Hey! Bought a 35-70 f4.0 zoom from Cheapbay, with the description "loose zoom ring, should not affect quality". But when I got it, I realized it was more or less like a tilt/shift. The zoomring creeps about 2-4mm front to back, and it is very hard to see where the correct position is. Thinking about opening it up and see what I can do, since it was really cheap I don't bother sending it back. Does anyone have any experience with this? On how to do it, etc? Otherwise maybe I can make it tilt/shift even more for a fun effect?