In photography, to zoom is to move an adjustable camera lens toward or away from a subject, or by simulating such movement with a zoom lens, making the field of vision gradually narrower or wider. In the manipulation of a digital image, zooming in (or telephoto) is enlarging a portion of an image in order to see it more clearly or to make it easier to alter. Zooming out (or wide-angle) is the opposite; useful for viewing the entire image when the full image is larger than the display space. Zooming is comparable to making a tracking shot, although it is subtly and significantly different from tracking.