Global Mapper v25.0

Feather pond inside DEM

stihl
stihl Global Mapper UserTrusted User
edited February 2015 in Elevation Data
Hi,


I have an interpolated DEM of a terrain. In this terrain there are several small ponds. The water was filtered out of the DEM and the holes were interpolated.

Besides the DEM I also have bathymetric data of the elevations in the ponds.

There's a height difference between the two datasets of roughly 1 meter.
I can't feather the bathymetric data because there's not enough overlapping areas between the two sets.

My idea was to let GlobalMapper make a polygon around the bathymetric data which I can then use to make a negative buffer of 20 meters. And then crop the entire DEM to all those polygons. So I'm left with a DEM that has holes where the ponds are but still has a strip left of 20 meters inside the ponds that I can use to feather the bathymetric data so there's a clean transition..

However. I can't figure out how to tell GlobalMapper to feather *INSIDE* an area feature. It will only feather the data outside and not what's within the polygon.


Many thanks.