N°109557 · Family detail
PentaxCinema·PENTAX K mount·1975
Pentax SMC 300mm F/4
Specifications01
MountPENTAX K
Focal length300mm
Max aperturef/4
TypeCinema · Telephoto · Prime
Release year1975
Weight1020 g
Filter size77 mm
Physical length188 mm
Min focus distance4 m
Aperture blades8
Optical elements7
Groups5
Min aperturef/32
AutofocusNo
StabilizationNo
Aperture controlAperture ring (Manual settings only)
Lens hoodBuilt-in telescopic round
TeleconvertersPentax Rear Converter K T6-2X→ 600mm F/8
EraFilm era
Production statusDiscontinued
Additional Info02
ModelSMC
FormatFull-Frame
SeriesK Series Prime
Squeezenone
Lens TypeSuper telephoto prime lens
Iris Blades8
Release Date1975
Data Protocolnone
Focus Zoom Rodnone
Front Diameter Mm85
Summary02
Pentax K-mount prime telephoto lens with a fixed 300mm focal length and maximum aperture of f/4, intended for distant subjects such as sports, wildlife, and outdoor action.
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.