I have two similar rasters of the Mount Vesuvius and surroundings: one spans 20 kilometers, and the other one 50 kilometers. The two rasters are overlapping:
What I would like to do is to create a new raster file which will show the difference in elevation between these two rasters. I tried using the Raster calculator with the following expression:
"vesuvius_radius_20KM@1" - "vesuvius_radius_50KM@1"
But for some reason it does not work. After I press OK, all I get is some sort of black raster file which does not have any kind of elevation data in it, nor it has any number of pixels:
What am I doing wrong, and how can I create a raster file which will show the difference between the upper mentioned two raster files?
Here are those two raster files: