Fisheye lenses

A fisheye lens is a type of ultra-wide angle lenses with extreme 180 degree angle of view. Unlike conventional wide-angle lenses, fisheyes are not corrected for distortion - strong barrel distortion is a characteristic of all lenses of such class.

Fisheye lenses are normally used for specialized purposes and unusual special effects in advertising, commercial, scientific, surveillance, meteorologic and astronomic photography, but also popular for shooting extremely wide landscapes, interiors, action sports and even funny close-up portraits.

There are two types of fisheye lenses:

• a circular fisheye produces a 180 degree angle of view in all directions (horizontal, vertical and diagonal) and the image circle of the lens is inscribed in the image frame;
• a diagonal fisheye produces a 180 degree diagonal angle of view and covers the entire image frame. For this reason diagonal fisheyes are often called full frame fisheye lenses.