Sigma SA-mount
The Sigma SA-mount is a lens mount designed by the Sigma Corporation of Japan for use on their single-lens reflex cameras. The (inner) SA mount uses a bayonet mount which is physically similar to the Pentax K-mount[1] but uses a flange focal distance of 44.00 mm, identical to that of the Canon EF-lens mount. For some while, the SA-mount was extended to also feature an outer bayonet mount, a feature later dropped again, so that only two camera models support it (SD9/SD10).
The mount uses electrical communication between body and lens, like the EF-mount, and in fact uses the same signalling lines and protocol as the EF-mount, despite the physical incompatibility. Sigma has long produced EF-mount lenses for Canon cameras, and thus had the ability to use this protocol.
All Sigma SLRs and DSLRs can use manual focus lenses too, which have no electrical communication between body and lens.
Compatibility
Pentax K-mount (PK) lenses can be fitted straight onto the SA-mount, once the protruding AA lever and AA protector outcrop are removed, though the fit is slightly loose as the SA-mount has a slightly bigger bore than the PK-mount.
Utilizing the SD9/SD10's outer bayonet mount, Nikon F-mount can be fitted and used via a JTAT mount adapter utilizing the SA outer bayonet mount developed by Kazuo Suzuki, Tachibana Seisakusho.[2]
For as long as they don't hit the dust filter in digital cameras, M42-mount lenses can be mounted via adapters utilizing the SA inner bayonet.
Adaptation of lenses for other bayonet mounts on Sigma cameras
Some Sigma DSLR users have become adept at converting high quality manual focus lenses to fit the SA-mount. One such user[who?] in the UK has successfully converted Nikon, Contax Carl Zeiss, Minolta MD, Canon FL and FD lenses to fit the SA-mount. Others[who?] have even produced replacement mounting plates for Sigma DSLRs, which convert them to either Nikon or Leica R-mount, or replaced the mount entirely with an EF-mount.[citation needed]
Camera bodies
| Body | Release date | Sensor |
|---|---|---|
| Film (36 x 24 mm) | ||
| SA-300/SA-300 QD | 1992 or 1993 | N/A |
| SA-300N/SA-300N QD | 1994 | N/A |
| SA-5/SA-5 QD | 1997 | N/A |
| SA-7/SA-7 QD | 2001 | N/A |
| SA-9/SA-9 QD | 2001 | N/A |
| SA-7N/SA-7N QD | 2002 | N/A |
| Digital (20.7 x 13.8 mm) | ||
| SD9 | 2002-10 | Foveon X3, 2268 x 1512 pixels |
| SD10 | 2003-12 | Foveon X3, 2268 x 1512 pixels |
| SD14 | 2007-03 | Foveon X3, 2640 x 1760 pixels |
| SD15 | 2010-06 | Foveon X3, 2640 x 1760 pixels |
| Digital (24 x 16 mm) | ||
| SD1 | 2011-05 | Foveon X3, 4800 x 3200 pixels |
| SD1 Merrill | 2012-02 | Foveon X3, 4800 x 3200 pixels |
There were two non-SA-mount precursors to the SA-300, the Sigma Mark-1 (1976) with M42 screw lens mount, and the Sigma SA-1 (1983) with Pentax K-mount.
Lenses
All SLR lenses manufactured by Sigma since 1993 are available for the SA-mount. A partial listing can be found here.
References
- ^ Stephen H. Westin. "Comparison: Sigma SA mount vs. Pentax K".
- ^ http://www.jtat.com/sd/sd_main/SD_Nikon.html