I'm using exclusively Nikon-mount (Tamron, Sigma and a couple of real Nikon) lenses with a FotoDiox 'pro' adaptor (the one with the blue stop-down ring) and have been having focussing oddities so I decided to try out the back-focus adjustment as detailed in the manual.
I started turning the mount with the lens focussed on infinity and pointing at a remote tree as described. I turned it and turned it and turned it and turned it. It was getting nearer, I could tell, but it was sticking quite far out of the camera now and when it was very near (but still not right) there must have been a whole centimetre of thread visible! I thought leaving it like this might not be a good idea, given the weight of most of the lenses and the strain that must put on the mount, so I put it back in again and gave up. I'd rather have erratic focussing than a broken camera.
Was I doing something wrong? is there another adjustment I can make or a shim I need to put in place to get decent focussing - or even a different Cmount to Nikon adaptor? My main problem at the moment is the 'infinity' is at the point marked about 2m on the lens, yes really, and I can't get very close to anything with it in focus.
How are other people with Nikon lenses getting on?