GMTED2010 loading in feet
Ice Age Mark
Global Mapper UserTrusted User
Mike,
I have the new (to me anyway) 7.5 arc sec. GMTED2010 that is "breakline enforced. This almost 3GB monster looks really nice, but for some reason it loads in GM with the elevation units in feet, instead of the correct unit of meters. It loads automatically with no choice about this, and the Metadata then says "feet", which is obviously not right. I know I can change the elevation unit interpretation after loading, but how do I get it to load correctly initially? The "prj" file only says "DDZ units". It doesn't seem like there would be a boo-boo on something major like this - but?
All of my GM unit settings haven't been changed and seem to be in order.
Thanks,
Mark
I have the new (to me anyway) 7.5 arc sec. GMTED2010 that is "breakline enforced. This almost 3GB monster looks really nice, but for some reason it loads in GM with the elevation units in feet, instead of the correct unit of meters. It loads automatically with no choice about this, and the Metadata then says "feet", which is obviously not right. I know I can change the elevation unit interpretation after loading, but how do I get it to load correctly initially? The "prj" file only says "DDZ units". It doesn't seem like there would be a boo-boo on something major like this - but?
All of my GM unit settings haven't been changed and seem to be in order.
Thanks,
Mark
Comments
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Mark,
Can you provide the PRJ file? I haven't seen 'DDZ' in a PRJ file before, but we can likely add support for it pretty easily with a sample.
Thanks,
Mike
Global Mapper Guru
geohelp@bluemarblegeo.com
Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation -
Mike,
It's actually an ADF file called "prj" within the compressed zip file (so it won't attach). Here are the contents copied and pasted:
Projection GEOGRAPHIC
Datum WGS84
Spheroid WGS84
Units DD
Zunits NO
Parameters
I see now that the "DD" goes with the spheroid parameter (it looks goofy in notepad), but the Zunits says "NO"(?).
From the documentation:
"The vertical units for the elevation values are integer meters, referenced in most cases to the EGM96 geoid as the vertical datum."
Thanks for looking into this,
Mark -
Mark,
In this case the ZUnits are set to 'NO', which means not specified. Not sure why they wouldn't put meters in there. If the projection was a projected system, like UTM, the Z units should have defaulted to the same as the horizontal units, but since the XY units are degrees that won't work for Z.
In this case the Z units should default to the last selected Z units for some layer that was unknown. In some cases the default will also come from the Elevation Display/Export Units on the Vertical Options tab of the Configuration dialog. You could just change the 'NO' to 'METERS' in the prj.adf and it should come in correctly automatically.
Thanks,
Mike
Global Mapper Guru
geohelp@bluemarblegeo.com
Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation -
Mike,
That worked. Thanks!
Mark
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