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<DIV><FONT face=Arial size=2><SPAN class=145365709-12032010>Hi
All,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=145365709-12032010>I'm having 'fun'
with GeoTIFF and Polar Stereographic projections. My problem appears to be
associated with the 'scale factor' attribute of this projection. It appears that
using the ProjScaleAtCenterGeoKey key makes no difference to the output file
irrespective of the value I give it (at least when viewed in Global Mapper and
other GeoTIFF viewers). </SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=145365709-12032010></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=145365709-12032010>This issue has come
about because my GeoTIFF output files for the polar regions appear to have a
small error in the scaling (of the order of about 0.992) which just happens to
be the average scaling factor for a polar stereographic projection for over 80
degrees (<A
href="http://en.wikipedia.org/wiki/Universal_Polar_Stereographic_coordinate_system">http://en.wikipedia.org/wiki/Universal_Polar_Stereographic_coordinate_system</A>).
I thought I could apply this scaling through the ProjScaleAtCenterGeoKey key on
the geotiff library but irrespective of the value, it appears to make no
difference when I view the file. I have applied the scale factor manually to the
tiepoint and pixscale values which works but it would be better to apply it
through the key IMO.</SPAN></FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1></FONT> </DIV>
<DIV align=left><SPAN class=145365709-12032010><FONT face=Arial size=2>Any ideas
why the output file does not respond to the ProjScaleAtCenterGeoKey?. An example
would be nice. Thanks in advance for any comments or
suggestions.</FONT></SPAN></DIV>
<DIV align=left><SPAN class=145365709-12032010><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV align=left><SPAN class=145365709-12032010><FONT face=Arial
size=2>Dave</FONT></SPAN></DIV>
<DIV align=left><SPAN class=145365709-12032010><FONT face=Arial
size=2></FONT></SPAN> </DIV> <br>
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