Quote Originally Posted by 12bolts View Post
How does a permanent marker destroy a camera lens?

Permanent markers aren't really "permanent", next time you want to get permanent marker off a (smooth) surface just colour over it with a white board marker and then wipe it off with a cloth. Even if you used a scribe and permanently damaged the front element, they are replaceable. (They are made that way as the front element is prone to damage). Even so, quality SLR lenses are completely dismantlable, so if you damaged any of the internals they can be repaired/replaced.

Cheers Phil
I was going to reply with the same sentiments but I have never tried the white board markers, I was going to suggest alcohol which does not damage the lens either.
Next time I need to remove a "permanent" marker I'll try your method.