Are these B&W films? I'll guess that as you mention using different developers. Overexposure would have to be determined by running all the films through a densitometer to read dmax and dmin. A "perfect" exposure may be off but one that you are used to printing with. Your other cameras may be underexposing. Usually viewfinder indication is adjusted independently of actual exposure. They should match but in this case who knows. I seriously doubt manual speeds are off 1.5 stops consistently. Oily magnet will cause over-exposure but it is usually very erratic and unpredictable. Oily magnet would affect auto too, but would be just as erratic. Alkaline batteries (A76 and LR44) are the wrong type for the 2/2N and can cause meter needle errors of 2 stops or more. In this case, auto can be correct, but shutter lockup may result. Alkaline and lithium batteries (also wrong) came out after the camera was designed. 2/2N was designed around silver oxide 1.55v batteries (357, SR44W, G-13, MS76, KS76, 303) and are the only ones that should be used. John, www.zuiko.com