Preview image teeny tiny in Develop mode and external hard drive going crazy

Report · Jul 21, 2025

I am experiencing some strange behavior with Lightroom and an external hard drive. I am on a Mac Studio. When I import photos into LR classic the external hard drive starts going crazy clicking away like it would if you were to drag a bunch of huge folders into it. But my settings are such that all my imported photos files are on my desktop hard drive as well as my catalogs. Nothing is going onto the external hard drive but something is triggering it to go off. (only later in my workflow do I drag the folder onto the external hard drive later after editing the photos). Eventually after 30+ minutes it settles down (importing 200 photos). But here is the problem, while the hard drive is going crazy I will edit the photos in LR and often will ‘open as layers in photoshop’ multiple files into a composite and work on it in PS, then flatten and bring back into LR. But now back in LR when in Develop mode the photo is teeny tiny on the screen, just a little dot. It will not show preview full screen in Develop mode, unless I’m in crop mode (and the crop mode is all funky). So I can’t further develop the photo until the external hard drive catches up doing whatever the hell it’s doing. If I wait for the external hard drive to finish whatever it’s doing then I don’t have any issues, but this means I have to wait around for 30-60 minutes after downloading, much longer for bigger shoots. I shoot real estate so I need to edit photos right away. Why is this external hard drive giving me problems when as far as I can tell it should have nothing to do with what I’m doing. Another option is to turn off the hard drive and then no problems, but thats kind of a pain since I am constantly have to pull files off it from past shoots so I would be turning it off and on constantly.

Report · Jul 21, 2025

I am experiencing some strange behavior with Lightroom and an external hard drive. I am on a Mac Studio. When I import photos into LR classic the external hard drive starts going crazy clicking away like it would if you were to drag a bunch of huge folders into it. But my settings are such that all my imported photos files are on my desktop hard drive as well as my catalogs. Nothing is going onto the external hard drive but something is triggering it to go off. (only later in my workflow do I drag the folder onto the external hard drive later after editing the photos). Eventually after 30+ minutes it settles down (importing 200 photos). But here is the problem, while the hard drive is going crazy I will edit the photos in LR and often will ‘open as layers in photoshop’ multiple files into a composite and work on it in PS, then flatten and bring back into LR. But now back in LR when in Develop mode the photo is teeny tiny on the screen, just a little dot. It will not show preview full screen in Develop mode, unless I’m in crop mode (and the crop mode is all funky). So I can’t further develop the photo until the external hard drive catches up doing whatever the hell it’s doing. If I wait for the external hard drive to finish whatever it’s doing then I don’t have any issues, but this means I have to wait around for 30-60 minutes after downloading, much longer for bigger shoots. I shoot real estate so I need to edit photos right away. Why is this external hard drive giving me problems when as far as I can tell it should have nothing to do with what I’m doing. Another option is to turn off the hard drive and then no problems, but thats kind of a pain since I am constantly have to pull files off it from past shoots so I would be turning it off and on constantly.

By @Whit Richardson

Hello <Spam removed>
It sounds like Lightroom is accessing your external drive during import due to background catalog previews or smart previews being stored or referenced there. This can cause excessive disk activity and delay rendering in Develop mode, especially if the drive is slow or fragmented. To fix this:

- Ensure your catalog and preview files are stored **only** on your internal drive.
- In Lightroom Preferences > Performance, disable “Use Smart Previews instead of Originals” if not needed.
- Check if your external drive is listed in the Folders panel and remove any unused references.
- Try ejecting the external drive before launching Lightroom if it’s not needed immediately.

This should prevent Lightroom from unnecessarily pinging the external drive and improve responsiveness during editing.

Best Regards,
Amy Batson

Report · Aug 21, 2025

Hi @Whit Richardson, checking in to see if the suggestion helped or if you are still running into this issue? In addition to what was posted, here are some things to check:

External Drive Activity: Even if you're not importing to the external drive, Lightroom may still access it for previews, cache, or catalog references. Check your catalog and preview file locations in Preferences > General and File Handling. Also, consider disabling Spotlight indexing for the external drive to reduce background activity.
Tiny Preview in Develop Mode: This can happen if Lightroom is struggling to render previews while the system is under load. Try building 1:1 previews manually via Library > Previews > Build 1:1 Previews, and clear the cache under Preferences > Performance. Make sure Lightroom and macOS are fully updated.
Performance Tips: Increase Lightroom's cache size to 50–70 GB, ensure you have at least 20% free disk space on your internal drive, and restart your Mac before large imports to free up memory.

Let me know if any of these help or if you still encounter this issue. I hope these suggestions help! ^CH

Report · Aug 26, 2025

Hi Claire,

Thank you for the reply. Unfortunately the problem is still occuring. All previews, cache, and catalogs are on my main working drive so it can't be that. I've gone through all my LR settings and Preferences menus but I just can't figure it out. Just now I added two 5.8 MB jpeg files to a LR folder that is located on my desktop and the external hard drive has been suddenly spinning and clicking away like crazy for 15 minutes before stopping. This makes no sense whatsoever and is a real conundrum. I've got a Mac Studio M1 Max 64 GB so I'm not under powered, and all software is up to date. Another interesting bit of info is that I have two different catalogs that I go back and forth from depending on my shoots. This problem is not happening with the other catalog. All catalog setting between the two are the same. Again, neither the photos or the catalogs or anything is located on this external drive but somehow it's going crazy when importing to my main drive. One thing I have not tried is disabling Spotllight indexing but this doesn't seem like it would be an issue. For now I have resorted to just ejecting the external drive when it's not needed but it would be nice to not have to since I refer to this drive often for requests for photos from past shoots. Maybe the problem is not with LR but the external hard drive? I suppose I could replace the hard drive and see if it solves the problem.

Report · Aug 26, 2025

Hi Amy, thank you for your reply. I have responde to Claire who chimed in after you, see below in the thread. So far the only thing that works is ejecting the external drive, but it's a work around and not ideal.

Report · Aug 27, 2025

When I uncheck 'Automaticly write changes into XMP' in the LR Catalog settings it doesn't seem to matter, it keeps doing it. When I try to eject the external hard drive while it's busy (ten minutes after importing 7 drone photos) it gives me this pop up.