Motion vectors error

odd one here and not sure if its 2023 specific.
I have a shot where I have done a motion vector track, all good so far.
I only want to render the end of the shot, fr 37 - 73. If i scrub through, the patch sticks where it should, but If I render it, it doesn’t, however, If I render the full length of the shot, it does stick.
Any thoughts?

I’ve seen this before. It is known as the “The Flame Killer” in the beta forum. Only fix I’ve found was upgrading to the lastest non-public version.

so 2024?

I have this issue as well. I think it might only be an issue when using a projector, but I have not really analyzed it closely.


Hi @paul_round,

Alan refers to the Flame version under development (beta) that is not available to the public yet. The situation mentioned by Alan will likely be addressed in a future Flame version.

However, we can’t confirm that this fix will also address the issue you encountered. I recommend you report the problem to our technical support team so it can be investigated and documented.


I had a few moments this morning, and since this screwed me up a few weeks ago, but it stopped being a problem the other day, I thought I’d check it out: The issue arises when the Motion Vector Cache range is different than the render range. @paul_round, if you had cached the motion vectors for frames 37-73, the problem would disappear. Normally I cache and render the same range, so the problem didn’t pop up until I did otherwise, and disappeared when I went back to the usual routine. Tagging @YannLaforest


Nice one Tim!