The E-6 process (often abbreviated to E-6) is a chromogenic photographic process for developing Ektachrome, Fujichrome and other color reversal (also called slide or transparency) photographic film.
Unlike some color reversal processes (such as Kodachrome K-14) that produce positive transparencies, E-6 processing can be performed by individual users with the same equipment that is used for processing black and white negative film or C-41 color negative film. The process is highly sensitive to temperature variations: a heated water bath is mandatory to stabilize the temperature at 100.0 °F (37.8 °C) for the first developer and first wash to maintain process tolerances.