I have two DEMs, one (DEM1) containing more details than the other (DEM2). I warped DEM1 (warp) to DEM2 (base) to make the coordinate system match (correcting in x and y direction). Now the coordinates in the two DEMs matches but the elevations divert unequally over the DEM. I want to make DEM1 to match DEM2 in the z direction (elevation). I've tried using Rigorous Orthorectification but it doesn't seems to be the solutions as interior and exterior orientation for the 'Build RPC' is unknown. Is it possible to do this without any additional modules? Or can it be done via DEM Extraction Module?