Dear all,
I have also downloaded the images from ASF and this is what I have got after processing them (no deskewing applied)
From right to left: 1)coherence ; 2) Pure interferogram (Ref phase and Topo included) 3) Interferogram after Ref Phase removal (Flat-Earth removed) and; 4) Interferogram after Ellipsoid and Topo Phase removal.
There is almost no difference between 3 and 4, that could be due to low topography variation as it is a flat area (delta)
Hence, these diagonal fringes either:
- are due to wrong orbit informaiton
- wrong ellipsoid removal
I have always understood that ALOS-1 had good orbit information and it was not needed to do any orbit modification and hence I would say that SNAP does something weird during the ellipoid removal when using ALOS-1 PALSAR data. Can any of you check this out @lveci or @marpet?
It could be also that in this particular image pair anything else happened…
Just wait for @EJFielding results to understand whether this is a software-related effect . I look forward to it.