Hi there!

I have 3 Sigmas:

- 70-200 2.8 OS HSM (http://www.sigmaphoto.com/shop/apo-70-200mm-f28-ex-dg-os-hsm-sigma).
Like it a lot! Great lens and cheaper than Canon and Nikkor counterpart.
And I can upgrade for an FX body and keep it.

- 17-50 2.8 OS HSM (http://www.sigmaphoto.com/shop/17-50mm-f28-ex-dc-os-hsm-sigma).
Also like it a lot. Pretty sharp and 2.8 all the way. Nice zoom range. Similar to a 24-70 full frame lens.

- 10-20 3.5 HSM (http://www.sigmaphoto.com/shop/10-20mm-f35-ex-dc-hsm-sigma).
Wanted a super wide for my D5100's DX sensor and was in doubt between this and the Tokina 11-16 2.8. (well, there's also the Nikkor 10-24 and I probably should have bought it) The Tokina is well known for being really good and pretty sharp. It is said to be better than this Sigma. And it is 2.8. But does not have a built-in motor so it wouldn't auto-focus on my body. I think Tokina announced a new model with a motor but there's nothing on the shelves yet.
This one I don't like too much. I don't know. At least my copy doesn't produce sharp images. Well, it can if I use the sweet spot of 8 or 11 f/stop (above 5.6 is already better) but the overall sense I have is that the image quality is poor.

The first 2 are really good.

>Danny - what Sigma Lenses are you using?
>I have a 17-70 which I love and I may try another.
>I was curious what you use and like.
>

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