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Ed,<br><br>
With one minor change (lon_0=110) this worked perfectly. I'm a
newbie at projections, have always just used the shapefiles I had without
any problems. Is there a good tutorial out there for understanding
how to work through projections and determine things like, say the datum
if not specified explicitly?<br><br>
While looking for a good reference for projection definitions and
abbreviations (e.g. Clarke-1866 = clrk66) I came across these
pages:<br><br>
<a href="http://www.safe.com/support/online_help/coordinate-system/coordinate_system_help.htm#predefined_ellipsoids.htm" eudora="autourl">http://www.safe.com/support/online_help/coordinate-system/coordinate_system_help.htm#predefined_ellipsoids.htm</a><br><br>
Is there some better/other resource out there that could be
useful?<br><br>
Thanks again!<br><br>
Dan<br><br>
<br>
At 12:13 PM 2/2/2005, Ed McNierney wrote:<br>
<blockquote type=cite class=cite cite><font face="arial" size=2 color="#0000FF">Dan
-<br>
</font> <br>
PROJECTION<br>
proj=lcc <br>
lat_1=70.0 <br>
lat_2=50.0<br>
lat_0=0.0 <br>
lon_0=-110.0 <br>
x_0=0.0 <br>
y_0=0.0 <br>
ellps=clrk66 <br>
datum=NAD27 <br>
END<br>
<br>
<font face="arial" size=2 color="#0000FF">looks about right.
Remember that you will need PROJECTION blocks for the OTHER layers and
for the top-level map file to accurately describe the other inputs (if
any) and the map image output projections as being lat/lon.<br>
</font> <br>
<font face="arial" size=2 color="#0000FF"> -
Ed<br>
</font><br>
<font size=2>Ed McNierney<br>
President and Chief Mapmaker<br>
TopoZone.com / Maps a la carte, Inc.<br>
73 Princeton Street, Suite 305<br>
North Chelmsford, MA 01863<br>
ed@topozone.com<br>
(978) 251-4242 <br>
</font> <br>
<hr>
<font face="tahoma" size=2><b>From:</b> UMN MapServer Users List
[<a href="mailto:MAPSERVER-USERS@LISTS.UMN.EDU" eudora="autourl">mailto:MAPSERVER-USERS@LISTS.UMN.EDU</a>]
<b>On Behalf Of </b>Dan Barron<br>
<b>Sent:</b> Wednesday, February 02, 2005 2:37 PM<br>
<b>To:</b> MAPSERVER-USERS@LISTS.UMN.EDU<br>
<b>Subject:</b> [UMN_MAPSERVER-USERS] Help to Re-Project Map Layers on
the Fly<br>
</font><br>
<tt>Hello,<br><br>
I am looking for a little help to re-project a map layer to LAT/LON for a
single layer. Below is the <shapefile>.prj file - how do I
define this projection in the layer object of the map file?<br><br>
<br>
</tt>PROJCS["unnamed",<br>
GEOGCS["unnamed",DATUM["D_unnamed",SPHEROID["Clarke-1866",6378206.4,294.978698213901]],<br>
PRIMEM["Greenwich",0],<br>
UNIT["degree",0.0174532925199433]],<br>
PROJECTION["Lambert_Conformal_Conic"],<br>
PARAMETER["standard_parallel_1",70],<br>
PARAMETER["standard_parallel_2",50],<br>
PARAMETER["latitude_of_origin",0],<br>
PARAMETER["central_meridian",110],<br>
PARAMETER["false_easting",0],<br>
PARAMETER["false_northing",0],<br>
UNIT["METER",1]]<br><br>
<br>
Thanks,<br><br>
Dan Barron </blockquote></body>
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