Important sampling problem HDRI lighting C4D-demo

[HandsomeRob]

Hey.

I have been trying out the demo-version for Cinema 4D and I really like it. But I'm still a little bit concerned about the rendertimes/noisyness that can be a drag with these "unbiased"-renderers.

Anyhow, I have a strange problem now when I use a HDRI to light a car scene. When I have the "Imp.samp." unchecked the car renders pretty good but my groundfloor is suuuper noisy. So I click that checkbox "Imp.samp." and the floor turnes out great, but then I get a strange reflection on the hood off my car. Please see the pictures and I think it will make sence.

https://dl.dropboxusercontent.com/u/538 ... shot.1.jpg
https://dl.dropboxusercontent.com/u/538 ... shot.2.jpg

Can this be a bug for the cinema version, or can it be something with my car-shader maybe..?

Thanks,
Roger

[bepeg4d]

hi, i suggest you to always load an octane image texture node before loading any image, in this way you can control the gamma of the texture. since octane works in linear space, it's extremly important to load the imagetexture node first, especially for hdri where the gamma must be set to 1, for 8bit texture the correct gamma is 2.2.
you can always play with the gamma for obtaining particular results, for example higher gamma values for hdri gives more hard shadows but with more noise to clean
ciao beppe

[HandsomeRob]

Thanks! That worked like a charm, noiseless in a couple of seconds..woho

Thanks again,
Roger