I wanted to try the new DEM assisted coregistration which comes with SNAP 3 (I am happy that this function was added !). Unfortunately there is no help document available. How is one supposed to use this tool? Which kind of input is expected (e.g. one terrain corrected image and the slaves are non-terrain corrected)?
The input should be products with precise orbits - not terrain corrected products.
It’s similar to the backgeocoding used for TOPS coregistration. It’s based only on the geometry. In some cases you may want to run cross correlation and warp after it to apply any final adjustment.
If, on the other hand, you looking at something with movement such as a glacier then don’t use the warp and instead use the offset tracking.