Pentax's early M42 wide-angle — the Auto-Takumar 35mm f/3.5, a classic vintage wide prime.
The Asahi Auto Takumar 35mm f/3.5 is a wide-angle prime from Asahi (Pentax's parent company) in M42 screw mount, part of the celebrated Takumar lens family that was produced from the 1950s through the 1970s. Takumar lenses are among the most collectible and widely adapted vintage M42 optics.
The lens delivers 35mm at f/3.5 maximum aperture with M42 automatic aperture coupling, manual focus, and full-frame 35mm coverage. The Auto Takumar designation indicates the updated automatic aperture system introduced after the earlier Super-Takumar models.
The Takumar family is valued for its optical quality, smooth mechanics, and the distinctive radioactive thorium glass used in some elements of certain models — which gives some Takumar lenses a yellow tint that largely UV-anneals out over time. M42 adapters are universally available, making Takumar lenses one of the most commonly adapted vintage systems.
Test M42 automatic aperture coupling mechanism. Inspect element colour — some Takumar elements show yellowing from thoriated glass; this reduces in UV light or sunlight exposure over time. Check focus ring smoothness. Inspect coating condition and element clarity.