I recently got into MF and bought an RB67 Pro S and picked up, from different sellers on eBay, four 120 and four 220 backs. They all have erratic film advance, sometimes overlapping the images, sometimes spacing them out so far in a couple of the 120 backs that I'd only get five or six images per roll. I recently had two of the 120 backs gone through, new light seals installed, all that sort of thing, and when I got them back I still had the erratic film advance problem. Does anyone have any ideas on how to beat this problem? Is it me? Is there something my camera repair technician doesn't know? I've started a love affair with the RB67 that going to be a long term (well, however much time I have left on the planet) relationship. I love everything about this camera except for the film advance problems.
Thanks for any help.