N°109455 · Family detail
PentaxTelephoto·PENTAX K mount·1987
Smc Pentax-F* 300mm F/4.5 ED
Specifications01
MountPENTAX K
Focal length300mm
Max aperturef/4.5
TypeTelephoto · Prime
Release year1987
Weight880 g
Filter size67 mm
Min focus distance2 m
Max magnification0.1701
Aperture blades8
Optical elements9
Groups7
AutofocusYes
StabilizationNo
Aperture controlAperture ring (Manual settings + Auto Exposure setting)
Lens hoodBuilt-in telescopic round
TeleconvertersPentax Rear Converter-A 1.4X-S→ 420mm F/6.3
Pentax Rear Converter-A 2X-S→ 600mm F/9
EraFilm era
Production statusDiscontinued
Additional Info02
Lens TypeSuper telephoto prime lens
Summary02
Pentax K-mount 300mm prime telephoto lens with a maximum aperture of f/4.5. Designed for long-distance subjects such as sports, wildlife, and outdoor low-light situations where more reach is needed.
AI-assisted summary — verify against linked sourcesWhere can this lens be adapted?
The Pentax K mount has a flange distance of 45.46 mm. A plain adapter fits a camera whose flange distance is at least 1.46 mm shorter. How lens adapters work
- Pentax DA and FA J lenses have no aperture ring. Use an adapter with its own aperture control.
- Pentax DA lenses are made for APS-C.
- Sony EAdapter · 27.46 mm
- Canon RFAdapter · 25.46 mm
- Nikon ZAdapter · 29.46 mm
- Fujifilm XAdapter · 27.76 mm
- L-MountAdapter · 25.46 mm
- Micro Four ThirdsAdapter · 26.21 mm
- Fujifilm G (GFX)Adapter · 18.76 mm
- Canon EF-MAdapter · 27.46 mm
- Canon EFAdapter · 1.46 mm
A rear element that sticks out can hit the camera mirror.
No plain adapter reaches infinity focus on: Nikon F.

Other Mounts03
No alternate mounts are indexed for this family yet.