Hi, I was out in the snow the other day snapping away. I had a Hoya UV filter on the lens. When I got back inside I noticed some water marks on the filter surface from the snow. Today I tried to clean these marks with cloth/IPA but now I have an area on the filter where there is a mark covering about 20% of the filter. Its like a kind of watermark, only visible when I angle the filter a certain way. I tried repeatedly cleaning it but it will not budge. Have I damaged the filter coating ? Will it affect phtographs ?