P: Auto-Stack By Capture Time is extremely slow

[johnrellis]

Auto-Stack By Capture Time is extremely slow in my LR 9.3 but is nearly instantaneous in LR 8.2.1.

Details: 

In LR 9.3 / Mac OS 10.15.5, I selected 1185 photos and did Photo > Stacking > Auto-Stack By Capture Time. I got the spinning beach ball for over two minutes and LR was unresponsive before the dialog finally showed how many photos would be stacked:



In LR 8.2.1, I selected mostly the same photos (1170), and Auto-Stack instantaneously showed me how many photos would be stacked, with no spinning beach ball.

Something broke since LR 8.2.1. Auto-Stack should be just a simple sort and linear scan of the capture times of the selected photos, so the behavior in LR 9.3 is clearly a bug.

See here for the original report by another user on Windows:
https://community.adobe.com/t5/lightroom-classic/auto-stack-by-capture-time-causes-lightroom-classic...

[drtonyb]

I'm not seeing this problem with my LrC 9.3. Auto stacked 384 images which displayed the number of stacks almost instantaneously. Selected Auto stack on 1185 images and this showed the number of stacks in 2-3 seconds. Tried 9499 images and that took 33 seconds. Windows 10.

[johnrellis]

Interesting, my two main catalogs don't exhibit the problem. But my small test catalog does (Mac), as does the catalog of the person originally reporting the problem (Windows).

[Sunil_Bhaskaran]

Thanks, John.
We could reproduce this issue.
We are investigating.

Thanks,
Sunil

[cjonesmn]

This feature does not work well because the timing between stacks isn't always consistent OR the same minimum. A much better solution would be to add the ability to define how many photos per each stack... not by capture time.

[johnrellis]

This thread is about Auto Stack running very slowly.  Please post your feedback on this other thread, which is more to your point:

https://feedback.photoshop.com/conversations/lightroom-classic/lightroom-classic-better-auto-stackin...

[Rick Spaulding -]

Greetings,

Updates for the Adobe Photography Products were released on 10.20.2020 that include fixes for these issues. Please install the most recent update and confirm that your issue is now fixed. Please let us know if you encounter any issues.

Thank you for your patience.

[johnrellis]

The issue no longer occurs with my test catalog, thanks.