I am trying the subset an area from Sentinel 1 GRD zip file to execute Offset_Tracking using the following graph builder and WKT coordinates. Study region looks correct in the preview (the little map they provide with a box), but the output always deviates from the correct area. If I do the same steps using GUI, the output is aligning correctly. If anyone has any advice, I would greatly appreciate it!
some shifts occur because the subset is applied to the data in range geometry (not geocoded). If you want to subset exactly the area defined by the WKT you have to terrain correct first. But this involves resampling of the data which potentially affects your offset tracking.
Is it an option to shift the WKT geometry towards East?
Thanks, ABraun. After I shift WKT towards East, I find that the selected area by the WKT is right in the output, but the coordinate is wrong. Although their coordinate system is WGS84, there are some offsets between the output and shp like the picture I upload.
I think so, yes. Although I am still wondering where this error comes from because subseting from GPT has been working fine for years.
Let’s hope the issue will be tackled soon.
my question is, why is the subset in my case located at the correct place while in your cases there is some shift introduced?
Maybe the subset operator called from GPT somehow messes up the tie-point-grids. @lveci is this possible?