Backing up photos onto external hard drive
Hi all! I'm trying to set up a system for backing up my photos. I have two external hard drives. One I use for time machine and back up my entire computer. I'd like to back up ONLY the photos onto the other hard drive. And I'd like it to happen automatically whenever I add photos to the photo folder on my iMac. Is this even possible? And if not, is it possible to set up Time machine to do a different back up than what I have set up in case my computer fails? i.e., I want to keep my back ups in case of a failure. But I'd like to also have JUST photos backed up to my second external hard drive. Clear as mud?
Thanks!
PS I'm running 10.15.6 on my 2017 27" iMac. Thanks!
PPS I don't currently use the Mac Photos software, but I'm open to it if it helps me with this process.
New 27" iMac