Gall stereographic projection

It is neither equal-area nor conformal but instead tries to balance the distortion inherent in any projection.

The projection is conventionally defined as:[1] where λ is the longitude from the central meridian in degrees, φ is the latitude, and R is the radius of the globe used as the model of the earth for projection.

[2] Gall called the projection "stereographic" because the spacing of the parallels is the same as the spacing of the parallels along the central meridian of the equatorial stereographic projection.

The reverse projection is defined as : This later (1867) cylindrical projection by Carl Braun is similar, differing only in the asymmetric scaling horizontally and vertically.

This yields a projection tangent to the sphere.