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I have a somewhat odd situtaion. A client has provided me with a Shapefile that has no projection information, along with an image of the map that it corresponds to. I have run some coordinates through WhatTheProj and it matches no known EPSG code.
So, my next thought is to somehow create a projection that maps coordinates correctly. I know how to create a Proj4 string and test whether it's right, but I don't actually know anything about projections or how to go about this. Are there any tools that would help?