Banding is a set of functions performed by placing and dragging the mouse pointer on an image. For example, the zooming of images by placing the mouse pointer on an image, pressing and holding the mouse button, dragging a box around the area of interest, and releasing the mouse button to zoom. Other banding operations include panning and zooming.

Zooming increases scale factors of images within a window. Zooming takes a selected region and extends it over the entire matrix of the displayed CT image. Usually, a zoom reconstruction increases the accuracy of the CT numbers by decreasing the overall size of the displayed image pixels, which decreases the possibility of many tissues occupying a single pixel (partial volume averaging).
Zooming or targeting is not the same as image magnification.

See also Banding.