When setting up a conversion where the input datum differs from the output datum, a Datum Transformation is required. In order to select a Datum Transformation, one or more transformations must be defined in the geodetic data source that transform from your input datum to the output datum.
With your input and output datums selected for
your input and output coordinate systems, double-click in the Datum
Transformation box between the two coordinate systems.
If you begin to process the job without having selected a Datum Transformation, you will be prompted to do so, if one is necessary.
If no transformation is needed, a message stating this will appear in the display box. If no valid transformations are found between the two datums, a warning message will display.
Otherwise, the Select Datum Transformation dialog
will display, listing available Datum Transformations in folders by method.
need to select an appropriate datum transformation for your coordinates.
the parameters for any datum transformation, either right-click on it
and select Info, or select the transformation and click the information
button below the list of transformations.
With the desired Datum Transformation selected,
click OK to return to the main
job page. The
selected transformation will be shown.