stereographic lenses are a class of fisheye lenses
sterographic lenses are also called “ conform“or “ winkeltreu“
stereographic lenses use image mapping functions of type

maintains angles
| Type : stereographic | weak | medium | strong | max |
|---|---|---|---|---|
| angles | 94° | 131° | 180° | < 360° |
Example of a Stereographic image :

see Fisheye Types