Grant Warwick- Mastering Vray: Material Ideas Needed.

[Dariusz Makowski (Dadal)]

Indeed, it is! I'm wondering if cranking up the intensity multiplier of HDRI will not get it render faster? Sadly, it can't be apply in this scene.
But it seems that lighter is the scene and faster is the render.

Well like I said its very difficult one. If you are going to use Adaptive DMC - Blurr HDR a little bit. Depending on the light sources in image it will depends. You will loose a little shadow accuracy but that should be fine with night shot. Remember the smaller the light source the harder it will be to render for vray. So blur should give it a little speed up.

Using Adaptive DMC =
2/32 min max.
IBL 256-512 samples.
That should get u started on LIGHT ONLY Pass. I don't discuss reflection that's way more complicated.

However I would suggest using Adaptive Subdivision. In which case you are looking at:

1/2 min max samples AA
64-128 samples on IBL. That should render as long as adaptive DMC but it will be cleaner. Shader samples depending on gloss if its around 0.7 I suggest 24... Its hard to just shot out the numbers...

Hope this helps...

[fraggle]

Do you mean the min / max value is 1-2?

That is crazy. Remember, the Max value divides the global samples. So having 300 subdivisions isn't the "actual" number. It's relevant to the max AA samples.

AA set to 1/4.
Still looking for a way to get rid of the noise in the shadow transition zone and specular zone.

[DaveKW]

I think that may be because you've got 22,500 light samples (300x300 = 90,000 samples / 4 AA samples). Is that correct?

[fraggle]

I think that may be because you've got 22,500 light samples (300x300 = 90,000 samples / 4 AA samples). Is that correct?

Yes, Light subdivision is 300 and AA is 1/4.
Will try to push the light again, but the render time is really going up too.
-> no , doesn't make any improvement even with light subd set to 600.

[grantwarwick]

Email the scene to me at
admin@sathe.com.au

This may be one of those rare cases where you need to adjust the noise threshold (Not the same as CLR threshold)

I'm also up for testing Adaptive Subdivision again and potentially starting a shit storm haha

[Dariusz Makowski (Dadal)]

Email the scene to me at
admin@sathe.com.au

This may be one of those rare cases where you need to adjust the noise threshold (Not the same as CLR threshold)

I'm also up for testing Adaptive Subdivision again and potentially starting a shit storm haha

Sorry Grant

[grantwarwick]

AHahah I'm almost certain it's not going to be of any benefit whatsoever and there is simply something in the scene I'm missing.
(I've had to balance HDR's countless times now so I'm well aware of the noise dome lights bring to the table :P)

But if I am wrong, I'll happily fall on my sword :P

[Raven]

Hey fraggle can you post the HDRi?

I have done a few tests with some of mine, and no real issues. Just one or 2 but not noise problems, more object edge and shadow edge.
I think reducing the Clr thresh should fix it or playing with the HDRi resolution. Sometimes I wish DMC had Object outline like subdive.
I will post images shortly.

[Dariusz Makowski (Dadal)]

Guys Using AA to clean up light noise samples is the worst possible thing you can do.

[grantwarwick]

Guys Using AA to clean up light noise samples is the worst possible thing you can do.

This thread is an absolute mess.

Considering breaking it into Support and discussion but then we lose the potential of overtaking the biggest thread on the chaos group forum haha.

[grantwarwick]

Updates on a couple of the multi layered metals

[DaveKW]

Very, very nice. Are these with the GGX based BRDF's you've been experimenting with?

[Raven]

Not good enough, try harder...

... ha ha, these look awesome Grant.

[grantwarwick]

Those GGX experiments are more an understanding excercise than anything. I personally think my materials produce more realistic results but they take a lot more work...
Most of my materials are based purely by eye but based on the idea of nesting reflection layers.

In the 10 years of doing CG, I've only ever seen or heard a couple of artists use this approach, most notibly the artists at ILM working on Iron Man.

A little back story to anyone interested.

ILM took real world scanned data of the suit materials but never actually used the BRDF data because this process captures the material in its "perfect" form.
In reality, you have all sorts of things causing impurities in the material and that is what gives it it's realistic appearance so they ditched it and went with an
approach they called "Fresnel Nesting", in other words, blending two materials with different fresnel values to create an entirely new specular distribution.
Pretty genius if you ask me, I can't take credit for that, only pushing it further.

I've taken that approach and advanced it using Joconnells approach of manually tweaking reflectance curves with falloff maps based on data from http://refractiveindex.info/ (I don't use fresnel anymore, take that Christopher Nichols you &$#*$ bastard!)
Might seem like a mouthful but it's the lesson I'm most looking forward to.

[tricky]

Just watched through your video whilst I was waiting for a render to complete. Great job so far fella! What I really was thankful for is that it follows what I have been trying myself from a few recent threads on this forum (thanks for everybody's help). It was just far easier to see cause and effect in a vid.

One little question though. In the first half of the vid, you were using 1-4 for the image sampler. I blinked and you had changed it to 1-8 (which obviously increased noise on the shadows and reflections, but also sped up the rendering). Why did you do this when 1-4 seemed to be working OK? By upping it, it meant you needed to increase subdivs on lights and materials to get back to where you were with 1-4.