Bruce with a Canon wrote:
loaned a couple filters to a friend, when they came back they looked like the had an FBI collection of prints and smudgees on them.
I tried to clean them with microfiber cloths, nuttin. I do not want to use anything agressive to damage the coating (Hoya filters) any suggestions would be appreciated.
I already banned him from using any of my equipment, and he is healing nicely :/
It's good you didn't lend him your camera. :D