shadow/reflection flicker in product shot animation

V-Ray V-Ray for 3ds Max Issues
1

I do a lot of these product shots on white psyches with camera animation
and always get lots of shadow flicker. I dont know how to get rid of these flickers on the ground plane or in the
small shadows where the product meets the floor. I thought my IR and QMC setting were pretty high
already. You can see it in the reflections of the glass that is on the ground. i just have 2 vray lights being reflected
and black environment-simple setup.

Here are my setting..

2 vray lights, store IR on
glass is vray material, no interp on reflect or refract, fresnel on
AA= adapative QMC 2/4, area filter =on
Prim bounce=IR map, Second=QMC
IR map -3/0
HSph= 30
Clr=0.35
Nrm=0.4
Dist=0.2
Blur GI=off
QMC Sampler noise = 0.002, samples=8, Global=1

here is the clip…

should i be using Adaptive Subdiv instead of QMC for AA?
should i be using raytrace area shadows instead? (store IR off?)

anyone else do lots of these have any advice? help please!
thanks!

2

Well the AA wont make a different as large parts of your image are flickering.

I would suggest not storing the lights in the IR map.

Are you using a saved IR map or rendering it only every Nth frame?
Looks like an IR map problem to me.
Do any of your lights move? (i assume not)

Ir map can be bad for animations but not to the extent that you seeing here I wouldnt have thought.

3

I am not using a saved IR map since there is animation involved and its being cacld every frame. Lights not moving, nope..Seems like a simple scene not sure why its so bad GI flicker..especially with 0.002 noise thresh. I could make the IR map -3/1 but render times go through the roof. (sigh)

4

could the scale of the scene (like if the glasses were very small) in max space be affecting anything? i noticed when i merged the glasses they were pretty small compared to the lighting setup, which i made smaller to be more proportionate to the objects..

just a thought..I am grasping at this point

5

very unlikely I would say.
But you never know.

Try something for me… try rendering some frames with LC/LC and see if thats any better, calc it in flythrough mode.

Are there any errors in the vray log?
Also make sure the stationary glass isnt intersecting the florr.

6

thanks DaForce…well easy things first…
glass in not intersecting floor, no errors or warning in log.
By LC/LC I am assuming you mean Lightcache in both primary and secondary bounces? i have never used that but i wil give it a go. what is flythrough mode? Still learnin’…

Thanks!

7

Yeah thats what i mean by LC/LC 1stbounce/2ndbounce

In the LC rollout there is a pulldown menu at the bottom change it from single frame to flythrough, that will calculate the LC for the entire animation in one go which can help prevent flickering. Set the subdivs to around 2000. as that will need to be spread out over the animation length.

This certainly isnt a final rendering option but im just getting you to try it to see if it renders cleanly.

Also what build of Vray are you using?

And if all else fails, if you want you can send me your scene and I can give it the once over and see if i can find the problem for you.

8

hey thanks..i will try that now. i have removed the water to see if that was a factor but same problem, so its not that. if it works then, i guess i want to use LC all the time since i do a lot of camera moves on white-background objects. I will post the results…I am using 1.50.06

if no good, that would be great if you could look at the file…thanks again!

9

forgot to ask..
with LC do i want STORE DIR LIGHT on? sample size?

thanks

10

1.50.06 :shock: ahh thats a “dodgy” build man its a renamed 1.48.03 build AFAIK… you shouldnt be using that!!

Download the RC3 release from the support section of the chaosgroup website.

Then try render again… you never know :smile:

But yeah I would be happy to have a look at the file for you.

11

Store direct light = NO

leave the sample sizes etc.. alone at the moment except change the filter to fixed

12

ok..hard to tell cause the scene is kinda dark now.

this is with LC and those setting you mentioned..

here is the file if you like to see it

thanks!
M

13

Well it seems to not be flickering at all now with LC/LC hmm ok..

looking at the file now.. will report back shortly.

14

highpoly, make sure you are using an official build of vray. 1.50.06 is not an official build.

15

yes, since i havent ordered a dongle yet. i guess i will go back to the 1.4803 version for now..thanks

16

1.48.03 is the EXACT same as what you were using.

Download RC3 and choose to install with the software dongle. you dont actually need the hardware dongle at the moment.

17

ok..will do! thanks

18

Ok, i just rendered the anim out with RC3 and its still flickering as it was in yours. I will have a look better when i get home shortly (in the next hour or so) and try and solve it then.

Its a little tricky to do at the moment thru VNC.. haha

19

yes. VNC would be a little tough eh? lol

This seems like a pretty simple scene..dont know why its so hard to solve the GI flicker…

If you get a chance later to play with the scene thats great..thanks so much for your help..I will keep at it too!

Thanks!

20

I think i stumbled across it just then.

Just rendering now to confirm.. but untick store with irradiance map in the lights and drop the subdivs to like 8
Rendering now will report back soon.

hmm that didnt really help.. wait till i get home.