Datums, Coordinate Systems, Coordinate Reference Systems ...

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Datums, Coordinate Systems , Coordinate Reference Systems and datum TransformationsDean C. Mikkelsen, , Warmerdam, OSGeo, FWToolsFOSS4G2007 Sept. 2007 Victoria, BC ! " # $ % " # $ " # & ' " # " # ( # ) $ * # + , - . . $ . / ' 0" # 1 2 2 2 2 2 2 2 2 . . . . . . . . ! 3 # ! 3 # ! 3 # ! 3 # ! 3 # ! 3 # ! 3 # ! 3 # Latitude and Longitude areNOT UNIQUE!NOT UNIQUE!'# / . . # 0" # 1 0" # 1 ! 4 4 . 4 . * 4 . 4 - # "35 ! 6% - $ + ' / Geoid (MSL)SphereEllipsoid / SpheroidWGS72/84. 7 # . 7 # . 7 # . 7 # . 7 # . 7 # . 7 # . 7 # * * * * * * * * " # " # " # " # " # " # " # " # Used for a specific region North America, Europe, South America etc. A Coordinate frame is determined and an ellipsoid chosen to minimize the local geoid-ellipsoid separation. Not Earth centered! Hundreds have been defined for countries all over the planetBEST FITTINGELLIPSOID FORTHE REGIONDatum datum = Coordinate FRAME + Reference ELLIPSOIDEllipsoidSemi Major AxisInv.

Datums, Coordinate Systems, Coordinate Reference Systems and Datum Transformations Dean C. Mikkelsen, B.Sc., P.Eng. Frank Warmerdam, OSGeo, FWTools

  System, Reference, Coordinates, Datum, Coordinate systems, Coordinate reference systems