Reply To: Grime, Grunge, Dirt is Misbehaving
Although it was a mistake on my part setting the AO that high, it would be good to understand the process of AO in Eevee as it was a really weird result.
AO in Cycles is really solid because it’s calculated from the actual distance between two surfaces, and that info comes basically for free during path tracing. Eevee, on the other hand, doesn’t have path tracing so it tries to approximate the AO based on the distance between surfaces and the normals according to the camera/viewport.
By setting the AO distance so high, it’s essentially telling Eevee that an object should be occluded by everything within 80 meters of it. The reason the camera’s closeness had an effect is that screen space AO can’t take anything behind or outside of the camera into account, so the closer something was to the camera the fewer things Eevee would see around it to occlude it. Check out this gif and notice how, the closer something is to the camera, the less an engine like Eevee will naturally see around it:
Hope that helps!