Hi! > The only way to actually see it, is of course to compare to photographs made > by the same lens model, but without the scratches. This is rarely possible. > I do believe, however, that it is very difficult to measure or see any > differences as long as we are talking about a few minor scratches. Scratches > at the rear element will probably have a greater impact on image quality > than scratches on the front element.
I think, just theoretically, that if one had a controlled test environment and compared lens performance with *scratched* highest quality filter versus performance of the lens alone, one might arrive to some theoretically useful conclusions... My general understanding, practical too, is that small scratches on front element of the lens are much less significant to the quality of resulting picture than scratches on the rear element. I am yet to see a lens which exhibits visible image deterioration due to scratches. However, from pure logical point of view, Igor's original remark is correct. Not to mention that not many people have and use controlled test environment for their lenses. -- Boris
