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GIS Tools
Enter the latitude and longitude (in decimal degrees) of the point you want to transform:
The Albers Conic Equal-Area Projection is used for the presentation of thematic data continuously across the continent. Its equal area properties make it suitable for accurate area calculations.
This transformation is based upon the Geocentric Datum of Australia (GDA).
Albers to Geographicals Transformation
Geographicals to Albers Transformation
Script:
The spatial data transformation is performed by a Perl script which has parameters passed to it via the forms interface. The Albers to Geographicals transformation also makes use of C executables to compute arcsin and arctan functions not available in Perl.
Mathematics:
The transformation algorithm makes use of the equations published in the United States Geological Survey manual - Map Projections Used by the U.S. Geological Survey Bulletin 1532 The transformation has been modified to use the Geocentric Datum of Australia (GDA) as its reference.
Spatial Accuracy:
Tests conducted reveal the Geog to Albers coordinate transformation as being on average accurate to approx. 10 cm on the ground. The Albers to Geog transformation is accurate to less than 20 metres (nominal) on the ground for computed latitude, and with considerably improved accuracy (usually less than a metre (nominal)) for longitude. The latitude accuracy should hopefully be improved with a new algorithm which will be implemented soon.
Future Enhancements:
To cater for Geographicals in both Decimal Degrees (DD) and also Degrees, Minutes and Seconds (DMS). Also an improved latitude computing algorithm and the possibility to cater for transformations based on other spheroids.
For further information contact:
Scientific Coordinator
Spatial Science
info@erin.gov.au