AF-S lens
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Only applicable to Nikkor lenses that came to market in 1996 and after. These lenses focus witth their own built-in auto focusing ultrasonic Silent Wave engine, instead of the focus drive motor in the camera, making for lightning speed focus acquisition. Most useful for fast moving subjects. The first were the 300mm f/2.8, 500mm f/4 and 600mm f/4, all D ED IF AF-S lenses. AF-S lenses with a "II" designation weight less and are generally smaller than their equivalent predecessors.
