MAGNET Field: Creating a custom datum and ellipsoid

Learn how to create a custom datum and ellipsoid in MAGNET Field.

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MAGNET Field: Creating a custom datum and ellipsoid

  Go to Configure > Coord Sys.

  Click on the three dots (...) in the Datum line.

  Click Add.

Fill in the fields

Name: Enter a name for the custom datum.

Ellipsoid: Select an ellipsoid from the list or click on the three dots (...) to create a custom ellipsoid. 

If you don't need to create a custom ellipsoid, fill out the datum details and click Next.

Adding a custom ellipsoid

Click Add.

Input the ellipsoid name:

  • A: Input the ellipsoid major axis.
  • 1/F: Input the ellipsoid flattening value

Note: Add a note with details on your ellipsoid.

Hit the green check mark to store the new ellipsoid and add it to the ellipsoid list.

  • Ellipsoid: Use the drop-down menu to select the newly created custom ellipsoid.
  • Method: Select the method of transformation:
    • Helmert: Allows the user to enter the offsets and rotations to transform from the datum to WGS84
    • Molodensky: Allows the user to enter the offsets, rotations, and pivot to transform from the datum to WGS84
  • Note: Enter a description for the custom datum.
  • Alias: Set an alias for the custom datum.

Click Next.

  • Offsets: Enter WGS84 offsets dX, dY, dZ.
  • Rotation: Enter WGS84 rotation rX, rY, rZ.
  • Scale: Enter scale in parts per million.
  • Direction: Set the direction, from or to local.

Hit the green check mark to store the new datum and add it to the datum list.

Click on the back orange arrow.

Select your custom datum from the drop-down list. If you don't see it right away, exit the Coordinate System page and go back to it again.