| Manufacturer | Mamiya-Sekor |
| Series | 645 |
| Model | C |
| Focal Length | 150mm |
| Max Aperture | f/4 |
| Min Aperture | f/32 |
| Format | 645 |
| Image Circle | - |
| Minimum Focus | 59 in. |
| Focus Rotation | - |
| Iris Blades | 6 |
| Optical Design | 5 / 4 |
| Squeeze | n/a |
| Front Diameter | n/a |
| Filter Thread | 58mm |
| Focus/Zoom Rod | n/a |
| Native Mount | Mamiya 645 |
| Data Protocol | n/a |
| Length | 3.6 in. |
| Weight | 440g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | Manual |
| Iris Drive | Manual |
| Zoom Drive | n/a |
Country of Origin: Japan
Release Date:
Launch Price:
Design Revisions:
This section restricted to Duclos Staff users.
Service Manual: (Insert link to manual here)
Full CLA: 5-6 hrs.
Enter relevant notes here
Spray and bake threads: +1 hrs.
Enter relevant notes here
Haze / separation in doublets
Do not offer to correct. Cost and risk is too high. Replacing with a donor lens/element is recommended.
PL/EF mount conversion
PL or EF mount conversion is available for most Sekor C primes that are in the original Mamiya 645 mount. Conversion not available for lenses with an integrated shutter system or the Mamiya RZ mount system.
Re-anodize exterior: 6-7 hrs + $50/part (typically 5-7 parts)
some focal lengths may have helical attached to rear housing, if so, additional lapping is required after anodizing. Sekor C lenses have plastic housings. Be careful offering anodizing!
…end of Staff section
This section restricted to Duclos Staff users.
Focus Ring O.D.:
Zoom Ring O.D.:
Iris Ring O.D.: (see notes)
De-click Y/N: Yes
Additional Notes:
Iris gear is possible but not generally recommended since the surface area is very slim and the iris ring on some Sekor C lenses is plastic which can flex.
…end of Staff section