Bleach bypass

Bleach bypass, also known as skip bleach or silver retention, is an optical effect which entails either the partial or complete skipping of the bleaching function during the processing of a color film. By doing this, the silver is retained in the emulsion along with the color dyes. The result is a black and white image over a color image. The images usually have reduced saturation and exposure latitude, along with increased contrast and graininess. It usually is used to maximal effect in conjunction with a one-stop underexposure.

Bleach bypass was first used in Japanese filmmaker Kon Ichikawa's 1960 film Her Brother. Kazuo Miyagawa as Daiei Motion Picture Company's cameraman invented bleach bypass for Ichikawa’s film, inspired by the color rendition in the 1956 release of Moby-Dick, printed using Technicolor, and was achieved through the use of an additional black and white overlay. Despite this early foray into the technique, it remained overlooked for the most part until its use by Roger Deakins in 1984. The effect has subsequently become a regular development tool in labwork, and has remained in widespread usage ever since. Some notable practitioners include cinematographers Rodrigo Prieto, Remi Adefarasin, Darius Khondji, Dariusz Wolski, Oliver Stapleton, Newton Thomas Sigel, Park Gok-ji, Shane Hurlbut, Steven Soderbergh (as "Peter Andrews"), Tom Stern, Vittorio Storaro, and Janusz Kamiński (notably on Steven Spielberg's Saving Private Ryan.