Tamron and Sigma lens on Nikon D5100?

Does Tamron SP AF 17-50mm F/2.8 XR Di II VC and non-VC autofocuses on Nikon D5100?
And does Sigma 17-50mm F2.8 EX DC OS HSM autofocuses on it too?

ANY lens you buy for your entry level Nikon camera must have an on-board auto-focusing system.

Only the Sigma website will give you accurate information.

I can see why you may not want to spend $1, 540 for the Nikkor AF-S 17-55 mm f/2.8, but just take your time when buying generic lenses to make sure you get one that is fully capable of auto-focusing on your camera

The Sigma does - HSM means that the lens has a focus motor (OS is Sigma's version of VR and DC simply means it's optimised for cropped-sensor digital cameras.

You'll have to consult the website about the Tamrons.

The Sigma definitely will work as their HSM designation is the equivalent of Nikon's AF-S (indicating a built-in autofocus motor).

Tamron makes two versions each of their VC and non-VC lenses. Be sure the one you look at has the built-in autofocus motor. I have the non-motor, non VC version and find it is light, sharp, and yields excellent images on my mid-level and pro-level Nikon DSLRs.

Here's a webpage that lists all the lenses that will autofocus on your D5100 body.
http://en.wikipedia.org/...cus_motors