More Flickering lights

[grasshopper]

Hi Does anyone know whats causing my light fittings to flicker on and off.

They are modeled down lights with a Vray Lightmat as the light emitter (faked). There is a standard spot underneath.

http://www.gregsteel.pwp.blueyonder....am2_pal_dv.mpg

Thanks

[ene.xis]

check ur AA!
wich filter are u using?

[grasshopper]

I am restricted to adaptive subdiv. -1, 2 because of render time.
I have been using the area filter set at 1.5. because i don't know any better.

Do you think video filter might of helped?

I wasn't sure it is a AA problem as the lights are the only things that flicker.

[percydaman]

-1,2 aint gonna cut it for animation. you need to suck it up and use minimum 0,2. I can't think of another thing to try, except video filter, but thats really going to soften the entire frame.

[ene.xis]

i ain´t sure either , but i m betting on AA so far...
those brighter pixels r harder to deal AA-wise, so they r the problem to tackle...
are they contributing to direct lighting?if no just hide them and test if there occurs no flicker...

[grasshopper]

percydaman -1,2 aint gonna cut it for animation. you need to suck it up and use minimum 0,2.

ts taking between 5 & 9hrs a frame so i can't up the AA at all. For the rest of the scenes i have reduced the size and glossy settings so i might be able to increase it for them


ene.xis

I'll replace the Vray light mats with something duller and see if it helps.

Thanks for your input folks

[dapeter]

5-9 hours a frame!? That's crazy for something like that... what kind of computer are you on?

I usually try to make sure the vraylightmtl objects are just over 1.000 in the rendered frame window, anything brighter and the AA gets a bit more difficult. That said, it has to be the undersampling that's causing this, I think you'll have to do 0,2 to fix it.

The quickest way without increasing rendering times would be to isolate the vraylightmtl objects and render them out seperately with higher AA settings. Then comp this over the existing animation.

[thomes]

hi grasshopper

i think we have the same problem...

didn´t yet try the tip, but i hope it helps...

look here

http://www.chaosgroup.com/forum/phpB...ic.php?t=19513


thomes

[grasshopper]

Thanks dapeter.

Tell me about it it that frinkin bookcase or the bookcase ends to be precise , 2 layers of transparent frosted (glossy) plastic with a overlayed graphics. the only way could get it to look like the designers wanted it was to build it as it would be built. I have since refined the sub divs and glossies & got them to render about twice as quick for later scenes.

I'm sure my vrylightmats are set to 1 or 1.1 no more anyway.

Its rendered at 1024x576 and i've got a P4 with 4Gb ram butmost of the render nodes are P4's with 512Mb Ram.

[grasshopper]

Thanks thomes, did the sub pixel mapping & clamp output help at all. or higher secondary ray bias. (whatever that is)

[DaForce]

What are your render settings.. speciaically your IR map settings. is the clr thres below 0.3? if so that would be killing your render times... but man P4's with 512mb ram

Get one quad core and replace all those machines hahaha.

Also your back ground looks bad when the camera moves as the sky map is set to screen mapping

[grasshopper]

Hi DaForce,

My IR settings are
Min -4, Max -2, HSph 35, Interp 25.
Clr 0.4, Nrm 0.3, Dist0.1

I have precalculated LC & IR maps but there is quite a few standard spots so as i understand it they are calculated on a per frame basis.

The sky is a still i added in post using premier. Have you any better solutions?

4 Core 2 duo's arrived the other day to start a dedicated farm with 2G ram in each so when my dongle arrives we'er upgrading everything to RC3 and hopefully bye bye 9hr render times.

Thanks for your input do you still think i could i prove rendertimes through IR settings

[DaForce]

Those settings seem ok. Nothing to crazy there.
For your glossy materials make sure your subdivs are not too high... i.e. under 20.

For the background, best to do it in 3dsmax, if you have a 360 map just apply that the env with a spherical mapping type in the material editor.

If the camera is moving using a single image is bound to look crappy.
I have some 360 sky panos that you could use if you like.
http://www.apex.net.au/~daforce/www....lpanos/images/
The are not all that high res but might do the trick.

Of course a nice HDR might look good as well.
I think this one is really high quality, nice sky and free
http://www.chaosgroup.com/forum/phpB...&highlight=hdr

Do the lights flicker if you dont have the vraylightmtl there?
Might be worth while doing that as a seperate layer and combining in post or just do the glow/white parts in post.

[grasshopper]

Thanks man, Nice Links

I'm not sure i can handle rerendering with the background in max but i'll put a map in the environment next time. i just presummed you got more flexability adding it in post.

I have little experiece on post production but I'll try rendering just the vraylightmats and add them in. The thing is the lights show fine in the rest of the scene

http://www.gregsteel.pwp.blueyonder....m2%20_xvid.avi

I think must probably be the AA at that distance (small objects) with the bright mats. Could adjusting th dist thresh help?
Thanks Again

[DaForce]

Yeah the sky looks really bad when done in post that way, not to mention physically impossible
Adding it in 3dsmax will look alot better.
You can add the sky in post when rendering stills that fine, but as soon as you have camera animations it really needs to be done in max.

Adjusting the dist threshold might help. but that will affect the IR map, as others said the problem you probabaly having is with AA.
For a test try rendering those few frames were it flickers with QMC/LC just to rule out it being a IR map problem.