Photography
Bleach bypass, also known as skip bleach or silver retention, is a modification of traditional film processing through black and white or orthocromatic overlay that is used to achieve muted colors but rich blacks. It generally involves the weakened or partial omission of the bleaching function during the last stage of processing of color film. By doing this, the silver crystals that produce an image in photochemical film stocks are retained in the emulsion alongside the color dyes. This effectively results in a black-and-white image superimposed on the three color separations unified by the final print of color film stock. Film printed in this way usually have reduced saturation and exposure latitude, along with increased contrast and more prominent grain. It usually is used to maximum effect in conjunction with a one-stop underexposure.
History of Zurich.
E. G. Squier.
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