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Practical Color Photography | by E. J. Wall



In this little work historical and theoretical data have been as far as possible omitted. My endeavor has been to supply an elementary practical manual of the various processes of Color Photography, and no method or formula has been given that has not been personally tested in practice. This has naturally limited the scope of the work to some extent, but it has not entailed the omission of any information of practical value.

TitlePractical Color Photography
AuthorE. J. Wall, F.C.S., F.R.P.S.
PublisherAmerican Photographic Publishing Co.
Year1922
Copyright1922, American Photographic Publishing Co.
AmazonPractical Color Photography
-Chapter I. The Spectrum - Color Formation
BEFORE considering the various processes of color photography, it is essential to explain the formation of color, and the difference between the additive and sub-tractive methods of color reproduction...
-The Spectrum - Color Formation. Part 2
We may, therefore, say that there are three fundamental or primary colors in the spectrum, by the admixture of which we can form all intermediate colors and white. The positions of these fundamental c...
-Chapter II. The Sensitive Plates
EVERY photographer knows that the ordinary plate is practically color-blind, that is to say, it reproduces the violets and blues more or less like white, and the greens, yellows and reds more or less ...
-The Sensitive Plates. Part 2
Many dyes have been suggested for panchromatizing and more formulas for sensitizing, but as simplicity and ease of attaining results are among the main features that have been kept in view throughout ...
-The Sensitive Plates. Part 3
This is not the cheapest method of working, but the author has proved it in practice to be one of the most reliable, and when one considers that the actual cost of the dye and drying alcohol is approx...
-Chapter III. Color Filters
TO explain the action of tri-color filters it is necessary to recall the statement that all colors can be formed from three fundamental colors. But while we have seen that these three fundamental colo...
-Color Filters. Part 2
For this reason also, it is important that the final filter glass be flat, and this is one of the difficulties in making filters, that is, to obtain six pieces of glass that are sufficiently flat to b...
-Color Filters. Part 3
When the glasses are dry they should be carefully polished with a clean rag. These glasses are used for the first coating and the dried dyed film has to be stripped from them, but unless they are perf...
-Color Filters. Part 4
They really require a warm place and should be left three weeks in a flat position, so that as soon as the first lot of exuded balsam has been wiped off they should be placed flat on a glass or shelf ...
-Color Filters. Part 5
Special sliding backs can be obtained commercially, fitted with the three filters and made to take three plate-holders, or with some plate-holders, particularly of the English book-form pattern, the f...
-Chapter IV. The Darkroom
AS the plates used for color photography are sensitive to all colors, it is obvious that we cannot use the normal red light for illumination of the dark room, and if this were reduced, as it can be, s...
-The Darkroom. Part 2
One further advantage of this process is that it actually reduces the chemical fog on the negative, which is a very great assistance in practical work; for thus, in common parlance, it enables us to o...
-Chapter V. The Camera And Exposure
UNFORTUNATELY there is no reasonably priced three-color camera on the market. So, unless one is prepared to make a camera, the only alternative is a sliding back, and this limits the work in the main ...
-The Camera And Exposure. Continued
The adjustment of the filter absorptions is rather a delicate matter; but a suitable filter for A can be made from rose Bengal 0.8 g per square meter, or phenosafra-nin 0.48 g, or a Wratten & Wainwrig...
-Chapter VI. Subtractive Processes. Superimposed Carbon Prints
PROBABLY everyone knows the fundamental basis of the carbon process, a name that has clung since its first inception, although carbon is no longer the pigment used. Briefly, some water-insoluble pigme...
-Subtractive Processes. Superimposed Carbon Prints. Part 2
Even more convenient than this is a paper actinometer of the so-called terrace pattern. To make this, procure a strip of glass; a bit of an old negative answers admirably. This should be one inch wide...
-Subtractive Processes. Superimposed Carbon Prints. Part 3
The developer is nothing but hot water, and it is preferable to work at as low a temperature as possible. A dish should be filled with water at 380 C. (100 F.), and it is advisable to have a kett...
-Subtractive Processes. Superimposed Carbon Prints. Part 4
Another process, which while actually a carbon process, employs no light for the insolubilization of the gelatin, relying upon the action of finely divided silver on the bichromates, which causes inso...
-Chapter VII. The Imbibition Process
THIS process is the transfer of a dye image to a gelatine film; as the result, prints are formed consisting only of transparent aniline dyes in a single layer of gelatine. The finished pictures are ve...
-The Imbibition Process. Continued
The dyes that should be used for this process are natural carmine or lanafuchsin BB or SL for the red impression, indulin blue for the blue, and acid yellow, mikado yellow, or quinoline yellow for the...
-Chapter VIII. Relief Processes
HOWARD FARMER discovered that if a silver image imbedded in gelatine was immersed in a solution of a bichromate a reaction took place and the bichromate was reduced, so that the gelatine surrounding e...
-The Etching Process
Another process, which is quite as simple as that already described, and which is actually simpler if the original negatives are used as the printing matrices, is the so-called etching process. In thi...
-Developed Relief Process
This is another inverse process, that is, one in which a positive is used for the print-plate, which must be exposed through the back. The directions already given for the bichromate relief process al...
-Chapter IX. Mordanting And Toning Processes
IN the processes now to be described the silver image is converted into some salt which exerts an absorptive action on basic dyes. There is no relief formation and the dyed image is imbedded in the or...
-The Copper Mordanting Process
This is somewhat easier to work than the iodide process, as there is less chance of the dyes bleeding; but it is more particularly suitable for the red and yellow constituent pictures, though it can b...
-The Chemical Toning Processes
These are given rather with the idea of making the subject complete than for their practical value, as in nearly all cases the images are too opaque to be of any value. The iron toning process, howeve...
-The Combination Of Processes
We have dealt so far with the various processes as totally distinct, but it will frequently be found that a combination of one or more of these processes will give excellent results. For instance, sup...
-The Combination Of Processes. Continued
It is advisable to treat all three plates in this way simultaneously, so that there may be no delay in the final transfer. For the final support gelatinized paper is required, which has already been d...
-Chapter X. The Three-Color Gum-Bichromate Process
THIS is essentially a carbon process, and is usually known as the bi-gum process. It is purposely described separately, as it is impossible to obtain the paper commercially and one has to prepare it...
-The Three-Color Gum-Bichromate Process. Continued
Ammonium bichromate 3 g. Citric acid 2 g. Water 25 ccm. If the sensitizer is to be applied afterwards, this latter solution may be omitted, and it will then be possible to prepare quite a stock of ...
-Chapter XI. Three-Color Lantern Slides
HAVING obtained a set of tri-color negatives it is obvious that one can as readily make lantern slides or transparencies as prints, and almost all the processes described for the latter are applicable...
-Three-Color Lantern Slides. Continued
Any of the relief processes already described for prints may be used here, and for this work the best film to use is motion picture positive film, which can be usually obtained to order. This is on ce...
-The Photochromoscope
Instead of using superposed subtractive pictures it is possible to make use of the additive superposition of the pictures, by means of an instrument called the photochromoscope or chromoscope. Then, ...
-The Photochromoscope. Continued
It is advisable to make up stock solutions of the dyes and add these to plain gelatine solution. The stock solution for the blue filter is made from: Crystal violet 3 g. Methylene blue 1 g. Glacial...
-Chapter XII. Screen-Plates
THE fundamental idea of the screen-plate was conceived by Ducos du Hauron in 1867. It belongs to the additive processes, and the principle is similar to a particular school of painting, in which small...
-Screen-Plates. Part 2
There are two distinct methods of using this process. If the screen elements are of a regular geometrical pattern, regularly recurring, then one may use the screen-plate pressed into contact with a se...
-Screen-Plates. Part 3
While directions have been given for making a filter, it must be understood that this is for the autochrome plate. While it can be used for the Paget plate, the makers of this issue special filters an...
-Screen-Plates. Part 4
Development The desensitizing of color plates has been dealt with elsewhere and the same process may be utilized for all screen-plate work. With the separate method, the saf-ranin dyes may be used; b...
-Screen-Plates. Part 5
After the reversing solution has done its work, the plate should be washed for a minute or two, the easiest way being to fill the dish with water, rock gently, throw away the water and refill, and rep...
-Screen-Plates. Part 6
Varnishing The Plate Many operators omit this operation altogether, but it can be recommended, for not only does it give good protection to the tender film but it also increases the transparency of t...
-Screen-Plates. Part 7
Ill-defined patches of greater density than that of the picture as a whole point to dirt on the glass, which, by preventing access of light to the glass, causes less density in the primary image and c...
-Screen-Plates. Part 8
Another important point in the projection or viewing of screen-plates is that the color elements are adjusted to give the best results for a mean daylight, and the color rendering is not correct for a...
-Screen-Plates. Part 9
Fig. 20. The required length of magnesium ribbon is cut off, and this will naturally depend on the density of the picture; with ribbon of 2.6 mm width, which is about the average, from 10 to 20 cm ...
-Screen-Plates. Part 10
In the reproduction of a screen-plate it is clear that we might place it with the film in contact with the sensitive plate. Then we should have the color elements reproduced quite sharp, and every neg...
-Stereoscopic Work With Screen-Plates
The combination of stereoscopy and color would seem almost ideal, and should present no particular difficulties to the expert worker in stereoscopy. But there are one or two points that it may be as w...
-Chapter XIII. The Bleach-Out Process
AS a laboratory experiment this is an extremely interesting process, but from the practical point of view it is not worth wasting an hour over, in the present state of our knowledge. It was originally...
-The Bleach-Out Process. Continued
If it is considered preferable to use the ordinary peroxide solution, then this must be used instead of water to make the gelatine solution, and the temperature must be kept as low as possible in melt...
-Chapter XIV. The Lippmann Process Or Interference Heliochromy
THIS is probably the most beautiful of all color processes from a theoretical standpoint and yet is also that which has been the least practised, mainly because one has to prepare the plates, exposure...
-The Lippmann Process Or Interference Heliochromy. Part 2
The albumen is the white of eggs, and if the operator is not accustomed to separating the whites from the yolks, it is as well to break each egg separately into a cup and then strain off the white int...
-The Lippmann Process Or Interference Heliochromy. Part 3
All the original formulas for color-sensitizing called for the old cyanin, but much better results can be obtained with the newer isocyanins, and pinachrom is very satisfactory. For the bath method us...
-The Lippmann Process Or Interference Heliochromy. Part 4
An alternative process and one which has much to recommend it, is development with the following hydro-chinon developer: Hydrochinon 3 g. Sodium sulphite, dry 7.5 g Potassium carbonate 2 g. Potassi...
-Chapter XV. The Seebeck Process Or Photography With Silver Subchloride
THIS is another interesting laboratory process of no practical value as, so far, no means of fixing the images has been discovered. It is named after J. T. See-beck, who, prior to 1810, sent to the po...
-Chapter XVI. The Diffraction Process
THIS process was invented by Professor R. W. Wood, of Johns Hopkins University, and is a beautiful application of the phenomena of diffraction by gratings. It is, however, merely a laboratory process,...
-The Diffraction Process. Continued
To obtain even illumination of the positives, a condenser is essential, and it is obvious that a projection lantern will considerably facilitate matters. One of the gratings is placed in contact with ...
-Chapter XVII. The Prismatic Dispersion Process
THIS process was first suggested by Chas. Cros in 1869. He proposed to split up the light by means of a prism, which was to be turned so as to direct the three colored rays to slightly different posit...
-The Prismatic Dispersion Process. Continued
It would be necessary to use a compensating filter, as in all screen-plate processes, to reduce the vision of the plate to that of the eye, and this could only be done by trial and error, using a whit...
-Chapter XVIII. Two-Color Processes, Bi-Packs And Tri-Packs
THE possibility of using two instead of three colors was pointed out by Ducos du Hauron in 1895, and he suggested that red and blue were quite sufficient to produce a color result, provided that too b...
-Two-Color Processes, Bi-Packs And Tri-Packs. Part 2
Erythrosin 0.1 g. Tartrazin 1.0 g. Distilled water 1000 ccm. Bathe three minutes and dry without washing, although the plate should be just rinsed. Instead of tartrazin, naphthol yellow may be used...
-Two-Color Processes, Bi-Packs And Tri-Packs. Part 3
If the positives are to be made by the iodide or mordanting process, it can be easily reversed, if necessary, in the stripping process. If the dialyte or semi-dialyte systems be adopted, the printing...
-Chapter XIX. Cinematography In Colors
THE combination of the illusion of movement given by the motion picture with colors has been for many years the hope of numerous inventors. But a brief sketch of their work can be given, as it would r...
-Cinematography In Colors. Continued
The Smith system was based on the fact that in tricolor projection, the blue-violet constituent adds but little color as such. It brightens up the other colors and forms white. It does provide the pur...
-Conversion Of Weights And Measures
The following tables are sufficient to enable anyone to readily convert the metric into the customary units, and are based on those published by the U. S. Bureau of Standards. Lengths Inches ...
-Bibliography
On the theory of color and color vision generally, the following works should be consulted: Color Measurement and Mixture. W. Abney. London. 1891. Textbook of Color. O. N. Rood. New York. 1913. Col...









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previous page: Photography | by Henry P. Maskell
  
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next page: Uncle Alberts Manual Of Practical Photography And Guide To The Reproductive Processes | By Powell Perry