grainy photo

Film grain or film granularity is the random optical texture of processed photographic film Film grain develops due to the presence of small particles of a metallic silver, or dye clouds, developed from silver halide that have received enough photons. While film grain is a function of such particles (or dye clouds) it is not a particle but an optical effect. The magnitude of the effect (also known as amount of grain) depends on both the film stock and the definition at which it is observed. It can be objectionably noticeable in an over-enlarged film photograph.

View More On Wikipedia.org