I have a set of interpolated raster files derived from a road network. Where QNEAT3 has interpolated between the road lines to make a simple outside edge, the values given in these 'white spaces' are sometimes above the threshold set (600 seconds). I'd like to cull all values above 600 and ideally trim the raster edge to sit within a parish boundary line - see image below.
There seems to be lots of way to remove null values and those below a threshold, but my intent is to remove those above a certain number.
Ultimately I want to merge several overlaid rasters into a single image with cumulative values, and I don't want the interpolated values to distort the picture.
