Unbiased Rendering and the Endless Battle with Noise

[csmallfield]

Hey all,

I recently downloaded the demo and I am really impressed. I've been following Octane for a while, really curious about where it will go. The plug-in for 3DS Max seems like a really nice step in the right direction.

I've got a couple of questions that I can't seem to find out in my searchs through the website and the forum.

1) Noise. I have been in the process of testing many renderers over the last 6 months, specifically photorealistic ones, Arnold, Vray, and Maxwell. All have pros and cons of course, but the major con with all of them is noise. I can get a really sweet nicely lit HD720 image out of the 3 renderers I mentioned in a matter of minutes, but the noise is unnacceptably high. You render it longer, it gets minimized. But now you are in the 2 hour range per frame. To really get the noise out it seems you can't expect to render something moderately complicated under 6-10 hours a frame. This, for a small studio is just not possible. Hence the reason I am looking into Octane.

In the forums, nearly all images fall into the range of unnacceptable noise or almost tolerable amounts of noise but with pretty long render times. On the website there are some really nice car renders that look nearly noise free, and I am curious what these times are like? Specifically the green and yellow car by Radiance, 2nd picture in in the gallery. I know it depends on scene complexity and machine, but for the sake of argument, let's use the car I mentioned and say it is on a 2 gpu beast machine. Can you get noise free images like this in a reasonable time?

2)Heat. Graphics cards don't exactly have the best track record for intense ongoing processing without overheating or just sort of falling apart. Has this been an issue for studios rendering with Octane on a render farm, being that long sustained work is not the intended work of a graphics card? It's a bit scary to invest in a GPU powered render farm to have a computer fail every two weeks or so after an intense render job.


I would love any input you guys have. Thanks for your time.

Chris Smallfield
Head of 3D
Shape Minds and Moving Images GmbH Berlin

[mib2berlin]

Hi, i think with a reasonable gpu server you get rendertimes in minutes range, here is a
solution from renderstream up to 8 GTX 580 or tesla cards.

http://blog.renderstream.com/2011/07/re ... #more-1319

Here is a video showing octane at 8 GTX 580, from 3.42 about animation.
Itis a little boring presentation but an overview.

http://www.youtube.com/watch?v=CZ1IRQTqMMY

The actual octane customer version includes a new render kernel (pmc) to reduce noise like MLT (http://en.wikipedia.org/wiki/Metropolis_light_transport)
and Sub surface scattering, the next release includes instances to save memory for big scenes like trees or grass.

Cheers, mib.

[colin]

plus, it's worth mentioning the usual car render seems to be quite forgiving in terms of noise. by usual i mean a car on a plane, lit by an hdri. (i guess that's why most of the tech-demos of render engines sport a car render at one point or another...).
the real "pain-in-the-ass-render-scenarios" in terms of noise are complex interiors.

hope that helped.