This post was last modified: 2022-04-30, 06:50 by jlg84.

I shot a 405-frame time lapse the other night, and inadvertently changed the exposure value two or three times during the course of the shoot due to silly user error. I have been able to correct this in Lightroom so that all exposures look equally bright, but when I bring the sequence into LRTimelapse it ends up either reverting to the original exposures, or gradually brightening the frames over the course of the sequence (the sequence was shot all during the night, so there was no brightening of the sky toward the end of the sequence). How can I correct this, and prevent LRTimelapse for "re-correcting" it?

UPDATE: I may have figured it out--I manually classed each change in exposure as a new keyframe and adjusted the exposure within LRTimelapse so the Visual Lum numbers were more or less the same. That made the yellow line in the preview window more level, and it seems the resulting Timelapse has a more consistent luminosity.

Basically, what you did is shooting with the "Holy grail" technique. LRTimelapse doesn't care if you did the changes on purpose or not.
The easiest way would have been to just feed the sequence to LRTimelapse, click on "Keyframes Wizard" and then "Holy grail Wizard" which would automatically have calculated the compensations for your brightness jumps, without you having to mess with exposure changes in Lightroom.
Maybe you want to give it a go: you can save your current edits by creating a "Snapshot" (later you can revert to them if you want).
Then do "Metadata / Initialize" to start from scratch. Now do the whole workflow from left to right including the Holy grail Wizard. You can then edit your keyframes in Lightroom without having to take care of these "jumps" because LRTimelapse will already have removed them.

Thanks for the reply--I have done as you suggest, but I'm still seeing little "jumps" in the exposure, which I cannot seem to get rid of. But I'll keep trying it--each time I do a series I get a bit better at it!

Yes, keep pracricing. With holy grail shots it's especially important that you don't blow the highlights when recording at any time. Also set a reference area for deflicker as explained in the tutorials and apply a couple of deflicker passes.
https://LRTimelapse.com/tutorial