2 interactive lens diagrams
Nikon rangefinder mount, 1940s-1960s | 35 mm rangefinder
Nikon S mount belongs to the company's postwar rangefinder system, developed before the Nikon F shifted the brand toward SLRs. The mount is mechanically related in concept to the Contax rangefinder standard, but small dimensional and focusing-coupling differences mean compatibility is not universal outside some wide-angle cases.
S-mount lenses show Nikon's rangefinder-era priorities: bright normals, compact wides, and telephoto lenses designed around coupled rangefinder focusing. These lenses helped establish the Nikkor reputation internationally before Nikon's SLR system became dominant.
They are a useful historical prelude to Nikon F because many optical ideas and focal-length conventions carried forward into the SLR era. At the same time, their short-register rangefinder packaging gives them a very different physical and optical balance from later reflex Nikkors.
Flange focal distance 34.85 mm, hybrid mount. 0° at 12 o'clock from the camera front; the lens-side view is the horizontal mirror. Dotted strokes mark photo-scaled or schematic (not-to-scale) dimensions.