Volumetrics through a fine aperture

[AdamT]

What kind of shadows are you using hard or soft shadows? If the latter maybe a bias or resolution issue?

[Mikka]

Hard Shadows.

I'm slowly animating a polygonal surface, with which the alpha mapped texture is applied to. A light shines through the surface using hard shadows. But when the surface moves slowly, the light flickers weirdly fast and unrealistically, out of time with the actual surface.

I thought it had something to do with bias or resolution aswell, but this is hard' :P

-Mk

[crash_tx]

Would using a phisical cone mapped with a fog and luminance texture help control the flickering?

http://home.austin.rr.com/tbirmingham/screenshot02.jpg

[Mikka]

Unfortunately not, as I'm using an animating noise to produce the holes for the light to shine through, and I dont know where each of the shafts will be as there are ~50 of them.

I'll try and post an example later on, hope I'm being somewhat clear with my explanations :)

-Mk

[crash_tx]

oh... I understand now... the shape and positions of your openings are animated as well.

I'll keep posted to see how you take care of this one because I've thought about animating sun patches through storm clouds onto a seascape. Sounds very similar.

Good luck!

[Mikka]

Thanks for your help and interest crash_tx :)

As its friday and im outa time I've had to just add some foreground details and blur out the background to make the flickers less evident, they're still there but now the attention is on something else.

I suppose i bowed out of this problem with an OKAY result, but its the weekend tomorrow and renders going monday :surprised ouchies.

wiggy'


:beer:

-Mk

[flingster]

what happens when you slow down the noise...surely this will help reduce the whole quick flicking...sounds like the noise is animating very fast so you are seeing quick light penetration..then effectively cut off....dunno just a thought. not it this case but i've had problems with using animated noise to control other things eg cloner or something...as i was getting quick flicked objects...it can be very hard to have some control over the randomness...dunno just a thought. Everything you mention points to the volumetric light setting...but i would also do a quick test by really slowing down the noise and see if you get the same problem...:shrug:

[WQP]

Is this something that can be fixed by adjusting your depth settings under rendering preferences. I was playing around with alpha mapped hair and realized to avoid a bunch of glitches I had to vastly increase my ray depth.

[Medicine Horse]

Sample radius is key here for the light.. high values look like ass but low values look mint. Your render times sky rocket though.

-M

[nendo_3d]

try turning ur visible light to volumetric and turning ur noise down. i am hoping ur mean something like this but without the stars

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