I have a cartographic project in Greece. The raster data go back in' 50s and '60s. That time the geographic system that was used was HATT (hellenic azimuthial). As a result the most of my raster file use that strange grid. The greek military geography service has published a method for the transformation of the hatt grid data to Greek Grid (2100). This method uses 2nd degree polyonomial function as you can see bellow
Αx and Bx are factors given by GMS
Χi, Yi the coordinates in HATT system and
Ei,Ni the result coordinates in Greek Grid (epsg 2100).
It a problem that i can solve easily in excel but i need to create a custom transformation to use with raster data.
unfortunately CreateCustomGeoTransformation doesn't seem to support a custom equation only the following
Geocentric_Translation, Molodensky, Molodensky_Abridged, Position_Vector, Coordinate_Frame, Molodensky_Badekas, NADCON, HARN, NTV2, Longitude_Rotation, Unit_Change, and Geographic_2D_Offset