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 provide 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 150mm, we see ...
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| Mouse over this chart to show results with IS activated. |
Zoomed in to 600mm, we see...
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| Mouse over this chart to show results with IS activated. |
The Sigma 150-600mm Contemporary's Optical Stabilizer system is absolutely stunning*. Sigma's specs state that the lens features an accelerometer, which aims to improve panning both vertically and horizontally for better performance when photography birds or motorsports, for example. From our graphs, you can see impressive results at both 150mm and 600mm, with shutter speeds dipping well below the typical "1/focal-length rule." At 150mm, even down to 1/15s, we were able to get an 100% keeper rate, and a nearly perfect keeper rate at 600mm. Even down to slower shutter speeds, we found an decent number of acceptable shots.
*However, we did notice some odd, rather distracting jitteriness and twitching of the OS system, that's particularly visible at the longer focal length. It can be difficult to keep the focus point on a small subject; you really notice the focus point jumping and fidgeting around while the stabilization system is active. Our lens technician found the wandering focus point caused by the active OS system to be rather distracting, however, how much of an issue that is while shooting is a matter of personal preference.
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 as we measured here. You can read more about our IS test methodology here: SLRgear IS Test Methodology, v2.
