Ideas
I'm having the black photos issue as well! Basically any photo that gets stored in a storage box (like the ones from Eco or the storage box), the keepsake box, or in those digital picture frames from Moschino pack and the Forever Friends event will guarantee turn all of my photos black. Every single one. Its kind of a bummer because I really like storing my extra photos so that I can pass them down to family members for their homes.
I have tried this with mods and without mods. It happens in brand new saves, as well as when I load an older save. The black photos seem to appear after saving the game and exiting. The moment I load the save again? The photos are black. I even tried the 'save' and then 'exit without saving' method. Still turns them black :(
So I've just been uploading a small room to my gallery library with my photos as a precaution or avoid taking photos because of this bug.
I really hope this is fixed soon because its so soul crushing for a legacy player. I've seen someone on reddit who lost over 30 generations worth of family photos from this bug.