Property me the UV filter misappropriated risen as lens protection glass. Since I photograph animals often and like to go twice with wet nose sniffing up close, this has been already paid. Dear I clean this filter than the lens glass. And above all, I would rather buy in the event of a scratch a new filter, instead of crying to sit in front of a ruined lens) The whole makes only sense if the filter is not of itself affect the picture quality. In my comparison photos, I could not find anything negative in this regard.