费格斯说，照相机在光线昏暗的情况下需要使用闪光灯的原因是：闪光给照相机传感器提供大量额外光子，光线正是由这种粒子组成的。
That's why cameras use flashes in low-light environments: the flash gives the camera's sensors an extra dose of photons, the particles that make up light, Fergus says.
一天，我去了一个以前未曾去过的光线昏暗的餐馆，在不需要任何帮助的情况下我就知道该怎么走。
One day we went to a dark restaurant in which I have never been able to maneuver and I was able to find my way with no help.
应用推荐