I've had objects, usually collectibles, glitch out, but normally they will reappear if you go to map screen and back. Sometimes the cursor itself will glitch out. In that case it is best just to reload the game. I've also seen object get "hidden" in the floor. The object is "there" but not visible graphically. I think they are doing a good job of bug squashing, but there are still many annoying ones. Best option with cameras might be to put them in the Sims personal inventory. I haven't played photography skill though, for the sake of full disclosure.