Stack from subsets

snap
#1

Hello

I would like to know if it is possible to create a stack with subsets. If so, how can I do it?

thanks in advance

Martha

#2

what data are you referring to?

#3

How does the title relate to your question?

#4

Sorry Marcos and Andreas for the confusing title. I dont remember to put that title.

I have now two subsets and I would like to create a stack to check coherence in order to have a DEM.

Thanks in advance

Martha

#5

please clarify what is your input data (sensor, mode, product level…)

#6

I made subsets from single look complex SLC of sentinel 1B, mode Interferometric Wide Swath Mode (IW)

Thanks in advance

Martha

#7

I see, thank you for clarification.
The only way to reduce the extent for InSAR is the TOPS Split operator at the beginning (followed by Apply Orbit File). Then you can apply Backgeocoding and ESD (only when you have selected more than 1 burst). Use the coregistered stack to create an interferogram and apply TOPS Deburst. Only after debursting you can make a spatial subset.

#8

Thank you Andreas but I was expecting that reducing images with the subset tool would increase the possibility of coherent images for a DEM.

For me, it has been so difficult to get coherence with those big images.

Thanks

Martha

#9

I don’t undestand how the size of the area has an impact on coherence. The back geocoding and ESD operator allow fine tuning of the coregistration.

#10

yes, it was a desperate hope. I have tried many images of sentinel 1b, with high temporal resolution and I can not find images with high coherence to get a DEM.

Do you know if the absolute orbit should be the same for the two images in order to get coherence?

Thanks Andreas for your help

Martha

#11

the absolute orbit cannot be the same, because that would mean two images from the same acquisition date. But the relative orbit must be the same (same track).

Did you see this tutorial: DEM generation with Sentinel-1 - Workflow and challenges

#12

Thanks Andreas for clearing ideas.

Martha