Global Mapper Pro

Contours to DEM, with geoinformation

pfryscak
pfryscak Global Mapper User
edited December 2009 in Elevation Data
Thank you for the explanation previously given here:
http://www.globalmapperforum.com/forums/elevation-data/4680-how-create-dem.html

When I create a DEM and load it into our software, I lose the geographic information (where the contours and DEM points are on the earth). Is there something I need to do to preserve that?

BTW, what is a "uniform" DEM and how can I insure that Global Mapper produces one?

Comments

  • global_mapper
    global_mapper Administrator
    edited December 2009
    Which export format are you choosing when exporting your DEM and what projection do you have setup on the Projection tab of the Configuration dialog when you do the export? Some software applications will only support loading USGS DEMs that use the UTM or Geographic projections and the NAD27 or NAD83 datums, so you may need to choose one of those prior to export to make the DEM compatible with all software packages.

    I'm not exactly sure what is meant by a "uniform" DEM. Perhaps one where the X and Y grid cell sizes (sample spacing) are the same?

    Thanks,

    Mike
    Global Mapper Support
    support@globalmappersoftware.com
  • pfryscak
    pfryscak Global Mapper User
    edited December 2009
    I use the UTM projection and have also tried the others you suggest.

    Similar problems with some other heightfield formats (GRID, GeoTIFF), so will check if it is not an importing problem.

    A "uniform" DEM, I found out, has the same number of entries in each row. To make sure I got this, I set the option to use the whole area, rather than the convex hull and also choose a regular 10 x 10 sampling pattern for the DEM points.
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