I'm debating purchasing a lens with a small scratch due to its heavily discounted price. Its from Ebay (yes I've read the posts ref the pro's / con's buying from here) but as it has undergone a service I'm considering it as working. However it does have a scratch which the seller says has no effect on the image quality. (Its a Canon EF USM IS 28-135mm F/3.5-5.6)
So my questions is, has anyone got scratches on their lenses which don't bother them, if so how big are they? Conversely if you've got a scratch that bothers you, how much does it effect your image and is it photoshop'able out?