When I calibrate Sentinel1 SLC SM data (e.g. S1A_S1_SLC__1SDH_20190423T121118_20190423T121148_026917_03072D_C5F5) to sigma0 (both complex or not) the result is an image with all zeros (tested for geotiff + beam).
What am I doing wrong?
Especially since the same process works for terraSar-X data.
(I’m using SNAP 7.0 on Windows+Linux)
To understand more, what were the steps you applying? reaching to sigma0,
Second thing why you don’t download GRD, in case your goal is to calibrate to sigma0
I just used in the menu: Radar>Radiometric>Calibrate (Creating a graph with read>calibrate>write does the same).
We use the SLC data since we need the complex valued information.
I’ll test it late today , and comeback to you ,
The ThermalNoiseRemoval throws a NullPointer Exception.
Log:
SEVERE [org.esa.snap.rcp.SnapApp]: A problem occurred during the target product processing.
Type: OperatorException
Message: java.lang.NullPointerException
org.esa.snap.core.gpf.OperatorException: java.lang.NullPointerException
at org.esa.s1tbx.calibration.gpf.Sentinel1RemoveThermalNoiseOp.computeTile(Sentinel1RemoveThermalNoiseOp.java:623)
at org.esa.snap.core.gpf.internal.OperatorImage.computeRect(OperatorImage.java:80)
at javax.media.jai.SourcelessOpImage.computeTile(SourcelessOpImage.java:137)
at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:904)
Caused: org.esa.snap.core.gpf.OperatorException: java.lang.NullPointerException
at org.esa.snap.core.gpf.internal.OperatorExecutor$GPFImagingListener.errorOccurred(OperatorExecutor.java:376)
at com.sun.media.jai.util.SunTileScheduler.sendExceptionToListener(SunTileScheduler.java:1646)
at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:921)
at javax.media.jai.OpImage.getTile(OpImage.java:1129)
at javax.media.jai.PlanarImage.getData(PlanarImage.java:2085)
at com.bc.ceres.glevel.MultiLevelImage.getData(MultiLevelImage.java:64)
at org.esa.snap.core.gpf.internal.OperatorContext.getSourceTile(OperatorContext.java:407)
at org.esa.snap.core.gpf.internal.OperatorContext.getSourceTile(OperatorContext.java:393)
at org.esa.snap.core.gpf.internal.OperatorImage.computeRect(OperatorImage.java:73)
at javax.media.jai.SourcelessOpImage.computeTile(SourcelessOpImage.java:137)
at com.sun.media.jai.util.SunTileScheduler.scheduleTile(SunTileScheduler.java:904)
at javax.media.jai.OpImage.getTile(OpImage.java:1129)
at com.sun.media.jai.util.RequestJob.compute(SunTileScheduler.java:247)
[catch] at com.sun.media.jai.util.WorkerThread.run(SunTileScheduler.java:468)
This problem is coming back to your machine facilities, check up the RAM and also check up this post,
Try up to make small subset of the image and check up, whether it works or not?
I have increased the memory usage to -J-Xmx32G, tried the use fileCase in readers option and subsets as small as 100x100px, still NullPointer Exception 
Please try with an IW SLC and see i the problem persists. Your system certainly has enough RAM for the job so perhaps it’s something related to the SM-product.
Sorry, I cannot try that at the moment.
But after applying the orbit files, calibration seems to work as intended.
Guess thermal noise removal has to wait.