[PROJ] Why is Web Marcator EPSG:3857 so popular for web maps (vs EPSG:4326)?

[Pierre Abbat]

On Thursday, November 26, 2020 8:47:06 AM EST Idan Miara wrote:
> 3. 3857 is "almost" conformal - I think that the normal use case is not
> marine navigation so it doesn't seem so important.

Marine navigation is not the only use of conformal maps. Surveyors use 
conformal coordinate systems (in the USA, they're called state plane 
coordinates, and most of them are Lambert conic or transverse Mercator) to 
note coordinates of lot corners and benchmarks. When I put a tie to a 
benchmark on a map and note the grid bearing to the nearest second, I know 
that the angle between that tie and a boundary line is the same on the ground 
as on the map (though measuring the boundary line's bearing to the nearest 
second is difficult; at 100 m that's 0.5 mm).

Pierre
-- 
La sal en el mar es más que en la sangre.
Le sel dans la mer est plus que dans le sang.