Boing Boing reader Camera John shared this photograph in the Boing Boing Flickr Pool, and explains:
I started zoomed in and out of focus. During the exposure I zoomed out and focused it. The best way to get it in focus during the exposure requires a little prep work. First zoom all the way out or to your stopping point and focus on the tree/subject. This is where everything should be lined up at, at the end of the exposure. Next take a small piece of masking tape an put it on the focusing ring. Put another piece, aligned with the focusing ring tape, on the zoom/focal length ring. Now you can see where to stop. Zoom in, unfocus the camera and take your shot. You might be out of luck if you don’t have a dslr/slr.