Long exposure and restless me

This evening I played around with my tripod and long exposure-times.
The only problem is my camera will show only a blank screen on the display during the exposure and after that for the same amount of time the word "Busy".
So I wasn't sure at what moment the camera was taking shots (and probably merging them in memory) and maybe the camera would use a timer before taking the picture, just to make sure the camera is not moving anymore. So I moved in front of my cam during a 15 sec exposure, just to make sure I knew when the exposure really was. :)
I now know the camera will take several shots and post-process them after. This postprocessing takes about the same time the exposure-time was set to.
It is also clear the exposure is a composite of several pictures, because my head is quite sharp, while you would expect some movement-smear.

The bright spot in the back is the moon :)