Olympus OM system

The Olympus OM System was a line of 35mm single-lens reflex cameras, lenses and accessories sold by Olympus between 1972 and 2002. The range was designed by Yoshihisa Maitani, chief designer for Olympus, and his staff; OM stands for Olympus Maitani.

The nucleus of the system was a series of compact bodies divided into an advanced series and a later consumer-oriented series. The first model was the all-mechanical M-1 which, after pressure from Leica (which already had an M1 model), was renamed OM-1. At the same time the M system was renamed OM System. The camera included a full-aperture TTL Cadmium-sulphide (CdS) exposure meter, and a bayonet lens mount of relatively large diameter. By the end of the 1970s it was joined by the semi-automatic OM-2 and consumer-oriented OM-10. Olympus continued the naming pattern with the 'professional' OM-3 and OM-4, and the consumer-level OM-20, OM-30 and OM-40. The cameras were accompanied by a series of Zuiko-branded lenses, as well as a generous selection of accessories. The majority of OM bodies and lenses were manual-focus only; the OM-707 of 1986 was the only true autofocus model.