Ghosts in the back yard

I took this picture of my back yard. Can you tell how this effect was done?

Interesting photo! Do they visit you often? Could YOU see them, or only the camera?

If it were photoshopped..it looks inverted or something then reduced opacity..I wouldn't have a clue how to do that on a camera...well, maybe having the shutter stay open and having the person move? no idea...how did you do it?? neat pic!

That is awesome! You have a ghost living in your backyard.