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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 Coordinate Calculator or Eye4Software GPS Toolkit using 7 parameters, also called Helmert-7 parameters:

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

Map Datum EPSG#4751 - Kertau (RSO)

Datum Transformation Parameters Kertau (RSO) (to WGS84 datum)

Parameter Value
EPSG # 4751
Map Datum Name Kertau (RSO)
Ellipsoid Name Everest 1830 (RSO 1969)
Conversion None

Ellipsoid Parameters ( Everest 1830 (RSO 1969) Ellipsoid )

Parameter Value
Semi Major Axis 6377295.664
Inverse Flatenning 300.8017

Back to index of all map datums...