You may have noticed that when you’re exiting Lightroom, sometimes the software asks if you want to make a backup of the catalog. You can actually adjust the settings for how often it prompts you via the General tab of the Catalog Settings. Some would argue that you should set it to prompt you each time you exit. That’s more than I need, but I do like a once-a-week backup, or thereabouts.
Why not back up every day? Because Lightroom makes a full copy of your catalog information (not the image files themselves, but the catalog data) every time you back up. And these can get large, especially when you consider that today’s backup contains everything in yesterday’s backup, plus any additions. My catalog, for instance, is over 4 GB each time I back up.
This all means it doesn’t take long to accumulate a whole ton of file space dedicated to backups that are largely redundant. The most recent backup, after all, contains the most recent version of your catalog. So, as long as you save it and maybe a few other recent ones (today, last week and last month, perhaps), you’re plenty covered in case something goes wrong.
I wish Lightroom would prompt me to throw out my old backups to save disk space, but until they do, I’ve got to do it myself. You should, too.
Start by finding where Lightroom stores those backups. By default it’s in a folder called Backups that’s kept with the rest of your Lightroom files. For me, that’s in my Pictures folder. If you can’t find it, open Lightroom, go to the Catalog Settings folder, and under the General tab, click the dropdown menu to set Lightroom to back up the next time you close the program. Then close the program and it will show you where the backup is kept when it displays the prompt about backing up.
When I click on my Backups folder and check to see the file size, I see that I’ve got more than 100 GB of backups on my hard drive—not something I need.
So outside of Lightroom, in a plain old Finder or File Manager window, I simply click and drag to select a bunch of old backups (they’re organized and labeled by date, so it’s easy to tell what’s what) and leave a few new ones in place. Throw them out, empty the trash and, voilà, I’ve cleared 100 GB off of my hard drive. It’s just that simple. And because I’ve kept three recent backups, I haven’t compromised my catalog’s integrity at all.