Friday, 4 November 2011

Notes on Autochrome

Another news article on Verrill’s autochrome process with related photography news of the time.

Notes

From The American Amateur Photographer; Jul 1902; researched by Alan Schenker, digitized by Doug Frizzle, Nov. 2011

Color Photography of the usual mysterious kind is again going the rounds of both the lay and the photographic press. This time the fortunate discoverer is the son of a Yale professor, a fact that may have helped the faith of some that from past experience might have been doubters. But the cat has got so far out of the bag as to warrant us in saying that photography in the colors of nature is not yet. In a communication to The Times-Bulletin the inventor, Mr. A. Hyatt Verrill, tells enough although he says it is a secret process, to show that it is a modification of the three-color method. From it we gather that several negatives are required, got by exposure through color screens and on resensitized plates. These are printed on paper coated with emulsions which, after exposure to light, on development yield the colors of the screens. Here follow his own words. "Several plates (negatives) are required, which are taken through special screens on resensitized plates. The paper is wrought wet, and is coated with emulsions which by the action of light will on development yield the colors of the screens. The various negatives are then printed; the paper developed for each emulsion and finally cleared, the combination of colors in the varying proportions and superimposition reproducing all the colors of the original."

The process appears to be something akin to that introduced in 1896 by Worel, by which he, and more recently Neuhauss and others have met with a passable degree of success. They coat paper with emulsions containing fugitive organic dyes, red-green and blue-violet, each of which is of such a nature as to be completely bleached by white light, but when acted on by colors transmitted or reflected, each color bleaches only its minus two; under red the blue and green disappear, under green the blue and red, and under the blue the green and the red.

Washing Prints.—The Messrs. Lumiere have been experimenting in this direction and, contrary to the generally accepted opinion, running water is not nearly so perfect a method as washing by frequent changes. Briefly, with running water there is an immense waste and the work is neither so soon nor so well done; while seven changes with five minutes between each, although the water does not more than well cover the print, is proved to be perfectly sufficient.

To us this was nothing new, as we have for years washed in a similar way and have never seen a faded print from insufficient washing. Our method, and we can strongly recommend it, is to employ two dishes, generally about 10x8 for 5x7 prints. Into one we place two pints of water and put a dozen prints in one by one, taking care that they are thoroughly separated. Then into the other dish another two pints of water, and, drawing the prints one by one, beginning at the bottom or the one first placed in the dish, let them drip for a short time, and place them in the second dish. The first dish is then emptied and rinsed, and another two pints of water placed in it, and the transfer of the prints repeated. In this way the eight changes consume sixteen pints of water and occupy about forty minutes of time, but the washing is complete, and although the prints so washed may fade, it can never be from insufficient washing.

The Price of Silver surely reached its limit on the down grade a short time ago when it was quoted at 47 cents per troy ounce. Of course that makes no difference in the cost of plates or paper, but it would have counted in the old wet collodion and albumen paper days. It does not seem so long either since we allowed 5/4=$1,28 for each ounce that we recovered from photographers waste, and even then some of them were inclined to grumble, not at the price but because they thought they should have got more from their often carelessly collected stuff.

Speaking of what a little work and a great age may do in enhancing the price of silver, The Amateur Photographer says that at a recent sale fourteen ounces brought $20,500, or about $1,500 per ounce; but it was "A Tudor Cup," and that made a mighty difference.

Photography at the Paris Salon.—It turns out that those who were congratulating photography on admission to the Paris Salon, one of the most exclusive of all the exhibitions, were just a little too previous. It would seem that the New York Herald started the story, but it only said that they were received as exhibits, a very different thing from accepted. While photography has given abundant evidence of its being a means of producing pictures worthy of being classed as works of fine art, the time for its acceptance by the Paris Salon is not yet.

A New Yellow.—Many of the yellows used for screens and dark room lights are so fugitive that a new one and one that is like to be more durable is hailed with pleasure. The following is said to give such a yellow. When a solution of ammonium persulphate is added gradually to a solution ammonium sulphocyanide in an open vessel the result is a fine canary yellow, and that woolen material immersed in the solution readily absorbs the color. The material is in general use in most dark rooms and the experiment should be tried by those who have the time. A suitable permanent yellow would be a desirable addition to our colors.

How to Hold the Hand Camera in a Crowd.—A writer in Photography says the best way to hold the hand camera in a crowded street is to take a place behind the crowd, hold the camera, inverted, at arm's length above the head in which position the image can easily be seen in the finder, and the bulb easily pressed.

Intensification.—Dr. Chesterman, in The British Journal of Photography, finds that negatives whitened by mercury for intensification, if blackened by pyrocatechin gives something like twice the intensity of blackening by sulphate of ammonia. The following formula may be employed:

Pyrocatechin ................................... 10 grains.

Caustic potass .................................. 50 grains.

Water ......................................... 10 ounces.

The solution should be made shortly before use as it does not keep well.

An Early Photograph by Talbot.—At an exhibition of photographs, drawings, etc., held in Lacock, the home of the Talbots, the Rev. Mr. Armstrong showed a copy from a photograph made by the Father of Photography in 1835, four years before Daguerre came into the field. It was of a latticed window in Lacock Abbey, the original being so small as to need a microscope to show the 200 sections of glass, but in the enlargement they showed perfectly.

Cleaning the Silver Bath.—There are some who still work wet collodion and who have from time to time to clear the bath from alcoholic and other impurities by the old, old sunning method. Dr. Vogel recommends, instead of the sunning which needs sunlight and takes considerable time, about five grains of potassium permanganate, and five minims nitric acid to each two pints, and the whole to be gently warmed; saying that in this way what by sunning might take several hours could be done in a few minutes. It is given as something new, but older wet collodion workers will remember that except for the heating, it is almost as old as the sunning. Our note book shows that the permanganate was employed for this purpose as early as 1863.

Sepia Platinotype.—Mr. Inston, whose platinotype prints are admired all over England, gives the following as a new and excellent method for the production of the finest sepia tones. He employs the "C C" paper, prints a shade darker than for black tones, and makes the developer thus:

Neutral oxalate of potass....................... 2 ounces.

Mercuric chloride ............................. 1l/2 drams.

Potass citrate ................................. 2l/2 drams.

Acid citric ..................................... 4 drams.

Place these ingredients in a perfectly clean bottle containing fourteen ounces of water, and within an hour, after all are dissolved the developer will be ready for use. To develop take one part of the developer and one part of water, and slightly warm it in an enameled dish over a gas or other flame. Then pour it back into the measure and with the usual sweep, flow it over the print face up; and keep the dish rocking till development is complete. Then, without washing, place the print at once into the acid fixing solution, but weaker than usually prescribed, say, not stronger than 1 in 200. Follow this up with at least two such baths, or until one is sure that every trace of iron is removed, and wash in the ordinary way.

The color got in this way is said to be finer than by any other, the printing should be carried just far enough, and the negative should be of the right kind, not necessarily strong, but with full detail and suitable contrast.

The Philadelphia Salon.—We regret to learn that it has been definitely decided by the Photographic Society of Philadelphia not to hold this year, what we had fondly hoped was to become an annual treat to the lovers of photography, the Photographic Salon. We are glad, however, to say that we have it on the best possible authority that not only has the Salon idea not been abandoned, but that arrangements for the holding of one next year has already been under consideration; and, although, it is a long time to look forward, we take this opportunity of expressing the wish that it will then be such a success as will strengthen the hands of those who are determined to make the Philadelphia Salon an annual institution.

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As an armed forces brat, we lived in Rockcliff (Ottawa), Namao (Edmonton), Southport (Portage La Prairie), Manitoba, and Dad retired to St. Margaret's Bay, NS.
Working with the Federal Govenment for 25 years, Canadian Hydrographic Service, mostly. Now married to Gail Kelly, with two grown children, Luke and Denyse. Retired to my woodlot at Stillwater Lake, NS, on the rainy days I study the life and work of A. Hyatt Verrill 1871-1954.