Importing RTC S-1 into QGIS

I’m trying to import an RTC Sentinel-1 image into QGIS. When I am adding the raster into the QGIS interface, I am using the .img extension (in this case Gamma0_VV). The problem is, those files, once imported into QGIS seem off. Keep in mind, I’m new to SAR The reason I believe they are off, is because when I import the same image into ArcMap, I get different numbers. I am also able to run the Raster Calculator in ArcMAP (for dB conversion, amp), but not in QGIS. I get a blank page, and no data values (NaN).

<img src="/uploads/default/original/2X/5/51c5b95a544612951b2f42e37ee7dacd25290ffa.png" width="546 height=“500”>

When I try to export the image (very large file size) it doesn’t allow me to export as a GeoTIFF. To solve this, I created a subset and imported that into QGIS. I still am unable to use the Raster Calculator and the numbers are still off.

Do you know if this is becuase GDAL doesn’t support these kinds of files? Or is my sample image simply too large to import correctly? Any help is greatly appreciated!

The different numbers could be due to image stretching. QGIS visually ‘cuts off’ the upper and lower 2.5% of each image for better contrasts while ArcMap uses a different grey value scaling.

Have a look in the raster metadata in both programs and you will see that they are the same regarding minimum, mean and maximum values.

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