Canon 10-18 vs Tokina 11-16, which one is better?

I had the opportunity to test these two lenses together at the same time. My father in law got the Canon, and I already owned the Tokina (be sure you're dealing with the version II of that lens, as it's much sharper).

I found the 11-16 to be noticeably sharper with my copies. I MFA'd two cameras to both lenses in these tests, and it was pretty consistent. Edges were the issue most times. That said, it was a bit pixel-peepish to find the differences. I often care about this, as I shoot wildlife, and I'm frequently cropping to a 1:1 ratio. But with the ultra-wides, I suppose this'll matter much less, as you're not generally cropping in with those sorts of shots.

Tokina has a reputation for flare, but I didn't find that it flared any more than the Canon, and I was specifically looking for this stated weakness.

The big difference between the lenses was the trade-off between aperture and IS. If you are going to do hand-held shots of static subjects, the Canon is for probably you. The IS was quite good, although don't expect to see the dramatic difference that you do with new Canon IS at the end of a super telephoto lens. The wider field of view makes IS a little less important. I perceive 2 stops of real difference, which is pretty much countered by the ability of the Tokina to give you those two stops back via a wider aperture. I should not that it is unusually sharp wide open for a f/2.8 lens.

If, on the other hand, you are going to shoot in light-challenged places (like wide angle close-in landscapes under canopy), then the Tokina is for you. If you are a pixel peeper and hold sharpness above all else, the Tokina would make you happier.

The Tokina, by the way, has been superseded by a new 11-20 model that I haven't had a chance to test. That's about $500.

On cost, the Tokina can be found for about $350 new occasionally. I think someone is offering that right now, or at least they were last week. A quick look at Amazon shows it available for $400. The Canon at $325.

The only disadvantage to choosing the Tokina, other than lacking IS, is its slightly wider size (weight is still pretty insignificant), slightly higher cost.

Other notes:

- I use my 11-16 on full frame at the 16mm setting, and I don't get too much vignetting. I did not test the Canon on that, as I didn't have full frame when I had access to it.

- I don't use the 11-16 much at all any more because on crop I use the 18-35 Art lens, and on full frame, I use the Tamron 15-30. It only gets rolled out, as a result, when I need the super wide range on crop. Which is seldom, as 15mm on the Tamron full frame is equivalent to about 10mm, and the full frame image is superior for those wider shots where I'm not reach limited.

- The lens is one tough piece of glass. I threw a log into a vehicle and managed to hit the 11-16 and an SL-1 camera body hard enough that they came apart. After cleaning it up, it mounted back on the camera and has worked perfectly, even having checked its centering, etc. I did break the ring that holds the hood (glued it right back on), and there is a rattle inside, but it has been functioning for more than a year perfectly since. I was impressed by both body and lens's ability to take such a wildly hard hit and shrug it off. I suspect getting it properly fixed would cost more than a pristine used version, so it's now a permanent part of my collection.