I created an account to ask a question, but saw this and need to answer.
RAID (in any form) is just a protection against hardware failure. It is NOT a backup against disaster! If there is a fire, robbery, hacker, ransomware, delete-button, etc, YOU WILL LOOSE YOUR DATA!
For your photos and other irreplaceable data, GET A BACKUP SERVICE! Make sure your data is stored offsite, safe from natural disaster and software issues.
Personally I'm partial to CrashPlan (which happens to be a docker container for unRAID I saw) but there are several other good ones out there as well.