Flashing in the sequence

[yi_xiang]

Hi there,

After trying Vantage for a while, it feels really useful and the rendering is so fast. But when i used the scene from "Building Utopia", I found that there are lots of flash in the sequence I rendered. it almost flashed everywhere in every single frame, especially in some specular, reflection roughness and some self illumination area, the flash i think is unacceptable.

Though I've tried to improve the samples to 10000, nothing seems to have changed, then i can not find any options to fix this problem.

I post two images bellow, it just one of the flash and there are also plenty of flash in sequence. So, what should i do to kill these flash?

Happy new year.

[npg]

I was going to suggest that this is caused by the denoiser as discussed in other recent threads, but it looks like these are raw images. Are they? If the denoiser is off, then this must be a "firefly" artifact boosted by the Bloom post-effect. If you turn off Bloom before rendering the sequence I expect you will have a single bright pixel there, which would be somewhat better but probably still quite noticeable. Now why would the pixel be so bright - it might just be the perfect angle to reflect the Sun or it might be a shading bug... We'd need to investigate to find out. All this applies if it is a raw image - otherwise it must be a denoiser artifact.

[yi_xiang]

I was going to suggest that this is caused by the denoiser as discussed in other recent threads, but it looks like these are raw images. Are they? If the denoiser is off, then this must be a "firefly" artifact boosted by the Bloom post-effect. If you turn off Bloom before rendering the sequence I expect you will have a single bright pixel there, which would be somewhat better but probably still quite noticeable. Now why would the pixel be so bright - it might just be the perfect angle to reflect the Sun or it might be a shading bug... We'd need to investigate to find out. All this applies if it is a raw image - otherwise it must be a denoiser artifact.

Yeah, i also considered the cause of denoiser or glare effect, but as you see i set the denoiser as 10 so the images looks like raw images.
About Bloom, i tried to render another series of sequences and increase the Threshold of Bloom, i post images bellow.

You see, I numbered the pictures in frame order. Carefully look at the result in the reflection of the glass, the bright pixels which are the reflected of street lights seems to appear randomly. Obviously these pixels didn't reach the threshold of Bloom, but because their positions are uncertain and random, and this situation happened in most places in the image, so the entire sequence still seems to be flashing all the time. It is imaginable that if these pixels reach the threshold of Bloom, it will flash terribly.


I started to wonder if it is because the Vantage itself does not have a "fly-through" or other modes like Vray renderer, so there will be a large number of pixels with uncertain positions in the reflection and highlight areas. I think two adjacent frames should not have such a big change.

[npg]

The only way to remove bright denoiser artifacts would be to set the denoiser to 0 (or "keep denoiser = off" in the sequence dialog). Even at a low slider value the blending is performed with preference for the denoised pixel if it differs a lot from the raw value.

[yi_xiang]

The only way to remove bright denoiser artifacts would be to set the denoiser to 0 (or "keep denoiser = off" in the sequence dialog). Even at a low slider value the blending is performed with preference for the denoised pixel if it differs a lot from the raw value.

I followed your suggestion and turned off the denoiser completely. It has indeed improved a lot, and I also saw a lot of material details that I can’t see when the denoiser is on.

Thanks.