Pentax will celebrate the K-Mount 50th anniversary on December 21 – check the dedicated pages in the US, Japan, and Europe for the details (you can share a photo taken with any K-mount camera, along with the story behind it):
Brief history of the Pentax K-mount (1975 – present):
| Year | Milestone | Key Features / Changes |
|---|---|---|
| 1975 | K-mount launched | Bayonet mount replaces M42 screw mount. Introduced with K-series film SLRs (K2, KM, KX). Open aperture metering, mechanical aperture linkage. |
| 1976 | K-series expands | K1000 becomes the legendary student/camera-club classic (produced until 1997). |
| 1981 | KA-mount (K-mount with contacts) | Added electrical contacts for aperture info. Enabled Program & Shutter-priority AE (ME-F, Super Program/Program A). Backward compatible. |
| 1983 | KAF-mount | Added autofocus drive shaft in body (first AF SLR: ME-F in 1981 used body-driven AF, but KAF standardized it). Used in SF series. |
| 1987 | KAF2-mount | Added power-zoom contacts (for early power-zoom lenses). Used in Z/PZ series. |
| 1991 | “Crippled” KF mount | Cheaper bodies (e.g., Z-50p) lost mechanical aperture feeler; could only use KA or newer lenses properly. |
| 1997 | FA lenses & digital prep | FA lenses add data contacts for distance info (used later for shake reduction). |
| 2003 | *ist D – first Pentax digital SLR | Same K-mount, full backward compatibility with manual lenses. |
| 2006 | KAF2 → KAF3 | Removed mechanical aperture lever on some lenses (electronic aperture only). First KAF3 lens: DA* 16-50mm f/2.8. |
| 2012 | K-01 mirrorless | Uses K-mount natively on a mirrorless body (designed by Marc Newson). |
| 2013 | K-3 introduces KAF4 | Support for electromagnetically controlled aperture (no mechanical lever needed). Required firmware update on older bodies. |
| 2016 | Pentax K-1 full-frame DSLR | First full-frame digital Pentax since film era; still uses K-mount (42+ years old at this point). |
| 2020 | K-3 Mark III & KF | Flagship APS-C DSLR; new KF entry model. K-mount continues unchanged. |
| 2025 | 50th anniversary | K-mount turns 50 years old (June 1, 1975–2025). Still in active production and fully backward compatible with 1975 lenses on modern bodies. |
Black Friday deal: Pentax 17 and Pentax Spotmatic SP film 1:1 wooden replica cameras now 50% off
