Sampling tutorial for V-Ray 3.20

[ali_cgi]

Hi Vlado,

Is it possible to control GI settings separately using this method, with brute force/l-cache, I am noticing in a studio type scene everything is clean other than the GI pass,

Cheers, Ali

[Monogon]

small question..
you set the global DMC multiplier to 0 but rendertime decreases when setting the "subdivs multiplier" of the fur to "0". how are/arent't those related?

[joconnell]

Subdivs multiplier tells vray to swap between using primary anti aliasing or secondary shading samplers to clean up an object. Hair and fur are really aa heavy so you'll need lots of AA. The difference between the global dmc and the subdivs multiplier though is the subdivs multiplier also controls the minimum shading rate, the global dmc only controls material and light settings.

[vlado]

Subdivs multiplier tells vray to swap between using primary anti aliasing or secondary shading samplers to clean up an object. Hair and fur are really aa heavy so you'll need lots of AA. The difference between the global dmc and the subdivs multiplier though is the subdivs multiplier also controls the minimum shading rate, the global dmc only controls material and light settings.

For SP3, V-Ray will know that hair and fur in general require lots of AA, so it will reduce the shading samples automatically in order to speed things up.

Best regards,
Vlado

[joconnell]

Yep, I don't want to be stealing anyone from chaos's chances to tell everyone about such good things though

[fraggle]

Just make a test using Vlado approach using 3.20.01.
It is an interior scene with vray sun on one side and Dome light (hdri texture) + light portal on the other side.
The region render is 380x554 pixel.
No displacement
Render time: 50 minute!
Workstation: 24 Core Xeon 5650 @2.67 Ghz.
The rendering take forever and the result is not clean at all. Noise + splotches and a lot of AA even on flat surface.
I'm using IR/LC with IR set to high.

I was expecting to get a 5 minute render for such a small render size!

[vlado]

Try V-Ray 3.30 and BF+LC. If it is still slow, can you get me a scene?

Best regards,
Vlado

[fraggle]

I tried, but got an error everytime with this scene on max2016/vray 3.3.

[Oleg_Budeanu]

[ATTACH=CONFIG]27264[/ATTACH][ATTACH=CONFIG]27265[/ATTACH]
Just make a test using Vlado approach using 3.20.01.
It is an interior scene with vray sun on one side and Dome light (hdri texture) + light portal on the other side.
The region render is 380x554 pixel.
No displacement
Render time: 50 minute!
Workstation: 24 Core Xeon 5650 @2.67 Ghz.
The rendering take forever and the result is not clean at all. Noise + splotches and a lot of AA even on flat surface.
I'm using IR/LC with IR set to high.

I was expecting to get a 5 minute render for such a small render size!

Well by distribution of samples i can say that you should tweak multiplier by object to get adequate result.

[vlado]

I tried, but got an error everytime with this scene on max2016/vray 3.3.

All the more reason to send it to me at vlado@chaosgroup.com

Best regards,
Vlado

[pg1]

How would your new method work with vray fog? Normally to get the fog to clean up I would increase subdivisions which I guess will do nothing with a global subdiv of 0 and there is no way to select the fog as an object and set its object property?

[fraggle]

All the more reason to send it to me at vlado@chaosgroup.com

Best regards,
Vlado

after converting into proxy some object, that works.
Is this method still valid for 3.3 or not anymore?
I'm still trying to get rid of the noise.

With everything push to 100% on the quick setting, I's still getting a lot of noise.
I've tried with IR/LC as well as DR/LC.
Same result.

[fraggle]

new test with the local subdiv set to 20 in the vray property.
but still noisy...

[fraggle]

Try V-Ray 3.30 and BF+LC. If it is still slow, can you get me a scene?

Best regards,
Vlado

Please find attached a simplified scene. I've tried very hard on 3.2 but was unable to get rid of the noise even with very high setup and unlimited render time...
I didn't tried on the 3.3 as the farm didn't support the 3.3.

Noise is on the reflection map, but even with a subdivision set to 100 (vray property), the noise is better but still visible.
I also tried with no bump map at all (in case), result is the same.
I tried without fallof map, still noisy....
the best result, but not yet perfect, is obtain by putting the Reflection glossiness to 1 instead of 0.4.

I also notice that the following scenario increase the noise (on the wall as well). Such extra light was there to light the exterior.
- Turning on the sky environment
- Adding a Dome light with an HDRI map.

A little bit of noise with a 360° and headset on you head ruined the experience.

I will be happy If you came up with a solution noise free.


DEbug_noise_Vlado.zip

[mienda]

HI,

I find your camera exposure very strange so I change it (shutter speed from 5 to 100) and i have no problem, render is clean and fast (with very low irradiance and 1200 LC subdivs , probalistic lights were on so i switch them off because it could bring some noise).
Hope it could help you

best

mienda