I'm attaching a render of a scene I'm working on. I'm rendering at quite high settings, but still getting patches on the wall. Apart from the cove lights (made using vraylightmaterial), there is only one light in the scene - a vray plane just in front of the window. Increasing its subdivs from 8 to 24 helped a lot, but didn't completely remove the patches.
So what can I do to improve this render?