I recently was notified by my MacBook Pro that it was almost full (storage). I was shocked as I store all my LR/Photos on an external hard drive from day one. After looking into it further, it appears that the largest memory consumer was "Lightroom Catalog Previews.lrdata" - using 83GB of data. I did some reading up and found that my preview settings were defaulted at a "higher quality" setting and therefore large files. I corrected the setting. I understand that will prevent for the future, but what can be done now to the existing file/folder to free up some storage? What exactly is this "folder" and can it be deleted? Any advice is appreciated - thank you!
Yes it can be deleted. LR will generate previews as required. You may need to scroll through a few gray thumbnails when looking at an old folder but it saves a lot of space.