Snyder's "Magnifying-Glass" projections?

[toja]

Ref.: John P. Snyder, “Magnifying-Glass” Azimuthal Map Projections, The American Cartographer, 14:1 (1987), 61-68.
http://dx.doi.org/10.1559/152304087783875318

Reference implementation:
https://observablehq.com/@toja/magnifying-glass-projections