The same function takes over even if you accidentally move the focus area off the subject for a moment, even in Dynamic AF mode.

当你意外地把对焦区域移动离开主体，这个功能也会被启动，即使用了动态对焦模式。

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Users can lock-on to fast moving subjects throughout the frame using 3D tracking to create sharp images of fast action, or use one of the other modes including single point AF, Dynamic AF and Auto-Area AF.

ENGADGET: Nikon D5200 to reach US photographers in late January for $900