Noise problem in RC2

[teabag]

Hello everybody,

Ive got a question regarding the noise which is present in my WIP scene and is apparent on not only on all the glossy objects but even on glass reflection which has no glossy finish at all....

I am posting this topic withoup a picture as i am out of the office at the moment , but i was wöndering if you could somehow help me on this, possibly give me a few hint or tips.

Here are the scene settings as i remember:
GI method IRR/LC
Image sampler: fixed at 5
Aliasing filter: off
IRR Hight preset, 60/30
LC 3000 at 5 passes, single frame
rQMC noise at 0,001
Global QMC subdivs at 100

Environment:
Vray sun + sky in vray environment slots
GI environment at 1.0
Refl environment at 1.0

Reinhard mapping, physical camera, no subpixel mapping, no clamp output

...i thought that with these setting and just one (vraysun) light in the scene i should get pretty much noiseless solution...but i was wrong

Do you think the noise can be cause by insufficient lighting? perhaps i could raise the GI multiplier to somewhere above 2.0 ro increase overall ambience of the scene and just play with the physical cam settings again?

Thanks a lot

Martin

[Clifton Santiago]

Could you post an image with the noise you are referring to? Normally noise should not be a problem with IR/LC solutions, especially with your rQMC noise at .001. In 1.5, I usually set mine at .01 and have no visible noise.

The only time I have had problems are when AA creates sampling noise in a low-light scene (and I use LWF). My solution was to increase rQMC samples and global subdivs to 16 each. If you do this remember to turn down your IR map Hsph subdivs to like 4 (4x16=64 Hsph subdivs) to keep render times down.

[jacksc02]

something doesnt seem right martin, your settings are pretty high.
I think you need to post up an image, then it should be an easy thing to fix. Also, if you want to send me part of your scene I dont mind having a look at the problem.

[teabag]

sorry about the delay....here are the two renedrs so far:
first one with only vray sun in the scene and 1.0 GI multiplier, settings as described above


and the second one with another plane vray light in the scene plus the global GI was increased to 2.2


the first is reinhard, the second is gamma mapping

does vraycam sampling value influence the noise, cos in the first one the subs were at the default 6, the second were at 25.

thanks for the help guys

Martin

[Clifton Santiago]

Maybe its just me, or maybe the resolution of the posted images but I don't really see GI noise in your renderings.

The only "noisy" parts of the image appear to be on the surfaces of your glossy reflection materials. This might be caused from having your glossy reflection subdivs set too low. Try setting them at 24, and then check Use interpolation to speed things up. If you are animating the scene do not use interpolation, but try the Use light cache for glossy rays option.

Also, your edges seem a bit soft... if you are using Area AA, maybe try switching to Mitchell Netravelli.

[teabag]

hello,
using none AA filter .....anyway i was more on about the noise on glossy parts....i ve got them all at 25, no interpolatioon...i was thinking that when i raise the minimal subdivs in rQMC settings, this would override the values in the material editor....am i right here?

[teabag]

something doesnt seem right martin, your settings are pretty high.
I think you need to post up an image, then it should be an easy thing to fix. Also, if you want to send me part of your scene I dont mind having a look at the problem.

..sorry jacksc02 i cannot post the scene link here i dont have an ftp address, but i can mail it to u if u r still interested

cheers Martin

[vlado]

It could be the bump mapping too...

Best regards,
Vlado

[Clifton Santiago]

I always turn up my global subdivs to 8 or 16, but it seems the material glossy subdivs are independent of that value.

[teabag]

vlado:
i always set my bump map filtering to somewhere from 0,1 to 0,3...is that a right value or should i go either closer to 1 or 0?

clifton:
strange...i thought that since the global subdivs are called "global", they should influence all subdivisions in the scene...mostly the subdivs in the mat editor

[Clifton Santiago]

I thought so too, but I did a test with global subdivs at 1, material glossy subdivs at 24, and rendered. Then I did globals at 8, and material at 3, which should be 24, and rendered. It looked like 3, not 24. I'll test it again real quick...