Create New Coordinate System

Introduction

The Coordinate System Settings dialog box supports creating a new coordinate system.

Basic Steps

1. In the Coordinate System Settings dialog box, click Create New Coordinate System > Geographic Coordinate System to bring up the Customize Geographic Coordinate System dialog box.
2. In Customize Geographic Coordinate System dialog box, the following parameters need to be set:
3. Name : Set the custom geographic coordinate system name.
4. EPSG Code : The existing ellipsoid, projection coordinate system, and other different combinations correspond with the different ID code (EPSG code). ID code represents a specific ellipsoid, unit, geographic coordinate system or projection coordinates and other information. Its coding ID will be different because of the different projection coordinate system, and the different geographical coordinate system.
5. Datum : Datum is established based on the of the earth ellipsoid, which defines the position of the Earth’s ellipsoid relative to the Earth’s sphere, providing a reference frame for the measurement of surface features, determining the origin and direction of the surface latitude and longitude network, In short, is the positioning and orientation of the ellipsoid. Each country or region has its own datum, and China’s two commonly used datum include: Beijing 54 coordinate system (Beijing1954), Xi’an 80 coordinate system (Xian1980).
6. System Predefined Datum : Click the drop-down button on the right to pop up a list of datum that you can select from a drop-down list of a system-defined datum type. If you choose the ground reference plane provided by the system, reference ellipsoid and ellipse long axis / flat and other parameters are fixed can not be edited.
7. User-defined Datum : You can enter a new name in the text box as the customized datum name. You can customize the reference ellipsoid and ellipse long axis / flat and other related parameters.
8. Reference Ellipsoid : The surface of the earth’s ellipsoid is a regular mathematical surface expressed by a data formula. The surface of the earth’s ellipsoid is commonly used in the measurement and mapping to replace the natural surface of the earth. “Ellipsoid parameters” in the application should choose the appropriate Earth ellipsoid based on the specific circumstances of each country or region. Commonly used ellipsoids in our country include: Krasovsky1940 (equatorial radius 6378245.0 m, flat rate 1 / 298.3), International1975 (equatorial radius 6378140, flattened 1 / 298.257) and so on.
9. System Predefined Reference Ellipsoid : Click the drop-down button on the right to bring up the reference ellipsoid list. You can select a system pre-defined reference ellipsoid type in the drop-down list.
10. User-defined Reference Ellipsoid : you can enter a new name in the text box as the name of the customized reference ellipsoid. You can customize the reference ellipsoid and ellipse long axis / flat and other related parameters.
11. Prime Meridian : Prime Meridian Defines the starting position of the abscissa of the coordinate system. In most coordinate systems, the prime meridian is the meridian via Greenwich, London, England. Click the drop-down button on the right to pop up the list of prime meridians. You can select a system predefined prime meridian type in the drop-down list.
12. After completing the parameter settings, click OK to finish the creation of the new coordinate system.