[mapserver-users] request help with projection

[Ed McNierney]

Dave -

You're getting there, but you need to specify the parameters for the
particular Lambert Conformal Conic projection used in that state plane
system.  If I'm reading things right, these are the projection specs:

Standard parallels - 28.3833333 and 30.2833333
Coordinate origin - 99.000 West, 27.8333333 North
False easting, northing - 600,000 and 4,000,000

which means your PROJECTION block should be:

PROJECTION
proj=lcc
datum=NAD27
lon_0=99
lat_0=27.8333333
lat_1=28.3833333
lat_2=30.2833333
x_0=600000
y_0=4000000
END

If someone more familiar with this SPC system could double-check that,
I'd appreciate it.

	- Ed

Ed McNierney
Chief Mapmaker
TopoZone.com
ed at topozone.com
(978) 251-4242


-----Original Message-----
From: David Armstrong [mailto:david.armstrong at ntlworld.com]
Sent: Wednesday, January 09, 2002 10:01 AM
To: mapserver list
Subject: [mapserver-users] request help with projection 




Could someone on the list confirm if i have this correct :-

I need to use projection using 2 layers , one being my map and the other
being my gps , the gps unit is fixed in WGS84 and the datum etc cannot
be
changed , and i am trying to overlay my gps layer on the map.

the map i have is :-
NAD_1927_Stateplane_Texas_South_Central_Fips_4204

Looking this up i belive the map layer  projection should be

PROJECTION
proj=lcc
datum=NAD27
END

and the gps layer  should be

WGS84 Decimal Degrees (EPSG 4326)
PROJECTION
   proj=latlong
   ellps=wgs84
END

Should i just be able to set the output map to the same as the map layer
for
correct use !

any help appriciated , this problem is cracking me up !

Regards
Dave