Martin, That did it. It is in Nevada. I don't know if it's a stateplane coordinate system with an unusual false easting and northing or something else.
I replaced "Local" with "Transverse_Mercator". The reprojection worked. I compared the results with what ArcMap calculates, and the greatest difference is < 1 cm. That's good enough for what I'm doing. Thank you for the help. Bryan > Looks to me like it is a state plane projection for somewhere in Nevada. > Maybe try using Transverse Mercator as the PROJCS. I'm not a GIS pro > though > so take my advice with a grain of salt. > > Martin > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Bryan Keith > Sent: Wednesday, May 20, 2009 2:11 PM > To: [email protected] > Subject: [gdal-dev] Local coordinate system and proj4 > > Hello, > > I've been sent an ESRI coordinate system file (.prj) that looks like this: > > PROJCS["Unknown",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984 > ",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.01745329 > 25199433]],PROJECTION["Local"],PARAMETER["False_Easting",68396.30349583333], > PARAMETER["False_Northing",207061.59375],PARAMETER["Scale_Factor",1.0],PARAM > ETER["Azimuth",0.0],PARAMETER["Longitude_Of_Center",-117.0],PARAMETER["Latit > ude_Of_Center",41.29],UNIT["Foot_US",0.3048006096012192]] > > When I try to use this definition in proj4 using ogr tools, I get this > error: > > ERROR 6: No translation for Local to PROJ.4 format is known. > > Is there a way to use this projection information with proj4? ESRI ArcMap > seems to be to translate from these coordinates to lat-long WGS84. > > Bryan > > _______________________________________________ > gdal-dev mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/gdal-dev > > _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
