importing 1deg DEMs
TRIMMER at fs.sciences.WLU.EDU
Wed Jun 29 13:36:07 EDT 1994
I have been running into problems with the 1deg. DEMs I've been
importing. When I view the raster file created I have two problems:
1) There is an apperant 'fault line' from upper left corner to lower right
corner. The features are clearly different on one side than the other.
2) The features in general look stretched a bit.
I downloaded the original files from a USGS ftp site. I used the
m.dmaUSGSread command to read the files. I then used r.rot90 to
rotate the data and then r.in.ll to convert to grass raster format.
Could the distortion and 'fault line' be a resault of the way I set up
my region and projection? Is there a suggested method for
calculating cell dementions (resolution) to minimize the distortions
due to the conversion from lat-lon to UTM.
I have four research areas to study that overlap more than one 1deg
block. I intend to patch together the four 1deg blocks that include the
research areas and then create subregions for the research areas.
All suggestions and ideas are appreciated. Thanks
Washington & Lee University
Lexington, VA. 24450
trimmer at wlu.edu
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