To further complicate focusing, night scenes rarely have enough light or contrast to perform auto focus, nor enough viewfinder brightness to manually focus.

夜景不便自动对焦，因为没有足够的光线或者鲜明的对比，而若手动对焦，取景器亮度又不够，这些使得夜间摄影的对焦更为复杂。

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To increase the keyboard's usability in low-light conditions or at night, auto-adjusting illumination ensures the laser-etched key characters are always bright and easy to read.

ENGADGET: Logitech's K810 keyboard pairs with up to three devices, has a button for switching apps in Windows 8