If the venue of your presentation is not adequately light-proof, select a dark-colored background and use any light color for text.

如果演示的地点不具备足够的防光性，请选择深色背景，并为文本使用任何浅色。

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Also, most apps built for reading longer pieces (like Instapaper or Stanza) will let you swap colors, putting white text on a dark background.

同时，许多app软件适合于长时间阅读(象instapaper或者Stanza)会允许你改变颜色，如白色字体的文本放到黑色的背景上。

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To make sure that the cameras are accurately recording small changes in reflected light, engineers look for a bright light against a dark background to provide a reference point.

为了确保相机准确地记录来自反射光的细微变化，工程师寻找暗背景上的亮光，来提供一个参照点。

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For more background, see my 2008 magazine article about these practices, Dark Journalism.

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