lens

Wide-angle

Camera lens has a point of focus, which is a short distance from its optical center; meaning that it has a wide horizontal field of view. These lenses are available in different sizes and some can actually cover an area wider than the eye can see. Wide-angle lenses provide a deep perspective, or DOF so that all the elements seen through the lens will appear in a sharp focus.

Zoom

Zooming out gives the photographer a wide-angle view that captures a wide scene. When you zoom in, the field of view narrows and you can focus on small portions of the scene without having to physically move closer.

Long focus

A long-focus lens is any lens with a focal length longer than normal. A long-focus lens brings far subjects closer, like a telescope. They therefore have a smaller angle of view than a normal or wide-angle lens.

Telephoto

A camera lens that has a narrow angle of view, and a longer (than usual) focal length. The effects of a telephoto lens are similar to binoculars; the image is magnified making the subject seem closer than it actually is.

Retro focus

Type of wide-angle lens designed so that the space between the back of the lens to the focal plane is longer than the focal length, for example; in single-lens reflex cameras in order to leave space for the mirror to move.

Quasi fish-eye

A fisheye lens is an extreme wide-angle lens that makes the image appear to wrap around in a circle.

  

Catadioptric

A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses dioptrics and curved mirrors catoptrics . Catadioptric combinations are used in focusing systems such as search lights, headlamps, early lighthouse focusing systems, optical telescopes, etc. Other optical systems that use lenses and mirrors are also referred to as "catadioptric" such as surveillance catadioptric sensors.

Macro

A lens used for close-up photography that produces a life-size or larger image on film, with a minimum of 1:1 object-to-image ratio.

Teleconverter  

A teleconverter (sometimes called tele extender) is a secondary lens which is joined between the camera and aphotographic lens. Its job is to enlarge the central part of an image obtained by the objective lens.

Tilt-shift  

Tilt-Shift miniature faking is a creative technique whereby a photograph of a life-size location or object is manipulated to provide an optical illusion of a photograph of a tiny scale model.