OpenTerrain

A datum shift denotes the procedure of adjusting a geo-referenced position vector from one particular datum to another one, so that the adjusted position vector still maps to the same point on earth. The most prominent method to perform a datum shift is the so called Molodensky transformation.

The term datum shift also denotes the shift of a geo-referenced position in case a different datum has been used mistakenly. Using a different datum can result in a displacement in the range of a few meters up to several hundred meters. In order to achieve sufficient geo-referencing accuracy, it is necessary to reference with the exact same datum.