What some of us DSLR users don't realize until we've grown enough is just how wondrous and useful a good 50mm lens with a wide aperture is.

然而像我们这些单反相机的使用者在有足够多的经验之前，总是很难理解一个大光圈的50 mm镜头是多么的实用。

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The calculated results are presented and a comparison is made regarded to the power received by the aperture, and some useful results for engineering prac...

文中给出大量计算结果，并对不同的口径分布做了比较，得到了若干具有工程意义的重要结论。

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On the other hand, the dedicated aperture ring and exposure compensation dial were incredibly useful, and, with the proper accessories, I could make very good use of the full-size hot shoe on top.

ENGADGET: IRL: Sony's Cyber-shot DSC-RX100 and the full-frame RX1