Hi
I’m trying to replicate some of my old procedural materials to a new blender version and I hit a snag.
I have this grunge texture created back in 3.6 using Musgrave texture. When I opened it in 4.1 blender was kind enough to convert the Musgrave nodes to new Noise ones, but not perfectly. There is lack of fidelity in 4.1 result.
How it looks in 3.6:
How it looks in 4.1:
The setup is qite simple and the procedural noise itself gives identical result as far as I can tell:
3.6 setup:
4.1 setup:
The difference seem to come from the last Overlay node:
3.6:
4.1:
Clearly the 3.6 version provides more details as if the 4.1 is somehow clamped. I have suspicion it’s because the way the old Musgrave worked (I think it could go outside of the 0-1 value range or something, I don’t know).
If I play with the clamping tickboxes I can eventually achieve same result in 3.6 as 4.1 does, but that’s the opposite of the goal.
I couldn’t find a way to get the details back in 4.1. Does anybody know how to resolve that?
I’ve attached the sample files if anyone would like to play around.
Noise 3.6.blend (2.6 MB)
Noise 4.1.blend (1.2 MB)
Thanks
oook, now that I spent all the time writing this down, taking screenshots and asking on the forum, obviously it was time to figure it out in next few mins, just as Murphys laws dictate 
So in case some is interested:
The trick was indeed in the value range. All I did was to take the White value from the Color ramp and bring its value down a bit. To about 0.1 instead of pure white.
With this, the in 4.1 was finally nearly identical to the 3.6 one. Jobs done 
2 Likes
Have you tried toggling the normalize checkbox? It toggles between the noise values being mapped to -1 to 1 range and 0 to 1 range. Since musgrave was merged into the noise node, the normalization could be what makes the difference.
This could even be a bug since if the old musgrave was in 0-1 range, the if the automatic conversion, which converts from musgrave to new noise doesn’t automatically turn on the normalize checkbox, the results would be same. With automatic conversion from deprecated features, the results should be same.
Thank for the insight. Oddly enough, the normalize checkboxes make it even worse. It completely changes the the texture coming out of the Noise node (obviously), washing away most of the details. There might be a way to get around it, maybe feed it to more color ramp/map range/math nodes etc. but that seems like unnecessary complication at this point.