This looks like lightmap compression. Try to turn off “Compress Lightmaps” in World Settings and you should get clean result, but remember you usually don’t want to turn off compression for runtime projects like VR, games or whatever when you are “Playing” it. It’s memory heavy and can couse some problems with optimization and texture streaming if it’s bigger scene. For taking screenshots or video it’s OK.
Go to the folder where is your UE4 installed and open “Engine/Config/BaseLightmass.ini”. At the bottom you will find “DevOptions.GPULightmass” section and set desired NumPrimary and NumSecondary GI Samples. 32/16 is Medium Quality, 64/16 Ultra High, 128/32 Extreme.
[USER=“24021”]pax invictus[/USER] Thanks for updating to 4.24… You are the king 