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DaveC426913
Oct26-10, 09:00 AM
I want a projection of Earth where distances are undistorted. i.e. 10 degrees of latitude at the equator is exactly the same map distance as 10 degrees of latitude at the Arctic Circle.

As a disqualified example, the Mercator Projection has map distance increasing with increasing latitude.

I don't care how this distorts the landmasses and oceans, I simply need something with equal gridmarks that can be used in a software program.

Does this type of projection have a name? I'm going to go looking for world maps in this format.

NobodySpecial
Oct26-10, 10:43 AM
They're just called equidistant - you can have a whole range of equidistant projections, conic/azimuthal/etc for a limited area you just have to pick the points you want to fix.

I don't know how you would get an equidistant for the whole earth - it's a little tricky near the poles.

edit see http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj_f.html for examples

DaveC426913
Oct26-10, 11:06 AM
They're just called equidistant - you can have a whole range of equidistant projections, conic/azimuthal/etc for a limited area you just have to pick the points you want to fix.

I don't know how you would get an equidistant for the whole earth - it's a little tricky near the poles.


Yes, it tends toward infinite horizontal zoom near the poles. That's OK.

I'm having trouble finding any but the cheesiest of maps, as if drawn by a grade-schooler.