Today I setup a train interior with lighting per physical sky. The lighting looks very nice, but the reflections of the horrible bright sun cause bright noise at some places, so I can forget to use the physical sky and must look for an other solution.
It’s a pity, that know problems are alive after months and I run in it again, - now during a big project.
Also the problem and a solution is well known from CG:
Interesting for me, if I set the sun intensity at 0.001 and the sky intensity at 1000, than I get a physical sky without sun light, but the bright reflections of the sun are still alive …
Today I’m working on a water yacht scene. The sky is an important part of water scene, because it’s very dominant. I need a clean sky and the physical sky could be a good, easy solution, but I must workaround the bright sun and can’t use the Vray sky. That’s frustrating, so much time is needed. If I would use the Vray sky, than interreflection between yacht and water would cause very long render times or noise …
… here an example that show, that i’m not talking about a little problem only - the scene is perfect looking in a HDRI environment, but the sun/sky environment is a pain. I stopped the test, because the calculation was so slow.
I hope, the example show, how problematic the physical sky is and I can catch some interest. The problem is reported march 2007 first time.
Thank you. Often I need the HDRI output and like my HDRI env renderings show me, this total bright sun isn’t needed for a good looking image, so I’m not happy, that I should invest much time for sampling calculations. The “physical correct” Maxwell dosn’t use a high sun intensity like this … and it works.
For now my goal is to avoid the sky allways. The risk, to render a new view, a detail of a scene, and the sun could cause a strong noice, is to high. Tight deadline dosn’t allow an extra risks.
