PFF problem found. I forgot to multiply the term that currently was called Rp with Rs. Silly mistake. Now I get something like this
which looks very plausible to me. I’ll edit in better details later.
Shader:
Blend file:
https://www.dropbox.com/s/hue7ozz0mz3783n/Complex%20IoR%202.blend?dl=0
Overexposed (to show off the deep reflections)
Not as bright
RS:
RP:
R:
Another sign that this is correct now, besides these much better looking images:
It no longer takes forever to render at roughness 0. Previously it would take insane amounts without roughness. Presumably that’s because it didn’t conserve energy.
Also fixed the rusty Suzanne file (same file as before, just linking it again so you don’t have to dive for it):
Blend:
https://www.dropbox.com/s/h3tduu9wc3ao731/Suzanne%20Quick%20Spectral%20Test.blend?dl=0
shiny version:
rougher version:
(Note: these are denoised as there were quite a few fireflies especially in the siny version)
And finally, I did a torus shaped “furnace” of gold:
