Has it ever been answered why Naomi had Desmond's photo.?

After all, it was Penny's property and why would Charles Widmore expect Desmond to be on the island??

It was never answered directly, but the picture was a scanned image, the freighter is Daddy Widmore's he knew when she would be out of the house, sent someone in to scan the pic. He probably knew Des would be on the Island because he sent him their, click the real bad guy link in my sig, thinking perhaps there is no way Desmond would stop pushing the button, wanting to show Widmore that he was not a coward, it's an act of I'm grooming you to do what I want but you just don't know it ala Christian and Jack, Christian was grooming Jack to be the one who led to the downfall of of the Others. For the people who will freak out about the wording of the above and think it's a spoiler, it isn't it's a guess.