从物体背面照射的光使物体形成全黑的剪影，而背景色调较亮。

Light coming from behind a subject can form a silhouette resulting in object that is completely black against a lighter colored background.

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摄影师们花费了数小时拍摄和打印桌面照片，他们采用白色/银色反光板和黑旗（black flag）使桌面、椅子和地板的光线层次保持一致。

It took several hours to shoot and then print the base image. The photographers used white and silver reflectors and black flags to equalize light levels across the table, chair, and floor.

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这种黑物质不发光，但它远远重于银河系数以亿计的恒星，使银河系的总质量达到太阳的一至二万亿倍。

While it emits no light, this dark matter far outweighs the Milky Way's hundreds of billions of stars, giving the galaxy a total mass one to two trillion times that of the sun.

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So Boston money was probably pretty good because of the Suffolk System but if you tried spending New York money in New Haven Band Note Reporter they would get out the Bank Note Reporter and put a discount on it.

所以，尽管由于Suffolk系统使,波士顿货币很值钱,但是如果你试图,在纽黑文花纽约纸币,他们将拿出,并且折换纸币的价值。

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