Hello,

standard SRTM data are limited to latitude between +/- 60 degrees. From this 
page: 
http://www.viewfinderpanoramas.org/Coverage%20map%20viewfinderpanoramas_org3.htm

I downloaded datasets in hgt format which pretend to have elevation data for 
northern regions. I verified one of the hgt files (N67E017.hgt) that it does 
not contain only "NoData Values" (i.e. -32768).

To convert the files to GTif, I followed the instractions from:
http://sourceforge.net/apps/mediawiki/qlandkartegt/index.php?title=Use_SRTM_data_as_Digital_Elevation_Model_%28DEM%29

I used smrtconvert.py, which uses this command:
gdalwarp -t_srs "+proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +ellps=WGS84 
+datum=WGS84 +units=m +no_defs" -r cubic <hgt-file> <tif-file>

When I apply  this to any of the hgt files, I get the message "Using internal 
nodata values (eg. -32768) for image ...". Nevertheless smrtconvert.py creates 
a srtm.tif file. When I attach this to the map in QLandkarteGT, I get no 
elevation information.

I repeated this procedure for a region in germany (far south of 60 degree 
north) with the same result: the file srtm is generated but QLandkarteGT 
doesn't show any elevation data (and all other 3D features are unavailable).

As an additional check, I downloaded SRTM data from http://srtm.csi.cgiar.org
(SRTM_500m.tif and SRTM_NE_250m.tif). Using these data with QLandkarteGT I get 
elevation information. Unfortunately no data northern than 60 degrees.

So my questions:
are there DEM data available for northern scandinavia?
Is antything wrong with the conversion procedure from hgt to tif I used. 
Especially the message "Using internal nodata values (eg. -32768) for image 
..." indicates some problems to me.

I have no experience with geo transformations and the software used for it. I 
just apply recipes from others.

Software: opensuse 12.3

QLandkarteGT-1.6.0-3.1.x86_64
libgdal1-1.9.2-5.7.x86_64
gdal-1.9.2-5.7.x86_64
libproj0-4.8.0-22.4.x86_64
libprojectM2-2.1.0-4.1.1.x86_64

Any ideas

Thanks for Help
Joachim


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