# To recalculate the calibration

Recalculate a calibration if the residuals are not acceptable, or to add or remove points.

1. Tap and select Measure / Site calibration.
2. Do one of the following:

- To remove (exclude) a point, highlight the point name and then tap Remove.
- To add a point, tap Add.
- To change the components used for a point, highlight the point name and tap Edit. In the Use field, choose whether to use the vertical coordinate of the grid point, the horizontal coordinates, or both horizontal and vertical coordinates.

3. Tap Apply to apply the new calibration.

Each calibration calculation is independent of the previous one. When a new calibration is applied, it overwrites any previously calculated calibration.