Firstly, what physical evidence would, for want of a better word, 'ghosts' leave behind? Ectoplasm maybe? In hindsight I'm quite glad we didn't get any of that stuff on the bathroom floor. It could have been a bugger to clean it up.
Also, funnily enough she declined the offer to stand there posing while my wife ran to get the camera. She quite bashfully decided to vanish instead of electing to appear in one of the national newspapers. I don't know why. Maybe she hadn't had her hair done that day or maybe she couldn't stand the idea of being a celebrity. I can't say I blame her actually.
Anyway, seriously, photos can be faked and, as I am sure that your are aware, there are a number of 'ghost' photos that have been taken down the years that have not conclusively been proved to have been faked but they don't provide evidence to the sceptics do they? Before we get into the usual, we need scientific evidence before we believe in these things, then I'd just like to point out that I was simply sharing the fact that these things have happened to my friends, family as well as myself. I don't even pretend to know what it means and I'm not making this up as I have a lot better things to do with my time. People can choose not to believe me (and all the other countless anecdotal evidence of hauntings) if they want but they are missing out on accepting what is undoutedly an important part of the human condition. How important a part of the human condition it actually is would be anyone's guess. People do see and experience 'ghosts'. Fact!