Hello everyone,
I am new to SNAP so was wondering if someone might be able to help me 
I am using SNAP to prep my S-1 datasets before ingestion into MintPy for SBAS time series analysis.
I downloaded two S-1 SLC datasets and processed them in SNAP using the following operators:
Split → Orb → Stack → ESD
I used default settings for ESD. For stack I used 30m Copernicus GLO DEM and BSinc_21_point for interpolation.
I wanted to check accuracy of the coregistration but it seems the ESD Measure and Coregistration residuals are not available (using SNAP 12 on Mac M1 Silicon).
I loaded both Intensity bands from the stacked dataset and tiled vertically. When I move the cursor around one band, it also moves in the other displayed band, but there is visible offset of around 25 pixels. This is after ESD has been applied. Maybe I am doing this wrong? If I use Layer Manager and load both intensity bands, and use the swipe feature, then the pixels seem perfectly aligned both before and after using ESD operator.
I have attached a screenshot that should show what I mean.
Any advice / comments are appreciated. Many thanks in advance.
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Please can some kind person help me?
I am also attaching the RGB representation of the reference and secondary products. I have sent the master intensity bands to Red and Green and the slave intensity band to Blue. The result seems reasonable to me. Most of the image displays as salt and pepper but areas of low coherence representing wetlands show as blue. I am guessing these blue areas are areas of decorrelation. Border of water and land seem clear and sharp. Is this correct?
I am still not sure though why I am getting what looks like misalignment of pixels in my original post, or is this not an accurate way to determine coregistration quality?
Coherence band also attached.
Many thanks for any guidance you might be able to give.
Can anyone help? I can’t move forward until I am sure that the coregistration has worked. If anyone has any experience in this and is able to comment, I would greatly appreciate it. Thank you for your time if you have read this. Have a great day!
I need help, when i do the coregistration and after deburst i get a uniform coloured phase ( like just violet) i am new to snaps but i need some serious help for a project.
I would say that based on the high-looking coherence, the co-registration quality is high or superb.
Thank you for your reply @mengdahl. Is there a better way to determine the co-registration quality? I am just wondering why if I open up both intensity bands and tile vertically and move my cursor around, they are not aligned… perhaps this is not a documented approach to check the operator? If I layer both bands and use swipe there seems to be very good alignment.
