When on assignment to capture Split Rock Lighthouse at night last week, I went down to the beach to take a star trails picture. I shot a few wide star trails and then got out a telephoto lens to zoom in on the lighthouse and took this picture. You can see just a touch of the northern lights over the lighthouse.
When shooting star trails, you leave your camera’s shutter open for an extended period of time. On the wide lens that I usually shoot star trails with, each picture takes 1 hour. As you increase your focal length and zoom in, you can capture star trails in a shorter amount of time. This shot is just about 6 minutes long and shows some nice streaking of the stars.