oh no! it needs more than 8GB. Bye bye master, bye bye thesis, bye bye better job
Well I found a computer able to process my data. I have done all the steps on the manual and I am one step away from Sanphu Export. My problem is that I don’t want the whole image to processed, I need just the island. I tried making a subset but I couldn’t. What can I do to isolate my area?
You can largely reduce the amount of data already in the TOPS coregistration step as described here: The Order of DEM Creating Steps
Thanks a lot for the tip! It worked perfectly. I would like to ask something else.
- I finished all the steps up to filtering for a pair o SLC images. Now I will export the result to Snaphu so i can have the information for the land deformation, is that right?
- I have 20 pairs of images. I have to do all the steps for each pair. My question is: How I combine all these results to have the final result?
If you already removed the topographic part of the phaae, you can proceed with the unwrapping.
For longer time-series it is good to pair images with short temporal baselines, geocode the results and then stack them in the end.
Have a look here. Some things were different back then but the analysis of results in the last slides is well done:
I indeed removed the topographic phase. You think it is better to use NEST than Snaphu?
no, the tutorial is just from a time then SNAP was called NEST. You can proceed with the export and import without all the complicated steps in the tutorial and directly terrain correct the displacement map as described in the last part of the slides.
Should I export the Histogram Phase after applying the filters?
The Histogram of Phase for the pair i am processing is that. The perpendicular baseline is 103,29m. I am not sure if this is ok. Can you please help me?
manually adjust the min / max values to -5 and +5, for example to have more detail in this area.
Outliers in your data strech the histogram over an unnecessary large range.
It doesn’t change at all. Should I export the Histogram after the phase filtering?
you can also look at the raster statistics
How does the image look like?
the range is reasonable, but the high amount of 0 is suspicious. Could be the value at the border of the image - please show us the image of the interferogram.
I think that happens due to the fact it is an island and the water probably has 0 range
yes, as I expected. However, I don’t see any fringes in the image. Do you have coherence in your image?
that looks good actually.
I produced all the displacement maps for each phase. Now I want to so that on a map. How do I do this? Should I export my map to ArcGIS? Is there a possibility to combine all the separate displacement maps to one?
what do you mean with “do that on a map”? If you terrain correct your results they are geocoded.
About the combination of different displacement results:
If all of your images are of same imaging geometry you can also proceed like described in the last slides of this tutorial: https://eo-college.org/resources/insar_deformation/