Overview

Determine Transformation

In many surveying jobs it is necessary to transform the WGS84 coordinates into a local coordinate system or vice versa.

Using the Determine Transformation wizard, you can determine transformation parameters necessary to perform datum transformations between two sets of coordinates.

To determine a transformation it is necessary to have common control points whose positions are known in both WGS 1984 coordinates and local coordinates. The more points that are common between datum, the more accurately the transformation parameters can be calculated. Depending on the type of transformation used, details about the map projection, the local ellipsoid and a local geoid model can also be needed.

With one common control point, it is still possible to calculate a transformation.

The one point localisation method, allows you to fix specific parameters of the transformation. It requires only one point for the calculation. The method is valid for classic 3D, onestep and twostep transformations.

To use the one point localisation method, select the Use one point localisation method option in the Settings page of the Determine Transformation wizard.

Use one point localisation method

Create a new transformation:

Create a new transformation:

1.	Select the Coordinate System Manager (either from the File tab or inside the project) and then Determine Transformation from the ribbon bar.
2.	The Determine Transformation wizard consists of three steps:Determine Transformation Wizard: Settings.Determine Transformation Wizard: Match Points.Determine Transformation Wizard: Results.

Coordinate System Manager

Determine Transformation

Calculated transformations can be accessed and managed using the Coordinate System Manager.

Depending on the purpose of determining transformation parameters, there are four different transformation types supported in Infinity.