Tree and star trail

A perfectly clear night means the perfect time to try out a star trail shot.

My intervalometer seems to have chosen tonight to stop working. So, I stuck the camera in burst mode and used an elastic band and a penny to jam the shutter release button down. Frustratingly, it seems to have given up after 100 shots complaining that the buffer is full. I wonder if it only finishes writing everything after the shutter release is released?

Time for some googling.