Hi all, need some help and advice on cleaning UV filter.. I'm using the Pro1 UV filter for my lens, and got some finger prints on it. Thus, I used the cleaning kit, which comes with the cloth and the liquid that is used to clean lens, to wipe the filter, hoping the stain will go off and the filter become clear. Initially, I checked it was dry and put it back in my dry box. However, 1 week later when I took the lens out to ensure the lens is free of dust and fungus, I realise the liquid that is used to wipe the lens had remained as stain. Hence, I use the micro cloth to just wipe the stain hoping to clear them without any liquid this time. It did clear but still seem to leave some small stains around the filter. Did I just destroyed the filter or something? Or are there any ways to help clear these stains and make the filter clear once again? Hope someone will help me out here, thanks a lot.