Can someone tell me what the difference is between the "special effects" setting in-game vs "post processing"? It looks like special effects is bloom in the car and post processing is bloom outside with lights. Is that right? Does one require more performance than the other?
All bloom should be under post processing. Special effects is more the amount of smoke and particles, I think.
post processing makes this game look awful imo, completely un-natural bloom on circuit lights, headlights and dashlights.
Hmm. Well, i definitely get a little bit of halo-type bloom on the steering wheel lights with special effects on, so it must have some sort of impact on bloom within the car.
They have no impact. Special effects control particle effects like smoke and water spray, but AFAIK they were disabled so you can't cheat with having better visibility than others. Post FX are post-processing tweaks to the image, which add the halo-bloom effect etc., separate from special effects.