Just curious - I'm interested in opinions about whether you prefer to use protective filters (such as a UV) or not? Personally, I use one when I can verbalize a reason to do so (I'm shooting waterfalls and want to keep splashes off my lens - take it off right before I shoot - or I'm shooting in windy, sandy conditions and don't want blowing sand on my lens). As far as keeping one on all the time to "protect" the lens - well, that's what a lens cap is for. There's something about putting a $20 piece of glass on the front of my $3,000 lens that doesn't sit right with me. As far as "it doesn't degrade the image" goes - stack about three on there and then tell me it doesn't. Just FYI - I am old school (i.e. - I still use that antiquated medium once called "film") - haven't gone pure digital yet and my arguments may be completely inapplicable (is that a word?) in the digital realm. (Not trying to tick anyone off - just thought it would make an interesting debate)