What's this flickering look like?

[Trapezium]

http://www.dtoxx.com/J_Bug/OldManWalkTest.avi
Please Right Click and Save As...

Just can't get rid of this flickering around the neck. I've had luck in the past by upping the Distance threshold in cases like this but it doesn't want to work for me this time. Anyone know what's causing it?

The head is a separate object and terminates with a slight outward flare inside the collar. All materials are set to double sided.

Standard lights w/ VRayShadows set to area.

What am I missing?

--Jon

[percydaman]

does it flicker if your not using GI? like a test anim just using max's default lighting and no GI? Also does it flicker if your not using area shadows?

[Trapezium]

And the render settings...







Strange that these image tags aren't working...

Almost positive it's GI but I'll do a test right now.

Fast response

Thanks man,
--Jon

[percydaman]

oh try changing your AA to 0,3. undersampling AA really sucks for animations.

[Trapezium]

Ok, tested without GI but with Area shadows on and have no flickering.

Forgot to mention that the details on the head are created with VRayDisplacement and the neck intersects the collar slightly at some frames so could this be the problem? It doesn't remind me of any intersection artifacts I've seen in the past though.

I'm testing with one bounce expecting the problems to still be there so in that case it will have something to do with the Irradiance map. Maybe I haven't been interpreting the Nrm. thresh propperly but I wouldn't think changing this could have anything to do with multiple objects? Does it affect displaced geometry also?

Thanks,
--Jon

[Trapezium]

It's not the AA crawling I'm talking about though. There's some flashing on the neck.

--Jon

[Trapezium]

I'm starting to think it has something to do with the way I've constructed the character. See how the head and body join. Anyone have suggestions on how to eliminate a problem like this?



Don't really want to check for sample visibility as this will really increase render time.

--Jon

Edit:

Just accidentally forgot to properly designate map paths so the single bounce render was performed without the displacement map also. Rendered without flickering so it must have something to do with either secondary bounces or VRayDisplacement.

[simonreeves]

so was it flickering with no gi? - if it is try using qmc aa

it looks like a gi thing really

try turning up the HSph subdivs + interp.samples both upto like 70,70

I found using that + medium animation and qmc 1,4 fixed pretty much all flickering in me animations

[Trapezium]

Yeah, the flickering was gone with GI turned off.



I originally tried both Med & High presets then modified the Dist Thresh from 0.5 to 0.7 still with no luck.

I've tweaked the model a bit to minimize intersections on the back of the neck and I'm going to set it to render this evening with the Dist Thresh @ 1.0 and hopefully that should fix it.

I've just rendered with Show samples on and there doesn't appear to be a lack of information in those areas so I'm completely stumped. Vlado, if you happen to read this would you mind sending me the latest Irrad map viewer working with version 1.46.13?

Thanks,
--Jon

[simonreeves]

did you try just pumping up up the HSph subdivs + interp.samples both upto like 70,70?

[Trapezium]

Whoops I meant to say that I did something like that also and I'm testing to see how he looks without secondary bounces.

I didn't see why Higher Interp Smpls would help in a case like this so I set Hsph higher to 64 and Interp Smpls to 16 for a little more detail.

A single bounce still render just finished and he looks decent so I'll go with it. There are darker areas down in the collar and I'm guessing that the problem was in the secondary bounces which would lead to the Light Cache. In comparing it the test to the same Secondary Bounce frame it looks like the lightened areas were the flickering areas.

I'll see in the morning. BTW, what do you guys think of how he looks? Here's a still of him with one bounce and a preview animation of his walk cycle. He's just a demo piece so I probably won't comp him into a scene or anything.


http://www.dtoxx.com/J_Bug/_scene.avi

Thanks for the help,
--Jon

[Morbid Angel]

looks good imho, for gi, usuakky any flickering is sample related...if you are not concerned for the render times (im not) i just turn on quasi and set samples to like 30 and go home

[DaForce]

great looking character.

FYI the previous image tags probably didnt work because there is a space after the .jpg

[tom schuelke]

Hmm, i didnt read all reples so far.... no time at the moment. but i think as you use lightcache,

maybe the lightcache sampleszise is to big to show enough detail in theese areas in the neck. so the i-map in each frame only can see this only sample not more. if this in one frame is bright, it gets bright, if it in anotehr frame is dark it also gets dark.

theese sort of errors allways seem to appear when lightcach samplesize gets big compared to details, and from the i-map samplepoints there is only seen this lightcachesample.

Tom

[vlado]

Use a High irradiance map preset with -3/1 for min/max rate. A max rate of 0 is typically low for animations with small details.

Best regards,
Vlado