Atmospheric Fog Sun Disc Has Wrong Intensity

This behavior has been observed in 4.18.3, 4.19.2, and Main (CL 4048405). Note that adding  BP_Sky_Sphere to the scene and assigning the Directional Light Actor to it will fix the issue.

Per User:

Sun disc directly visible on Atmospheric Fog does not have correct intensity, resulting in absence of bloom and lens flares. Sun specular reflections in the scene have correct intensity. This energy conservation mismatch leads to very odd looking scenarios.

1. In empty level, add Atmospheric Fog and Directional Light.
2. In Directional Light properties, set Atmosphere / Fog Sun Light = True
3. Add PP Volume set to Unbound, enable default Bloom and Lens Flare properties
4. Create a basic sphere mesh with metallic reflective material
5. Compare Lens Flare and Bloom of the Sun's reflection in the sphere material versus looking directly at the Sun Disc.

Result: The Bloom and Lens Flare in the reflection is much more intense than when looking directly at the Sun

Expected: Sun Disc and reflection have same intensity