Subtract subject from mask not working properly

Report · Mar 10, 2025

I haven't found a previous post about this so: I have the latest version of Lightroom (v8.2) on Windows 11
Pro, and since the last update of LR I have issues with subtracting from masks. The issue occures when I first try to subtract from a newly added mask - it just adds the thing (I'd like to subtract) to said mask instead of subtracting. If I go to different mask, or go back to Editing, and then go back to said mask, I can sometimes subtract, but sometimes I needed to repeat going out and then back in. And while making a video of this problem, I just noticed, that when I click on "subtract", the "add" gets selected, but if I double click on "subtract" it is selecting that one. Nonetheless, it is kind of inconvenient, so I would be very very grateful if you could look at the issue (: I might also add, that my storage is full in LR, if that counts in finding the root of the problem.

Thank you so much! I also attached videos of the issue.

Report · Mar 11, 2025

Hey, @czeglegraphy365. Welcome to the Lightroom Community. Thanks for adding the video; it helps.

We've tried to recreate this but with no success. Has this started to happen since a recent update? Does this image have any global adjustments applied to it prior to the masking workflow?

You can try resetting Lightroom as a primary step in troubleshooting this.

1 - While holding down the ALT + SHIFT keys, launch Lightroom from the Creative Cloud desktop app.

2 - Select 'Yes' when prompted to reset Preferences.

Let me know how it goes. Thanks!
Sameer K

(Type '@' and type my name to mention me when you reply)

Report · Mar 11, 2025

Hi @Sameer K,

Wow, thank you for such a quick response, I really appreciate it! I've done as you've adviced, and it seems to have fixed the problem, but I will keep checking and will come back, if it re-occures.

Regarding your questions:

- I honestly believe this has started after the latest update, but I cannot pinpoint it to an exact date. The update was 26 days ago, and I deifinitely had this issue for a couple of weeks now.

- The image in the videos had no prior edits, however I usually make mask after basic editing, so I don't think this impacts it in any way, or at least I found no connection.

Thank you so much again!

Report · Mar 11, 2025

Hi again @Sameer K,

And just as I've sent my reply after testing it with a couple of photos without any problem, it has done it again 😄

It happened with a photo I've done basic edits already and I've already made a "subject" mask too. Then when I went to have a "background" mask and subtract the subject, it happened again.

Let me know if you can think of any follow-up questions, and I hope I can answer or make a video.

Report · Mar 12, 2025

Thanks for the great news & the not-so-good news.

It'll help if you find a repeatable pattern and record it in a video, too. If possible, export the impacted image as DNG so that it includes the edits and masks. Please upload the video and the DNG sample to a cloud file host like Google Drive, OneDrive, Dropbox, etc., and share a public link to the video with me in a direct message on my profile.

Thanks!
Sameer K