I recently bought this lens after considering the Canon 10-22 and the new Tokina 11-16, which was still in very short supply.
After about a month of use, I'm very pleased with the Tokina 12-24. I use it with my Canon XTi.
It's a substantial lens, well made. It feels a little heavier than Canon's 17-85 and about the same size.
The Canon option was going to cost nearly 50% more than the Tokina, which I couldn't justify at this point. Today, after using the Tokina for a month, I don't regret saving my money.
Although I know the Canon is a bit wider, the Tokina seems plenty wide enough. The wider perspective is obvious when compared to the 17mm or 18mm of the standard wide angle zooms.
There's nothing small or flimsy about the Tokina, but it is well balanced and operates smoothly. One thing I noticed right away--it zooms the opposite way from Canon's 17-85, which is my every day lens, and other Canons as well.. So to go to the full 12mm position, you rotate the lens all the way to the left, and to zoom to 24mm you rotate to the right (clockwise). At first it feels backwards, but you quickly get used to it.
There is distortion at the wide end where vertical lines flare out at wierd angles. The camera's own angle contributes to the distortion, I think, so the amount of distortion varies even at the same focal length.
I haven't noticed any trouble with the auto focus, although of course the wide depth of field would usually hide any minor errors.
Colors are pleasing, and I haven't noticed any great falloff in sharpness, although I'm not a pixel peeper.
This is my only current non-Canon lens, but now you can count me as a Tokina fan.
For the record: I'm an advanced amateur and started with digital back in 1998 after years of film use.
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