N°106023 · Family detail
PentaxWide·PENTAX K mount·1977
Pentax-M SMC 20mm F/4
Specifications01
MountPENTAX K
Focal length20mm
Max aperturef/4
TypeWide · Prime
Release year1977
Weight150 g
Filter size49 mm
Physical length29.5 mm
Min focus distance0.25 m
Max magnification0.12
Aperture blades5
Optical elements8
Groups8
Min aperturef/22
AutofocusNo
StabilizationNo
Lens hoodSlip-on PH-S49 (rectangular)
Teleconverters<No information>
EraFilm era
Production statusDiscontinued
Additional Info02
ModelSMC
FormatFull-Frame
SeriesM Series Prime
Squeezenone
Lens TypeUltra-wide angle prime lens
Iris Blades5
Release Date1977
Data Protocolnone
Focus Zoom Rodnone
Front Diameter Mm63
Field Notes02
SMC Pentax-M 20mm F/4 is a Pentax K-mount prime wide-angle lens for general wide views and landscape or architectural use. It has a fixed maximum aperture of f/4.
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Other Mounts03
No alternate mounts are indexed for this family yet.