I have two lenses using the 72mm filter size and Im wondering if I should either: Buy step up rings and bring them to 77 (in case I buy 77 AF lenses later) or just buy 72mm filters. One is a 180mm 2.8 telephoto and the other is an 85mm 1.4 (both nikkors). I am thinking a simple UV filter will be ideal to protect the front elements, and have been looking at used ones on adorama. Tiffen good enough or are there better deals out there? I am quite broke. If UV maybe isnt the best do it all filter then Im open to other recommendations too, Ive even thought about graduated.