Premiere Pro export light glitch

[Rebekah23814953hs34]

I don’t know why but when I export my video the end result has a bunch of these glitches with light. It’s fine when I edit but once I export its a mess. I’ve tried different formats, different presets, I’ve tried rendering, turned down saturation in lumetri scopes…what’s going on?

[Steve Griffiths · Accepted solution]

Have you applied a speed/duration change to this shot? And if so, are you using 'optical flow' as the time interpolation method?

This looks like a classic case of optical flow artifacts, caused by the moving and flashing light ... something that optical flow doe not handle well.

Change the interpolation for this clip to 'frame blending'. It won't have as smooth motion but it also won't have the artifacting.

[Rebekah23814953hs34]

That worked. I literally screamed. Thank you.

[Steve Griffiths]

Great. One thing you can do before removing optical flow from every shot (if you want to keep the nice optical flow slomotion) is preview render your sequence before exporting. Then play back the sequence.

That way you can see if optical flow is causing issues on some shots before you export and only need to remove optical flow from the problem shots.

[Rebekah23814953hs34]

Yeah I'm noticing that the flow isn't as great. Would that be fixed if I rendered first or is that just the cost of not using optical flow?

[Steve Griffiths]

Yeah, optical flow is pretty nice when it works.

I've gone to great lengths sometimes to combine optical flow and then switch back to frame blending only on problem shots. i.e. layering up problem shots (layer 1: Optical flow, layer 2: frame blending - and masking out the problem areas and using the flame blending layer.

Or you could even put cuts on your problem shots and switch to frame blending for the few frames where optical flow fails. That can *sometimes* work.

Preview rendering first just means you can then watch the program through and only turn optical flow 'off' when necessary.

[Joost van der Hoeven]

I too think you have Optical Flow turned on. Switching to on of the other interpolation modes will fix this issue.

[Rebekah23814953hs34]

I'm going to try that now thank you. Am I doing this for every clip?

[Christian.Z]

This looks like an optical flow issue

[Richard van den Boogaard]

Can you please confirm whether or not this was indeed an optical flow issue? Otherwise, if you provide us additional information we can try and help you out...

Thanks.