You mentioned something about a roof nearby; I recently got on the to of my place of work's roof and tried to take some shots of the Full Moon.
I rested the camera ( for a 1sec exp) on a ledge and the roof angles down from that ledge.
When I took the shots - no matter what FL or focusing- I got two ghost images.
I put it down to the reflection of the roof (tiles).
Maybe it was a piece of glass (or something like that ) that acted as a prism and reflected from the roof from a car or something like that.
My $0.02
Bartman
