A rangefinder camera is a camera fitted with a rangefinder, typically a split-image rangefinder: a range-finding focusing mechanism allowing the photographer to measure the subject distance and take photographs that are in sharp focus. Most varieties of rangefinder show two images of the same subject, one of which moves when a calibrated wheel is turned; when the two images coincide and fuse into one, the distance can be read off the wheel. Older, non-coupled rangefinder cameras display the focusing distance and require the photographer to transfer the value to the lens focus ring; cameras without built-in rangefinders could have an external rangefinder fitted into the accessory shoe. Earlier cameras of this type had separate viewfinder and rangefinder windows; later the rangefinder was incorporated into the viewfinder. More modern designs have rangefinders coupled to the focusing mechanism so that the lens is focused correctly when the rangefinder images fuse; compare with the focusing screen in non-autofocus SLRs.
Almost all digital cameras, and most later film cameras, measure distance using electroacoustic or electronic means and focus automatically (autofocus); however, it is not customary to speak of this functionality as a rangefinder.
History
The first rangefinders, sometimes called "telemeters", appeared in the twentieth century; the first rangefinder camera to be marketed was the 3A Kodak Autographic Special of 1916; the rangefinder was coupled. Not itself a rangefinder camera, the Leica I of 1925 had popularized the use of accessory rangefinders. The Leica II and Zeiss Contax I, both of 1932, were great successes as 35 mm rangefinder cameras, while on the Leica Standard, also introduced in 1932, the rangefinder was omitted. The Contax II (1) integrated the rangefinder in the center of the viewfinder.
Rangefinder cameras were common from the 1930s to the 1970s, but the more advanced models lost ground to single-lens reflex (SLR) cameras.
Rangefinder cameras have been made in all sizes and all film formats over the years, from 35 mm through medium format (rollfilm) to large-format press cameras. Until the mid-1950s most were generally fitted to more expensive models of cameras. Folding bellows rollfilm cameras, such as the Balda Super Baldax or Mess Baldix, the Kodak Retina II, IIa, IIc, IIIc, and IIIC cameras and the Hans Porst Hapo 66e (a cheaper version of the Balda Mess Baldix), were often fitted with rangefinders.
The best-known rangefinder cameras take 35 mm film, use focal plane shutters, and have interchangeable lenses. These are Leica screwmount (also known as M39) cameras developed for lens manufacturer Ernst Leitz Wetzlar by Oskar Barnack (which gave rise to very many imitations and derivatives), Contax cameras manufactured for Carl Zeiss Optics by camera subsidiary Zeiss-Ikon and, after Germany's defeat in World War II, produced again and then developed as the Soviet Kiev), Nikon S-series cameras from 1951 to 1962 (with design inspired by the Contax and function by the Leica), and Leica M-series cameras.
The Nikon rangefinder cameras were "discovered" in 1950 by Life magazine photographer David Douglas Duncan, who covered the Korean War. Canon manufactured several models from the 1930s until the 1960s; models from 1946 onwards were more or less compatible with the Leica thread mount. (From late 1951 they were completely compatible; the 7 and 7s had a bayonet mount for the 50 mm f/0.95 lens in addition to the thread mount for other lenses.)
Launched in 1940, The Kodak 35 Rangefinder was the first 35 mm camera made by the Eastman Kodak Company. Other such cameras include the Casca (Steinheil, West Germany, 1948), Detrola 400 (USA, 1940–41), Ektra (Kodak, USA, 1941–8), Foca (OPL, France, 1947–63), Foton (Bell & Howell, USA, 1948), Opema II (Meopta, Czechoslovakia, 1955–60), Perfex (USA, 1938–49), Robot Royal (Robot-Berning, West Germany, 1955–76), and Witness (Ilford, Britain, 1953).
In the United States the dependable and cheap Argus (especially the ubiquitous C-3 "Brick") was far and away the most popular 35 mm rangefinder, with millions sold.
Interchangeable-lens rangefinder cameras with focal-plane shutters are greatly outnumbered by fixed-lens leaf-shutter rangefinder cameras. The most popular design in the 1s were folding designs like the Kodak Retina and the Zeiss Contessa.