3sec DEM Unreachable for all SNAP versions?

Microwave Toolbox
#1

Hello,

For the past few years 3sec dems (with sentinel data) has provided good consistent results, but as of recently I couldn’t get coregistration to work with 3sec dems, so I switched to 1sec dems and now my results are hit or miss, with some data looking decorrelated. The first image below is of a successful run of my process, but the follow up image is of an interval one month earlier, and the near-uniform lines I’m seeing I’m being told is an error with the data, or possibly an error with the process concerning hardware and space/storage issues. Is there possibly a space/hardware/equipment issue happening now that I’m trying to use the 1sec dems for processing? Or could it be the type of dems themselves?

I’m currently working out of Snap v6, what are the computer processing requirements for v8? A coworker tried using v8 but said “Snap is unable to apply any orbit files to the data processing” and his work around was to downgrade to v6.

Thank you all for your time and help!

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#2

That orbit files issue is very common these days maybe the website is down from which snap downloads in backend. You can manually download them and add to the orbit files folder.

For good interferometry results what I believe the following should be minimum specs.

  1. SSD or NVME drive. (Hardisks not preferred)
  2. 16 GB RAM minimum
  3. 8 Cores processor clocked above 3.0 GHz
#3

Make sure to update SNAP to latest version. My backgeoding process wasn’t running after updating it to latest version started working.

#4

Sometimes a clean uninstallation including all user data helps to get rid old configurations.
What you describe sounds like the software was updates, but the settings remained. Especially when you switch between versions.

1 Like
#5

SNAP6 is unsupported, please switch to version 8. You’ll have to install module updates so the orbit file locations are updated too.