Dan, it sounds like you are ascribing the "Schneideritis" effect to the paint on the edges of the glass elements. I see the effect as blisters in the paint on the blackened aluminum, inside barrel. So I don't get your connection to the element edges vs the inside of the barrel. When I pick at this blackened surface it appears to be paint that is baked enamel of some sort. Under a microscope I think I see a pinhole in the paint and within that a white spot that looks like aluminum oxide. But native Al2O3 grows to a few hundred angstrom units depth and then typically stops since it is impervious to air at that thickness.
These white spots are clearly thicker than a few hundred angstoms so appear to be some kind of corrosion chemistry possibly as a result of improper or sloppy surface treatment of the aluminum prior to painting. They vary in size so this is likely a dynamic corrosion process that is continuing over time and quite likely enhanced by local humidity.
Like others here I cannot ascribe any degradation in optical properties with the few lenses I have that show the phenomena but I do worry a bit about some of the spots becoming loose and shedding onto the lens elements.
Yes, Leigh has a good selection of lenses and if I was as wealthy as he I would follow suit. Not because I was afraid of Schneideritis but because those are stunning lenses.
Nate Potter, Austin TX.
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