Check out Octonote - https://octonote.com/ https://octonote.com/ it is a webapp I built primarily for D&D DMs to organize their campaigns and share with their g

Check out Octonote - https://octonote.com/ https://octonote.com/ it is a webapp I built primarily for D&D DMs to organize their campaigns and share with their groups but it can be used for other things including what you're describing here. One of the core concepts is a "Book" which is a collection of notes. You can add a note to any number of books and you can share books using a link. To implement what you're suggesting, you could create a book for each group you wish to share with and only add the notes (which would have your images) to the relevant books. What's more is that you could have some books only allow View access and other books to allow Collab so certain users could work with you on those notes while others might only see them.