Sigma 30mm 1.4 is crop only, which is a shame and means I'll have to sell mine when I upgrade to full frame, but thats ok, i'll probabbly get a 50mm 1.4 at that point anyway. And then either the 28mm 1.8 or 35 2. Resell prices on the 30mm is just slightly less than what I paid for it new($375 compared to $415) so not a big…
Yeah, I keep a UV filter on my 30mm 1.4, because the front element is fucking huge, and it cost $415 =P. Don't really bother with other lenses. Its really nice to just clean the UV filter if it gets smudged instead of the actual lens. Also I did some tests and didn't notice any difference in quality with/without the filter…