Animation with GI that doesn't flicker

[natty]

Guys,,

just to open the debate again, is there a way to solve this issue in interior scenes ? i have 6000 frames of interior office space to animate and the client wants doors opening, lights constantly changing colour, furniture moving around and glass changing from clear to frost... we have gone through 2 weeks of testing to come to the conclusion we cant achieve what the client wants due to the amount of movment in the GI solution no matter what way we calc the frames... does anyone have a good solution to this or isnt there one? and please Vlado make GI properly animatible ...... with the constant head ache not knowing what really will work or might work is hard work..

[Morbid Angel]

Guys,,

just to open the debate again, is there a way to solve this issue in interior scenes ? i have 6000 frames of interior office space to animate and the client wants doors opening, lights constantly changing colour, furniture moving around and glass changing from clear to frost... we have gone through 2 weeks of testing to come to the conclusion we cant achieve what the client wants due to the amount of movment in the GI solution no matter what way we calc the frames... does anyone have a good solution to this or isnt there one? and please Vlado make GI properly animatible ...... with the constant head ache not knowing what really will work or might work is hard work..

problem is if you use lightcache, and you have objects moving inside the closed space such as interior, the LC will flicker even at the highest settings. There is few things you can do, though they are pretty labor intensive. If you cant find solution with a gi formula, you can attempt some forms of baking.
Another form would be to try some method like using irradience map with values of -1/-1 where there would not be much interpolation hence flickering will be reduced. Though again with light cache, it could be a problem.
But overall, what you describe is a pretty complicated thing to pull off...so, Imo it should be budgeted accordingly and allow for the time...

[vlado]

You could use the irradiance map only, with perhaps one or two bounces with Brute force GI for the secondary engine, and interpolated irradiance maps. There is not much else you can do for the moment.

Best regards,
Vlado

[etown]

I usually always fall back on QMC/LC for interior scenes. Seems like a consistent performer, and the render times are very comparable to other solutions in the end. It is weird how it always changes depending on your lighting and overall scene elements, but that's why there's no perfect render button either. On another note, showing your rendering passes (GI, Lighting, etc) enables you to pin point bad flickering pretty easily. I don't render without them.

[natty]

Hi etown,

Ive always found this solution too slow or too noisy, could you show me your settings for getting a clean solution and fast render frame times?

[Sascha Selent]

Flicker-free GI-animation in finalRender

Hi everyone.

I come over from the finalRender-front and recently added VRay to my render-engines. First of all I´m very impressed of the VRay-render-engine. It provides extremely good quality in extremely good rendertimes. But regarding to flicker-free GI-animations finalRender is still the only one I know where this feature works as it should. Some time ago they invented the two-pass render-method with blending over multiple GI-solutions (I think the cebas-boys where the first ones, correct me if I´m wrong) and it works extremely good and stable, even with very low settings.

Here you can see two examples within I tested this feature:

http://deepartmend.dyndns.tv/exchang...tion-test.html
This is a whitecard-model-animation...

http://deepartmend.dyndns.tv/exchang...-test_mat.html
...the same animation with materials assigned.

Don´t be confused, I added some grain in the post.

As you can see no flickering at all.

I think the VRay-approach is somewhat similar, but for some reason it does not work. I did not make it to get this animation flicker-free with the two-pass-approach in VRay. The best result I achieved was to render the scene in single-frame-mode with irradiance-map with high-preset and lightcache for the secondary bounces. This provided a good flicker-free result - don´t ask me why - I´m still not very familiar with VRay.

I think I will provide my tests in VRay, maybe next week, if I have enough time. I´m highly interested in this feature getting to work properly.

So take a look at the finalRender-examples and soon I´ll provide my VRay-tests.

Best regards.

Sascha

[Morbid Angel]

well im not sure about your setup. In the first test animation, the bounce of the gi is not very noticeable under the couch for example. It almost looks like a form of occlusion. I could be wrong though.
I do agree however, that vray's animation gi has ways to go...

[vlado]

As you can see no flickering at all.

There is flickering on the wall with the window opening (no, it's not the grain).

Best regards,
Vlado

[vlado]

Forgot to say that there are also some improvements in that department for SP3

Best regards,
Vlado

[Morbid Angel]

hyper gi?
kidding.

[vlado]

Hehe, no. But in SP2, the irradiance map for animation is additionally randomized - the "Time independent" option is forced to OFF, which causes the samples to be completely different for each frame. I don't know why I thought it would be a better idea at the time... Anyways, this also explains why a single frame irradiance map might be more stable. For SP3, this is corrected and it makes the irradiance maps for animation much more useful.

Best regards,
Vlado

[natty]

Thanks for the examples Sascha, you can achieve a perfectly flicker free animation quite easily with vray with that level of detail and one light. im talking about a complicated walkthrough with millions of polys and dozens of lights. Controling the GI becomes a little harder.

[natty]

Hehe, no. But in SP2, the irradiance map for animation is additionally randomized - the "Time independent" option is forced to OFF, which causes the samples to be completely different for each frame. I don't know why I thought it would be a better idea at the time... Anyways, this also explains why a single frame irradiance map might be more stable. For SP3, this is corrected and it makes the irradiance maps for animation much more useful.

Best regards,
Vlado

Sounds great Vlado, when do you estimate the new release to be ready?

[Morbid Angel]

should be available in latest beta...if you are into that kind of thing.

[duke2]

Has anyone tried photon maps for secondary bounces for sorting out the noise? I haven't ever touched them but Mental Ray seems to claim it can do relatively flicker-free GI at high enough settings and it uses Photon Maps for one element of it's GI solution.

I have to say though, the next time I do an animation i'd use some kind of combined ambient occlusion/skylight with HDR thing. The problem with that is of course, it would look completely different to the accompanying stills. Ok scratch that method.