The best way to clean a lens is to use a piece of lint free lens cleaning tissue and a small amount of lens cleaning solution. Place a drop or two of cleaner on the tissue (never directly onto the lens) and then wipe the lens in a circular motion, removing any marks or smear. Additionally a smaller blower brush can be used to simply blow off or brush away loose dust. If the above supplies are not available a clean, dry, soft, lint free cloth can be used to clean the lens. The same method can be used to clean the viewfinder eyepiece of Nikon cameras.
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