Kodachrome

Kodachrome is a brand of color reversal (slide) film and the associated development process released by Eastman Kodak in 1935. Aimed at producing positive color transparencies from color scenes, Kodachrome became one of the most widely used color film stocks of the 20th century. It was praised for its rich, saturated colors, fine grain, and long archival life when stored properly.

Technically, Kodachrome was a multi-layer color film in which color information was captured on three grayscale emulsions. The crucial feature was that the color dyes were not formed in the film during exposure; instead, during processing at Kodak laboratories, separate dye images were created and embedded in the final transparency. The standard processing required a unique multi-step chemical sequence, typically performed only by Kodak-approved labs.

History and impact: Kodachrome was widely used by professional photographers and amateur enthusiasts, becoming a staple for documentary and nature photography. It played a prominent role in the archival record, with many iconic images appearing in magazines and National Geographic. Its characteristic look—bright greens and reds and smooth tonal transitions—became synonymous with mid- and late-20th-century color photography. The film was produced in several speeds and formats, including 35mm slides.

Discontinuation and legacy: Kodak discontinued production of Kodachrome film in 2009 (production stopped) and ended official processing as part of the company's broader move away from chemical film. After a period in which few facilities offered Kodachrome processing, the practice effectively ended in 2010. Kodachrome remains remembered for its distinctive color palette and as a cornerstone of color photography history.

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