Tokina 12-24 f/4

I've been looking at this lens, and thought it would be worth trying, as I've read a lot of good things about it, but what about vignetting and all that kind of stuff, when It's going to be used on a 1D? (I guess it gets even worse on a 5D, which I'm eventually going to acquire when I can afford it....).

What about overall sharpness. Good at f/4?

Hoping for some help, and other things to add is also highly appreciated!

Should not be used on a full frame. The 1d will vignette all corners and you'll probably get about 18 MM of the 12-24 on the low end. I love the lens but would not use it an a 1D.

Yes, the Tokina 12-24 is designated DX, which is for the smaller sensors. If you're looking for that particular focal length, you can try the Sigma 12-24 as its for FF. Never used it though so can't really say much for it.

You might as well get the Sigma 12-24 if you want ultra-ultrawide, the 17-40L, or the 16-35L if you don't need to be as wide...since you'll either be limited to 18mm and up or crop anyway.

I would get a wide angle made for a FF vs one for a cropped lens, unless you really like a lot of light falloff/vingetting in your shots, the lens is at best a 18-24. That's a lot of money for a zoom with such a small range.