How can I get smoother slow-motion confetti using optical flow retiming?

[Joseph_H]

I’m trying to get a smoother slow-motion effect on a shot of confetti falling, but even at 60fps source footage, it still looks a bit choppy when I interpret the footage and slow it down in my timeline. Is that just a limitation of my frame rate, or is there a specific way to handle the optical flow retiming in my software to make it better?

[Addison_R]

I tried this last week with confetti at 60 fps. When I slowed the clip to a third speed the motion got choppy and the shapes looked jumpy. I turned on optical flow in the editor and added a pinch of frame blending and motion blur just to test. It helped a little but the confetti still feels off when there is a lot of overlap.

[Emily88]

Its not just the frame rate I think. The tiny pieces move in complex ways and the program can invent frames that look wrong. I did a quick test where I slowed only the bigger pieces and left the tiny bits at normal speed, then merged them back. It looked smoother but not perfect.

[Alexander_J]

Concrete step I took was to pre render a short three second segment after applying optical flow and then slow that render further in a second pass. The pre rendered version was flatter and fewer artifacts. But the long shot still showed gaps on the densest part.

[James_D]

Would splitting the shot into layers and applying different retiming for each layer help, or do you think the real problem is lighting and blur rather than frame rate?