2 A B C D E F G H I K L M N O P R S T U V W

stereographic

stereographic lenses are a class of fisheye lenses

sterographic lenses are also called “ conform“or “ winkeltreu
stereographic lenses use image mapping functions of type
r = 2 f tan \frac{\theta}{2}

maintains angles

Type : stereographic weak medium strong max
angles 94° 131° 180° < 360°

Example of a Stereographic image :
stereographic

see Fisheye Types