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Hello,
<br>
I am trying to visualise GOES-16 data, but the output projection
from gdal_translate appears faulty.
<br>
This is the command I use:
<br>
gdal_translate -a_srs "+proj=geos +a=6378137. +units=m +no_defs
+b=6356752.31414 +x_0=0.0 +y_0=0.0 +ellps=GRS80 +lon_0=-75.0
+f=.00335281068119356027 +h=35786023. +sweep=x" -a_ullr $ulx $uly
$lrx $lry [input_file] [output_file]
<br>
<br>
For East Coast USA the results look fine, the output image matches a
coastline shapefile. However, for the West coast the shapefile and
image appear offset by tens of km. The problem is even worse on the
East side of the image (West Africa). An example is available here:
<a class="moz-txt-link-freetext"
href="https://www2.physics.ox.ac.uk/sites/default/files/profiles/proud/goesr-proj-42831.png">https://www2.physics.ox.ac.uk/sites/default/files/profiles/proud/goesr-proj-42831.png</a>
<br>
<br>
I've also tried without +f, without +sweep=x, with various
difference +a and +b values and with different +ellps settings. All
result in a problematic projection.
<br>
<br>
Any ideas what is happened? I've already asked NOAA about this,
their tool (WCT) displays the projection properly. GDAL and NASA's
panoply tool do not.
<br>
<br>
All the best,
<br>
Simon
<br>
<br>
<span class="moz-txt-tag">-- <br>
</span>Dr Simon R Proud
<br>
NERC Post-doctoral fellow in Aviation Meteorology,
<br>
Department of Atmospheric, Oceanic and Planetary Physics,
<br>
University of Oxford,
<br>
Clarendon Lab,
<br>
Parks Road,
<br>
OX1 3PU,
<br>
Oxford,
<br>
UK
<br>
<br>
Tel (office): +44 (0) 1865 282431
<br>
Tel (mobile): +44 (0) 7563 639685
<br>
Email: <a class="moz-txt-link-abbreviated"
href="mailto:simon.proud@physics.ox.ac.uk">simon.proud@physics.ox.ac.uk</a>
<br>
Twitter: @simon_sat
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