"Trombone" shot practice assignment:

Exposure mode: Shutter priority

ISO: 100

Handheld or tripod

Aim for a slow exposure, like 1/2 to 1 second. The camera will set the aperture automatically.

While the camera is taking the photo, zoom in or out. Try centering your main subject before you begin.

If the aperture blinks at you, it means the shot will end up over-exposed. Some over-exposure might be fine, but if it is too bright, you'll need to bring the shutter speed down. 

Try your own (we'll try in class tonight) and post to Flickr.