DEM - can it be shifted down in height?

[BenW22]

Hi All,

I created a project from UAV images (Zenmuse P1). Several GCP's were used as control. The data processed very well with very low RMS, Total Errors and good Check point results. Every check mark under 0.03m for Easting, Northing and Height.

I then created a 3d model, tiled model, DEM and ortho.

It was after everything was created when i found out the GCP values have an absolute error of 0.04m in height from a bad benchmark value. The values I used need to be lowered by 0.04m. I went through the GCP values in the Reference pane and lowered the source values by 0.04m in height and ran the "update transform" button, not knowing what would happen to my 3dmodel, tiled model and DEM.

I was very pleasantly surprised to find that my 3d model and tiled model updated perfectly! That is, there was a total shift down in height of 0.04m across the whole 3d model and Tiled model. This is exactly what i needed.

But when I look at the DEM, it did not shift at all. So I then went to Tools/ DEM/ Transform DEM and ran that. But no shift happened.

My question is - does anyone know how I can shift the DEM 0.04m down in height. Or do I have to delete the DEM and run "Build DEM" and create a new one from scratch?

Any help appreciated
Ben

[Costas]

I do not think you can transform DEM in Z value.

The only solution is to re-build the DEM or exported it as is and do the transformation in a GIS program (ArcGIS, QGis etc)

[olihar]

You can easily do this in QGIS.