The Nikon S-mount is a type of interchangeable lens mount used by a series of Nikon 35 mm rangefinder cameras (Nikon I, Nikon M, Nikon S, Nikon S2, Nikon SP, Nikon S3, Nikon S4). The lenses were sold under the name Nikkor. S-mount lenses were produced from 1951 up to 1964.
Technical details The mount was a mechanical copy of the Zeiss Ikon Contax rangefinder mount; however, small differences between the two mean that although Zeiss wide-angle lenses can be used on the Nikon cameras and vice versa, the longer lenses (50 mm and above), if used, will not be able to focus at both close range and infinity. Nikon made a small number of longer focal length lenses specifically designed to focus properly when mounted on a Contax. These were the 85 mm, 105 mm, and 135 mm lenses. Each was marked with a "C" on the side of the lens barrel. This is not to be confused with a "C" mark used as a suffix to the serial number. Some early Nikkors used this mark to denote that the lenses were coated. The mount itself has two bayonets, one inside the camera and another outside. The body has a built-in focusing extension for lenses that use the inside bayonet, so these lenses do not need to have a focusing helicoid built into the lens barrel. As a consequence, the 5 cm f/1.4 lens that was normally sold with the body is extremely small (about the size of a golf ball) since the lens contains only the optics and aperture. Focusing of such lenses could be done by rotating the toothed wheel on the top front of the camera body or by rotating the lens barrel itself (the distance scale is on the camera body). The external bayonet is used to mount longer and heavier lenses where the built-in helicoid would not be strong enough to rotate the lens barrel. Such lenses are focused using a focusing ring and distance scale on the lens just like typical interchangeable lenses; the distance scale on the camera body is covered by the lens flange and thus is not visible when the external bayonet is in use.
Cameras
From 1948 to 1968, Nikon produced eight camera bodies for the S-mount:
Nikon I Nikon M Nikon S Nikon S2 Nikon S3 Nikon SP Nikon S4 Nikon S3M They later produced two commemorative models in the 2000s:
Nikon S3 2000 Nikon SP Limited Edition
Lenses Nikon produced a large range of Nikkor-branded lenses for these cameras with focal lengths ranging from 21 mm to 1000 mm. Several other manufacturers, including Fuji (now Fujifilm), Komura and Zunow, made S-mount lenses at the time, of which the Zunow 5 cm f/1.1 lens is a keenly sought-after collector's item. In 2002, Cosina Voigtländer manufactured a camera with an S-mount, the Bessa R2S, as well as several lenses for the Nikon S-mount. In general, wide-angle Nikkor lenses with S-mount will mount directly to Contax bodies. 85 mm to 135 mm lenses were sold with special Contax mounts. In addition, most of the lenses were available as optically identical versions with an M39 lens mount. The 135 mm f/3.5 lens was additionally available in a version with a Kine Exakta mount.
Further reading Rotoloni, Robert (1983). Nikon Rangefinder Camera (Second ed.). Hove, East Sussex: Hove Foto Books. ISBN 0-906447-25-9.
Notes
See also Nikkor Nikon F-mount Nikon Z-mount Nikon 1-mount
References
External links W-NIKKOR 3.5 cm f/1.8 "NIKKOR Club Quarterly" article about the design of about what was at the time the fastest wide-angle lens in the world. Stephen Gandy's site Brief descriptions of Nikon S-mount cameras and Nikkor/Voigtlander lenses in S-mount.
