Summary: The autofocus is plenty fast and the lens is sharp. The controls are smooth and it just feels good in my hand. The Optical Stabilazation is very good. I have used this lens repeatedly carrying it only in hand, and my images came out very sharp.
Summary: Just bought this lens after using a Canon Non IS version of this lens. The only thing that is different in a negative way is the autofocus. The Canon lens does focus faster, but, not a very noticeable amount. This lens focuses fast enough for me, but I trust the Canon more. Build quality is much better than the images online give it credit. I love the feel of the lens, the weight is awesome too, much lighter than the Canon version.
Summary: Simply amazing lens!! Super sharp and precise, gorgeous bokeh, maybe it is me but feels that my photography is more live when i use it...! I'd buy it again if lost, it comes with me everywhere i go along with my 17 - 50 f/2.8 also by Sigma. Quit fooling around buy it!!
Summary: Not sure if I just got a bundle of bad glass, but I couldn't get this lens to focus on my D7000. Tried it for 2.5 weeks, making many adjustments to fine-tune focus settings, still no joy. 70mm was back focused, 200mm was front focused. For $1000+ I expected better quality. I'll be saving up for the Nikon 70-200mm, may rent and try out the Tamron in between.
Summary: I am not a pro, but do take a lot of photos; especially sports. I am team photographer for my kids soccer teams. I needed something faster for shooting under the lights; this does that. No need for a flash at all. There are circumstances that if in auto mode, the pic is over exposed. If you know how to adjust the camera this can be compensated for. I do wish for a little more zoom length.
The build quality seems to be very good although the lens is not metal like the Canon
27 August 2014
Summary: This lens was highly rated against the Canon equivalent at half the price. The only complaint was that it was not as rugged as the Canon. I am not a professional and do not subject my equipment to some of the rigors of a working photographer so I don't worry about this. The build quality seems to be very good although the lens is not metal like the Canon. All the controls are smooth in use.