If necessary, you can edit the values used to compute the ellipse. These values affect the projected coordinates that are computed from Lat/Long.
If you are transforming a survey, the target ellipse values are stored with the survey in the TRV file. All future transformations between grid and geodetic positions will be based on these stored ellipse values.
To change ellipses, pull down the Name list and select the ellipse you want.
To save any changes you’ve made to the ellipse values, choose Save. TPC stores the values under the current ellipse name in the user registry. Any new survey that uses this ellipse will use the changes you saved. Existing surveys have already stored their ellipse values with the survey and will not be affected by the changes you save here.
To add an ellipse, choose New and enter a new ellipse name. TPC copies the values from the current ellipse to this new ellipse and displays them in the Ellipse dialog. Any changes you make to the ellipse values are saved automatically since this is a new ellipse.
You can delete any of the ellipses you do not plan on using. Simply recall the ellipse from the Name list and choose Delete.
Choosing a Survey Grid
Converting Between Grid and Geodetic Positions
Displaying Latitude and Longitude
Importing and Exporting Geodetic Positions
Transform Survey Dialog
Using Coordinate Conversion