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Leica R

Leica R-mount
R-Mount of Leicaflex SL.JPG
A Leicaflex SL female part of in bayonet mount
Type Bayonet
Tabs 3
Flange 47 mm
Connectors Electrical contacts for lens properties on later models

The Leica R bayonet lens mount is the standard method of connecting a lens to the Leica R series of 35 mm single-lens reflex cameras. The mount is descended from those used for the Leicaflex, Leicaflex SL and Leicaflex SL2 SLR cameras, but differs in the cams used to communicate lens aperture information to the camera. 3 cam lenses are compatible with all of the Leica SLR cameras, while R-only lenses have a slightly different mount shape that will not fit on the earlier cameras.

The flange focal distance between mount and film is 47 mm.

On 5 March 2009, Leica announced plans to cease production of its R-Series manual focus SLR and lenses.

The original Leicaflex 1 cam lenses have a single sloped cam that communicates aperture setting to the camera. They can be used on later SL / SL2 and R-series cameras in stop-down metering mode only. Leica do not recommend that 1 cam lenses be used on R8 or R9 cameras because of possible damage to the cameras' ROM contacts. 1 cam lenses may be fitted with later 2 cams, 3 cams, or R cam + ROM contacts (replacing the sloped cams).

2 cam lenses have two sloped cams for the Leicaflex SL and SL2 with TTL metering and are fully compatible with the original Leicaflex. They can be used on R series cameras with the same limitation and warning as 1 cam lenses and may also be fitted with later cams.


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