Quote Originally Posted by grahamp
The parallax setting on the side of the camera has no effect on the focus, by the way.
Exactly the same applies to the revolving distance rod, of course :rolleyes:.

I agree that you should check the mirror and ground glass position before taking any step. Take some pictures at full aperture or - even better - place a control ground glass on the film rails, and compare it with what you see on the reflex glass. A piece of matt adhesive tape on the central portion of the image frame works as well, provided that you don't push it towards the lens while checking the focus.