white dots in my vray rendering... help!

[fabitolindo]

Hi,

 

I had the same problem after altering the Indirect Ilumination Mode (from single frame to Animation (prepass) and (rendering))

 

I tried everything from this thread and nothing worked...

 

What I did was uncheck "Show Samples" in the Indirect Ilumination tab under Options.

 

I don't know why but this worked!

 

Good Luck!

[siddhu.bk]

Hello All,

 

I have faced same problem several times. It has nothing to do with your v-ray render settings, all you have to do is change your v -ray material settings.

 

Here is the solution

 

1. Open material editor(press M)

2. Select the material in which you are using reflection glossiness settings (Reflection section - where the refl.Glosiness value is other than default value = 1)

3. Go to options tab change the value of Treat glossy rays as GI = Only for GI rays to Always.

Follow the same procedure for all the material in the scene which is using reflection glosiness settings.

This should fix the problem.

 

Good Luck !!!!!!!:)

[3Dimensia]

Under Vray system uncheck Max compatible ShadeContext

 

I was having a similar issue (but larger white spots). I went through this thread, trying everyone's solution. None helped until I did THIS!! Thank you!!

[schwimmer]

uncheking "show samples" worked for me...

 

Hi,

 

I had the same problem after altering the Indirect Ilumination Mode (from single frame to Animation (prepass) and (rendering))

 

I tried everything from this thread and nothing worked...

 

What I did was uncheck "Show Samples" in the Indirect Ilumination tab under Options.

 

I don't know why but this worked!

 

Good Luck!

[almashjary]

checking "sub pixel mapping" on the color mapping tab... helped..!! Thanx..

[Terri Brown]

Oh my I can't believe this forum is finished. I have tried all the options outlined above and no change - still getting those ugly white spots.

 

where do i find the rQMC settings??

 

here's my test render:

 

and my render settings:

 

help would be much appreciated as I have a super tight deadline!

 

Thanks guys...as always the Viz community is our lifeline

[Terri Brown]

I believe it's an irradiance map issue - doing sample renders and pumping up my subdivisions and samples seems to smooth it out. doing a test render as we speak. Just worried that'll interfere with other things...

[Chris MacDonald]

QMC stands for quasi-monte-carlo and was the name for the implimentation of the old method VRay used for sampling, it has since changed to DMC sampling (deterministic monte carlo), hence you not being able to find it.

[Terri Brown]

cool thanks. still got no solution to the white spots other than photoshopping them out.

[Ismael]

How are you lighting the scene and do you have Caustics turned On in the roll out? I only increase subdivisions as the samples will end up blurring details.

[Terri Brown]

I had only refractive caustics on. Do u think that's the cause? I'll switch it off and re-render...will let you know.

 

thanks!

[Terri Brown]

In terms of lighting:

 

Main light source is an HDRi light. I also have a VRay sun is pump up the shadows, but somehow think that was a bit redundant.

There's a VRay Light Mat on my two interior lights with GI switched on, and also 6 Target Sphere Photometric Lights to light up the interior.

 

Here's my latest render. The spots are better, but not gone (i'll try switch off caustics), but what I can't fix is the graininess on my wooden floor (There's a map on the Glossiness - I have pumped up the RGlossiness all the way up to 90) and my ADMC Max Subdivisions are 95! I tried pumping up each light's subdivisions and even the camera's, all individually, but the graininess wasn't caused by any of those. It's undoubtedly my glossiness map, because when i switch it off graininess disappears, but surely 90 is a high enough value for the RGlossiness subs?? And to pump up the ADMC Subs even more is killing my render times.

 

So two probs now - spots and grainy floors!

 

Any help would be much appreciated

 

Here's the render:

[Terri Brown]

switched off caustics (refractive) and it did the trick!! Thanks so much Ismael!

 

now I just need to figure out how to render with my reflect glossiness map for the floor (which I don't want to omit as it adds some realism) minus the noise grain I even pumped up my ADMC max Subs to 110 (which seems ridiculous) - no luck.

 

any ideas? anyone?

[Chris MacDonald]

Well first find out where the noise is coming from; is it from the lighting, reflections, or GI.

 

First off I'd rule out GI noise, as that is usually of a more soft/splotchy kind and not grainy.

 

To find out where the noise is present, try adding some VRay render elements, specifically the Rawreflection and Rawlighting filters - these should show you where the noise is coming from.

 

At a guess, judging how smooth the rest of the render is in reflections and such, and that the most noise on the floor is where the light falls off into shadow, i'm guessing it will be your lighting pass that shows the noise. If this is the case then just try increasing your main light subdivs. With HDRI's I usually have them set to a minimum of 16, but usually aim for around 32 to avoid noise.

[Terri Brown]

I had already tried setting my HDRI to 32, and then 64 when that didn't work. No change whatsoever. I previously tried saving out my Raw render passes to do exactly what you suggested, but for some bizarre reason was getting the error msg: VRay Output encountered error while saving to file...or something along those lines. Will try again to see exact error msg.

 

I did however manage to save out a Raw Reflection pass - which shows loads of grain:

 

But then do i need to pump up my RGlossiness Subs on my material even more than 90? When i did a test of as much as 130 it showed not much difference.

[Chris MacDonald]

Theoretically you could push the subdivisions for your reflections through the roof and still end up with lots of grain because the anti-aliasing/DMC sampler has already reached the noise threshold and will no longer continue to subdivide given that it has met the "minimum samples" criteria. A bit of a mindf*ck to get your head around.

 

Rather than go nuts with your subdivisions, try adjusing the sampler threshold to a smaller number. The default is 0.01, so try halving it to 0.005 and see if the noise clears up.

[Terri Brown]

i'd already put the threshold at 0.005 (believe me i did a LOT of reading up before posting here!). But I stumbled apon this article by PG that I've glossed over before: http://www.peterguthrie.net/blog/2012/02/hdri-lighting-glossy-reflections/comment-page-1/#comment-4691, and I believe that's the answer. haven't had a chance to try it properly, but will def let you know if it works!

[CliveG]

What about the Vraylightmat?

 

Just a thought....

[Terri Brown]

yeah i checked that already.

[waelalzaher]

Hi I'm sorry to be late, you seems to be bushed of this but trust me It's all about lighting, check your light Parameters

[carolinachica]

Hello! Go to the Render Setup, and try to activate "Sub-pixel mapping" and "Clamp output" in Color mapping parametres. Good luck!

[Guest malekmax]

that's it man thank you very much

[aminur rahman]

Under Vray system uncheck Max compatible ShadeContext

 

Thanks...It worked in my case.

[aminur rahman]

Hello! Go to the Render Setup, and try to activate "Sub-pixel mapping" and "Clamp output" in Color mapping parametres. Good luck!

 

This worked too...Thanks.

[Terri Brown]

sub-pixel mapping never did the trick for me. what seemed to work was deactivating caustics.

 

good luck everyone...seems to be luck of the draw!