Digital SLRs with a lens focal length of 300 to 400mm are recommended, but you can get away with a decent compact with a 10x zoom.

推荐使用带有300 - 400毫米镜头的数码单反相机，但如果有一架有10倍变焦镜头，性能良好的小型相机也可以。

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If you like taking photos of birds or other wildlife, or if you’re just a peeping Tom, you can get a superzoom camera with a built-in lens with an insane focal length.

如果你喜欢拍摄翱翔天际的飞禽和横闯森林的走兽，或者你想要偷拍对面的心动男孩，你可以选择具有内置镜头和大焦距的相机。

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Using a group of mirrors and a housing that's almost big enough to use as a coffin, Canon was able to stretch the focal-length on this SLR-specific lens to 5,150mm.

佳能的这款单反相机专用折反镜头采用了一组折反镜片，以及一个跟棺材差不多大的镜身，其焦距被拓展到5150 mm。

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By using this adapter to attach any K-mount lens onto a PENTAX Q series camera, the focal length of the lens is extended by approximately 5.5 times in the 35mm format.

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With three glass lens elements in three groups, it can be used as a wide-angle lens equivalent with a single focal length of 30mm (35mm camera equivalent).

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Mastcam-34 has a 34mm lens, or a 35mm-equivalent focal length of 115mm.

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