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Making Natural Earth areas whole for global re-projection?

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#1
David Medeiros

David Medeiros

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I posted a while back about the polygon inversion or corruption issue you see when re-projecting Natural Earth data in MAPublisher. Problem was solved by using a larger art board.

My new related issue is that NE data (in this case 1:110m land areas) is divided at the 180* meridian, so the far "east" portion of Russian shows up o the western edge of the art-board with Alaska. I need to use this data as a global locator map and want Russian whole, but when I move the misplaced portion over, join the areas and re project I once again get corrupt polygons with part of russia moving over to the other side of the page.

Any ideas on how to successfully make these area whole so they can be reprojected together or do I need to re project THEN stitch together?

I haven't played with the transformation definition yet, I suppose that may be the trick, moving the central meridian so the break comes not at 180* but somewhere else? I'll try that, but if you have any advice please let me know.

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GIS Reference and Instruction Specialist, Stanford Geospatial Center.

 

www.mapbliss.com

 


#2
David Medeiros

David Medeiros

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Answered my own question, the trick is to move the central meridian over to 11.5* or so. Projections are hard! ;)

GIS Reference and Instruction Specialist, Stanford Geospatial Center.

 

www.mapbliss.com

 





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