The white chalk dust goes through the holes in the paper and marks the wood so the carver has a visual guide to begin cutting.

用白色粉笔沿着纸洞描线，在木料上作出记号，这样，木雕师就有了参考样本，开始雕刻。

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Below, a visual guide to Dan Brown's "Inferno" and some the paintings and locations that actually made it into the novel.

WSJ: Dan Brown's Secret to Keeping Secrets

Photo Rumors hears the two shooters will switch to a newer, faster hybrid (both contrast and phase detection) focusing system that also includes Sony NEX-style manual focus peaking, which provides a rough visual guide as to when a subject is as sharp as possible.

ENGADGET: Fujifilm X20 and X100s details reportedly leak, put focus at center stage