I have successfully created a DEM using a pair of COMO SKYMed image and SARScape. I used the "Interferogram to Phase Unwrapping" in the "Interferometry" menu (followed by "refinement and reflattening" and "Phase to height conversion"). I have done this for full image scenes. However, I would like to attempt a higher resolution for a small area (the higher resolution requires too much memory for the entire scene). To create the subset, I used the SARScape Tool "Sample Selection" and followed the same procedures I did before to create the DEM. However, the "Interferogram to Phase Unwrapping" creates an unusable output - it does not appear to be an interferogram at all. Does anyone have any insight to this problem? What the "Sample Selection" is doing? Or how one might create a subset with a different procedure? Thank you.