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I'm trying to make a map of Russia in the Albers projection. My projection string is:

+proj=aea +lat_1=45 +lat_2=70 +lat_0=40 +lon_0=100 +x_0=20 +y_0=20
  +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

Which produces a very nice-looking map, except that the projection is in meters, and I need it in lat/lng. However, whenever I try to remove +units=m from the projection string, QGIS adds it right back in.

How do I get this projection in a coordinate format? Is there a similar but different projection I could use that QGIS will allow to be in lat/lng (preferably that's also supported by d3 or d3.geo.projections, which is how I expect to show these coordinates)?

  • By definition, projections are not in latitude and longitude. So in what sense do you want this to happen? Using "lat" and "lon" for projected coordinates, if that had any meaning at all, would be useless for any analysis, so do you perhaps mean you would like some interactive mechanism to show the corresponding (lon, lat) coordinates of points on the map? Or perhaps you wish to draw a (lon, lat) graticule on a map? Maybe you are re-asking your previous question? – whuber Feb 6 '14 at 14:03
  • I am generating a hex grid in this projection, and since the projection is in meters, the hex grid is also, which means it's not compatible with the rest of my data. Some other QGIS projections (e.g. WGS84) don't appear to use meters at all, and I can generate hex grids in those that have lat/lng data and I can use. – futuraprime Feb 6 '14 at 14:07
  • WGS84 is not a projection, it's a coordinate system. When you generate features in one coordinate system and need them in another, you need to reproject them. Because this is our #1 FAQ, I recommend studying some of our higher-voted questions related to coordinate-system and projection-conversions. – whuber Feb 6 '14 at 14:13
  • I'm aware I could reproject them, but I would rather just generate them in the correct coordinate system to start with. Is this impossible? – futuraprime Feb 6 '14 at 14:42
  • A hex grid in one coordinate system differs from a hex grid in another coordinate system unless those systems differ in an immaterial way (one must be a translation, rotation, and/or rescaling of the other). Thus the actual shapes and sizes of the hexes depend on the coordinate system you use to generate them. – whuber Feb 6 '14 at 14:57

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