Wide-angle lens
Appearance
In photography and cinematography, a wide-angle lens is a lens where the focal length is shorter than the diagonal of the image projected within the camera. For a 35 mm camera with a 24 by 36 mm format, the diagonal measures approx. 43 mm. A lens of focal length 35 mm or less is considered wide-angle.
In addition to giving a wider angle of view, the resulting image will also have a certain degree of perspective distortion.
Extreme wide-angle lenses norally do not give a geometric projection, and are called fisheye.
See also: film format, angle of view, normal lens