Sony a7r lens adapters - 1 per mount type enough?

[Hening Bettermann]

I am planning to buy the a7r and wonder how many adapters I need for my Contax lenses.

Could the adapter stay on the camera rather than on the lens? If so, 1 adapter per lens mount type would be enough.

For lenses adapted to e.g. the Canon 5D2 this would be out of the question, of course, because the adapter is so flat, and the release mechanism unaccessible from the outside. But the Sony adapters look so long that it might be possible. Does anybody know?

[Telecaster]

One adapter per "legacy" mount is IMO fine provided it's of sufficient quality to hold up to repeated mounting & dismounting of lenses. That's how I do it. My Y/C Zeiss adapter, a Novoflex, is plenty long enough to stay on the camera permanently. It provides correct infinity focus too.

-Dave-

[Jim Kasson]

One adapter per "legacy" mount is IMO fine provided it's of sufficient quality to hold up to repeated mounting & dismounting of lenses. That's how I do it. My Y/C Zeiss adapter, a Novoflex, is plenty long enough to stay on the camera permanently. It provides correct infinity focus too.

The part about the infinity focus is definitely not true for all adapters. In fact out of a sample of six a7/Leica M and a7/Nikon F adapters from three manufacturers I have found not one that has proper infinity focus. and is specifically not true for the Novoflex a7/Nikon F adapters that I have. There is reason to believe that this is intentional on the part of the Novoflex.

If you find an adapter that provides correct infinity focus, so that the markings on your lens are accurate, that's a good reason to leave that adapter on the body.

Jim

[Hening Bettermann]

Thank you for your answers. Telecaster, that is good news. Jim, it is still good news. I don't think my C/Y lenses have floating elements, and on my lenses, I replace the distance scale with a millimeter scale anyway (as an aid in focus stacking). Which also will make it easy for me to make my own infinity marks, if otherwise I can define "infinity". When focus stacking using live view and 10x enlargement, I have found out that I need to define the 'furthest point' (rather than 'infinity') by eye sight anyway.
Good news, and thanks again!