Have you ever wondered how star trails would look in a photo at different camera exposure times?  I thought it would be helpful and interesting to see the lengths of star trails over different periods of time as they “move” across the sky, so I created this gallery. The star trails exposure time examples below are 9 different lengths: 10 minutes, 20 minutes, 30 minutes, 40 minutes, 60 minutes, 90 minutes, 120 minutes, 180 minutes, and 235 minutes.

In order to create these images, I pointed my camera at the north star in my backyard and set it to continuously shoot 30-second time exposures over and over. After it had recorded 235 images (roughly 4 hours), I used the startrails.exe software from www.startrails.de to render the final images.  Each of the images below has the same starting time, with a longer exposure time than the one before it. See the captions below each image for the exposure time.

If you are interested in photographing star trails yourself, check out our article, How to Photograph Star Trails for a complete tutorial on how to reproduce this effect yourself. I’d love to hear your feedback and see how your photos came out!