回复：我家买了一个Sony的数码相机,5.1 mega plxels, Mpegmovie

双影 may be caused by either the shutter speed too slow or mis-focus.

The shutter speed will be slow if the light is dim. To have a clear picture, the minimal shutter speed for most people is 1/60 second with a regular lens at 60 mm or shorter. If you use the lens at 100mm, then you need 1/100 second to get a good picture.

Mis-focus also caused by dim light.

Try to use flash of the camera next time, or put the camera on a tripods to stablize the camera.