This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
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 photographed, 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 complexion or dark hair. When making the exposure, the white drapery 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 preserve them. You can improve subjects gowned in white drapery, in the lighting, by diffusing the strong lights, but never by under-timing the plate. Usually when the light 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 shadows being fully-timed will give you very soft effects when properly developed. A good way to judge the proper time is as follows: values carefully preserved, but the long exposure necessary is not objectionable for this kind of work.
386. Where you would ordinarily expose four seconds, for this method of developing you should give at least six seconds, 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 developing. 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-
Illustration No. 13 Special Development of White Drapery See Paragraph No. 390.
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 expression and avoid moving of the subjects, a quicker exposure must be made. To accomplish this and retain the same relative color value that a slow plate would give, a faster plate is used, which will be fully exposed with half the time necessary 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 detail 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 developing 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 impossible 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 shadows 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.
391. The principal four points to remember for the successful application of the special development are: -