If you find it tiring to eject the camera's disk icon after importing images into iPhoto, here's one way that you may be able to avoid doing that. Many cameras today have a PictBridge or PTP option. This option is usually found in the setup menu of the camera. Enabling this option prevents the camera's memory card from showing up on the desktop. iPhoto will still see the camera and import photos from it as usual.
When you are finished importing into iPhoto, you can turn the camera off and you won't get a warning message from the Finder.
Mac OS X Hints
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