QMC Sampler, etc.

[craiggorton]

I can't find an explanation of the settings under the "QMC Sampler" roll-out. I've noticed the defaults have changed from the beta ones, but I don't really know what these control.

Also, what does the refraction setting under fresnel reflections do? Should I set that number to the same as the reflection? Does it matter? What about it's color?

Thanks,
Craig

[dalomar_cg]

Re: QMC Sampler, etc.

As far as your first question here is the explanation from Spot3D. http://www.spot3d.com/vray/help/150R...params_qmc.htm
Basically the only two I mess with are the adaptive amount and noise threshold. For aa I usually have it on 1 or .95 thats the most adaptive and will generally be quicker. As a side note IM doesn't like an AA of 1, but .95 it seams fine with. With the noise threshold thats basically telling vray what is the acceptable cut off value. I try to stick with things around .01 for general purposes. If I want faster previews I will go as high as .05 (which is only sutable for previews). For finals I usually try to leave it at .01 or shift it down to .005. I also may go as low as .001, any lower than that is just unnecessary and NEVER use 0 (that basically is a perfect solution and that takes FOREVER). Remember that the QMC sampler settings are basically the quality control for almost every aspect of the render. That means that doing things there are going to affect everything (positively or negitively), so just run a few tests before you start throwing values in there.

As for your second question, Its really just part of the falloff texture. Most of the things with peculure names are just things that are named that way in the SDK so thats what Joe named them. You should have the IOR values for both slots in the fresnel settings matching, although changing it will affect things such as glass. I wrote a tutorial a year ago that explained abit of all that and had some rendered examples of the differences. I will see if I can track it down.

[dalomar_cg]

Re: QMC Sampler, etc.

So I found the tutorial. As I said, I made it a year ago, so needless to say there are some V-ray things that have changed. I was also quite a newbie when I made this, so not everything is explained very well. Page 3 has some of the tweeks with the refraction settings within the fresnel maps that I was talking about. Enjoy.

http://www.box.net/shared/gse9z73r6b