N°103609 · Family detail
PentaxPrime·PENTAX 645 mount·1984
Smc Pentax-A 645 55mm F/2.8
Specifications01
MountPENTAX 645
Focal length55mm
Max aperturef/2.8
TypePrime
Release year1984
Weight410 g
Filter size58 mm
Min focus distance0.45 m
Aperture blades8
Optical elements8
Groups7
AutofocusNo
StabilizationNo
Aperture controlAperture ring (Manual settings + Auto Exposure setting)
Lens hoodRH-B58 - Screw-type round
TeleconvertersPentax Rear Converter-A 645 2X→ 110mm F/5.6
EraFilm era
Production statusDiscontinued
Additional Info02
Lens TypeWide-angle prime lens
Summary02
Pentax 645 SMC A is a 55mm f/2.8 prime medium-format lens for the Pentax 645 mount. It’s typically used for standard photography (e.g., portraits and general shooting) with a fast normal aperture.
AI-assisted summary — verify against linked sourcesWhere can this lens be adapted?
The Pentax 645 mount has a flange distance of 70.87 mm. A plain adapter fits a camera whose flange distance is at least 1.46 mm shorter. How lens adapters work
- Pentax 645 DA lenses have no aperture ring. Use an adapter with its own aperture control.
- Sony EAdapter · 52.87 mm
- Canon RFAdapter · 50.87 mm
- Nikon ZAdapter · 54.87 mm
- Fujifilm XAdapter · 53.17 mm
- L-MountAdapter · 50.87 mm
- Micro Four ThirdsAdapter · 51.62 mm
- Fujifilm G (GFX)Adapter · 44.17 mm
- Canon EF-MAdapter · 52.87 mm
- Canon EFAdapter · 26.87 mm
A rear element that sticks out can hit the camera mirror.
- Nikon FAdapter · 24.37 mm
A rear element that sticks out can hit the camera mirror.
Other Mounts03
No alternate mounts are indexed for this family yet.