Brief Introduction for Fisheye Lens
Fisheye lens is a kind of ultra-wide-angle photographic lens with focal length of 16mm or less. Its angle of view is close to or equal to or greater than 180 °. The front lens of this kind of lens is very short in diameter and protrudes parabolic to the front of the lens. Its shape is similar to the eyes of fish, so it is named "fisheye lens".