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tmcw / simpleopendata

simple guidelines for publishing open data in useful formats
https://simpleopendata.com/
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Clarify that this is about Geographic CRS #4

Closed tschaub closed 10 years ago

tschaub commented 10 years ago

There are many non-geographic CRS that use the WGS-84 datum.

tmcw commented 10 years ago

Thanks! I'm not sure what non-geographic CRS are, so if you can enlighten me :) Anyway this is a nice no-jargon change that makes things clearer, so the best kind.

tschaub commented 10 years ago

I also wanted to avoid jargon, and I'm sure someone could correct my comment, but by non-geographic CRS I meant a reference system that doesn't use a spherical surface for coordinates or units of degrees.

A reference system might use a transverse Mercator projection (project the sphere onto a cylinder and then unroll) and still rely on WGS84 as a datum - e.g. EPSG:32610 is UTM Zone 10N with the WGS84 datum (while EPSG:3740 uses the same projection and a different datum).