Chromogenic

 

In a chromogenic process the image is formed by dyes that are produced during development.

During development of the exposed silver halide the developer oxidises, the oxidised developer then reacts with couplers that are incorporated in the emulsion during manufacture. The result of this second reaction is a dye that will absorb certain wavelengths of light depending on the chemical used as the coupler.

The developed silver is then removed by bleaching.