Hi,
I am on Paraview 6.0.1 and when I load a HDRI and enable it as Environment with OSPRay, the scene is very dark and the background HDRI is also very dark.
Here’s a free HDRI that I used:
And this is what it looks like in Paraview with OPSRay on:
When I use PBR with the Skybox instead, the background image looks better, although it is still a bit too dark.
Dark is not the best word because the colours are shifted, noon is actually turned into a sunset.