Читать книгу Photography in the Studio and in the Field - Edward M. Estabrooke - Страница 23
NEGATIVE COLLODION. C.
Оглавление| Iodide Ammonium | 192 grains |
| Bromide Cadmium | 128 |
| Bromide Potassium | 96 |
| Ether and Alcohol | 32 oz. each |
| Cotton | 320 grains |
The preceding formulæ are for portrait work in studio. For other work, such as outdoor views, p28 landscape or architectural, or for copying engravings, etc., certain modifications of the collodion, to produce greater intensity or more contrast, are desirable. Collodion suitable for such purposes can always be purchased from the photo stock dealer, in quantities desired, and for that reason it is not best for the amateur nor the professional photographer either, to prepare small samples for special purposes. If it should, however, be found at any time necessary to prepare such a collodion, the second formula of Negative Collodion A will be found suitable for views of buildings, copies of engravings and such like work.
It was at first thought to be unnecessary to give a formula for the preparation of pyroxiline or gun cotton, as no individual not in the business can possibly produce an article that can be in any way compared to that made by manufacturers of skill and experience.
For the benefit of any one wishing to experiment, this formula is given:
