I adjust mine all the time. Very easy with an allen wrench. Just a tiny tweak but if too far no big deal just go back the other way. One quick way is to make sure the infinity falls into place through the view finder, everything lines up. Otherwise I do a close and infinity check with the focus with image taken but infinity images don't tell you much. For close focus, with the camera facing you is is right to left and if back focussing, left to right on the adjustment with the allen wrench. Just a tiny tweak though but again, if you go too far, no big deal just bring it back in.