[Gdal-dev] scale factor in gdalwarp

Jeff Jacober jeff at terraengine.com
Wed Aug 20 10:44:52 EDT 2003


Im using GDAL to reproject a Spot Quicklook and I seem to be having a bit 
of trouble with one of my projection parameters.

I am using:

gdalwarp -t_srs "+proj=tmerc +datum=NAD83 +lon_0=-115 +lat_0=0 
+k_0=0.9992 +x_0=500000 +y_0=0" -tr 120 120 quicklook.vrt out.tif

The target projection is a custom projection common to Alberta(Canada) 
that we refer to as '10TM'.

The trouble I am having is that my scale factor (which I believe I am 
correct in saying is k_0) doesnt seem to affect the output.  I have tried 
using +k_0=0.8, +k_0=1.8 and +k_0=2.2 and my output file is always the 
same and always has a scale factor of 1.

Any ideas why this is so?

Jeff J

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