Radiometric Terrain Flattening - Hot solve low DEM resolution?

[ABraun]

glad it helped, but the solution was already given here

[Terrain-Flattening] The DEM resolution is lower than that of the source image

Use of SRTM 1arcsec DEM with Sentinel-1 GRDH images was possible with SNAP 3.0, and results were acceptable. SNAP/S1TBX 5.0.x now reports: The DEM resolution is lower than that of the source image. Please multilook the source image or use higher resolution DEM (e.g. SRTM 1Sec HGT) to make sure the DEM resolution is higher than that of the source image. A possible workaround may be to up sample the DEM to 0.5 arcsec. However, we may revert to SNAP 3.0 since Terrain-Flattening of Sentinel-1 GRD…

Effect of Multilooking on Terrain Flattening

You can skip the multi looking by changing the re-grid option in the terrain flattening module. A comparison of the result with and without multi looking would be interesting.

Terrain flattening co-registered images

Disable the re-grid option and you can flatten without multi-looking.