The applications or the files they access? I have ALL my LR images, catalog, presets etc on an external drive, no issue. LR the application, like Photoshop are stored on the 'boot' drive in the Applications folder.
how do i run LR the application but save to an ext hard drive?
I have an iMac 2017 with a 512 GB internal SSD drive. For photoshop and lightroom work and cataloging can i run photoshop and lightroom off of an external SSD drive?