6 replies to this topic

[Brandon Tourtelotte]

Hello,
I'm trying to export contours I've generated in Global Mapper, using a DEM, but when I try to export the line features as .Shp, for some reason I'm losing
the coordinate reference. When I read the Shp in Arc, it sees the file just fine but doesnt see any spatial reference. Even when I assign the projection
in ArcCatalog it still sees the extents as not corresponding. In other words, it seems to be exporting the Shp file into nonsense space.

I have my DEM files in Global Mapper as LatLong/WGS84. When I export, I've tried every combination of the options the export process gives me - create
the .prj file vs. not, and so on, and nothing seems to make a difference.

Any ideas where I'm going wrong, or has anyone run into this problem before? For any Global Mapper users, can you replicate this? Just open any
DEM, create any contours, and then export a Shp that will show up in the right place in ArcMap.


Best,
Brandon



Brandon Tourtelotte
Cartographer / Sales
Hedberg Maps, Inc.
Minneapolis, MN 55413
bt@hedbergmaps.com

[Brandon Tourtelotte]

I've just been given a tip that my .prj file just isnt specific enough for Arc, and that I need to copy over and rename a file that DOES display properly in Arc in the same LL/WGS84 I'm using. Fool the software basically. I'll try that....

[Rob]

I'm not sure which version you are using, but that problem has been a lingering issue with GM for a couple of releases.

Your workaround is exactly what you need to do.

[Brandon Tourtelotte]

Thus far, I'm finding that even that isnt working. I'll keep trying a few things

In the meantime; can any GM users help? Can you generate contours from a DEM and get them into Shp that Arc will actually see
in an actual coordinate system of any kind? If so, what is your process and what does your .prj file look like?

Oh, I'm using GM v. 8

Thanks.....

[Rob]

in v9 everything works fine... just checked. I also closed the source DEM before I exported the contours to a shapefile. Prj file was written fine... I'd suggest you contact the GM guys; their tech support is usually very responsive.

[sitesatlas]

I don't use Arc, but I've previously had similar problems importing Global Mapper-generated contours into Manifold. I got around it by changing the GM projection to Mercator, exporting the contours, then selecting Mercator as the projection when importing into Manifold. Perhaps something similar might work for Arc.

[Brandon Tourtelotte]

All,
by way of a little closure, I found it was just a silly setting issue. For some reason, GM didnt like my planar units set to arc seconds, and changing it to arc degrees fixed the problem, gave me a good .prj