Coordinate System Information (SPOTView Only) - 2023

The first step in registering a SPOTView™ SPOT image is assigning the appropriate coordinate system. The image's .HDR file should contain all the information you need to determine the proper coordinate system.

Occasionally you will want to open a SPOT image that uses a coordinate system not currently supported in MapInfo Pro. When this is the case, you'll need to modify MapInfo Pro's list of supported coordinate systems by adding a new line to the MAPINFOW.PRJ file; this is an ASCII file that can be easily modified with a text editor. Adding Projections to the MAPINFOW.PRJ File gives a complete description of how to edit this file and what elements to use within a line for a given coordinate system.

For example, in the sample .HDR files settings above, the PROJECTION and DATUM settings might lead you to believe that one of MapInfo Pro's standard Albers Equal-Area Conic coordinate systems would be appropriate for the sample SPOT image. But if you examine the MAPINFOW.PRJ file, you'll see that the Albers Equal-Area Conic coordinate system lines look like this.

"--- North American Coordinate Systems ---"		
"Albers Equal-Area Conic (North America)", 9, 62, 7, -96, 23, 20, 60, 0, 0		
"Albers Equal-Area Conic (Continental US)", 9, 62, 7, -96, 23, 29.5, 45.5, 0, 0			
"Albers Equal-Area Conic (Alaska)", 9, 63, 7, -154, 50, 55, 65, 0, 0			
"Albers Equal-Area Conic (Hawaii)", 9, 62, 7, -157, 3, 8, 18, 0, 0

Comparing the origin and standard parallel settings (arguments 4 through 7) to the ORIGIN_LON, ORIGIN_LAT, STD_PARALLEL_1, and STD_PARALLEL_2 settings in the .HDR file shown above, you will see that they do not match up. In this case, you would need to add a line like this to the MAPINFOW.PRJ file:

"Albers Equal-Area Conic (St. Louis)", 9, 62, 7, -96.5, 0, 36.6, 43, 0, 0

Note that when adding a new coordinate system for an image, if a required setting is missing from the .HDR file, enter zero in its place. In the sample line above, for example, zero was used for the False Easting and False Northing settings-the final two arguments on the line.