In front of her, the shops would suddenly light up. The street would fill with people and lights.

夜色在身后点滴凝集，面前的店铺骤然亮起灯火，行人和灯光渐次布满大街。

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This time the flash fires just the right amount of light to "fill-in" the subject with the flash produced light. Now you have a rather nice shot where you can see the subject and the background.

然后你再次拍下照片，闪光灯发出刚够照亮拍摄主体的闪光，这一次的照片要好多了，你可以同时看清主体和背景。

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This is because, with a broad source, light rays hit your subject from more directions, which tends to fill in shadows and give more even illumination to the scene.

这是因为光源越广，射在物体上光线的方向就越多，这会起到增加场景中的照明、减少阴影的作用。

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To get creative in challenging light, a built-in pop-up flash supplies extra lighting when capturing images in low-light situations or to provide a fill flash to eliminate shadows.

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