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<DIV><FONT face=Arial size=2>Hello,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm trying to reproject some images from the Dutch
RD coordinate system (epsg:28992) that is defined as:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>+proj=stere +lat_0=52.15616055555555
+lon_0=5.38763888888889 +k=0.999908 +x_0=155000 +y_0=463000 +ellps=bessel
+units=m <FONT face=Arial size=2> </FONT>+no_defs</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>to utm zone 31N /wgs84</FONT></DIV>
<DIV><FONT face=Arial size=2>+proj=utm +zone=31 +datum=wgs84</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>For the datum shift i guess i need to specify the
+towgs argument also with the source coordinate system. (<FONT
size=2>+towgs=565.04,49.91,465.84,-0.409394387,0.35970519561,-1.868491)</FONT></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I verified these values by running proj.exe and the
results are ok.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>But if i use these proj4 strings with the
gdalwarp -s_srs and -t_srs arguments the resulting images are not as
i expected. It seems that the shift from bessel to wgs84 is not done.
</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>What do i need to do in order to create
images wgs84 from images based on a bessel ellipsoid?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks in advance.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Kees</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
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