>It's true that for any one lens, it will be wider on FX. But >on DX you can use a Sigma 8-16mm wide angle that won't cover >the FX frame, and it has the field of view of a 12mm lens on >FX. There are lots of DX wide angles, so I don't see that as >a strong argument for FX.
You are obviously correct and I have used the excellent Tokina 12-24/4 DX for many years. However, let's not compare apples and oranges - there is no comparison in terms of IQ with the FX Nikon 14-24/2.8.