N°100016 · Family detail
PentaxWide·PENTAX K mount·1985
Smc Pentax-A 20mm F/2.8
Specifications01
MountPENTAX K
Focal length20mm
Max aperturef/2.8
TypeWide · Prime
Release year1985
Weight245 g
Filter size67 mm
Min focus distance0.25 m
Max magnification0.12
Aperture blades5
Optical elements10
Groups9
AutofocusNo
StabilizationNo
Aperture controlAperture ring (Manual settings + Auto Exposure setting)
Lens hoodMH-RB67 - Screw-type round
TeleconvertersPentax Rear Converter-A 1.4X-S→ 28mm F/3.9
Pentax Rear Converter-A 2X-S→ 40mm F/5.6
EraFilm era
Production statusDiscontinued
Additional Info02
Lens TypeUltra-wide angle prime lens
Field Notes02
Pentax K-mount 20mm prime lens with a fixed f/2.8 maximum aperture. Designed for wide-angle use such as landscapes, interiors, and general photography.
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Other Mounts03
No alternate mounts are indexed for this family yet.