Colour threshold

[sherridge101]

Hi All

In this vid, at around 25 min 50, Simeon Balabanov mentions using only the Colour Threshold (of the new variance based sampling) to dictate the quality of V-Ray and that there's no need for tweaking of light or shader samples.

https://www.youtube.com/watch?v=O2HN3Fj54j0
Simeon Balabanov (Chaos Group): The latest improvements in V-Ray for VFX and Automotive

Is Simeon referring to the Noise Threshold, or is there another Colour Threshold to use to control overall quality?

Cheers

[s.balabanov]

Hello

Yes, that is correct. I refer to the "Threshold" parameter in the Image sampler roll-out. It is named "Noise threshold" when the progressive sampler is enabled, but essentially it is the same thing.

When using the default settings from 3.3 onward, i.e. not using local subdivisions, GI set to Brute Force/Light Cache, and Image sampler Max subdivs are sufficient (24 by default), the one setting that changes the sampling quality is the "Threshold"/"Noise threshold".

Let me know if that clarifies it.

[sherridge101]

Hi Simeon

Thanks for the explanation.

Does the Threshold setting control the GI quality also?

[s.balabanov]

If Brute Forces is set to primary bounces engine, yes.

In the default settings, Light Cache is used as well (as secondary). That's why I suggest using the Quick settings, GI quality slider to easily adjust the Light Cache's settings. The Brute Force will be taken care from the "Threshold" setting.

Essentially, the quality of every scene can be set by using the Quick Settings GI quality slider for the Light Cache and the "Threshold" for everything else.

[sherridge101]

Great stuff, thanks.

Last query, is there a way of viewing the Light cache separately, or as a Render Element.

I’m thinking that I can see the quality level of the lighting and shaders quite easily in the the RT window (tweaking the Colour Threshold), but it’s possibly a little trickier to view the Light Cache on it’s own - to check it's quality level.

Cheers

[Svetlozar Draganov]

There isn't a separate render element for LC, its contribution could be seen in the GI and rawGI elements but it will be mixed with the contribution of other GI engines like IM or BF.