we are looking for a way to easily transform from wgs84 ellipsoidal to umt9 cgvd28 and back again.
we work almost all our jobs in utm cgvd28(ht2). unfortunately the uav lidar setup we have needs a base coordinate in wgs84 ellipsoidal. so we first need to transform our base to this. then the point cloud out put is also in wgs84 ellipsoidal. we would like to bring this into tbc and then transform everything back to utm9 cgvd28.
we understand the change coordinate system routine in tbc. and mostly the coordinate system manager. the issue seems to be that any transformation we attempt in the horizontal also seems to affect the vertical. or this is what we think is happening. we can test the results by comparing the same transformation done in the lidar manufacturer s software and qgis. in tbc we see a 10cm vertical difference in the point cloud.
can anyone suggest the correct transformation parameters needed to do this? or any settings we might be missing? why can t we use coordinate system 3156 in the coordinate system manager as this is a common definition. or is there a way to load it. or force the transformation to not alter our vertical during the horizontal transform.
thanks for any input that would get us in the right direction. we can process using the lidar software but it means loading to the cloud and then downloading again which is a waste of time for nothing.