Sigma 17-50 2.8 EX DC OS

Considering this lens as an upgrade to the 18-55 kit lens on my T3i. The primary reason I'm looking to move on from the 18-55 is the auto focus performance. At the moment, I'm mostly shooting a fast moving 20-month old, and I find the lens is a bit slow to focus and will hunt sometimes, even in lighting I wouldn't consider to be low light. I feel like I'm missing a lot of shots.

Can I expect the 17-50 to find focus significantly faster? A bit faster? Not noticeably faster?

Thanks for any insight.

I've found my copy to be much better at focusing than my 18-55 was. I haven't had any issues with it hunting, even in lower light situations, and it's very quick to lock focus. Big step up from the 18-55 kit lens, you'll notice the differences immediately.

Thanks for the quick reply SoN

timotoby wrote in post #16765163
Considering this lens as an upgrade to the 18-55 kit lens on my T3i. The primary reason I'm looking to move on from the 18-55 is the auto focus performance. At the moment, I'm mostly shooting a fast moving 20-month old, and I find the lens is a bit slow to focus and will hunt sometimes, even in lighting I wouldn't consider to be low light. I feel like I'm missing a lot of shots.

Can I expect the 17-50 to find focus significantly faster? A bit faster? Not noticeably faster?

Thanks for any insight.

Focusing very good. But it makes little noise during low lighting. I think, lens will be wide open during AF. This should help with faster glass with more sensitive center AF point.

Not a great subject. 17mm wide open.

IMAGE LINK: http://www.flickr.com/​photos/khwaja76/131606​17444/

Sports shot. A dunk!!!

IMAGE LINK: http://www.flickr.com …15772304@N02/12​241355605/

50mm f3.2 iso3200.

IMAGE LINK: http://www.flickr.com/​photos/khwaja76/131603​66585/

Nothing special, just testing photomerge in PS.

@ 50mm - f/2.8 - ISO 400 - 1/100s

couple of shots from my 17-50

IMAGE LINK: https://flic.kr/p/mBC5​rB

IMAGE LINK: https://flic.kr/p/mBDd​LT