For the last few year I have been using digital elevation models (DEM) derived from LiDAR data as part of our initial site planning. The files are provided by the state and are exported from AcrGIS Desktop in Grid coordinate. When we bring them into Civil 3D, it does not transform it to ground coordinate if a scale factor is provided. I believe this is due impart to Civil 3D does not understand they are not ground coordinate. We use the DEM primarily for preliminary layout and then follow up with a ground survey. The problem comes to light when we import our field survey and DEM does not match up if I apply a scale factor in the drawing transformation settings. I know there are other issues with the survey grid to ground conversion but that is another topic for another day.
Autodesk needs to provide a way for users to tell Civil 3D when importing a DEM file what coordinate format the file is in.
