Envisat-1 ASAR Coregistration Error "-1"

Hi All!
I am trying to perform the Coregistation Envisat-1 ASAR Image Mode Single-Look Complex (ASA_IMS_1P).
Here are the steps I’ve done so far:

  1. Radar -> Apply Orbit File
  2. Radar -> Coregistration -> Coregistation

I have error “-1”. What is error? Can you please help me with this matter?

P.S. I did the same steps but with the first five images, and everything went well.

have you had a look at all processed files (after applying the orbit files) if the images were created correctly?

Yes, I had look all the images after Apply orbit… All 9 images .dim i see (i_vv, q_vv, intensity_vv).

and does the intensity band look alright?
Maybe you can identify the product which causes the error by leaving out all but one at a time.

Yes, look alright. Below is a group of files with Apply orbit, no errors.

InSAR Stack Information:

InSAR Stack baselines:

But in new file Full_Stack bands not show.

Which option did you chose for the Offset Method: ORBIT or GEOLOCATION?

Selected ORBIT.

hm, that’s also ok.

Did you try chosing another image as master?

No, only tried make Coregistration first 5 images and this process well done.

Hello there. What is the solution of this problem? i might happen to have the same problem, but I can’t visualizze either any of the results: i_vv, q_vv, intenstiy_vv . everything is empty.

Some thoughts:

  • Have you checked both input products for possible systematic errors?
  • Are both inputs from the same track?
  • What is the perpendicular baseline of the data? (InSAR Stack Overview)
  • Were orbit files applied prior to the coregistration?

1.I haven’t checked the input data, becouse I used some other data and the process end well.
2. everything is from the same track.
3. Which one of the perpendicular baseline should I say? the master baseline is 0, and the other changes
4. I didn’t apply any orbit files because my products are from COSMO SkyMed

the one between the master and the slave, so the larger one, especially for the pair which does not work.

the larger one is - 1731 m.
But most of them have great values of perpenicular baseline, mostly over 400 m

I actually don’t know which pair does not work. every product result after the coregistration is empty.

1700 is quite large, there can be extensive offsets between both images. You can try to increase the number of GCPs (8000).

Please have a look at the InSAR Stack tool (under View > Tool Windows > Radar) which lists all remaining GCPs, especially for the products which failed.

how can I increase the number of GPCs?
for the list of the remaining GCP’s I have to look at the Coregistration residuals, right? there is an empty page under this tab.
I noticed that under the tab of Baseline, in the coherence column, half of the slaves have a 0.01 coherence value. Is that a problem maybe?

nevermind, that was a stupid question. I’m re-starting the process again with a number of GCP of 8000

yes, a larger perpendicular baseline probably requires more GCPs.

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