打个比方，通过电子取景器，在拍摄前，你可以看到按下快门后的出片效果(白平衡，曝光，对焦等等)。

For example, you can see exactly what effect your Settings will have before you take the shot (white balance, exposure, focus, and so on).

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拍照前闭上眼睛，数到三的时候睁开，这时候按下快门。

Just before the picture is taken, close your eyes and have the photographer count to three. Then open your eyes as he begins shooting.

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在照相前，他调整了快门。

He adjusted the shutter before taking a photo.

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