We have carefully tested the Geographic Calculator and reviewed the documentation. If you experience any difficulties with the Geographic Calculator or the documentation please contact us immediately.  Valid coordinates and valid coordinate system definitions are required for valid output.  If the output coordinates seem invalid, check to make sure your input and output coordinate system definitions are appropriate, and that the format of units you have entered match up with the settings you have selected for the units of your input system.  

You may want to refer to your Microsoft Windows User's Manual if you have any questions about the Windows environment, or if you have printing problems.

  So that we may better assist you when you have a problem, please:

  1. Provide us with copies of all files that were being processed when a transformation is in question
  2. Provide copies of comparison results derived from another source, with information about the source

This information is absolutely critical in aiding us in duplicating the problem and helping you in the most effective manner possible.

If you need additional help with the Geographic Calculator, please contact us at

Possible Sources of Error when dealing with Geodetic Data

We perform very extensive error checking within the Geographic Calculator. You may not get the same value you originally entered for a source coordinate when you convert the destination value back into the source coordinate system. Possible reasons:

  1. The source coordinate values you entered may be out of range for the particular coordinate system. For example, a UTM Easting value of 100,000,000 meters will likely yield bogus results when converted to latitude/longitude. Check the source coordinates.
  2. Transformation between the coordinate systems may not be appropriate. For example, converting a latitude/longitude value in France into the Maine East zone of the US State Plane 1927 system is not an appropriate transformation.
  3. You will also notice that if you specify limited precision for a destination coordinate and convert it back into the source coordinate system you may not get exactly the same value you originally entered. Because you can change the value in any coordinate value edit box at any time, the displayed value is transformed, not an internal representation of the value. You should increase the output precision (from the menu bar, select Options>Preferences and click on Customize Unit Display Settings) for the coordinates until there is no significant "round-off" effect.
  4. The values displayed within the coordinate value edit boxes for a coordinate are converted when you change the units of measure or display precision. When you perform a transformation the result is rounded to the precision that is specified at the time of transformation. You will notice that if you increase the output precision of a coordinate that you have transformed the increased precision will only act upon the displayed value. Perform the transformation again to get a coordinate value reflecting the increased "true" precision that you have specified.
  5. If you perform a geodetic forward transformation by entering a source coordinate, a geodetic distance and a geodetic forward azimuth, the Geographic Calculator will calculate the resultant destination coordinate in the destination coordinate system. If you then perform a geodetic inverse calculation between the two coordinates you will see the calculated forward geodetic azimuth, back geodetic azimuth and geodetic distance. If you perform a forward transformation back from the destination coordinate to the source coordinate you MUST use the geodetic back azimuth from the source to the destination as the forward azimuth from the destination to the source. Just be aware that the forward and back geodetic azimuths between two positions are not equivalent unless they lie on the same meridian.
  6. If you copy the datasource file (geodata.xml) to a new directory you must also copy the geocalc.xsd file.If geocalc.xsd is not in the same directory as the datasource file, the Blue Marble Calculator will not be able to load the datasource.

Possible Sources of Error when dealing with Specific File Formats

Troubleshooting file formats starts with size and location.  If the Calculator is having a difficult time loading the file, check the size.  If it is a large file try loading it from a local drive or cached if you are using the viewer.  If you have been working in the application a long time you may want to close out of it and re-open the application to clear out memory.


GML files are built from specific application profiles that are stored in schema files.  These files generally have the extension .XSD, and need to be present when loading a GML dataset.  In some cases, an application schema may be created from a parent schema, so both files would be required.  Make sure that you have all schema files required for your GML dataset when you are using the Geographic Calculator, and make sure they are in the same folder as the gml data.  GML is also a relatively new file format; as such there is limited test data available.  If you have GML data that you would like to share with us for testing and quality assurance, we would appreciate hearing from you.


LIDAR data in general is difficult to work with because the files are large.  The Calculator has some known issues with certain versions of LAS data.  If you are having trouble converting or viewing LAS data, please contact our support team.

Restoring the Default Workspace

A backup version of the default workspace is provided in zipped format in the Backup folder of the installation directory for the Geographic Calculator. This should be C:\Program Files (x86)\Blue Marble Geo\Geographic Calculator for 64 bit machines and C:\Program Files\Blue Marble Geo\Geographic Calculator for 32 bit machines, unless a custom application installation path was selected during installation.

This workspace may be imported in the case where a user needs to restore the original starting state of the workspace for the Geographic Calculator. See Importing and Exporting Workspaces for more information on importing workspaces.


If your license model allows for borrowing of a network license, you will need to return the borrowed license before re-licensing or uninstalling the application. Do not delete the license file if you are using a borrowed license. If you do, the registry key entered for the borrow in HKEY_CURRENT_USER\Software\FlexLM License Manager\Borrow will remain, and will cause compatibility issues with both the application and the server.