Weekly Photography Tips - Star Trails

Star trails are unique night sky images that show the movement of the stars, which is of course actually the rotation of the earth. They were one of the first types of nightscape images I shot.

The star trail image can be produced in two ways, super long exposures or by combining dozens to thousands of single images. They can be shot in any direction but are especially interesting when shot towards the north or south.

My preferred method is to stack individual images rather then leaving the shutter open for anywhere from 20 minutes to an hour. All it takes is one miss aimed headlamp or flashlight to ruin 30 minutes worth of work. By shooting shorter, single images you have the ability to simply pull the mistake out and keep going. I also like the polar shots because of their captivating circular pattern.

I begin by finding a fairly dark spot with interesting foreground. The still water of a lake can have the unique effect of reflecting part of your star trails. I setup my camera to capture night sky image but instead of just shooting a few I use an intervalometer to capture image after image for a period of time. The rule of thumb I have always used is at least 20 minutes but the longer the better.

The really great thing about shooting trails is that you can set it up and then move on to capture other images if you have a second camera, take a nap in your car or climb into your tent and go to sleep.