Wiechel projection

The Wiechel projection is an azimuthal, equal-area map projection, and a novelty map presented by William H. Wiechel in 1879. It is also a modified azimuthal projection. Distortion of direction, shape, and distance is considerable in the edges.

In polar aspect, the Wiechel projection can be expressed as so:
 * $$\begin{align}x &= R \left( \sin \lambda \cos \phi - \left( 1 - \sin \phi \right) \cos \lambda \right), \\

y &= -R \left( \cos \lambda \cos \phi + \left( 1 - \sin \phi \right) \sin \lambda \right). \end{align}$$