Table of Contents
Pentax-A 645 SMC 300mm f/4 ED [IF]
Summary
The SMC Pentax-A 645 300mm f/4 ED [IF] is a premium manual-focus telephoto lens for the Pentax 645 medium format system, renowned for its sharpness, build quality, and internal focusing design. Introduced as part of Pentax’s elite A* series, the SMC Pentax-A* 645 300mm f/4 ED [IF] was designed to deliver professional-grade performance for medium format photographers. It features a 300mm focal length, equivalent to approximately 200mm in 35mm terms, making it ideal for wildlife, sports, landscape, and telephoto portraiture. The lens uses an 8-element, 8-group optical formula, including Extra-low Dispersion (ED) glass, which minimizes chromatic aberration and enhances clarity and contrast. The Super Multi-Coating (SMC) further improves flare resistance and color fidelity.
Tech Specs
| Manufacturer | Pentax |
| Series | Pentax-A |
| Model | 645 SMC |
| Focal Length | 300mm |
| Max Aperture | f/4 ED [IF] |
| Min Aperture | f/32 |
| Format | 645 film |
| Image Circle | - |
| Minimum Focus | 300cm |
| Focus Rotation | ° |
| Iris Blades | - |
| Optical Design | 8/8 |
| Squeeze | none |
| Front Diameter | 93mm |
| Filter Thread | 77mm |
| Focus/Zoom Rod | none |
| Native Mount | Pentax 645 |
| Data Protocol | none |
| Length | 208mm |
| Weight | 1360g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | - |
| Iris Drive | - |
| Zoom Drive | - |
History
Country of Origin:
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Service
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Service Manual: (Insert link to manual here)
Full CLA: TBD hrs.
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Cine-Mod
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Focus Ring O.D.: -
Zoom Ring O.D.: -
Iris Ring O.D.: -
De-click Y/N: -
Additional Notes:
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