Minolta's manual-focus SLR lens SR bayonet mount was introduced in 1958 and continued as the compatible MC and MD mounts through 1998. In 1964, Canon introduced the FL lens mount for their SLRs and continued with the compatible FD mount through 1990. Through all that, there haven't been any adapters to mount one type on the other... until now.

This adapter allows a SR/MC/MD lens to focus to infinity when used on an FL/FD body -- or, more significantly now, on an FL/FD adapter for a digital camera such as the Sony NEX models. Thus, for example, if you have a bunch of old Minolta and Canon lenses, you can use them all with an FL/FD adapter, FD Lens Turbo, etc.

Be warned that this adapter does not fully lock, although the ones I've printed are all very firm fits. Use it at your own risk. On my FD Lens Turbo, the stop-down lever is amazingly close to hitting part of the Lens Turbo, and using sr2fd.stl may interfere with normal stop down. This issue is fixed in sr2fd20130818.stl, which is 0.25mm farther away from the sensor, but still getting infinity focus. As of sr2fd20130827.stl, there is now a stationary "bump" on the adapter that essentially locks the SR/MC/MD lens on the adapter (taking advantage of the material properties of PLA), but the locking action is too aggressive with some lenses and the FL/FD/FDn side is still friction-fit. This remains a work in progress until I have incorporated a complete locking mechanism....