Lightroom Classic extremely slow export

[richard.1604@gmail.com]

After M1 MacBook Pro Upgrade to Tahoe, Lightroom Classic is running extremely slow, 3 HOURS to export 42 images.

My workflow has come to a halt 

Help

[Moved from ‘Bugs’ to ‘Discussions’ by moderator, according to forum rules. You cannot file a bug report for Lightroom Classic 14.5.1 on MacOS 26, because Lightroom Classic 14.5.1 is not supported on that version of MacOS.]

[JohanElzenga]

Every year we see the same thing. As soon as Apple upgrades MacOS (or even when Apple releases a public beta), people install it without waiting for software like Lightroom and Photoshop to be certified for that version of the OS. And then they complain about compatibility problems. I'm not saying that your problem is caused by this, but it definitely could be and the answer is that you will have to wait until Adobe brings out an update that is officially supported.

[Olly Bowman]

Yes, but the reason there are beta versions is so that pre-release issues can be found, and developers can get their software working properly. Adobe have had three months to work with the beta, or possibly longer as they are such a major developer. 

[Conrad_C]

You will find that many developers, not just Adobe, choose to not declare compatibility on day one of the .0 release of a major OS upgrade. The reason is that in the past, some developers did declare compatibility based on months of testing with OS pre-release builds, but new bugs crept in between the last GM and the actual .0 release and these developers got burned when customers started calling and saying “you said it was compatible and there is this problem.” After that happened a few times, many developers today will not declare compatibility until they have had time to run their full test suite on the actual .0 release.

This is probably why the official article “Adobe apps compatibility with macOS” doesn’t mention macOS 26 yet, but I don’t work for Adobe so I don’t know the real reason Adobe has no information about macOS 26 yet.

[Conrad_C]

After M1 MacBook Pro Upgrade to Tahoe, Lightroom Classic is running extremely slow, 3 HOURS to export 42 images.

By richard.1604@gmail.com

There should not be any reason why Lightroom Classic alone would take 3 hours to export 42 images, so there might be something else also using the processor and competing with Lightroom Classic for processing time. There is some detective work you can do to try to find out where the real problem is.

When exporting, open the app Activity Monitor (it comes with your Mac, in the Utilities folder) and click the CPU tab. Click the heading for “% CPU” to sort the list by the processes using the most CPU. During an unusually long export, look at which processes are at the top. Is the top process Lightroom Classic, and what is the % CPU used? If the process using the most CPU is Lightroom Classic then maybe there is a problem with that software. But if the process using the most CPU is not Lightroom Classic, you may have identified another process that isn’t yet fully compatible with macOS 26 and is using too much CPU.

The GPU tab may provide similar feedback. Also, check the Memory tab and report what the Memory Pressure is during exporting, and if any processes are using an unusually high amount of memory in the list.

[Olly Bowman]

I'm also seeing slow performance, editing photos is painfully slow on my M1 Max MacBook Pro to the point of being unusable, and exporting does seem a little slower. There are also several UI issues when using Lightroom in full screen mode. 

I get that there is no official support of Lightroom for macOS 26 but this level of performance is really unacceptable after months of a beta release.

i had to stop editing yesterday evening because the poor performance was really frustrating. Several seconds on occasions before a photo would be loaded. 

[dj_paige]

I'm also seeing slow performance, editing photos is painfully slow on my M1 Max MacBook Pro ...

Please start a new thread and explain your problem in detail, and people will try their best to help you. However, you should not continue this topic about editing slowness in this thread, as your problem is clearly different than the original topic about exporting.

[Olly Bowman]

I'm not looking for help, i'm adding to the post which is titled 'Lightroom Classic extremely slow" and is in the "discussions" forum. I'm simply adding to the discussion about Lightroom classic being slow.

[dj_paige]

Slow exporting is the problem discussed in the orignal thread, discussing slow editing does not belong in this thread. Your discussion is fine and welcomed in this forum, but not in this thread because you have a different issue.

[Olly Bowman]

The thread is literally called "Lightroom classic is extremely slow"! Who gave you the right to decide specifically what is and isn't discussed in this thread. 

[Rikk Flohr: Photography]

@Olly Bowman 

Please follow @dj_paige 's recommendations. Their experience in this forum is valuable, and you will achieve better results by following their advice. 

[Olly Bowman]

I'm not looking for results, i'm simply joining the discussion to backup the original posts comment that Lightroom is running slow after upgrading to MacOS Tahoe. I verified that image exporting felt slower and also image loading was slower. I would appreciate it if you could explain to me what the problem with my comment is, as i do not understand the issue in what is a discussion forum.

[Conrad_C]

There is another thread here where someone linked to a Reddit thread with a potential solution for extreme slowdowns for Mac apps in general:

https://www.reddit.com/r/MacOS/comments/1no872w/psa_macos_26_bug_leads_to_performance_issues_in/

I haven’t personally tried it, but if that fix helps you, then that means the bug is in macOS 26 Tahoe.

The reason I haven’t tried it is I always wait for a while (often months) before installing a new OS. I prefer to wait out all of these issues until Apple and others release their bug fix updates. macOS 15 Sequoia continues to be very stable for me.