Camera lens should be set to infinity with maximum aperture. then point the camera to perseus or neighbour constellations for a5-minute exposure time and try your luck.

将镜头对焦至无限远，对准英仙座或其邻近星座，把光圈调至最大，曝光5分钟，应有收获。

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This is a technique called Maximum Aperture, and is done by adjusting the Settings on your digital camera to let more light pass through the lens.

这种技巧称为“最大光圈”，通过调整数码相机设置，让更多光线进入镜头，便可完成。

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The PENTAX MX-1 features a 4X optical zoom lens offering a large maximum aperture of F1.8 to F2.5 and 28mm wide-angle coverage (in the 35mm format).

ENGADGET: Pentax launches brass-bodied MX-1 point-and-shoot: 12MP with 4X zoom (update: now with hands-on photos)

This high performance, interchangeable zoom lens features an F2.8 maximum aperture throughout its entire 15-45mm zoom range and is designed for exclusive use with the PENTAX Q-Mount line of digital cameras.

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

When set at maximum aperture and widest angle of view the photographer can use fast shutter speeds in dimly lit locations and take advantage of a beautiful bokeh (out-of-focus) effect in the background.

ENGADGET: Pentax launches brass-bodied MX-1 point-and-shoot: 12MP with 4X zoom (update: now with hands-on photos)