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Re: Interior shot quality

Posted: Thu Jan 24, 2013 12:48 pm
by gueoct
abstrax wrote:I don't know the plugin, but I assume that "samples" corresponds to "sampling_rate" in standalone Octane. This parameter allows you to weigh how much a particular emitting material is sampled. Usually Octane weighs emitting materials depending on brightness and area, but sometimes that isn't enough and the user can take control with this parameter.

I guess the problem with your scene is that it's very hard to find a path to the light sources, which are "hidden" deep inside the lamp shades. Another problem is that half of the emitting polygons don't contribute any lighting since they are pointing up where the lamp shade and the IES profile block any light. The second problem is easy to fix. Just remove those emitting polygons at the top:
lightfix.png
The first problem is harder to solve. The only simple "fix" I can think of might be switching to PMC.
I moved the light sources down a bit, increased the samples, but it did not help.
BUT switching to PMC did the trick!!!!!!! Now it´s converging much faster and with less grain.
Can you tell me why?

Re: Interior shot quality

Posted: Mon Jan 28, 2013 11:21 pm
by FooZe
PMC is path tracing with a custom sampling method, meaning that it is more efficient for low ambient/direct light interior scenes as it spends less time on samples that don't contribute much to the image quality.

Thanks
Chris.