I have found out that the DIgital orthos are Virginia State Plane Coordinate system. Through the metadata on the dvd, I found that although the discs read VASPCS North, The metadata actually refers to the VASPCS south. I metadata also refers to the units in US survey foot. whereas the epsg file refers to metre. I have tried using the information from the meta to create a separate projection, but it is not working correctly. Can you see anything wrong in my translation.
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: State Plane Coordinate System 1983
State_Plane_Coordinate_System:
SPCS_Zone_Identifier: 4502
Lambert_Conformal_Conic:
Standard_Parallel: 36.766667
Standard_Parallel: 37.966667
Longitude_of_Central_Meridian: -78.500000
Latitude_of_Projection_Origin: 36.333333
False_Easting: 3500000.000000
False_Northing: 1000000.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 1.000000
Ordinate_Resolution: 1.000000
Planar_Distance_Units: US Survey Foot
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983 (HARN)
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
I set up in the layer record:(here's the testing map file)
MAP
NAME "City of Harrisonburg, Virginia"
SIZE 400 400
STATUS ON
# SHAPEFILE EXTEXTS
EXTENT 1864266.6510595274 259839.01912492423 1907053.0983945231 299828.4636574
4545
#RASTER EXTENTS
# EXTENT 11360000.0 6820000.0 11390000.0 6870000.0
UNITS FEET
SHAPEPATH "/opt/mapserver/www/htdocs/harrisonburg/data"
PROJECTION
"init=epsg:102746"
END
WEB
IMAGEPATH "/opt/mapserver/www/htdocs/tmp/"
IMAGEURL "/tmp/"
LOG "/opt/mapserver/www/htdocs/tmp/ms.log"
END #end web
# 3876.sid
LAYER
NAME 'layer13'
DATA '/opt/mapserver/www/htdocs/harrisonburg/data/digitalorthos/3885.sid'
TYPE raster
#MAXSCALE 25000
PROJECTION
"proj=latlong"
"ellps=GRS80"
"datum=NAD83"
"lat_0=36.333333334"
"lat_1=36.766666667"
"lat_2=37.966666667"
"lon_0=-78.5"
"units=ft"
END
STATUS ON
END #end layer
# RAILROADS
LAYER
NAME 'Railroads'
DATA '/opt/mapserver/www/htdocs/harrisonburg/data/railroad'
CLASS
STYLE
COLOR 255 102 200
SYMBOL 0
END #end style
END #end class
TRANSPARENCY 80
TYPE LINE
STATUS ON
END #end layer
END #end map
Paul A. Malabad
Director of Information Technology
City of Harrisonburg
(540) 432-7706
------ Original Message ------
From: Frank Warmerdam <[EMAIL PROTECTED]>
Date: Saturday, July 8th, 2006 10:24 AM EDT
To: Paul A Malabad <[EMAIL PROTECTED]>
Subject: Re: [UMN_MAPSERVER-USERS] raster vs shp files extents don't match
Paul A Malabad wrote:
> Corner Coordinates:
> Upper Left (11370000.000, 6860000.000)
> Lower Left (11370000.000, 6850000.000)
> Upper Right (11380000.000, 6860000.000)
> Lower Right (11380000.000, 6850000.000)
...
> Extent: (1880340.635992, 264114.932237) - (1906873.587035, 299715.644746)
...
> I have tried using the different HARN and NAD27 epsg projections in the
> layer, but I think the problem is more basic (at least I hope it is.)
> since the extents are so skewed. Any help or a pointer to the right
> manual would be greatly appreciated.
Paul,
The problem here is that without any coordinate system information for
your MrSIDs you are left playing the "guess the coordinate system" game.
And I would suggest that the rest of us out here in internet land have even
less to go on than you.
If you can't get information from the original MrSID producers, then you
will basically have to mess around with a variety of guesses. The coordinates
for your raster are enormous. If they are in meters then 11 million meters
is roughly 1/4 of the way around the world from the projection origin.
The ratio of x to y coordinates is quite different between the vector and
raster data, so if they are near each other in the real world, it is unlikely
this is just a units issue.
I hate playing guess the coordinate system.
Best regards,
--
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up | Frank Warmerdam, [EMAIL PROTECTED]
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush | President OSGF, http://osgeo.org
