This section is from the book "Amateur Work Magazine Vol3". Also available from Amazon: Amateur Work.
Printing in damp weather, or any cause that leads to the paper becoming moist will, in the early stages, tend to muddy looking prints, and prolonged printing in dull rainy weather will lead to the image developing out in an imperfect manner during printing. Usually only the shadows blacken while printing in such cases; the halftones will develop out when the print is placed in the developer, but the image will be unsatisfactory. Prints from dense negatives should never be attempted on dull damp days, nor begun so late in the afternoon that the exposure must be carried over to the next morning.
When a number of prints are to be made from one negative, it will be found convenient to develop each print as it is made, but when a number of negatives are being printed from, there may be no time for development till the whole batch is completed. In such a case, each print as it is removed from the printing frame should be placed in the storage tube, where it is safe from moisture and may afterwards be developed at any convenient time. On no account should the prints be placed in a drawer or between the pages of a book, as is commonly and harmlessly done with prints on silver paper. If a piece of paper is too large for a print it should not be torn across, but cut away with a pair of scissors. In tearing it there is always a possibility of particles of the platinum being thrown from the torn part on to the surface of the paper and causing black spots if they remain in situ, or white spots should they be brushed off after printing. The plainotype paper recently brought out by the Kodak Company is free from this defect.
A method of local development with glycerine which gives admirable results in the hands of a worker accustomed to use the brush has been much practised of late years. The iron and platinum salts are not soluble in glycerine, which may be brushed over the surface of the print without injury to it. On the application of the developer, also without a brush, it is to a certain extent diluted with the glycerine in the paper, and development takes place less rapidly than in the ordinary manner, thus giving time for the photographer to watch the growth of the image. Development may be still further delayed by adding a proportion of glycerine to the developer.
The print is exposed in the ordinary way, and having been laid on a sheet of glass, the glycer-ine is brushed well into the paper. It is well to have a finished print side by side with it for reference. Two or three cups containing ordinary developer, developer diluted with glycerine, and plain glycerine are required, together with a supply of camel-hair or sable brushes in various sizes. A brush charged with neat developer is applied to the parts which are to be brought out in full strength and while they are growing in vigor the dilute developer is applied to the surrounding detail which is only required to appear in a light sketchy manner. The edges may be softened or vignetted off by the use of a brush dipped in glycerine. As soon as the desired effect is obtained, the print is immersed in the clearing bath in which the undeveloped parts of the image disappear. The method is one which can only be successfully worked by a person who knows exactly what he wants and who has some training in the use of a brush.
I have said that while the D salts give a bluish black image, that obtained with potassium oxalate tends to give brownish blacks, as does warming the developer in the case of slightly under-exposed prints. The addition of a small quantity of a saturated solution of mercuric chloride to the developer gives tones ranging from a brownish black to a yellowish umber tint. The exact proportion of mercuric chloride to be employed to give certain tints is best found by experiment, the larger the proportions of the mercuric salt the warmer the tone.
When warm tones are required it is, however, more satisfactory to employ the sepia paper. The developer is compounded by adding to each ounce of a solution made by dissolving six ounces of potassium oxalic acid in fifty-four ounces of water, one or two drams of a special solution supplied by the company for the purpose. An alternate developer is made by taking ten parts of the potassium oxalate solution just mentioned and adding one part of a saturated solution of oxalic acid. The developer is to be used at a temperature of 150 or 160 deg. Fahr. An enamelled iron dish is commonly recommended, as it may be placed over a gas ring without fear of breaking. As, however, the enamel quickly cracks, exposing the iron and ruining the developer and prints, it is better to use a granitine dish and to keep it and the solution up to the proper temperature in a water bath or on a sand bath. The manipulation and clearing of the prints are precisely the same as with black paper, but greater care must be taken to preserve the paper from the action of light, and in a general way the process lacks the sweet simplicity of the black paper.
The black paper is sold in three grades; AA, a paper of medium thickness and with a smooth surface ; BB, a smooth, thick paper; and CC, a rough surface, thick paper suitable for large work. It is also supplied in grades known as A, B, and C. These are for the hot bath process, an older type with which we are not at present concerned, and S signifies the sepia paper.
Prints are mounted in exactly the same way as a photograph on other printing papers. Starch paste is best for the purpose, and a gelatine mountant should not be used except with the thick paper. As the paper does not curl up in the same manner as geletino-chlonde and collo-dio-chloride papers, there is no necessity to mount them at all except when they are to be framed. A margin which serves the purpose of the mount in isolating the image from its surroundings is obtained by covering the negative with a mask cut to show just as much of the image as is wanted, and then printing on a sheet of paper just large enough to allow sufficient white round the image. Prints on thick paper, either with rough or smooth surface, so treated are in the best condition for storage in a portfolio, and are more pleasant to handle than when pasted on a heavy mount.
The instructions I have given in detail necessarily occupy a considerable amount of space, but the manipulations are actually most simple. Once the worker has learned to judge when the image is correctly exposed, it is almost impossible for him to go wrong. After a few attempts he will endorse the statement I have made, that the process is at once the simplest and the most economical of all. - Photography.
 
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