If you are going to get a full frame L lens for a crop camera get one of the 24-x lenses, and then buy a Ef-s Ultra wide. 24-x is fine for an outdoor zoom in wide open places. Save buying the ultra-wide full frame lens for when you buy a full frame camera.
That makes sense, and incidentally is exactly what I did when I decided to buy glass to prepare for the move to full frame later on. I had the Tokina 12-24 f/4 DX at the time, a bombproof piece of kit that was!
« Last Edit: January 26, 2014, 04:12:58 PM by mrsfotografie »
5D3, 5D2, Sony α6000, G16 | SY14 f/2.8, Ʃ20 f/1.8, 24 f/2.8, 35 f/2, Ʃ35 f/1.4A, 50 f/1.8 I, Ʃ50 f/1.4 EX, 100L Macro, 17-40L, 24-105L, 70-200 f/2.8L IS II, 1.4x II, 2.0x III, 70-300L | E-mount: SY12 f/2, 30 f/2.8 EX DN, 16-70 ZA OSS, 55-210 OSS, Metabones SB | FT-QL, AE-1P | FD(n) & FL lenses