When you mount a lens (whether the camera is on or off), the camera interrogates the lens for its characteristics, including maximum aperture, which one of the focusing parameters.

装上镜头后(不论相机是开着还是关闭的)，相机便会获知镜头特征，包括最大光圈，哪一组对焦参数等。

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Surface mount LED lamp. High efficiency red, super bright green. Lens type water clear.

表面贴装LED灯。效率高红，超明亮的绿色。镜头类型，水质清澈。

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Surface mount LED lamp. Super bright green. Lens type water clear.

表面贴装LED灯。超级明亮的绿色。镜头类型的水清除。

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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.

ENGADGET: Pentax launches Q10 interchangeable lens camera, K-5 II and K-5 IIs flagship DSLRs

Just two days later someone scaled the building and tore out the camera, its mount, lens and cable.

CNN: To surf the Web or surf the surf?

The iOgrapher has a 37mm lens mount to attach wide angle, macro, and fisheye lenses.

FORBES: Connect