SMC Pentax-M 50mm 1:1.7

This is the standard lens that you would expect to receive on one of the early Pentax camera bodies, it is a great lens!

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Pretty sure this is one of the first photos I took with this lens. British Museum, 2013.

In Production: 1977 to 1984
Image Format: Full Frame / 35mm
Lens Mount: Pentax K
Aperture Ring: Yes
Diaphragm: Automatic, 6 blades
Optics: 6 elements, 5 groups
Aperture Range: F1.7 – F22
Focusing: Manual
Min. Focus: 45cm
Filter Size: 49mm
Field of View (Diag. / Horiz.): APS-C: 32 ° / 27 ° Full frame: 47 ° / 40 °
Coating: SMC
Diam x Length: 63 x 31 mm
Weight: 185g

Pigeon Friend
Pigeon Friend in London.

There are a ton of great reviews for this lens over at Pentax Forums