NaN values occurs when using BandMaths in Graph Builder

Hi

I’m currently building a graph in snap for batch processing Sentinel-1 images. The purpose of the graph is to remove thermal noise, perform radiometric calibration, filter speckle, and scale each image to the same dynamic range, i.e., between 0 and 255. However, when I “clip” the values below 0 and above 255 after scaling, NaN values occurs. I don’t understand why this happens. Can anyone explain this? Any suggestions on how to fix this or alternatives on how to achieve the same scaling in a different manner is appreciated. The graph is added below.

Remark: The NaN values does not occur when I use the clipping operation (see BandMaths(3) and BandMaths(4) in the xml file) directly in the SNAP GUI.

S1processing_bandmaths.xml (6.8 KB)

Regards,
Vebjørn

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