I have it in my contract that the model cannot have copies of the reference photos. I have no idea what they plan to do with them, and it has been said, it devalues the art and there's no reason for them to have it. I will let them have a copy of a photo that I
don't use just to be a nice guy.
Several people have personal websites. They could decide to post it on their site where anyone can view it, and people will compare it to the artwork. Artists may use "other people's photos" (they're down wit OPP) which diminishes the value of your art, if not making it valueless. I won't post reference photos for similar reasons, plus I have an agreement with the model that I won't do so. It makes them feel better that they won't eventually have their face imposed on a porn site.
I have a paper shredder which is where the photos go after I'm done with them.
Now a commission I feel is different. I have given clients the reference photos after reminding them that I am not God, and there will always be discrepancies. For my personal stuff, the pics are mine, mine, all mine.
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