I know that this sounds odd, but I strongly recommend that you never set your keys down in public where they can be photographed. There is a company out there now where you can send a photo of both sides of a house key and they will mail you a new key for it. The company doing it does not feel that it is creating a security risk but most of us in the industry would disagree with this. They do not require any ID or proof that the house or apartment or whatever is actually yours so someone could photograph your key and then receive a duplicate of it, cut by code in the mail in a few days! There are far too many key ring options available to you for you to ever need to set your keys down in public.