9 out of 10 points and recommendedFast and silent focusing (HSM) - AF quickly latches on to moving subjects. Solid Construction. Zoom Lock. Easy to handhold.Ultra matte-black coat some what prone to scuffing.
Comparing this lens to the Canon 100 - 400 L Series, you get a lot more bang for the buck with the Sigma.reviewed April 24th, 2009 (purchased for $749)
In my opinion, and although image quality between the two slightly differs (with Canon being the better overall), there is not really all that big of a difference (compared dozens of shots on Flickr taken with these two lenses).
In test, it is reported that this Sigma lens delivered excellent range SQF numbers at 120 and 250mm, indicating superior sharpness and contrast. As with most long tele zooms, however, it dipped into the Very Good range at 400mm.
Bottom line: overall it's a good lens and very stiff competition for the Canon in it's zoom range - and at hundreds less in price!
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