When I got married (20+ years ago), my dad painted (oil panting on canvas) of our engagement photo that our photographer took, and wanted to display it at our wedding reception. I asked our photographer at the time if it was ok, and he mentioned that his painting was considered "deriavitive work", so that he wasn't violating his copyright. Yea, I get he's not a lawyer, and this is just a single instance, but I hope the outcome for Kat Von D, especially since she didn't get paid for the tattoo comes out the same.