No, it should be the "Lumen diffuse Color Boost". I've set it to 4 or 5.
It boosts the diffuse lighting and local lights, such as lamps of all sorts.
I'm not sure if that what makes the changes real time or not, but I've also put the "Automatically Apply Configuration" to ON and with the game on Fullscreen Borderless and the Ultra + Manager on the second screen, I can see real time the changes to each setting + the performance hit. I wouldn't recommend just max everything, as it kills performance to silly levels - you get much better performance via path tracing in other games.
Mindbogglingly, they thought having dark rooms where you see nothing, but the NPCs see you it's ok. Or that NPCs can spot you via tall / dense vegetation and accurately open fire... and add more grass with the new update!
Anyway, I've added some other mods to sell broken guns, repair cheaply I think, find a lot more ammo on NPCs and stashes (plus valuable stuff, not just "nothingness"), modded the ballistics so they're more in line with the actual performance of such guns in real life (no more a pistol doing more damage than an assault rifle), reduce the life pool of monsters and NPCs from vanilla ridiculous levels, higher jumps and lower fall dmg plus longer sprints!
Overall, it moves the difficulty towards what matters > exploration and proper approach of a gun fight. The game changes a lot and feels a lot more fun to play than doing stupid management of an artificially scarce economy that normally would make the zone uninhabitable.
