Pentax 645 FA 300mm F/5.6 ED IF Lens
Lens Description
The Pentax 645 FA 300mm F/5.6 ED IF is a medium telephoto prime designed for cameras with a 645 (0.5X) sensor. This prime has a 300mm focal-length. It provides the same field of view as a 150mm lens on a Full-Frame camera.
This prime lens focuses down to 220cm from the imaging plane, capturing subject with a maximum 0.16X magnification. The lens supports autofocus and features a switch to disengage AF for focusing manually. While this lens is capable of AF, it does not have a built-in focus motor. It can only focus with a compatible camera body which features a mechanical AF-coupling.
The lens weighs 775g.
This lens is only available for the Pentax 645 mount. It directly attaches and is fully compatible with all Pentax 645 mount cameras with 645 (0.5X) or smaller sensors.

Focal-Range
Angle-Of-View
Maximum Aperture
Viewing Angle Range
Maximum Aperture
Magnification
Weight
Pentax 645 FA 300mm F/5.6 ED IF Specifications
| Brand | Pentax | Model | 645 FA 300mm F/5.6 ED IF |
|---|---|---|---|
| Mount | Pentax 645 | Max FLM | 0.5X |
| Focal Length | 300mm | View Angle | 10.5° |
| Max Aperture | F/5.6 | Min Aperture | F/45 |
| Min Focus | 220cm | Magnification | 0.16X |
| Filter Size | 67mm | Aperture Blades | 9 |
| Size (D x L) | 75 x 184mm | Weight | 775g |
| Tilt | N / A | Shift | N / A |
| Stabilization | Protection | None | |
| Zoom Drive | Mechanic | Focus Drive | AF with MF Switch |
| Zoom Mechanism | N / A | Focus Mechanism | Internal |
| Hood | Windowed | Focus Motor | External |
| Perspective | Rectilinear | Introduced | 2001-02-11 |
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Pentax 300mm F/5.6 Facts

| 300mm Focal-Length | F/5.6 Constant Aperture |
| 67mm Filter Thread | AF with MF Switch |
| Pentax 645 Mount | 645 (0.5X) Coverage |
| 775g Lens Weight | 75 x 184mm (D x L) |
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