June 2017
Beginner
428 pages
10h 2m
English
Content preview from Practical GIS
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Understanding projections
As we know, spatial data can come in different projections. However, we can work with only one projection at a time. In QGIS, we can see our project's projection on the right side of our status bar. It is denoted with EPSG:4326 for us, as this is the identifier of our projection. You might have noticed that since we added the Landsat layer, the projection changed to EPSG:4326 (OTF). This change occurred as the Landsat imagery is in another projection than our project, and QGIS automatically transformed the layer with an on-the-fly (OTF) transformation.
So, if we can transform anything to a well-recognized global projection, why should we care? We can use the Mercator projection that popular web maps (like Google ...