Cartographic system

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• Setting the cartographic system is necessary when coordinates of points must refer to a system defined by a reference projection, datum, ellipsoid and transformation parameters.

• The cartographic system can be used for:

  • The calculation of geographic coordinates of GPS instruments.

  • The calculation of the scale factor to apply to distances measured with total stations

• The software allows to select a predefined system or define a system with specific parameters.

• Click Job.

• Click Coordinate System.

• Click Cartographic system.

Select a predefined system

• X-PAD includes predefined cartographic systems for most of countries.

• If a cartographic system is not already assigned, clicking Cartographic system shows this message.

  

• Click YES to select a predefined system.

• This opens a new window where to select the predefined system for a specific country.

  

  • Group: select the country or a group of systems (like UTM systems).

  • Systems: shows the available systems for the selected group.

• Select a system to load the parameters.

• Click Accept to confirm the selection.

• If the cartographic system is changed changed, the software asks if the points already available in the job, with a valid latitude and longitude, have to be recalculated in the new system.

  

  • All points: recalculates the coordinates for all points in the job with a valid latitude and longitude in the job.

  • No points: coordinate of points are not recalculated in the new system.

  • GNSS points: recalculates the coordinate only for points measured with a GNSS receiver.

  • TPS points: recalculates the coordinate only for points measured with a total station.

  • Imported points: recalculates the coordinate only for points imported in the job.

  • Other points: recalculates the coordinate for points calculated, for example in COGO, or manually entered.

Cartographic system parameters

• Each system, predefined or manually enter, is defined by different parameters.

• In Projection & Datum page the type of projection, datum and ellipsoid is defined.

  

  • Name: name to assign to the system.

  • Projection: cartographic projection to use.

  • Datum: datum to use to convert from the WGS84 ellipsoid to the cartographic system ellipsoid. Click the field to access a list of default and user-defined datum.

  • Ellipsoid: ellipsoid of the cartographic system. Click the field to access a list of default and user-defined ellipsoids.

• Parameters page lists the parameters of the projection. The parameters in this page depends on the projection selected.

  

  • Lat. Origin: Defines the latitude of the origin of the coordinate system.

  • Long. Origin: Defines the longitude of the origin of the coordinate system.

  • Parallel 1: Specifies the first parallel for the coordinate system.

  • Parallel 2: Specifies the second parallel for the coordinate system.

  • False East: Defines the coordinate for the false East of the coordinate system.

  • False North: Defines the coordinate for the false North of the coordinate system.

  • Scale: Sets the scale factor of the coordinate system.

Save a cartographic system as predefined

• It is possible to save a cartographic system as predefined for all the jobs.

• While in the Cartographic system page, click Tools.

• Click Save as predefined.

• Save the current system in the User group of the predefined systems. The system can then be used in other jobs.

Cancel current cartographic system

• This command allows to cancel the current selected cartographic system.

• While in the Cartographic system page, click Tools.

• Click Cancel current cartographic system.

• Now the cartographic system is not defined.

Export in WKT format

• A cartographic system can be exported in the standard format WKT. Well-known text (WKT) is a standard text format for describing coordinate reference systems. It's used in geographic information systems (GIS) and web mapping APIs and can be used in different software.

• While in the Cartographic system page, click Tools.

• Click Export in WKT format.