Eye4Software Hydromagic

Professional hydrographic survey software

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A map datum is a reference from which measurements are made. In geodesy, a geodetic or map datum is a set of reference points on the earth's surface against which position measurements are made, and (often) an associated model of the shape of the earth (reference ellipsoid) to define a geographic coordinate system. Some examples of geodetic datums are: NAD27, NAD83, ED50 etc...


An map datum can be defined in the Eye4Software Hydromagic using 7 parameters, also called Helmert-7 parameters:

Also an ellipsoid has to be specified when a map datum is defined.

List of map datums supported by Hydromagic