Quote Originally Posted by Neil Grant View Post
David, not sure if anyone has suggested slight variation at manufacture as a reason for one, ostensibly identical lens performing differently from another. I've had a couple of 50 C lenses both from new, and the second was superior to the first.

No not true. The only difference might be in how the lens was serviced over the years... maybe someone forgot to install the proper shims or missaligned it by mistake.. but not from manufacturer variation.

I've serviced lenses that have been CLAed n suposedly well cared for over the years n noticed edge blackening wipped off as a common problem... causing flare n other customer complaints blaming it on Mamiya's quality control.. but that is just aftermarket carelessness.