Super-Takumar 28mm f/3.5

Asahi's classic wide. The 58mm filter thread stands out in a 49mm system; the drawing is low-drama and even, which is exactly what it was for.

28mmFOCAL LENGTH

f/3.5MAX APERTURE

7e / 7gOPTICS

58mmFILTER

BRANDAsahi Pentax

MOUNTM42

PRODUCTIONc. 1962-1971

MIN FOCUS0.4 m

Before you buy

Aperture blades: dry and snappy. Oil on the blades is the mount's most common disease and a real repair cost.
Look through the glass at a light: haze, fungus threads, and balsam separation all announce themselves. Cleaning marks on front coatings matter less than sellers fear.
Focus ring: smooth, even resistance end to end. Grit or a loose helicoid means a reluble at minimum.
Thoriated designs yellow with age. A week of indirect UV largely reverses it; factor the cast into what you pay.
Auto/Manual switch and pin function: the stop-down pin should move freely and the switch should actually stop down.

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Listings for sale, all conditions

Adapters for this mount
M42 adapters for modern mirrorless bodies