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.
Color Of Ray Filter. The color of the ray filter should be light amber. Using the ray filter you can give a slightly longer exposure, preserving the detail in the foreground, and at the same time securing detail in the shadows.
437. There are many good, inexpensive ray filters on the market, which you can secure from any stockhouse dealing in photo supplies. When ordering a ray filter be sure to give the exact size of your lens barrel.
Development Of Snow Negatives. In making snow negatives one should aim to reproduce the original as truthfully as possible. As snow is white, it will be necessary that the negative be sufficiently dense to retard the rays of light and have the portions which represent snow in the picture only slightly tinted. Do not infer from this that the highlights should be void of detail. The delicate halftones which exist in the snow scene must be reproduced. This, however, is dependent to a certain extent upon the correct judgment of exposure. If too much exposure has been given the delicate half-tones will have been overexposed and unless the amount of over-exposure was known in advance it would be difficult to rectify this in development. It is necessary to secure a fairly strong negative, the highest point of light being quite dense; remembering, of course, not to carry the development so far as to destroy the relative values of the delicate half-tones in the highlights.
439. The formula for the Universal Developer as given in Volume II should be used for this class of work. Be very careful of the temperature, remembering that the best chemical action takes place at 65 degrees Fahr. Never develop plates when they are chilled and cold, as they will develop flat and be even poorer than a greatly over-timed exposure.
440 Printing. - The finished negative must be one that will produce texture of the snow, allowing the shadows to be transparent but not black, heavy masses. Above all, the snow must be luminous snow, and not a dirty, uncertain mass. If you preserve the texture of the snow the whiteness will be soft, but not the hard, blank white so often seen in pictures that are supposed to represent the natural quality of snow.
441. Snow pictures look exceptionally well on platino-type paper, as it renders a rich and realistic effect that is somewhat difficult to obtain on printing-out papers. If you are familiar with the carbon process, unsurpassed results can be secured by printing upon Engraving Black or Blue Black. If bromide enlarging is resorted to, you must be sure to use a developer that will give a rich black without clogging up the shadows, and for this you will find metol an excellent agent.
Practice Work. Should you have an opportunity to photograph snow scenes, apply this instruction and make several negatives, slightly varying the exposure of each and develop one plate at a time, as the first plate developed provides you a key for the developing of the remainder.
443. Make good proof prints from each experiment and place notations on the back of the print covering full information regarding the exposure and development, as well as the manner in which you proceeded to secure the results, and file in your proof file for future guidance.
DEPARTING DAY Study No. 21 - See Page 311 By Geo. H. Scheer, M. D..