N°99232 · Family detail
RicohWide·PENTAX K mount·1982
Ricoh XR Rikenon 18mm F/2.8
Specifications01
MountPENTAX K
Focal length18mm
Max aperturef/2.8
TypeWide · Prime
Release year1982
Weight348 g
Filter size67 mm
Min focus distance0.25 m
Optical elements11
Groups9
AutofocusNo
StabilizationNo
Aperture controlAperture ring (Manual settings only)
Lens hoodBuilt-in petal-shaped
EraFilm era
Production statusDiscontinued
Additional Info02
Lens TypeUltra-wide angle prime lens
Summary02
Ricoh Rikenon 18mm F/2.8 is a Pentax K-mount prime wide-angle lens for general wide views and low-light photography. It has a maximum aperture of f/2.8.
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.