You have their picture set as background or lock screen (or BOTH!) on your phone.

你把对方的照片设置为手机的背景或锁屏(或两者皆是)。

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If your subject is not in the center of the picture, you need to lock the focus to create a sharp picture.

假若你的拍摄对象不是在照片中央，你就需要锁定焦点已获得清晰的相片。

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If your subject is not in the center of the picture, you need to lock the focus to create a sharp picture.

假若你的拍摄对象不是在照片中央，你就需要锁定焦点已获得清晰的相片。

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