[PROJ] Transverse and oblique Mercator

[Pierre Abbat]

On Wednesday, 15 January 2020 18.11.24 EST Melita Kennedy wrote:
> John Snyder discusses 4 different oblique Mercator implementations on page
> 162 of his book Flattening the Earth. Rosenmund's was first and is used in
> Switzerland. It's not quite the same as Hotine's which is used in Alaska,
> but it's close enough that Esri, at least, is using Hotine's version for
> Switzerland. Madagascar uses Laborde's version. It converts to a conformal
> sphere, then uses a spherical transverse Mercator, and finally a 3rd-order
> complex-algebra transformation to make it oblique. It cannot be emulated
> with Hotine with a reasonable accuracy. Snyder also lists one designed by
> Cole for Egypt, but it's not in common use.

http://mapref.org/ObliqueMercatorProjection.html says that Rosenmund's version 
is simply a conformal projection from the ellipsoid to the sphere, followed by 
an oblique Mercator projection of the sphere. That's easy.

Should I get Snyder's book? Your book?

Pierre
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