Most people tend to think of image stabilization as being mainly for telephoto lenses. While it's true that their longer focal lengths tend to magnify the effects of camera shake, image stabilization can proved a very useful assist at wider angle focal lengths as well; anyone who's ever tried to blur the image of a waterfall, while keeping the surrounding landscape tack-sharp knows exactly what I'm talking about.
At 24mm, we see ...
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| Mouse over this chart to show results with IS activated. |
Zoomed in to 105mm, we see...
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| Mouse over this chart to show results with IS activated. |
While Sigma themselves don't provide a spec on the number of stops the Optical Stabilizer system can compensate for, we found the OS system to work quite well with around 2 stops of compensation at 24mm and around 3-4 stops of compensation at 105mm.
IS systems tend to provide more benefit to less-stable shooters than very steady ones, so most users will see the same or greater amounts of shake reduction than we measured here. You can read more about our IS test methodology here: SLRgear IS Test Methodology, v2.
