I'm trying to save big ortophoto image (34k x 28k px) with overlayed vector contour layer with difference blending mode in order to see contours on every terrain clearly. See an example below:
When I try to save whole image matching original 1 m resolution using Export map to image or Map composer QGIS always crashes. I achieved this by exporting 12 atlas tiles and merging again later. Is there some more straightforward way of doing it?