Yeah, me too, but the trouble is, when I've got my audio programs running, there's not even that much left!
Now I've had a play around, I think I've isolated the problem to the cloud fractal shader. It just uses the whole greyscale, which means there's black in there. It is affected by the haze, but only noticably at high thickness.
It's a nice enough effect.
1: nothing
2: cloud set as colour function
3: cloud set as luminance function
4: cloud set as lumincnce function (same as before but it looks different, how random) with THICK atmosphere.
M.