Mamiya Mamiya-Sekor C 90mm f/3.8
Introduced: 1974
Mamiya Sekor C 90mm f/3.8 is the wide-normal lens for the Mamiya RB67 system — equivalent to roughly a 45mm field of view in 35mm terms (6×7 normal is ~95mm; this lens sits on the wide side of normal). Often the kit lens shipped with new RB67 bodies.
Key features
- Mamiya RB bayonet — fits all RB67 bodies (Pro, Pro-S, Pro-SD)
- Built-in Seiko leaf shutter — 1s to 1/400, X-sync at all speeds
- 77mm filter thread
- 5-element/4-group optical formula with single coating (older C series)
- Close-focus with body bellows extension — no extension tubes needed for ~1:3 magnification
- Manual aperture + manual focus — fully mechanical operation
Use case + rendering
The 90mm is the environmental-portrait + landscape standard for RB67 — short enough to capture surroundings, long enough to flatter facial proportions. Sharp wide open by 1980s standards, sharper by f/8. Mamiya Sekor C lenses are known for good resolution but slightly cool color rendering compared to Zeiss Hasselblad equivalents.
On the RZ67 (with Z-RB adapter), this lens works in stop-down meter mode only.
Compatible bodies
- Mamiya RB67 Pro-S
- Mamiya RB67 Pro-SD (later RB body, accepts both C and KL lenses)
- Mamiya RZ67 Pro II — via Z-RB adapter, stop-down metering
Related lenses
- Mamiya Sekor C 127mm f/3.8 RB — true normal
- Mamiya Sekor C 180mm f/4.5 RB — portrait telephoto
- Mamiya Sekor Z 110mm f/2.8 RZ — RZ-mount sibling