Cropping an image is a very usefull method of bringing your attention to the main centre of interest of the image. If images are take with a camera with a high megapixel count then there is a lot more room for cropping, compared to an image from a camera with a lower megapixel count. Cropping an image will loose some detail in the image, however it may give the image much more impact.

The original image of the F111 is shown above, together with a cropped image below. The cropped image appears to have more impact due to the emphasis on the main subtect matter, the aircraft.

Cropped Image