It's all in Cinema 4D and the whole thing is 3D—no photography. The fog volume is just a giant cube of fog in the background with more density and another one with much lower fog density in the foreground.

Also I have two lights: one is a daylight simulator right at sunrise which is allowing the BG fog to glow, and the other one is a giant softbox that is working as my key light. Has a pretty low Kelvin.