I have a lens where the front element coating is damaged. The center of it has been rubbed away but the edges are still there. Kind of like a donut. The pictures it takes look foggy. The lens itself looks clear. There's no fungus or haze. Could it be the damaged coating causing this? If so, what's a good way to remove the rest of the coating. Yes, I realize that contrast and flare would suffer, but the way it is now is unusable except for the soft glowy look. Some people say WD40 will take the coating right off with my damage to the glass.