PHOTOGRAPHYA Bromoil Print
FOUR
In the bromoil process, the first step is to make a bromide enlargement. The negative from which a print is to be made is placed in an apparatus resembling the familiar stereopticon and an enlarged image is projected on a piece of bromide paper, or paper that has been coated with an emulsion similar to that used for plates. After the paper has been exposed to the image it is developed, fixed and washed, the result being a large positive print of the original small negative. Often this print is allowed to remain as it is, and it is then known as a bromide enlargement, or, simply, an enlargement; sometimes the worker converts it into a bromoil.
The image in an enlargement consists of metallic silver in a film of gelatine, the gradations of the picture resulting from the varying thicknesses of the silver image. The first step toward changing this to a bromoil is to treat it with certain chemicals that bleach out the silver image and at the same time harden the gelatine in proportion to the amount of silver present. The bleached print is then soaked in warm water, and the high-lights of the picture, where the gelatine is least hardened, absorb the water freely, the half-tones less so, and the shadows least of all. An oily ink, then dabbed on the print with a brush, adheres freely in the shadows, less freely in the half-tones, and least of all in the lights, being repelled by the water in the film. The final result is a print in which the image is formed by varying thickness of ink, which, of course, may be of any color.
The advantages of bromoil over bromide are numerous. In the first place, a bromide print cannot be regarded as absolutely permanent, but a bromoil may be. Next, the color of a bromide print is limited to black and varying shades of brown, unless chemical toning is resorted to, which still further reduces the stability of the image. But a bromoil may be of almost any color, and, indeed, of different colors in different portions of the picture. The greatest advantage of the bromoil process, however, lies in the fact that as much or as little ink as may be desired can be put on any given area. By varying the consistency of the ink it can be made to adhere more or less freely. By modifying the brush action it can be placed on the print or omitted from it, and can even, at times, be removed after being deposited on the paper. It will be seen that the artist has complete control over the gradations, and to some extent, also, over the outlines of the picture. He can therefore make the process respond to his desire for artistic expression to an extent not possible with any other photographic printing medium, even the superficial texture of the image being largely under the worker’s control.
A variant of bromoil is the oil process, though it would be more correct to put it the other way about, the latter process being the older of the two. A sheet of paper is coated with gelatine alone, this being rendered sensitive to light by means of certain chemicals and then printed under a negative. The effect is to render the gelatine hard in proportion to the amount of light-action, that is, hardest in the shadows, less so in the half-tones, and least of all in the lights. The print is then washed to remove the excess of sensitizer, and soaked in warm water; the subsequent operations are the same as in bromoil. Oil is superior to bromoil in being slightly easier to manipulate and in not requiring a dark-room, but it is inferior in that it demands either daylight or a powerful artificial light for printing. Furthermore, a negative the size of the finished print is necessary, whereas with bromoil, large prints can be made from small negatives.
Oil and bromoil have the drawback of not being very rapid to work, three or four 11×14 bromoils representing a good day’s work for a careful manipulator, but they are by far the most satisfactory of all photographic printing mediums when the desire is for artistic expression.
WRITTEN FOR THE MENTOR BY PAUL L. ANDERSONILLUSTRATION FOR THE MENTOR. VOL. 6, No. 12, SERIAL No. 160COPYRIGHT, 1918, BY THE MENTOR ASSOCIATION, INC.
PHOTOGRAPH BY PAUL L. ANDERSONTHE LAKE, WINTER—Nature Photography
PHOTOGRAPH BY PAUL L. ANDERSON
THE LAKE, WINTER—Nature Photography