Zoom Lens

A zoom lens can be thought of as a lens with variable focal length and can be set to either wide angle, telephoto, or any point in between. In this way it can be used as a variable prime and is very useful to adjust the frame size and achieve the ideal shot without having to move the camera nearer to or farther from the subject. Most TV zoom lenses are fitted with a motorized zoom control which allows the camera operator to smoothly zoom in or out during the shot. So the opening frame might be a close up of a bird in a tree and the shot can then develop by zooming out to show the entire tree and surrounding landscape.