Gel emulsion photography

The processing technology of film is similar to that of ordinary film.

Cinematographic film is a photosensitive material coated with emulsion on a transparent flexible film base, including negative film for cinematography, positive film for printing and reproduction, intermediate film for reproduction and vocal cords for recording. These films are basically the same in structure, and they are composed of two parts: photosensitive silver halide gelatin emulsion layer and supporting film base layer.

classify

1, color photography

There are hundreds of color photography methods in the history of photography, but they can be divided into the following two categories in principle: one is to add the three primary colors of red, green and blue in different proportions to obtain various colors or even white, so it is called additive method. The other is to subtract different proportions of red, green and blue from white light to get different shades of color, even black, so it is called subtractive method.

2. Subtractive film

Color film is made of subtractive color film. The earliest successful subtractive film is the spot color from 1927. Because the replica is made of dye transfer printing, it is also called dye printing. The inventor is Dr. H.T. Calmus.