Light fade color not uniform

Support Lighting and Rendering
1

Hi,

I am working on an animation in which the spotlight is slowly turned off.
For smoothing the video I am using Intel AI algorithm.

The problem is that the spotlight color is not smooth, there are visible circles in it. They can be seen in this picture:
fade

Any idea what is causing these circles? Is this the limitation of RGBs?
I’ve tried setting View Transform to Filmic, but the problem remains.

2

I think this is color banding, don’t know much about it but maybe that’s a lead.

You may also try saving to a higher bit depth like Tiff or EXR (16 or 32), but not sure.

edit: and the appropriate man page for 2.82,
https://docs.blender.org/manual/en/2.82/render/output/settings.html#post-processing-panel

3

Thank you @a59303.
I spent some time searching the forum but didn’t find that topic. It sounds like the same problems as I have.

I’ve enabled dithering and set it to around 1.5 and it looks better, but I think it is still not perfect.

This is the original video without dithering:
https://drive.google.com/file/d/1cXmX96I3V43ZJoQW154p0sdVIKC5fTmP/view?usp=sharing

4

You have to change the video to public I think. All in all that is the best I was able to come up with as well, hopefully someone with more expertise can assist. Some things that may help: How did you encode the video? Did you play with the quality settings?

5

Ahhh, I copied the link too quickly and didn’t notice that it is still private. I hope it is ok now.

Yeah, at first I’ve also thought that the reason is video compression, but I’ve then tried with lossless compression and keyframe set to 1 and it was the same.
After that I’ve noticed that even if I render only one frame I can clearly see “steps” in the shade, which were only more noticeable in the video.

6

Hey, sorry didn’t check the thread and didn’t get a notification, I guess I didn’t manually subscribe… The link works. There is something going on though. If I render, the render window doesn’t show it nor does the render tab. If I go into the compositor it shows even without the denoise. Off the top of my head I tried the Render Properties > Film > Pixel Filter > Gaussian and turned it up to 2 and it seemed to improve.

edit: and the relevant man page for 2.82, https://docs.blender.org/manual/en/2.82/render/cycles/render_settings/film.html#pixel-filter