Coordinate system settings

Coordinate system settings are defined per job.

For other jobs, you must define the coordinate system. You can do this by selecting the coordinate system definition from the coordinate system library provided with Trimble Sync Manager. If required, you can key in additional parameters. This is especially useful if you have your own projection files you want to use or if the job will contain GNSS observations and you want to key in a site calibration adjustment.

The default coordinate system for jobs that do not contain data from Trimble Business Center is Scale factor only with a default scale factor of 1. Use this projection type when the job will contain observations only from a conventional instrument and you are using a local scale factor to reduce distances to the local coordinate system. If you are working in a small area and are not sure which coordinate system to use, use the default setting.

To define coordinate system settings

Use this method for jobs that will contain conventional or GNSS observations or both.

1. In the Create job or Edit job screen, expand the Coordinate system section.

2. Click Define. The Coordinate system definition dialog appears.

3. To select coordinate system settings from the library:

   1. Select the Library tab.

      If you entered a location for the project in the Project properties screen, the map zooms to the defined location.

   2. If required, click in the map to pan and use click the slider below the map to change the zoom level.

      Appropriate coordinate systems for the map location are listed below the map.

   3. To ignore the map filter, disable the Map filtering switch.
   4. Select a coordinate system from the library list or use the Zone, Datum and Geoid fields to select the coordinate system settings.
4. To key in additional parameters:
   1. Select the Parameters tab. Details for the selected coordinate system settings are shown in the Details tab.
   2. In the Projection tab, select the Zone type and fill out the other details as required. To attach shift grid, projection grid or SnakeGrid files, see Projection.

   3. In the Datum tab, select the Datum type.

      The semi‑major axis and flattening values for the selected datum grid file are displayed. These details overwrite any already provided by a specified projection.

      To use a datum grid file, select Datum grid in the Datum type field and select the Datum grid file to use.

   4. To adjust projected (grid) coordinates to fit the local control, select the H. Adj and V.Adj tabs and enter the required parameters.
   5. To use a geoid model file, select the V. Adj tab and select Geoid model and select the Geoid model file.
   6. In the Coordinate type tab, select the coordinate type in the Type field. The default setting is Grid coordinates.
   7. Enter the project height in the Project height field of the Coordinate type tab. For more information, see Project height.

   To set up a coordinate system without a defined projection or datum, select No projection in the Grid files tab, select No datum in the Datum tab and then select the Coordinate type tab to define the project height and the coordinate type.

5. Click Save to return to the Create a job screen.
6. If a project height is required and has not yet been defined, you are prompted to enter a Project height value. For more information, see Project height.

When you have defined the coordinate system and returned to the Create job screen, the following read-only fields are updated in the Datum group of the Coordinate system settings:

• Global reference datum: The datum of RTK measurements, such as the reference frame of base stations including VRS.
• Global reference epoch: The epoch of realization of the Global reference datum.