I’ve been working on a day/night cycle and stumbled upon a strange problem with my fog.
Whenever the suns rotation is Roll = 29.334326 °, pitch: 0.865016 °, Yaw: -41.106083 °. Below is an image showing the strange red color that appears at this rotation:
If it’s Atmospheric Fog, that redness is depicting rayleigh/mie scattering, where parts of the spectrum are being filtered by particulates in the atmosphere.
If it’s Exponential Fog, and your Directional Light Source has ‘Atmosphere Sun Light’ checked - it could be your Directional Inscattering Colour.