This post was last modified: 2021-07-22, 01:19 by Steve.

I believe others have run into this too. I don't know why/how it occurs but a solution seems fairly simple so thought I'd share the problem and the solution.

When I want to have some frame motion in my time lapse I know to use 5-stars in LR and to set my crop to 16x9, the same as I will use for output. My starting point is to select first frame and set it's aspect ratio to 16x9 then sync all frames in the time lapse to that crop (only sync the crop settings). I then select the frame where I want motion to start, giving it a 5-star rating; the last frame I want motion to stop, give it a 5-start rating; and any frames in between these two are then adjusted accordingly and given a 5-star rating where sizing or motion changes.

I then go back to LR Timelapse and go through the second row on the Visual Workflow. After Reading the metadata back into LR I'm ready to export, but I get an error that there are different crop aspect ratios (see attached screen shot). I think this is something that is occurring in LR Timelapse, not LR.

What I've found as a simple solution is to select the first frame, then all frames and sync just the aspect ratio, (see attached screen shot) not the entire crop as that will reposition all the frames to the same crop location and size as the first frame, which will change any size and frame motion. Once this is done LR no longer gives me the different crop aspect ratio found error.

In my current project my first frame motion was on index 119, but the crop aspect ratio occurred on index 8, which was static from the first frame, and as mentioned above the entire project was initially synced with the crop and aspect ratio of the first frame. So it seems to me the issue is occurring in LR Timelapse.

Hi Steve, thanks for sharing your findings.
I think the problem might happen in some very specific cases, where the motion calculation leads to slightly different crop aspects ratios due to Lightroom always cropping to full pixels. LRTimelapse tries the best to calculate those animations, but as I always said, Lightroom is not really designed for this kind of things. Every decent video editor will crop on a subpixel basis to get the smoothest animation, this is just not possible with Lightroom.

Another thing you should be careful with is to not place any of the crops on keyframes directly on the edge of the frame. This also might lead to skewed crops in the transitions.

The warning happens, if the exporter finds that kind of rounding errors or other anomalies with the crop, to prevent choppy results or encoder errors due different aspect ratios.

Fixing it like you do might work, but more likely it will just get rid of the warning and still lead to choppy videos.

My recommendation would be to do very simple and slow animations only (too much crop movement will distract the viewer anyway) if you really want to do them in LRTimelapse.

Personally, I prefer to export the full frame and do any ken burns animations later in video editing, because video editors do that smoother. Also at the time of video editing I will know much better how to do an aesthetic movement because I will also be able to consider the adjacent clips then.

Hi Gunther, thanks for addressing the attachment issue, I was able to attach the screen shots to my Post. Also, thanks for the reminder of LR and full pixels, if I knew, I forgot. To maintain resolution in the video I've chosen to do my reframing in LR. If I were to do them in my video editor I'd need to start with a higher resolution, 3k or 4k, my system and software don't play well with 4k, although I may give that a try just to compare the workflow, might even encourage me to upgrade my system that I've been meaning to do for some time now.

Hi Steve, I understand - but especially with such low resolutions like 1080p, every pixel will in comparison be 4x as big as with 4K that means, that any jitter you get due to cropping to full pixels, will be much more present than if you work with higher resolutions.
Bottomline: the higher the resolution that you work with, the better the results if you do ken burns animations in LRT/LR.