Terrain correction Alos Palsar Full polarimetric

Hello, terrain correction does not work correctly since it generates a displaced image 500 meters. It is an Alos Palsar SLC 1.1 image with Full polarimetry, for its process I follow the following procedure: Cal_ML_Spk_Dsk_TC, for the terrain correction I use the DEM STRM30 (external), and it is configured in the following way the processing data:

Any comments to solve this problem? Are the parameters of the process wrong?
thank you very much!!

I noticed that you entered 0,5 in the RMS threshold instead of 0.5. I don’t know if this causes your shift but at least it is one possible error source which can be eliminated.
Did you try Range Doppler Terrain Correction as well?

It is 0.5, thank you for your observation, however in the same way it generates an image displaced between 500 and 1000 meters, same with range doppler terrain correction. Also try to change the parameters of cross correlation, but in doing so it does not process the images and generates a report with errors.

was the data downloaded from a free souce? If so, you could provide me the image date and region and I can try it myself.

Thank you, they are data purchased from Alaska Satellite Facility several years ago, I do not know if they are free today. The image is ALPSRP203646400-P1.1__A, November 20, 2009 3:48:00. is from the region of Araucania, Chile.

thaks again!

works fine for me. I skipped the speckle filtering for a higher number of looks but I doubt that this made any difference.

ok, great !!, what dem used?

SRTM 1ArcSec 30m in the Range Doppler Terrain Correction.

I followed the same procedure and this is my result, maintains a notorious displacement regarding the result that you obtained

Problem solved, download the data portal product again and process the product again and …, it worked !, for some reason the data that I had saved was missing information.

Now the problem is that it generates a distortion as line in several parts of the image.

thank!!

I also had that line, probably a processing error of the raw data :expressionless:

ABraun, thank you for your help, I managed to process the images and move forward in my work. If you ever travel to Chile you can visit me, I will cook a good barbecue for you …

Thank you!!:sunglasses:

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