Pentax 300mm f/6.3 Tele-Takumar M42 Lens
The Pentax 300mm f/6.3 is a 300mm f/6.3 lens designed for M42 Screw Mount mount cameras. Check GearFocus for current availability, with buyer protection on every purchase.

Pentax 300mm f/6.3 Tele-Takumar M42 Lens
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Lens Overview — Pentax 300mm f/6.3
Key Features — Pentax 300mm f/6.3
300mm Prime Telephoto: Fixed 300mm focal length delivers a dedicated long-range perspective well suited to wildlife, sports, and distant subjects.
M42 Screw Mount: Universal screw mount that adapts easily to most modern mirrorless and DSLR systems with widely available, inexpensive adapters.
Full Frame Coverage: Image circle covers full frame sensors without vignetting, making it usable on both crop and full frame bodies.
Manual Focus Only: Smooth manual focus ring offers a tactile, deliberate shooting experience typical of vintage Takumar glass.
f/6.3 Maximum Aperture: Modest maximum aperture keeps the lens compact and lightweight, though a tripod or stable support is recommended in lower light.
58mm Filter Thread: Standard 58mm front thread size makes compatible ND, polarising, and UV filters easy to source and affordable.
Lens Specifications — Pentax 300mm f/6.3
| Spec | Detail |
|---|---|
| Use Cases | Wildlife, Birding, Sports |
| Lens Type | Telephoto |
| Format | Full Frame |
| Zoom/Prime | Prime |
| Focal Length | 300mm |
| Maximum Aperture | f/6.3 |
| Camera System | DSLR |
| Lens Mount | M42 Screw Mount |
| Autofocus | No |
| Focus Type | Manual |
| Image Stabilization | None |
| Filter Thread | 58mm |
Description — Pentax 300mm f/6.3
The Pentax 300mm f/6.3 Tele-Takumar is a prime telephoto lens built around the M42 screw mount system. It offers a fixed 300mm focal length with full frame coverage, making it suitable for use on full frame sensors without cropping concerns. The maximum aperture of f/6.3 is on the narrower side, so photographers should plan accordingly when it comes to light-gathering in dim conditions.
Focusing is entirely manual, with no autofocus capability — a characteristic that defines the vintage shooting experience this lens delivers. There is no image stabilization, so a steady hand or tripod support is advisable at this focal length. The lens weighs 640g and accepts 58mm screw-in filters, making accessory use straightforward.
Whether used on an original M42-mount body or adapted to a modern mirrorless or DSLR system, this Tele-Takumar represents a piece of classic Pentax optical heritage for those who appreciate manual glass.
Pros — Pentax 300mm f/6.3
- ✓Full frame coverage ensures no vignetting on larger sensors (lensFormat: Full Frame)
- ✓Fixed 300mm focal length provides a dedicated telephoto perspective (minFocalLength/maxFocalLength: 300)
- ✓Relatively lightweight at 640g for a 300mm telephoto lens (weight: 640g)
Cons — Pentax 300mm f/6.3
- ✗Maximum aperture of f/6.3 is narrow, limiting performance in lower light conditions (maximumAperture: 6.3)
- ✗Manual focus only — no autofocus support (autoFocus: false)
- ✗No image stabilization, which demands careful technique at 300mm (imageStabilization: None)
Videos — Pentax 300mm f/6.3
Pentax prime lenses - a guide to great vintage and modern lenses, from Takumar to today's D FAs — Simon's utak









