Faced the same choice, saw all the great reviews and great photos
with the Tokina 12-24, bought it -- and got a lemon! I got
consistently soft focus/out of focus shots. I did tests in all
combinations of indoors and outside, near and far subjects, at 12mm
and at 24mm, auto-focus and manual focus. In my research online, I
read that Tokina has had some quality control issues on some of
these lenses -- and I apparently got a bad lens. So I returned it,
got a full refund, and bought a used Nikon 12-24 (still paid more
than for a new Tokina). And I have gotten great results from the
Nikon 12-24, so I am very satisfied; it's a wonderful lens.
My eyes tell me that many people are getting great pictures with
the Tokina 12-24, and my analysis told me it was the best value for
the money. But based on my experience and my subsequent research,
if you decide to go with the Tokina, be sure to buy from somewhere
where you can get a refund or replacement. And test the lens right
away to be sure that you got one that you will be happy with.
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