Tele-Xenar 75mm f/3.8

Notes and sources

Robot screw-mount telephoto lens, not the Royal bayonet version. The exact M26 lens tested by Ralf Jannke (Digitalkamera-Museum, 2025) is reported as 4 elements in 3 groups, f/22 minimum aperture and 1m native minimum focus. A shorter distance obtained with an added helicoid is not the native lens specification. Existing 41mm/46mm barrel Versions retain their own measured weights and flange-to-front dimensions. The reported 37mm filter diameter on another specimen has not been generalized to all barrels. Exact blade count, filter-thread standard and production boundaries remain unverified; the optical formula is supported by an exact-lens specialist report rather than a manufacturer diagram.