Sigma is touting a new Optical Stabilization system with this lens that gives you 4 stops of stabilization. The new Sigma 120-300mm lens also features two preset modes for OS: Mode 1 for normal shooting and and Mode 2 for shooting subjects that are moving horizontally in front of the camera. Sigma recommends disabling OS when using a tripod. At 120mm, we saw around a couple stops of improvement with OS enabled. It even allowed to get some "Good"-rated shot all the way down to 1/15th and 1/8th of a second. At 300mm, the OS system did a great job as well, with a marked improvement in blur from camera shake, allowing us to get some "Good"-rated shots even down to 1/25th of a second.
At 120mm, we see ...
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| Mouse over this chart to show results with IS activated. |
Zoomed in to 300mm, we see...
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| Mouse over this chart to show results with IS activated. |
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.
