[mapserver-users] Projection help: proj command line

[Matthew Pettis]

Hi,

This question is tangential to Mapserver, but critical to me
nonetheless.  I'm trying to reproject a shapefile in a mapfile from

=========================================================
PROJECTION
    "init=epsg:26915"
END
=========================================================

to

=========================================================
PROJECTION
	"+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0
+y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext  +no_defs"
END
=========================================================

my extent in the 'from' projection are:

=========================================================
EXTENT      184056.505 4809728.25 767381.245 5478975.75
=========================================================

Can someone help me figure out what my EXTENT should be in my 'to'
projection?  I've tried the following extents derived from the 'proj'
command line outputs as extents, but was not successful:

=========================================================
$ proj -I -f "%.4f" +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0
+lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null
+wktext  +no_defs
184056.505 4809728.25
1.6534  39.6121
767381.245 5478975.75
6.8935  44.0874

$ proj -I -f "%.4f" +init=epsg:26915
184056.505 4809728.25
-96.8998        43.3739
767381.245 5478975.75
-89.3140        49.4047
=========================================================

Anybody have any ideas what I am doing wrong?  Do I somehow have to
chain projections together to get from my 'from' projection to my 'to'
projection?

Thanks,
Matt

--
It is from the wellspring of our despair and the places that we are
broken that we come to repair the world.
-- Murray Waas