Example:
The sun is 8.5° below the horizon in the image below, and I think the sky should only be this bright when the sun is at like 1° below the horizon.

Another example:
There should be no daylight visible to regular human eyes when the sun is 17° below the horizon in this image; maybe this ought to be how bright the sky is around 8.5° below the horizon instead.

yeah, i had some stuff going on with the atmosphere simulation to extend the "blue hour". however it kinda ruins sunsets, so im removing it. it has already been removed in the unstable development branch, so it should be coming to the main branch sometime soon