I may have to eat my words on the film being fogged across the entire sheet. After putting it on the densitometer it is obvious that there is fog across the sheet. I guess my old eyes aren't as trustworthy as they use to be. I went out and shot more film. I did notice the rib lock wasn't seating tight in the camera back and sure enough it was holding the holder away from the back just a hair. The fix is just milling a little more off the rib. But I would still like a tighter fitting film rail. But I don't think that is what is causing this problem so I guess I will live with that. Thanks guys for the input. Robert