렌즈 이물질

It refers to the flaking of the black paint used on the bevels of elements in lenses. The purpose of the paint is to reduce internal reflections in the lens. I don't think it is particular to Schneider lenses, but the construction of the Super-Angulon and some of the other Schneider wide lenses makes this problem more visible than it is on other lenses that h에이브이e more cylindrical elements.
It is largely a cosmetic issue. At worst it slightly reduces the contrast of the lens.

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