You may define geodetic datum transformations using the Canadian NTv2 transformation method. The Canadian NTv2 defines an accurate transformation from NAD 27 to NAD 83 for Canada. The shift values for geographic areas are stored in a single grid file, representing latitude and longitude shifts (named with the extension .gsb). GeoCalc uses grid files in a format published and provided by the Canadian Government.
The "CanadianNTV2" DatumShift has the following Parameters:
|
Parameter Name |
Parameter String |
Units |
|
Canadian Transformation File |
cantrans_file |
String |
Certain NTv2 Datum Transforms' grid files are provided by third-party authorities that allow the use of these files through a Creative Commons license:
The bwta2017.gsb grid is licensed under the https://www.govdata.de/dl-de/by-2-0 "Data licence Germany – attribution – version 2.0" license.
The seta2016.gsb grid is licensed from LVGL Saarland (https://www.saarland.de/) under the Creative Commons Attribution 4.0 license (https://creativecommons.org/licenses/by/4.0/)