Hi all! I've got about 30k photos stored in iCloud which I usually access from my phone or iCloud.com. I happened to open the Mac photos app a couple of weeks ago and have noticed that my disk is now using about 250gb. I don't use the Apple photos app on my Mac as I tend to download them from iCloud.com and import into Lightroom that way. If I delete that file in the screenshot will it free up the space on my Mac and delete the photos I have stored in iCloud? Obviously I want to keep the photos in iCloud and just free up the space on my local disk so a little apprehensive to just delete the file in case all my photos disappear... any suggestions/experience with this?
Your photos won't be deleted from iCloud if you just delete that file, but just in case, some advice that should make it less of a pain to change your mind in the future:
Disable iCloud Photos in System Settings (macOS Ventura)/System Preferences (earlier macOS).
It can absolutely cause some heartburn if you change your mind with the risk of Photos entering a state it doesn't know how to get out of. You're able to create a replacement library, but Photos freezes when attempting to set it as the system photo library, preventing its use for iCloud Photos. The only fix at that point seems to be creating a new user account; even Photos's "recovery mode" doesn't work.
Did it once and it didn't happen. Did it again and it did.