You get the same amount of light with a large aperture and a fast shutter speed as you do with a small aperture and a slow shutter speed.

你使用大光圈以及慢速快门所得到的光和你使用小光圈以及高速快门得到的光是一样多的。

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Portrait mode chooses a large aperture (a small 'f' number) which will make the depth of field (the amount of your shot in focus) smaller.

人像模式用一个大光圈(f值小)，而让景深(清晰对焦的那部分)变小。

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Since the amount of light reaching the camera is dependent on the aperture, the overall exposure is altered by changes in aperture.

由于光圈控制着进入相机的光线总量，也就是说曝光强弱可以由光圈来控制。

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One stop of light is usually defined as halving or doubling the amount of light entering the camera, depending on the shutter speed, aperture, or ISO changes made.

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Thanks to a larger aperture, floating the entire camera assembly to reduce vibrations, and I suspect a huge amount of software development, the Lumia 920 boasts low light handling abilities closer to that of an SLR than a phone camera.

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