 |
|
 |
|
|
||||||||||||||||||||||||||||||||||||
RRG GIS DatabaseGeneral information - Projection and resolutionThe database is available at scales of 1:1.000.000, 1:500.000 and 1:200.000, depending on the country concerned. Scales of 1:1.000.000, 1:500.000 are used in Scandinavian regions as well as for the far east European countries; scales of 1:500.000 are also used for south European countries, whereas scales of 1:200.000 are used for central Europe, Benelux countries and Alpine regions.The database is maintained in a Lambert Conformal Conic Projection with the two standard parallels at 27° and 63° North, the central meridian at 10° East and the map origin at 10° East and 52° North. The projection parameters can be summarised as follows: Projection: Lambert Datum: (none) Units: Meter Spheroid: Clarke1866 1st standard paralell: 27 0 0.000 2nd Standard paralell: 63 0 0.000 Central meridian: 10 0 0.000 Latitude of projection’s origins: 52 0 0.000 False easting (meters): 0.000 False northing (meters): 0.000 This type of projection is best suited for European-wide databases and analysis. The main criterion for the choice of these particular standard parallels was to preserve as best as possible the length of line segments for main parts of central Europe, notwithstanding distortions in Scandinavian regions and areas in southern Europe. With both the digitisation scales and projection chosen the database is optimised for applications and analysis on the regional, national and European scale. In contrast, this database is disadvanced for applications and analysis to be performed at local or sub-regional levels (such as location-based services). However, as tests have shown, the quality of the resolution of the RRG database is about +/- 5 percent, i.e. comparing the link lengths of the database with real distances yields an average shift of between + 5 percent or -5 percent. The following Table demonstrates these effects by samples from the inland waterway dataset. The lengths of selected inland waterways of the GIS database (column ‘RRG’) are compared against the official German ELWIS/WESKA classification.
RRG GIS Database contents:General informationGeneral database description Region boundaries, admninistrative boundaries Geography Interaction data and regional data Informationen zur RRG GIS Datenbasis sind nur auf Englisch verfügbar. |
||||||||||||||||||||||||||||||||||||
|
||||||||||||||||||||||||||||||||||||
