In photography, any of a variety of organic compounds which form color images in color photographic films and papers. These compounds are colorless before developing; when a silver halide image is developed following exposure, these compounds mix with by-products of the chemical reactions of the developer and form cyan, magenta, and yellow dyes in proportion to the density of the silver halide developed on the emulsion. Other varieties of color coupling compounds are used in color photographic negatives as masking dyes, a color correction technique. It is these compounds which result in the pinkish or brownish appearance of color negatives.