Ssving DEM - Range Doppler Terrain Correction Operator

I would like to process multiple files using Python script.
One of the processing steps will be to use Range Doppler Terrain Correction.

I wonder if selected DEM will be downloaded only once. or each time when I execute ‘Terrain-Correction’ operator? According to documentation:

Various different types of Digital Elevation models can be used (ACE, GETASSE30, ASTER, SRTM 3Sec GeoTiff).

The SRTM v.4 (3’’ tiles) from the Joint Research Center FTP ( will automatically be downloaded in tiles for the area covered by the image to be orthorectified. The tiles will be downloaded to the folder .snap\AuxData\DEMs\SRTM_DEM\tiff

So I am not sure if files will be removed after processing file.
As I can see ‘saveDEM’ parameter controls whether DEM data will be saved in output file only, not if downloaded DEM will be or not removed.

once you downloaded a DEM for an area it stays in the aux folder until you delete it manually. So you won’t need to download it again when you process data from the same area.

The “save DEM” checkbox additionally writes it in your target product, but it is not required for processing or storage of the DEM.

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