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<P><SPAN class=844584414-10122002>I have a quick question I hope to get some
advise on.<BR></SPAN></P>
<P><SPAN class=844584414-10122002>I am trying to retrace the outline of the US
that is on a weather satellite image. The image is in the form of a polar
stereographic projection (so I've been told).</SPAN></P>
<P><SPAN class=844584414-10122002>I have created a routine that reads map
coastal data for the US (lat/lon values) and run the values through proj.4 and
get output x,y coordinates. I have successfully drawn a map of the US, but
the drawn map doesn't match the image map close enough. It seems that the
northern portion of the map (Maine to Washington state) needs to be narrower,
and the southern portion needs to be wider. This discrepancy is only by a
few longitude degrees, but still not as close as I would like.</SPAN></P>
<P><SPAN class=844584414-10122002>Ok, here are my questions...</SPAN></P>
<P><SPAN class=844584414-10122002>1. Could the problem be in the wrong
ellps that I use? (I have tried several, with not much change)?</SPAN></P>
<P><SPAN class=844584414-10122002>2. Is there any way I can adjust
the input values to modify the map the way I want it?</SPAN></P>
<P><SPAN class=844584414-10122002>I am very new to cartography type stuff,
and still in the learning process, so any suggestions will be greatly
appreciated.<BR><BR>This is what I'm using for input values to get the US
map.</SPAN></P>
<P><SPAN class=844584414-10122002> +proj=stere +lat_ts=90 +lat_0=110
+lon_0=100d40E <BR> +k=1
+ellps=sphere<BR><BR>Another point, the +lat_0=110 seems to be very odd, but
this is the value that I had to input to get the map to somewhat line
up.<BR></SPAN></P>
<P><SPAN class=844584414-10122002>Thank you</SPAN></P>
<P><SPAN class=844584414-10122002>Bryan Ray</SPAN><SPAN
class=844584414-10122002></P></SPAN></BODY></HTML>