Noise flickering

Corona Corona for 3ds Max Help Required
1

Hello,

I’m using PT+UHD in a few dollie animations but i’m getting noise flickering no matter if i save uhd cache in 30 frames interval and loading them from file.

In the example in attachment (90frames) i’m only using 40 passes (full denoise amount 0,6), maybe i should raise the passes so the noise isn’t perceptible? It was done using “load from file”. The .uhd file was saved using only the 1st frame of the animation. But if i use the middle frame the result is the same.

Thank you! :smiley:

2

That doesn’t look like UHD flickering, that’s more like undersampled noise “boiling”. You can try to make it less visible by locking sampling pattern in render setup>performance>performance settings. Check that box on and see if noise perception is better. It shouldn’t boil anymore, but rather stay in place.

3

Thank you romullus but it is on by default :smiley:

5

Thank you Ludvík! Will try it and update the thread with the new animation when i can.

7

I also realize that, if i use “load from file” and point to an .uhd file generated from any frame of the animation, and then compare any frame with a frame using “calculate from scratch”, the latter has much less noise.

8

Ok, i’ll probably be better off animating DOF in post.

9

interesting… can I get the scene? I would love to look at what exactly is causing it

10

Sure thing Ondra! Just give me a few more days to send it to you since i’ve been quite busy lately.

11

Hey,

has this been solved for you in the meantime?

I’m experiencing the same problem when I use PT+PT for animation.
It was other type of GI flickering when I rendered the same scene with PT+UHD

12

I haven’t tried rendering this scene but i tried other scenes and haven’t had any noise flickering problem. Probably i missed something in my workflow back then. I always precalculate cache prior to rendering and i haven’t noticed any noise flickering.

I’ll try this scene again with the new workflow and see if it solves it.

13

Just a random guess, but flickering even when using PT+PT is typical for scenes where Vray HDRI was used as environment lighting.

14

I think main problem is precompution hdc file.

15

Here are some tests with PT+ PT
I think the reason for the flickering is that I rendered only 2-3 passes to keep the render time low and my frames were still noisy. Despite I used the full denoise, I got the noise flickering effect.

Here is what I got with Pass limit 2

Here is what I got with Noise level limit 6

17

Thanks! I’ll try it out!