There seeems to be a need for expanding further on my comment on page 1. I agree that Canons short lens mount to film plane distance started the use of other types of optics However, I found that some of mine would block the mirror at infonity setting, even if the adapter "auflagemass" was correct, so when the MFT mount came I could use absolutely all former lenses, including Alpa-mount, large cine optics and ancient Leitz products for the M- mount..

p.