, Theory of 22-25
Developing Under-exposures 95-118
Developing Under-exposures, Practice Work 119
Developing Under-exposures — Difficulties 120-128
Blisters Forming on Plate, Little 125
Detail, Shadows Lacking in 123
Flat Negatives 127
Fogging During Development, Negatives 126
Frilling, Plate 124
Grain, Negative Drying With Too Much 120
Little Blisters Forming on Plate 125
Negative Drying With Too Much Grain 120
Negative Flat 127
Negative Fogging During Development 126
Negative Lacking Strength and Snap 128
Plate Developing Only Partly and Then Stopping 122
Plate Frilling 124
Shadows Lacking Detail 123
Developing, Universal 322-341
Developing, Universal — Difficulties 342-356
Developer Discoloring After Having Been Prepared Only
a Short Time 343
Developing Heavy Shadow Lightings 342
No Detail in High Lights 354, 355
Negatives Drying With a Coarse Grain 345
Negatives Too Strong in Color — Yellow 347
Negatives Which Appeared Sufficiently Developed Very
Thin After Fixing 349
Plate Developing Flat 353
Plate Inclined to Develop Contrasty 351
Proper Detail in Shadows 350
Retaining Soft Detail in Shadows 356
Securing Half-tones in High Lights 352
Shadows Fogging During Development 346
Testing Old Sulphite of Soda Solution 348
376 Library of Practical Photography.
Developing, Use of Two Trays for 197
Developing With Diflferent Factors Regulates Speed of De-
veloper 461
Development, Factorial 448-478
Development, Factorial — Practice Work 476-478
Development, Latitude in Tank 486-490
Development of Normal Exposures (Cramer Plates) 561-566
Development of Over-exposures — Advanced 240-256
Development of White Drapery, Example of Page 155
Development of White Drapery Portrait Negatives, Special 380, 397
Development, Restraining 32
Development Starts Slowly 62
Development, Tank (Pyro) 107, 504
Development, Washing After 799
Difficulties — Factorial Development (See Developing, Factorial)
479-483
Difficulties — Developing Over-exposures (See Developing, Over-
exposures) 211-239
Difficulties — Developing Seed Plates (See Developing, Seed
Plates) 742-762
Difficulties — Developing Under-exposures (See Developing,
Under-exposures) 120-128
Difficulties — Dry Plate Developing (See Developing, Ordinary
Dry Plate) 62-94
Difficulties — Intensifying (See Intensifying) 155-167
Difficulties — Local Intensifying (See Intensifying, Local).. .179-186
Difficulties — Reducing (See Reducing) 307-321
Difficulties — Special Developing (See Developing, Special) . .398-412
Difficulties — Tank Developing (See Developing, Tank) 531-548
Difficulties — Under-exposures (See Developing Under-exposures)
120-128
Difficulties — Universal Developing (See Developing, Universal)
342-356
Discoloring of Hypo Bath 28
Doctoring, Class of Negatives That Can Be Improved By 292
Doctoring White Drapery Negatives 293, 294
Double Coated Plates 45
Double Coated Plates, Cramer's 624-627
Double Coated Plates, Hammer's 859-861
Double Coated Plates, Seed's 693-695
Doubtful Exposures, Developing of 109, 110
Drapery, Doctoring White 293, 294
Drapery, Example of Developing White Page 155
Drapery Portrait Negatives, Special Developing of White. .380-397
Dr. Scott's Table of Comparative Exposures 863
Dry Plate Emulsion Page 9
General Index. 377
Drying Negatives 6, 807
Drying Negatives Page 32
Dry Plate Don'ts 569-576
" Dull October Day, A," Study No. 8 Page 159
Edinol, Factor for Factorial Development With 460
Effect of Different Developing Agents 457
Effect of Pyro Page 32
Eikonogen, Factor for Factorial Development With 460
Eikonogen, Formula for Hydroquinone and 416, 581, 681, 780
Eikonogen Developer, Altering 422
Eikonogen-Hydroquinone Developer for Lantern Slides 784
Eikonogen-Hydroquinone — Non-staining and Non-poisonous
Developer 413-425
Eikonogen, Nature and Action of 418
Elements, Atomic Weights of the (A) Pages 356, 357
Emulsion, Construction of Sensitive 189-191
Emulsion, Dry Plate Page 9
Emulsion, Restraining the Sensitive 194
English Measure, Conversion of Metric Into (A) Page S65
English Weight, Conversion of Metric Into (A) Page 365
Enlarging, Bromide and Negative 21
Enlarging Department in Dark Room 20
Experiments, Plates to Use for Intensifying 153, 154
Exposure, Development of Normal 561-566
Exposure, Development of Over- 563
Exposure, Example of Correct Page 101
Exposure, Example of Over- Page 115
Exposure, Extreme Under- 39
Exposure for Cramer Plates 556-560
Exposure, Practical Advice on 733-737
Exposure Table for Hammer Plates 840
Exposure, Under- 38-44
Exposures, Developing of Doubtful 109, 110
Exposures, Development of Normal 561-566
Exterior Views, Special Pyro Developer for 358
Factorial Developer, A Ten Minute 468
Factorial Developer, A Twenty Minute 469
Factorial Developer, A Twenty-five Minute 470
Factorial Developer, Factors for 460
Factorial Developer, Formula for 461, 462, 508
Factorial Developer, Preparing the Stock Solution for 463-465
Factorial Developer, Temperature of 452-454
Factorial Developing Solutions, Mixing 466
Factorial Development 448-478
Factorial Development — Difficulties 479-483
Factorial Development, Metol-Hydroquinone 429-434
378 Library of Practical Photography.
Factorial Development — Practice Work 476-478
Factorial Development, Retaining Normal Temperature in. ..474,475
Factors for Factorial Development of Seed Plates 675
Factors Regulate Speed of Developer, Developing With Dif-
ferent 461
Factors, Table of 460
Factors, The 449
Factors, Obtaining the 450, 467, 471-473
Ferrotype Process 995-1030
Ferrotype Process^ — Apparatus and Material 997-1004
Ferrotype Process — Baths, Preparing Silver 1010-1012
Ferrotype Process — Bromide of Ammonium 1009
Ferrotype Process — Bromide of Cadmium 1006
Ferrotype Process — Bromo-Iodize 1007
Ferrotype Process — Bromo-Iodizer 1009
Ferrotype Process — Camera 997-1000
Ferrotype Process — Camera Stands 1001
Ferrotype Process — Collodion, Making the 1005, 1006
Ferrotype Process — Collodion, Plain 1008
Ferrotype Process — Collodionizing the Plate 1017
Ferrotype Process — Dark-room 1002
Ferrotype Process — Definition 996
Ferrotype Process — Developer, Formula for 1013-1016
Ferrotype Process — Developer, Preparing the 1015
Ferrotype Process — Developing 1021-1023
Ferrotype Process — Drying 1025
Ferrotype Process — Drying After Varnishing 1029, 1030
Ferrotype Process — Ether 1006, 1008
Ferrotype Process — Exposing 1020
Ferrotype Process — Fixing 1024
Ferrotype Process — Formula for Developer 1013-1016
P'errotype Process — Gasoline Varnish 1027, 1028
Ferrotype Process — Gun-cotton 1006
Ferrotype Process — Introduction 995, 996
Ferrotype Process — Iodide of Ammonium 1006
Ferrotype Process — Iodide of Cadmium 1006, 1009
Ferrotype Process — Iron Developer 1013
Ferrotype Process — Making the Collodion 1005, 1006
Ferrotype Process — Materials 997-1004
Ferrotype Process — Nitrate of Silver 1011
Ferrotype Process — Plain Collodion 1008
Ferrotype Process — Plate, Collodionizing the 1017
Ferrotype Process — Plates 1004
Ferrotype Process — Preparing Silver Baths 1010-1012
Ferrotype Process — Preparing the Developer 1015
Ferrotype Process — Sensitizing 1018, 1019
General Index. 379
Ferrotype Process— Silver Baths, Preparing 1010-1012
Ferrotype Process — Silver Nitrate 1011
Ferrotype Process — Stand, Camera 1001
Ferrotype Process— Tintypes, Gasoline Varnish for 1027, 1028
Ferrotype Process — Varnish, Gasoline 1027, 1028
Ferrotype Process — Varnishing 1026
Ferrotype Process — Varnishing, Drying After 1029, 1030
Filling Plate Holders 554
Film Developing Holder, The 510
Film, Applying the Reducer to 304-306
Film, Stripping 863
Filters, Cramer's Light 612-617
Filters, Hammer's Light 810
Filters, Seed's Light 713-725
Fixing 4, 800
Fixing Bath 57, 685, 775, 801, 804
Fixing Bath, Acid 116-118, 417, 589, 686
Fixing Tank 514
Fixing Tank, Illustration of Page 211
Fixing Plate After Intensifying 150
Fixing, Washing After 5, 806
Fixing, Theory of 26
Flowing Plate With Developer 2
Fluid Weights and Measures 862
Fog, Chemical 35, 36, 431
Formalin 805
Formula for Acid Fixing Bath 686, 775, 801-804
Formula for Ammonia Developer 442
Formula for Alum Hypo Bath Page 139
Formula for Cramer Dry Plates 577-597
Formula for Contrast Developer 585
Formula for Factorial Development 461-462
Formula for Hammer Plates 767-791
Formula for Hydroquinone-Eikonogen Developer. .416, 581, 681, 780
Formula for Intensifying Solution 135
Formula for Lantern-slide Developer 584, 783-793
Formula for Metol-Adurol Developer 435-438
Formula for Metol-Hydroquinon Developer. . .430-434, 580, 682, 779
Formula for Metol-Hydroquinon Factorial Developer 470
Formula for Ortol Developer 579, 683
Formula for Overcoming Halation, Developing 370-376
Formula for Pyro- Acetone Developer 577
Formula for Pyrocatechin Developer 783
Formula for Pyro Developer, Regular 47-49, 578, 678, 767, 777
Formula for Pyro Developer With Carbonate of Potash 768, 776
Formula for Pyro-Metol Developer 582, 684, 781, 782
380 Library of Practical Photography.
Formula for Pyro-Metol-Tolidol Developer 778
Formula for Reducing With Red Prussiate 265
Formula for Reducing with Persulphate of Ammonia 277
Formula for Seed's Panchromatic Plates 732
Formula for Seed's Plates 678-689
Formula for Strengthening Negatives of Uncertain Fixing. .148, 149
Formula for Tank Development 504, 505, 596-599
Formula for Tank Development With Metol Hydroquinone. . . .523
Formula for Tank Development with Glycine 524
Freezing Mixtures (A) Page 364
General Notes on Developers Page 32
Glycine Formula for Tank Developers 524
Halation 808
Halation, Developing Formula for Overcoming 370
Halation — Example of Overcoming in Interior Photography..
Page 145
Halation — Method of Overcoming by Means of Special De-
velopment 365-379
Hammer's Double Coated Non-halation Plates 859-861
Hammer's Dry Powder Developer 794-797
Hammer's (Dry Powder) X-Ray Developer 828-830
Hammer's Extra Fast Plates 831-833
Hammer's Fast Plates 834-839
Hammer's Lantern Slide Plates 846-851
Hammer's Orthochromatic Plates 810-819
Hammer's Plates, Developer for 767-791
Hammer's Plates, Exposure Table for 840
Hammer's Plates, Formula for 767-791
Hammer's Plates, Instruction by Manufacturers 763-863
Hammer's Slow Plates 841-845
Hammer's Special Extra Fast Plates 820-824
Hammer's Transparency Plates 852-858
Hammer's X-Ray Plates 825-827
Hands, To Remove Stains from the (A) Page 364
Hardening Bath 589
Holder, Filling 554
Holder, The Film Developing 510
How the Studies Illustrating This Volume Were Made
Pages 343-346
How to Keep the Reducing Solution 272
Hydro-Metol Factorial Development 431
Hydrometer, Use of 53
Hydroquinone Developer for Lantern Slides 791
Hydroquinone Developer, Altering the 422
Hydroquinone-Eikonogen Developer, Formula for
416, 581, 681, 780
General Index. 381
Hydroquinone-Eikonogen Developer for Lantern Slides 784
Hydroquinone-Eikonogen for X-Ray Plates 587
Hydroquinone-Eikonogen Non-staining and Non-poisonous De-
veloper 413-425
Hydroquinone, Factor for Factorial Development With 460
Hydroquinone for Over-exposures, Use of 422-425
Hydroquinone, Nature and Action of 418
Hydroquinone-Metol Developer, Formula for.. 430-434, 580, 682, 779
Hydroquinone-Metol for Factorial Development 495, 496
Hydroquinone-Metol for Negatives and Lantern Slides 426-434
Hydroquinone-Metol Formula for Tank Development 523
Hypo Bath, Discoloring of 28
Hypo Bath Formula, Alum Page 139
Hypo in Persulphate Bath, Traces of 281
Hypo-Sulphite of Soda, Nature of 46, 287
Image When Developing, Appearance of the 2, 252, 253
Image Invisible Page 9
Image Visible Page 9
Instantaneous Exposures With Ammonia Developer, Developing 439
Intensifier, Clearing Solution for 136
Intensifier, Preparing the Plate to Receive 137, 138
Intensifier, When to Apply the Local 177, 178
Intensifier, When to Stop Action of the 140
Intensifying 129-154
Intensifying, Clearing the Plate After 173, 174
Intensifying, Difficulties in 155-167
Ammonia Clearing Bath, When to Use 160
Appearance of Old Negatives Which Have Not Been
Properly Fixed and Washed 166
Intensifier Will Not Work After Using a Few Times... 164
Intensifying Solution Becomes Milky 165
Judging When Plate is Carried Far Enough in Mercury
Intensifier 156
Negatives Appearing Oily 155
Negatives Intensifying in Streaks 162
Negatives Intensifying Unevenly 157
Negatives Not Clearing in Clearing Solution 159
Negatives Stained After Going Through Clearing Bath —
Sulphite of Soda Solution 158
Oily, Negatives Appearing 155
Removing Varnish 167
Shadows Remaining Weak After Intensifying 161
Small Opaque Spots Irregular in Shape and Size 163
When to Use Ammonia Clearing Bath 160
Intensifying Experiments, Plates to Use for 153, 154, 176
Intensifying, Fixing the Plate After 150
382 Library of Practical Photography.
Intensifying Formula 135
Intensifying, Light to be Used While 145
Intensifying, Local 168-178
Intensifying, Difficulties in Local 179-186
Applying Intensifying Glycerine Intensifier to Dry Nega-
tives Without Effect 185
Intensifier Spreading, Glycerine 186
Intensified Portions Stained After Going Through Clear-
ing Solution 182
Intensifier Spreading 180
Intensifying, Parts Not Improved by 179, 183
Judging When iMegative is Sufficiently Intensified 181
Parts Not Improved by Intensifying 179, 183
Plate Refusing to Clear in Clearing Bath 184
Intensifying, Fixing the Plate After 150
Intensifying, How to Proceed With 169
Intensifying, Methods of 133
Intensifying Negatives While Dry, Locally 175
Intensifying, Object of 129
Intensifying, Plate Becoming Stained by 142
Intensifying, Re- 139
Intensifying, Removing Varnish With Turpentine Before 152
Intensifying, Rocking Tray While 141
Intensifying Solution is Used, Why a Weak 171, 172
Intensifying Solution, Formula for 135
Intensifying — Strengthening Plate Without Clearing 143
Intensifying Thin Negatives 130
Intensify, Kind of Negatives to 134
Interior Photography, Example of Overcoming Halation in..
Page 145
Interior Photography, Special Pyro Developer for 359
Isochromatic Plates, Cramer 605-623
Judging Plate to be Reduced 273
Judging When Plate is Developed 40-44
Kind of Negatives to Reduce With Persulphate 283, 284
Lantern Slide Plates, Acid Fixing Bath for 803
Lantern Slide Plates, Cramer's 637-639
Lantern Slide Plates, Developer for 426-438, 584, 784
Lantern Slide Plates, Hammer's 846-851
Lantern Slide Plates, Hydroquinone Developer for 791
Lantern Slide Plates, Hydroquinone-Metol Developer for.. 426-434
Lantern Slide Plates, Seed's 705-712
Latitude in Tank Development 486-490
Life of Reducing Solution 272
Life of Developing Solution 527
Light Filters, Cramer's 612, 617
General Index. 383
Light Filters, Hammer's 810
Light Filters, Seed's 713-725
Light for Printing Developing Papers 19
Light, Developing or Ruby 8, 9, 17, 455, 738-741
Light on Dry Plate as Compared to Printing-out Paper, Action
of 192, 193
Light, Nature of Ruby 8, 9, 17
Light to be Used While Intensifying 145
Line Work, Developer for 586
Local Intensifier, When to Apply 177, 178
Local Intensifying 168-178
Locally Intensifying Negatives While Dry 175
Local Reducing 291-306
Local Reducing, Strength of Solution to Use for 295
Local Reducing, Use Running Water to Check 297
" Marine," Study No. 6 Page 119
" Marine," Study No. 10 Page 195
Measure, Conversion from Metric to English (A) Page 365
Measure, Fluid (A) 59, 862
Measure, Metric System of (A) Page 363
Measure, U. S. and English (A) Page 361
Mercury, Dissolving 136
Mercury, Solution Can Be Used Repeatedly Without Renewing 146
Method of Development for Overcoming Halation 365-379
Metol-Adurol Developing Formula 435-438
Metol-Adurol for Negatives and Lantern Slides 435-438
Metol, Factor for Factorial Development With 460
Metol-Hydroquinone, Factor for Factorial Development With 460
"Metol-Hydroquinone Factorial Development 431, 494, 496
Metol-Hydroquinone, Formula for Factorial Developer With.. 470
Metol-Hydroquinone, Formula for Tank Developer With 523
Metol-Hydroquinone, Formulae for 430-434, 580, 682, 779
Metol-Hydroquinone for Negatives and Lantern Slides 426-434
Metol-Poisoning, Antidote for (A) Page 364
Metol-Pyro Developer, Formulae for 582, 684, 781, 783
Metol-Pyro-Tolidol Developer, Formula for 778
Metol-Pyro With Acetone 583
Metric Into English Measure, Conversion of (A) Page 365
Metric Into English Weight, Conversion of (A) Page 365
Metric System of Weights and Measures (A) Page 363
Mixing Factorial Developer Solutions 466
Mixtures, Freezing (A) Page 364
" Morning Lights and Shadows," Study No. 3 Page 61
Negative Envelope 7
Negatives, Crispness and Snap of 37
Negatives, Developing of 2
384 Library of Practical Photography.
Negatives, Drying of 6, 807, Page 32
Negatives, Enlarging 21
Negatives, Fixing of 4
Negatives, Intensifying Thin 130
Negatives of Uncertain Fixing, Formula for Strengthening 148, 149
Negatives, Preserving the 7
Negatives, Reducing 257-290
Negatives, Regulating Color of 50
Negatives, Rinsing After Developing 3
Negatives, Special Developing of White Drapery Portrait. . .380-397
Negatives to Intensify, Kind of 134
Negatives That Can Be Improved By Doctoring, Class of 292
Negatives To Reduce With Persulphate, Kind of 283, 284
Negatives, Washing After Fixing 5
Nitrate of Silver, To Remove Stains of (A) Page 364
Nitric Acid, Nature of 46
Nitric Acid Stains, To Remove (A) Page 364
Non-halation Plates, Cramer's 624-627
Non-halation Plates, Hammer's 859
Non-halation Plates, Seed's 693-695
Non-halation Plates, Seed's Ortho 701
Non-halation Plates, Developer for Tank Development of.. 484-522
Non-staining and Non-poisonous Developer — Hydroquinone-
Eikonogen 413-425
Normal Exposures, Development of 561-566
Obtaining the Factor 450, 467, 471-473
" Ocean Waves," Study No. 14 Page 267
" Old Cedars," Study No. 1 Page 25
Old Developer, Action of 35, 36
Old Developer, Use of 33, 196
Orthochromatic Plates, Hammer 810-819
Orthochromatic Plates, Screens for 612-617, 713, 810
Orthochromatic Plates, Seed's 696-700, 713, 725
Orthochromatic Plates, Seed's Commercial 702
Orthochromatic Plates, Tank Developer for 484-522
Ortol Developer, Formula for 579, 683
Outfit, Developing 12
Overcoming Halation in Interior Photography, Example of. . .
Page 145
Over-developed Plates, Reducing 204, 259
Over-exposed, Treatment of Plate Slightly 209
Over-exposed, Treatment of Plate Which You Know to be . .
207, 208
Over-exposures, Advanced Development of 240-256
Over-exposures Corrected by Proper Development 202, 203
Over-exposures, Developing 187-210
General Index. 385
Over-exposures, Developing Extreme 202, 203
Over-exposures, Developing — Difficulties 211-239
Over-exposures, Example of Page 115
Over-exposures in Commercial Photography 243
Over-exposures, Practice Work 210
Over-exposures in Portrait Work 255
Over-exposures, Use of Hydroquinone for 422-425
Over-timed, Why Plates Are 195
Panchromatic Plates, Seed's 726-732
Persulphate of Ammonia Formula 277
Persulphate of Ammonia, Kind of Negatives to Reduce With
283, 284
Persulphate of Ammonia, Nature of 286
Persulphate of Ammonia Reducer 261, 274
Persulphate of Ammonia Reducer Grows Stronger With Age.. 275
Persulphate of Ammonia, Reducing With 303
Persulphate of Ammonia, Traces of Hypo in 281
Plans of Dark Room Pages 15, 16, 21
Plate Emulsion, Dry Page 9
Plate Holder, Filling the 554
Plates After They Have Dried, Reducing 271, 301, 302
Plates Appearing Yellow After Reducing 269
Plates Are Developed, Judging When 40-44
Plates Becoming Stained While Intensifying 142
Plates Developed Too Far Before Restraining 206
Plates, Developing Different Brands of 198-200
Plates, Developing X-Ray 587, 588
Plates, Double Coated 45
Plates, Double Coated — Cramer's 624-627
Plates, Double Coated — Hammer's 859-861
Plates, Double Coated— Seed's 693-695
Plates Hardened in Alum, Reducing 280
Plates in Dark Room, Changing Box for 20
Plates, Proper Color of 50
Plates, Seed's Panchromatic 726-732
Plates, Seed's Process 704
Plates to be Reduced, Judging 273
Plates Too Quickly, Restraining 205
Plates to Use for Intensifying Experiments 153, 154
Plates to Use for Local Intensifying Experiments 176
Plates With Developer, Flowing the 2
Plates, X-Ray (Cramer's) 630-633
Plates, X-Ray (Hammer's) 825-827
Poisoning, Antidote for Metol (A) Page 364
Poisons and Antidotes, Table of (A) Page S58
Portraiture, Seed Plates for 690, 691
386 Library of Practical Photography.
Portraiture, Over-exposure for 255
Portraiture, Under-timing of 101, 255
Portrait Negatives, Special Development of White Drapery. .380-397
Portrait Photography, Universal Developer for 322-337
Potash in Pyro Developer, Carbonate of 768, 776
Potash, Formula for Reducing With Red Prussiate of 265
Potash, Nature of Red Prussiate of 285
Potash Reducer, Red Prussiate of 260
Potassium Bromide, Nature of 46, 421
Potassium Bromide, Preparing a 10% Solution of 201
Potassium Bromide Solution, Mixing 34
Potassium Bromide, Use of 32
Practical Advice on Exposure 733-737
Practice Work — Developing Under-exposures 119
Practice Work — Factorial Development 476-478
Practice Work — Over-exposures 210
Practice Work— Tank Development 517-522, 529, 530
Preparing a 10% Solution of Potassium Bromide 201
Preparing the Stock Solution for Factorial Developer 463-465
Preservative of Developing Agent 25
Preserving the Negative 7
Preserving the Pyro 60
Printing and Developing Department in Dark Room 19
Process Plates, Seed's 704
Pyro- Acetone Developer, Formula for 577
Pyro-Acetone for X-Ray Plates 588
Pyrocatechin Developing Formula 783
Pyro Developer, Action of 24, 108
Pyro Developer, Carbonate of Potash in 768, 776
Pyro Developer for Commercial Photography 357-379
Pyro Developer, Formula for 47, 578, 678, 767, 777
Pyro, Effect of Page 32
Pyrogallic Acid — Developing Agent Page 10
Pyrogallic Acid, Factor for Factorial Development With 460
Pyrogallic Acid Formula for Tank Developer With 504
Pyrogallic Acid, Nature of 46
Pyro-Metol-Acetone Developer for Tray or Tank 597
Pyro-Metol Developer, Formula for 582, 684, 781, 782
Pyro-Metol-Tolidol Developer, Formula for 778
Pyro-Metol With Acetone 583
Pyro, Preserving the 60
Pyro Stain, To Remove (A) Page 364
Ray Filter for Cramer Iso Plates 612-617
Ray Filter for Hammer Orthochromatic Plates 810
Ray Filter for Seed's Orthochromatic Plates 713-725
Red Prussiate of Potash, Formula for Reducing With 265
II— 3o
General Index. 387
Red Prussiate of Potash, Nature of 285
Red Prussiate of Potash Reducer 260
Reduce Plates or Films, Best Time to 264
Reduced, Judging Plates to be 273, 274
Reducer, Action of 262
Reducer Grows Stronger With Age, Persulphate 275
Reducer, Persulphate of Ammonia 261, 274
Reducer, Red Prussiate of Potash 260
Reducer to Films, Applying the 304-306
Reducer With the Brush, Applying the 296
Reducer With the Finger or Tuft of Cotton, Applying the. .299, 300
Reducing, Avoid Granular Surface by Returning to Hypo Bath
When 298
Reducing, Clearing the Plate or Film After 270
Reducing, Example of Page 115
Reducing, General Negative 257-290
Reducing, Local 291-306
Reducing Over-developed Plates 204, 259
Reducing Over-exposed Plates 204, 259
Reducing Plates After They Are Dry 271, 301, 302
Reducing, Plates Appearing Yellow After 269
Reducing Plates Hardened in Alum 280
Reducing, Strength of Solution to Use for Local 295
Reducing Solution, Life of 272
Reducing Solution, How to Keep 272
Reducing the Plate 268
Reducing, Use Running Water to Check Local 297
Reducing With Persulphate of Ammonia 274, 303
Reducing With Persulphate of Ammonia — Difficulties 317-321
Confining Solution to Only Parts to be Reduced 321
Parts of the Negative Reduced With Persulphate Stained 319
Persulphate of Ammonia Bath Reducing Too Quickly.. 318
Persulphate of Ammonia Not Reducing 317
Plates Very Glossy After Reducing 320
Reducing Too Quickly, Persulphate of Ammonia Bath.. 318
Stained, Parts of the Negative Reduced With Persulphate 319
Reducing With Persulphate of Ammonia, Kind of Negatives
for 283, 284
Reducing With Red Prussiate of Potash, Formula for 265
Reducing With Red Prussiate of Potash— Difficulties 307-316
Negatives Reducing in Clearing Solution 316
Negatives Reducing Too Quickly 308
Negatives Reducing Too Slowly 307
Negatives Stained a Reddish- Yellow After Reducing 311
Negatives Streaked After Reducing 312
Negatives Will Not Reduce 309
388 Library of Practical Photography.
Negatives Yellow After Reducing 313
Puckering After Going Through Clearing Solution, Sur-
face of the Plate 315
Reddish-Yellow After Reducing, Negatives Stained a . . . . 311
Reducing Shadows Too Much 310
Reducing Too Quickly, Negative 308
Reducing, Too Slowly, Negative 307
Removing Yellow Stains from Negative After Reducing.. 314
Streaked After Reducing, Negative 313
Surface of the Plate Puckering After Going Through
Clearing Solution 315
Yellow Negatives After Reducing 313
Yellow Stain From Negative After Reducing, Removing 314
Reducing, Use Discarded Plates for Experimenting With 263
Re-intensifying 139
Residues, Treatment of (A) Page 359
Restraining Development 32
Restraining, Plate Developed Too Far Before 206
Restraining the Plate Too Quickly 205
Restraining the Sensitive Emulsion 194
Retaining Normal Temperature 474, 475
Rocking Tray While Intensifying 141
Rodinol, Factor for Factorial Development With 460
Ruby Light 455, 738-741
Ruby Light, Nature of 8, 9, 17, 455
" Sand Dune," Study No. 11 Page 213
Seed's Plates, Commercial Ortho 702
Seed's Plates, Developing — Difficulties 742-762
Seed's Plates, Developing Formula for 678-686
Seed's Plates for Commercial Photography 696, 701, 703
Seed's Plates for Portraiture and General Work 690, 691
Seed's Plates for Special Commercial and Process Work. . .702-712
Seed's Plates, Instructions by Manufacturer of 642-762
Seed's Plates Lantern Slides 705-712
Seed's Plates, Non-halation 693-695
Seed's Plates, Non-halation Ortho 701
Seed's Plates, Orthochromatic 696-700, 713, 725
Seed's Plates, Panchromatic 726-732
Seed's Plates, Practical Advice on 733-762
Seed's Process Plates 704
Seed's Transparency Plates 505, 506
Seed's Tropical Plates 692
Sensitive Emulsion, Construction of 189-191
Sensitive Emulsion, Restraining 194
" Sheep," Study No. 5 Page 97
Shelving, Dark Room 18
General Index. 389
Silver Stains, To Remove (A) Page 364
Sink, Developing 15
Slow Plates, Hammer's 841-845
Snap and Crispness of Negative 37
" Snow Lights," Study No. 7 Page 137
Soda, Action of Carbonate of 25, 102
Soda, Action of Sulphite of 25
Soda, Nature of Carbonate of 46, 419
Soda, Nature of Caustic 420
Soda, Nature of Hypo-Sulphite of 46, 287
Soda, Nature of Sulphite of 46, 289, 419
Solubilities of Chemicals (A) Pages 348-355
Solution Bottles, Stock 12
Solution, Life of Developing 527
Solution, Use of Bromide of Potassium 34, 201
Special Formula for Strengthening Negatives of Uncertain
Fixing 148, 149
Special Pyro Developing for Commercial Photography 357-379
Special Developing of White Drapery Portrait Negatives. . .380-397
Speed of Cramer Plates 555
Speed of Cramer Plates, Comparative 640
Speed of Developer, Developing With Different Factors Regu-
lates 461
Stains from the Hands, To Remove (A) Page 364
Stand or Tank Developing 484-530
Strength of Solution to Use for Local Reducing 295
Strengthening Plate Without Clearing After Intensifying 143
Stripping Film ^ 86S
Stripping Plates, Cramer's 627-629
Stock Solution Bottles 12
Stock Solution of Carbonate of Soda 47
Stock Solution of Sulphite of Soda 47
Stock Solution for Factorial Developer 460, 461
Studies Illustrating This Volume Were Made, How . . Pages 343-346
Sulphite of Soda, Action of Page 32
Sulphite of Soda, Action in Developer 25
Sulphite of Soda, Nature of 46, 289, 419
Sulphite of Soda Stock Solution 47
Sulphuric Acid, Nature of 46, 290
Symbols, Table of (A) Pages 348-355
Table for Hammer Plates, Exposure 733-737
Table of Factors 460
Table of Poisons and Antidotes (A) Page 358
Tank Developer, Pyro-Metol-Acetone for Tray or 597
Tank Developers for Cramer Plates 596-599
Tank Developing— Difficulties 531-548
390 Library of Practical Photography.
Tank Development With Glycine and Metol-Hydro 523-524
Tank Development With Pyro 107
Tank Development, Directions for Use of 505-508
Tank Development, Formula for 504
Tank Development for< Cramer Plates 590-596
Tank Development, latitude in 486-490
Tank Development, Practice Work for 529-530
Tank Developing Supplement for the Prof. Pages Z24ia-22iq
Tank, Fixing 514
Tank or Stand Developing 484-530
Tanks, Developing 511-513
Tanks, Illustration of Developing Page 211
Tanks, Proportions of Developer for Different Sizes 507
Tanks, Washing 16, 516
Temperature of Developer Page 32
Temperature of Factorial Developer 452-454
Temperature Retaining Normal 474, 475
Ten Minute Factorial Developer, A 468
Theory of Developing 22-25
Theory of Fixing 26
Thiosulphate of Sodium, Nature of 46
" Tokio Water-way, A," Study No. 13 Page 249
Tolidol — Pyro-Metol Developer, Formula for 778
Traces of Hypo in Persulphate Bath 281
Transparency Plates, Cramer's .' 636
Transparency Plates, Developer for 584
Transparency Plates, Hammer's 852-858
Transparency Plates, Seed's 705, 706
Trays for Developing, Use of Two 197
Treatment of a Plate Which You Know Before Developing to
be Under-timed 207, 208
Treatment of a Plate Slightly Over-exposed 209
Treatment of Residues (A) Page 359
Trichromatic Plates, Cramer's 619-623
Tropical Plates, Seed's 692
Twenty Minute Factorial Developer, A 469
Twenty-five Minute Factorial Developer, A 470
Under-exposure 38-44
Under-exposure, Developing 95-118
Under-exposure, Difficulties Developing 120-128
Under-exposure, Developing With Ammonia Developer 439
Under-exposure, Extreme 39
Under-exposure, Use of Eikonogen for 422-425
Under-exposures, Developing — Practice Work 119
Under-exposures, Developing — Normal or Slightly 111-115
Under-timing Portraiture 101
General Index. 391
Universal Developer, Direction for Using 332-337
Universal Developer, Formula for 328-331
Universal Developer, Important Notes on 338-341
Universal Developing 322-341
Universal Developing — Difficulties 342-356
"Up Hill Road, The," Study No. 12 Page 231
Use of Discarded Plates for Experimenting When Reducing. .. 263
Use of Old or Once Used Developer 196
Use of Two Trays for Developing 197
Use Running Water to Check Development in Local Reducing. 297
Ventilation of Dark-room 11
Varnish With Turpentine Before Intensifying, Removing 152
Washing After Developing 799
Washing After Fixing 5, 806
Washing Box 16,516
Washing Box, Illustration of Page 211
"Wave Action," Study No. 9 Page 177
Weights 689, 862
Weights, Apothecaries 59
Weights, Automatic (A) Pages 348-355
Weights, Conversion of Metric to English (A) Page 365
Weights, Fluid 862
Weights, Metric System of (A) Page 363
Weights, Standard English (A) Page 362
Weights, Standard U. S. (A) Page 361
Wet Plate Process 864-941
Wet Plate Process— Acetic Acid Solution 993, 994
Wet Plate Process— Albumenizing the Plate 904, 965
Wet Plate Process — Apparatus Required 875, 876
Wet Plate Process — Application 866-868
Wet Plate Process — Applying the Re-developer 921
Wet Plate Process— Bath, Fixing 898-900
Wet Plate Process— Bath, Fusing the 935, 936
Wet Plate Process— Bath, Testing 894
Wet Plate Process— Bottles 878, 879
Wet Plate Process — Chemicals Required 874
Wet Plate Process — Collodion, Formula for Negative 883
Wet Plate Process— Collodion for Half-tone Work 967
Wet Plate Process — Collodion for Line Work 968
Wet Plate Process — Collodion, Iodizing the 887, 888
Wet Plate Process— Collodion, Negative 881, 882, 937, 938
Wet Plate Process— Collodion, Plain 884-886, 992
Wet Plate Process— Collodionizing or Coating the Plate. .905-908,966
Wet Plate Process — Copper Intensifier 974, 975
Wet Plate Process— Cyanide of Potassium 898, 978-980
392 Library of Practical Photography.
Wet Plate Process— Dark-room 870
Wet Plate Process — Dark-room Equipment 871-873
Wet Plate Process— Developer 895, 972
Wet Plate Process— Developing the Plate 915, 916, 986
Wet Plate Process— Difficulties 942-959
Black Spots, Round 955
Circular Marks on the Plate 957
Comet-Like Spots 954
Contrasty Negatives 956
Fine Net Work Markings Over the Film 947
Fogged Plates 959
Image in the Negative Weak 948
Lines Across Plate After Sensitizing, Straight 949
Negatives Contrasty 956
Part of the Plate Thinner Coated Than Others 946
Parts of the Film Leave the Plate 942
Parts of the Film of the Plate Thicker Than Others 943
Parts of the Plate Apparently Not in Contact 944
Perpendicular Lines, Straight 950
Pin-Holes 953
Plates Fogged 959
Ridges in the Emulsion 945
Round Black Spots 955
Scum on the Film 951, 952
Spots, Comet-Like 954
Straight Lines Across Plate After Sensitizing 949
Straight Perpendicular Lines 950
Streaks in the Developed Plate 958
Weak Image in the Negative 948
Wet Plate Process— Dippers 877
Wet Plate Process— Exposing the Plate 913, 981-985
Wet Plate Process— Fixing Bath 898-900, 973
Wet Plate Process— Fixing the Plate 917
Wet Plate Process — Formula for Developer 896, 897
Wet Plate Process — Formula for Negative Collodion 883
Wet Plate Process — Formula for Negative Varnish 940, 941
Wet Plate Process for the Photo- Engraver 960-994
Wet Plate Process— Fusing the Bath 935, 936
Wet Plate Process— Glass 880
Wet Plate Process— Glass to be Used for Negative, Washing. 901, 902
Wet Plate Process — Intensifier, Copper and Mercury 974-977
Wet Plate Process— Intensifying 922-925, 987, 988
Wet Plate Process— Iodizing the Collodion 887, 888
Wet Plate Process— Iodizing the Silver Bath 892, 893
Wet Plate Process — Keeping the Sensitizing Bath in Work-
ing Condition 931-934
General Index. 393
Wet Plate Process— -Loading the Plate Holder 912
Wet Plate Process — Local Treatment 989, 990
Wet Plate Process — Mercury Intensifier 976, 977
Wet Plate Process— Negative Collodion 881, 882, 937, 938
Wet Plate Process— Origin of 864, 805
Wet Plate Process— Placing the Plate in the Silver Bath. . .909-911
Wet Plate Process— Plain Collodion 884-886, 992
Wet Plate Process — Preparing the Plate to Receive the Col-
lodion 903, 9C4
Wet Plate Process — Re-developing 919
Wet Plate Process— Re-developing Solution, The 920
Wet Plate Process — Reducer, Cyanide 978-980
Wet Plate Process— Rubber Solution 991
Wet Plate Process — Sensitizing Bath in Working Condition,
Keeping the 931-934
Wet Plate Process — Sensitizing Bath, Silver, Preparing
the 889, 890, 969-971
Wet Plate Process— Silver Bath, Iodizing the 892, 893
Wet Plate Process— Silver Bath, Strength of 891
Wet Plate Process— Silver Sensitizing Bath, Preparing the. 889, 890
Wet Plate Process — Special Developer for Negatives 939
Wet Plate Process— Strength of Silver Bath 891
Wet Plate Process— Testing Bath 894
Wet Plate Process — Varnishing 927
Wet Plate Process— Varnishing the Plate 928-930
Wet Plate Process — Washing 926
Wet Plate Process — Washing Glass to Be Used for Nega-
tives 901, 902
Wet Plate Process— Washing the Plate 918
When to Apply the Intensifier Locally 177, 178
White Drapery, Doctoring 293, 294
White Drapery, Example of Development of Page 155
White Drapery, Portrait Negatives, Special Development of. 380-397
Why a Weak Intensifying Solution is Used 171, 172
Why Plates are Over-timed 195
"Woodland Mist," Study No. 2 Page 43
X-Ray Developer, Hammer's 828-830
X-Ray Plates, Cramer's 630-633
X-Ray Plates, Developers for 587
X-Ray Plates, Hammer's 825-827
X-Ray Plates, Pyro-Acetone for 588
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