Optical Flow reacts weird in between cuts and shots

[PeterVerhoeven]

Whenever I use a slow motion with Optical Flow in Time Remapping or with a speed/duration change (right click) it reacts very weird with cuts in between shots. Every time I activate the Optical Flow on 2 shots that follow each other the cut is morphed and creates this weird effect as if Premiere is trying to cross dissolve the 2 shots instead of just cutting to the second shot. I've tried multiple edits and settings, but it keeps happening. Maybe I missed something or i'm not doing it right. Anybody have the same problem?

[Jim_Simon]

Is the effect applied directly to the clips?

[PeterVerhoeven]

Yes, to each clip or shot individually

[Jim_Simon]

I can't reproduce the issue here.  It's working as expected.

[jphilip75]

Optical flow should have a "scene change" detection that could be adjusted.

Optical flow also goes all over the place when a sudden lightning change takes place. For exemple It's a nightmare to use OF with clips also containing photoshoots because of the flashes from the camera. The only way I have found to fix this is to edit and cut the 3-4 frames that goes all over the place and set it to "interpolation" instead of "Optical flow". Very tedious and long work when you can have several douzens of flashes in your sequence.

So yes Adobe should considering adding scene and lightning changes detection in Optical Flow.

[chrisw44157881]

i made a optical flow template in AE with scene detect(open source) similar to AE's magnum edit detector for optical flow. dunno if this helps.

[jphilip75]

Lighting and not lightning. Sorry, english is not my native langage.

[Hiddenpictures Ltd]

I had the exact same issue with PP CC 2017 (and also 2019 when I converted the project to the later software).

OF seems to be a bit fragile at low lighting and if you slow the footage too much.

This is what ADobe's official tip is:

The best results often come at 50% speed or higher, because the interpolation rate in that case is 1:1 or less.

Moral: don't make it work too hard.

[Huge Larry]

I saw this issue today in Premiere 22.5.0, which is the latest version as of this writing.

My workaround was to put a manual cut in the clip right at the scene change, then tweak the start and end points a bit so the interopolation didn't span across the scene change.