That's a very helpful presentation, thank you. I used a M42 to Pentax-K adapter but the adapter moves a bit even thou it is locked in, it causes information to be send to the camera over the contacts when the lens is moved a bit (as in focus ring is touched). Causes the live view to be stopped as soon as the lens moves a bit with the adapter. And that's with the genuine 70$ adapter ring :/ I think i'll try a M42 to EF Adapter with my old EOS400
