Chromogenic prints dominated the second half of the twentieth century and are the standard photo lab–developed snapshots—which can now be printed at home from digital image files—familiar to nearly anyone who has ever owned a camera.

Based on subtractive color principles, chromogenic processing was the result of many years of research and development, by the US-based Eastman Kodak Company and by Agfa, a German company. Both began manufacturing color photographic materials in the late 1930s. Kodak introduced positive (Kodachrome) and negative (Kodacolor) film products that used color-dye-coupler technology for development and printing. Chromogenic film development and printmaking were never intended for use in the hobbyist’s or even professional photographer’s darkroom. Until chromogenic papers became available for digital Type-C prints, practically all chromogenic prints were made in photo labs.

A Kodachrome print is made from a Kodachrome color slide, a direct-positive or positive-to-positive process. The support for the print was originally a thin sheet of acetate but was changed to a fiber paper base in 1961. As mentioned earlier, both the film development and printing processes are complex and, up until 1954, could only be performed at a lab licensed by Kodak. Because of its processing requirements and the widespread transition to digital photography, manufacturing of Kodachrome was discontinued in 2009.