Eureka! I found the document explaining surface settings in Iray!
Tako Yakida
Posts: 548
If you ever wondered what some of the more obscure settings did in Iray shaders, check this out:
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thank you!
pointer appreciated and saved!
--ms
Tako that info has been there since DS/Iray came out. ;) Still not quite complete but it helped me no end when I was learning Iray.
You can also check the Nvidia docs, although some settings may be different for DS.
http://raytracing-docs.nvidia.com/iray/manual/index.html#preface#1001
That page does help me for some things, but for others e.g. controlling glossiness, there's a certain amount of circular definitions when what I need is a description of how to use the various parameters. I think I'm following instructions in setting up a slightly shiny material, but it persists in gleaming like a showroom-ready car.
And after all this time, I still don't know what the units are in the Bump setting. Centimetres, millimetres, nanofurlongs?
If the units are the same as the 3dl shader then depth should be centimeters which I do believe they are.
as for gloss. My advice when working in Iray use the Metal/Rough shader. Spec/Gloss is way too fiddly for no real benefit.
Ok I have some time, so what type of surface is it and post your settings and let see if I can shine some light on the situation. Once you grasp it, it should fall into place.
It's just the glossy parameters in general, when I'm trying to reverse engineer a converted Poser or 3Delight material. Chief among the usual suspects is Glossy Layered Weight — I know that it controls the glossiness properties, because the doc page says so. What I don't know (because the doc page doesn't say so) is how it controls them; I can copy parameter settings from some other surface that renders the way I want it, but it doesn't seem to matter what value I plug into Glossy Layered Weight, it renders super shiny or super dull with not a lot in between. I think at several points I was getting the shinies at near-zero GLW values. If that's the way it's supposed to work, the doc page ought to explain it better.
@mindsong You're welcome! :D
@Szark I am sure but for some reason I never hit it before. I was actually googling "anisotropy rotations" when the page popped up unexpectedly in the search results. Hurray for Google. :-/
@maclean Thank you for the additional data! The more the merrier!
@SpottedKitty I feel your pain. If I understood all the settings better I would rewrite the page and send it to them for publication. Hopefully Szark has some good advice along the lines of what you are experiencing!
OK can I see your settings please so I can see what the problem is