[masraum]

Originally Posted by LeRoux Strydom

Also do not forget the advantages of the crop factor that you get on the APS sensors, it saves you from buying an expensive 600mm lens for your FF body when you can get the same field-of-view on a DX body with a 400mm lens.

If you take the same shot with the same lens from a full frame camera and then an APS camera, the same picture is in the full frame picture. It just needs to be cropped out. 400mm is still 400mm, not 600.