Pentax SMC FA 645 400mm f/5.6 ED IF Telephoto Lens
The Pentax 645 400mm f/5.6 ED IF is a 400mm f/5.6 lens designed for Pentax 645 mount cameras. Check GearFocus for current availability, with buyer protection on every purchase.
Pentax SMC FA 645 400mm f/5.6 ED IF Telephoto Lens
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Lens Overview — Pentax 645 400mm f/5.6 ED IF
Key Features — Pentax 645 400mm f/5.6 ED IF
400mm Medium Format Prime: A fixed 400mm focal length designed to cover the larger image circle of the Pentax 645 system, delivering dedicated long telephoto reach with medium format detail.
Pentax 645 Native Mount: Built exclusively for the Pentax 645 system, ensuring direct mechanical and electronic compatibility with Pentax 645-mount cameras.
ED Glass Element: Extra-low dispersion glass reduces chromatic aberration, helping maintain sharpness and color accuracy at long focal lengths.
Internal Focus Design: IF construction means the lens does not change length during focusing, keeping balance consistent and allowing front-mounted filters to stay in position.
Autofocus and Manual Focus: Supports both AF and MF modes, giving photographers the flexibility to switch based on subject type or shooting conditions.
f/5.6 Maximum Aperture: A workable maximum aperture for a medium format telephoto of this focal length, suitable for daylight and well-lit outdoor shooting.
Lens Specifications — Pentax 645 400mm f/5.6 ED IF
| Spec | Detail |
|---|---|
| Use Cases | Wildlife, Birding, Sports, Astrophotography |
| Lens Type | Prime |
| Format | Medium Format |
| Zoom/Prime | Prime |
| Focal Length | 400mm |
| Maximum Aperture | f/5.6 |
| Camera System | Medium Format |
| Lens Mount | Pentax 645 |
| Autofocus | Yes |
| Focus Type | Auto, Manual |
| Image Stabilization | None |
| Filter Thread | 77mm |
Description — Pentax 645 400mm f/5.6 ED IF
The Pentax SMC FA 645 400mm f/5.6 is a dedicated prime telephoto lens engineered for the Pentax 645 medium format camera system. Operating at a fixed 400mm focal length, it is purpose-built for photographers who need serious telephoto reach within a medium format ecosystem. The lens supports both autofocus and manual focus, allowing users to choose the most appropriate mode for their subject matter.
With a maximum aperture of f/5.6, it provides a consistent exposure setting across its single focal length. Note that image stabilization is not included, so a stable shooting platform is important when working at this focal length. The lens accepts 77mm filters, offering broad compatibility with standard filter systems.
At 1.25kg, it is a weighty tool that reflects its medium format build requirements. For Pentax 645 system users who require a fixed long-telephoto prime, this lens offers native mount integration and a straightforward, dedicated focal length for their shooting needs.
Pros — Pentax 645 400mm f/5.6 ED IF
- ✓Native Pentax 645 mount ensures direct, optimized compatibility with Pentax 645-system cameras
- ✓Fixed 400mm focal length prime configuration delivers dedicated long telephoto reach
- ✓Supports both autofocus and manual focus, offering shooting flexibility
Cons — Pentax 645 400mm f/5.6 ED IF
- ✗No image stabilization, requiring careful technique or support at 400mm
- ✗Maximum aperture of f/5.6 limits light gathering at this focal length
- ✗Weight of 1.25kg makes handheld shooting at 400mm physically demanding
Videos — Pentax 645 400mm f/5.6 ED IF
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