YS mount

For YS mount, flange focal distance (mm) is 55.00; mount type is SLR; format is 24×36 mm; production years is –1969, verified against its source on 2026-08-13.

What the source says

YS mount | 55.00 mm | SLR | 24×36 mm | –1969 | | | | | Sigma, Upsilon, Accura, Polaris, Sun, Aetna, Beroflex, Petri, Raynox, N.P.S., Formula, Dionar, Universal, Soligor, Yashica, Spiratone. M42×0.75 (not to be confused with M42×1) Same as T-mount but with aperture coupling |

— en.wikipedia.org, retrieved 2026-08-13

What briansmith.com says

YS mount | 55.00 mm | SLR | 24X36 mm

— briansmith.com, retrieved 2026-08-13

Sources

• en.wikipedia.orghttps://en.wikipedia.org/wiki/Flange_focal_distance
• briansmith.comhttps://briansmith.com/flange-focal-distance-guide/

Last verified against source: 2026-08-13. Due for re-check by 2028-08-12. This page as Markdown · OKF bundle · full dataset as JSON.