New Map from Lat,Long - Data Range to Map

Use the Map Tools > New Map from > Lat, Long menu option (NEWMAPLL GX) to create a new blank projected map to fit the range of latitudes and longitudes specified. The projected base map created from a latitude-longitude range will be windowed based on lines of latitude and longitude, not X and Y, and the data window will be oriented to make North up at the center of the map.

The data range can be entered manually, or it can be determined from the range of selected projected data in a database or from the area covered by a grid with a projected coordinate system.

Data Range to Map dialog options

Minimum Longitude, Minimum Latitude	Specify the coordinates of the minimum ground data point to be mapped.
Maximum Longitude Maximum Latitude	Specify the coordinates of the maximum ground data point to be mapped.
Make map center N-S	Select Yes or No to make the map center N-S. Default is Yes.
Coordinate System	Displays the current projected coordinate system.
[Scan Data]	This will scan the projected X and Y channels of the selected database to determine the data range. If the X and Y channels are projected coordinates, the data range is converted to latitude, longitude and displayed in the dialog.
[Scan Grid]	This will scan the dimensions of a grid file to determine the data range and distance units. If the X and Y coordinates are projected coordinates, the data range is converted to latitude, longitude and displayed in the dialog.
[Coordinate System]	The current map projection for the data view in the new map will be displayed in the Coordinate System dialog. The projection can be modified if necessary. The map projection will be based on the data or grid, if these were scanned. If you enter latitude and longitude coordinates manually, you must specify the map projection.
[Next>]	Click the Next button to open the New Map from Lat, Long dialog and create a map with a projected coordinate system based on the longitude and latitude range entered. The output coordinate system cannot be set to Geographic. However, longitude, latitude annotations can be added to the base map. To create a map with a geographic coordinate system, use New Map from X, Y instead.

Application Notes

'New Map from Lat, Long' cannot be used to scan warped data. If the data or grid file projection contains a warp, the warp is removed for the map projection. A rotational warp is added to the map view so that the central meridian of the data window is plotted vertically.

Making Maps from Geographic Data

A database or grid containing geographic data (e.g. latitudes and longitudes, in degrees) can be scanned by this dialog and a map can be created:  a "default" projected coordinate system is created based on the geographic area.

The following procedure is used to create a default projected coordinate system:

• If the map crosses the equator, or if the map is within 20 degrees of the equator, an equatorial Mercator projection centered at the central longitude is created.
• Otherwise, a Lambert Conic Conformal (1SP) projection is created. Global maps outside of +/- 70 degrees latitude are not supported, and hemispheric maps spanning greater than 180 degrees are not supported.