Kodachrome is the brand name for a color reversal film introduced by Eastman Kodak in 1935. It was one of the first successful color materials and was used for both cinematography and still photography. For many years, Kodachrome was widely used for professional color photography, especially for images intended for publication in print media.
Because of its complex processing requirements, the film was initially sold only with the cost of processing; independent photography stores were prohibited from developing Kodachrome. To develop the film, customers had to mail it to Kodak, which would then send the developed film back as part of the purchase price. In 1954, the U.S. Department of Justice found that this practice violated antitrust laws by being uncompetitive. Kodak then entered into a consent decree, requiring the company to offer Kodachrome film for sale without the development fee, as well as license Kodachrome development patents to independent photography stores. Kodak had sold mailers to users who wanted their films to be processed by them. Nonetheless, the process-paid arrangement continued in other markets around the world.