Fantastic !
QuoteBy default there isn't very much contrast in a powerfractal. So if you set roughness to 0 and keep contrast at ~1 then you might not get the result you expect because the powerfractal's colors are not "bright" enough. If you increase the contrast to around 4 for example then you'll see that the coverage increases a lot and more accordingly to your blending powerfractal.
Above advice is what did the job, i played arround with the contrast in the power fractal (blending) shader and now the cumulus layer looks much more like the power fractal.
QuoteA color unclamped colour adjust with black point to ~0.1 and gamma reduced to <0.5 may also aid in reducing roughness.
This had a small effect on noise
There still is some noise, but at least I now know in which direction to go now.
QuoteYou said the cumulus coverage is -0.3? Or the color offset in the density fractal is -0.3?
I changed the cumulus coverage and the power fractal's color offset now, to fit the new settings.
I found that i can control the clumping amount within the cloud by changing the lead-in scale of the density shader
Any way, thank you for your advice, it was really helpful