Flickers and Flashes!

[chris_rw]

Hello! I've been attempting to nail down rendering scenes for a short film I've been working on for the past few years. While I've made some progress on ridding some of the flickering that was incredibly bad in some early tests, it's still not 100% there and my render times have grown to be pretty large.

If you watch the attached animation, you can see that theres still quite a few flickers, especially in the foliage behind the character, but also in places like the top of her skirt. There are also some strange flashes. In the first 10 or so frames, you can see a burst of light that hits her pigtails for one frame; at a larger resolution, it looks like the rim light gets 10x brighter.

Some of the things Ive already done to get to this point are: Ive raised my Irradiance settings up pretty dramatically, this seems to have fixed a large amount of flickers. I also converted all the maps in the scene to VRayMtls, which seemed to help the render times.

The plants are planes with opacity maps. Most lights at this point are using VRay Shadows. Im wondering what I can do to get a little better results. Is V-Ray the renderer for me (will it allow me to get good, clean renders for my film)? Im open to suggestions!

Thanks for any help I can get!

The test animation is here: http://www.cwanimation.com/Nerm01.mov

The animation test is pretty stripped down...no motion blur, DoF, and other pretties.





www.cwanimation.com

[trixian]

Hi.

Looks very nice I must say.
I suggest you split your scenes up into 2 categories: Animated, and Static.
Start with your Static parts, and precalculate lighcaches and imaps for all static objects. Then render all animated objects with the most important\affected static items as mattes for shadow stuff and so you still get the right gi solution from the matte objects. Here you could even render qmc\LC for the character alone to get that extra punch in gi detail and have it flicker free at the same time. When rendered alone, It usually doesn't take too long.
You might even render out effects such as volume light separately to lessen the burden on the main renderings.

Looks to me that with those settings you have, you might as well render with the 2universal settings2 (do a quick search on the forum for more info on this), and at least get it flicker free.

I presume you don't render your static background every frame for locked off cameras, as that would be silly. Better to edit it in post.
Sometimes, just rendering small animation loops for animated props, matted out for comping can suffice. Then just chain them together in post to get some semi-natural movement going. (This does not always work that well though).
If you were to try to render this with any other renderer, you usually have to adhere to the same basic work flow, unless you have unlimited cpus and memory

Hope this helps a bit.

[tammo]

i agree.
for such a complex scene split up in layers or go QMC.

[DaForce]

Aside from the problems your having.. mate that is one sexy render.. the tree in the background.. the leaves are they just mapped planes or is it all mesh.

Love the render and its details. whats it from (if your able to tell)

As for your problems. the suggestions above would be a great start. In the mean time try dropping your rQMC noise threshold to 0.005 and see if that helps at all. Your Ir map settings seem really high.. somewhat over kill i would *think*

But certainly IRmap is NOT good for animation objects and lights.. never really has been. Vlado has made up a special feature in the newer (not released) RC builds that make IR a more possible option for animation it reduces the flickering a Huge amount.

[studioDIM]

Something that popped to my eye is that you're using adaptive subdivision as AA method.
Try and switch to QMC, as you (will) have DoF, MoBlur and glossies, as that will speed up the renders by a margin.
It will also insure you'll be able to control the primary QMC pass a bit better through the AA sampling (check out Vlado's post on "universal settings" to understand the concept)

I would suggest, as it's been suggested before, to go QMC for the primary GI pass, as you'll get a similar, if not better, quality to your current IRMap settings, for a comparable render time (your sampling for the IRMap is indeed extremely high).
I would avoid interpolated methods at all in a scene like this, as the main character is prominent in the shot, and moving.

It is a really nice subject, btw, and very nicely accomplished, so far

Lele

[priad]

indeed very nice btw.
show us the end when ready!!

[percydaman]

i concur with everything suggested thus far. Irradiance maps are for architectural walkthroughs. If it were me, I'd just bite the bullet and switch to QMC. With those irrad map settings, I can't imagine they are going incredibly fast anyways.

[dimo]

Very nice.

My two cents would be:

1. split up into static background and moving elements.
2. Render the static background with prerenderd IRMap
3. Write Vlado an email that describes the project and that you would like to test the new Animation GI Engine.
4. Render the moving elements with RC5

Best regards,

Dieter

[chris_rw]

Love the render and its details. whats it from (if your able to tell)

Its from an animated short I've been working on for a few years called 'The Chronicles of Nerm', you can see more renders of characters/sets at http://www.cwanimation.com/nerm2gallery.htm . It will be a sequel to an older college animation I did a few years ago that you can see here: http://www.sharecg.com/v/480/animati...?division_id=2

Thanks for the advice so far, I have a lot of testing to do now!

[ene.xis]

well i sure remember that!
top notch!
i m looking forward to see this finished! its looking very-very promising!

[DaForce]

Love the render and its details. whats it from (if your able to tell)

Its from an animated short I've been working on for a few years called 'The Chronicles of Nerm', you can see more renders of characters/sets at http://www.cwanimation.com/nerm2gallery.htm . It will be a sequel to an older college animation I did a few years ago that you can see here: http://www.sharecg.com/v/480/animati...?division_id=2

Thanks for the advice so far, I have a lot of testing to do now!

Excellent, looks fantastic.

Do be sure to post the final animation when done