Pentax's compact medium format lens — 45mm f/4 for the Pentax 645 or 67 system.
The SMC Pentax-67 45mm f/4 was released in 1989 as the ultra-wide prime for the Pentax 6×7 medium-format system, providing approximately 24mm full-frame equivalent coverage on 6×7 film. Nine elements in 8 groups. Eight aperture blades. 82mm filter (Pentax bayonet filter mount). At 486g. Approximately 37cm MFD.
Nine elements in 8 groups. Eight aperture blades. 82mm filter via Pentax bayonet filter mount (not standard screw-in thread). At 486g the lens is moderate for a medium-format ultra-wide prime. Minimum focus distance of approximately 37cm. Manual focus. Pentax 67 (6×7) medium-format mount. Approximately 24mm full-frame equivalent on 6×7 film.
The 45mm on 6×7 provides approximately 24mm full-frame equivalent — an ultra-wide perspective for the Pentax 6×7 system. The 6×7 format's large film area (56×70mm) requires a large image circle: the 82mm Pentax bayonet filter system accommodates the front element diameter. The SMC (Super Multi Coated) designation indicates Pentax's multi-layer anti-reflective coating.
On the used market the SMC Pentax-67 45mm f/4 is available at Pentax 6×7 ultra-wide prime pricing. Condition checks: aperture blade condition, focus helicoid smoothness, front element for marks. Note: 82mm Pentax bayonet filter mount (not standard screw thread). Compatible with Pentax 6×7 and 67 mount bodies.