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What projection does QGIS use?
WGS84 Geographic Coordinate System
In QGIS the default projection, or CRS, is WGS84 Geographic Coordinate System. This CRS has become a global standard for latitude and longitude positions, such as those captured with GPS devices.
What does the Mercator projection preserve?
Although the linear scale is equal in all directions around any point, thus preserving the angles and the shapes of small objects, the Mercator projection distorts the size of objects as the latitude increases from the equator to the poles, where the scale becomes infinite.
How do I choose a GIS projection?
When you choose a projection, the first thing to consider is the purpose of your map. For general reference and atlas maps, you usually want to balance shape and area distortion. If your map has a specific purpose, you may need to preserve a certain spatial property—most commonly shape or area—to achieve that purpose.
What do you need to know about projections in QGIS?
Working with Projections ¶ A Coordinate Reference System, or CRS, is a method of associating numerical coordinates with a position on the surface of the Earth. QGIS has support for approximately 7,000 standard CRSs, each with different use cases, pros and cons!
How does QGIS project data from another CRS?
What this means is that even if the data itself is in another CRS, QGIS can project it as if it were in a CRS of your choice. To enable “on the fly” projection, click on the CRS Status button in the Status Bar along the bottom of the QGIS window: In the dialog that appears, check the box next to Enable ‘on the fly’ CRS transformation.
How to activate on the fly reprojection in QGIS?
In QGIS 2.0, the ‘on the fly’ reprojection is automatically activated when layers with different CRSs are loaded in the map. To understand what ‘on the fly’ reprojection does, deactivate this automatic setting: Go to Settings ‣ Options… On the left panel of the dialog, select CRS.
How many datum transformations does QGIS support?
Datum Transformations A Coordinate Reference System, or CRS, is a method of associating numerical coordinates with a position on the surface of the Earth. QGIS has support for approximately 7,000 standard CRSs, each with different use cases, pros and cons! Choosing an appropriate reference