Star Trails | Ursa Major and Minor

I was inspired by a recent post in the blog Cosmic Focus by fellow amateur astronomy Ggreybeard in Australia. He put his DSLR camera on a tripod facing north and attached an intervalometer. The result was a series of 100 images each 45 sec long stitched together showing the star trails across the northern sky. I encourage you to go visit his blog to see the beautiful image.

I noticed Ursa Major and Minor, the Big and Little Dippers to most people, in the northwest sky in recent summer evenings when I was out with my telescope or binoculars. That post by Ggreybeard made me want to try the same thing. I decided to try to get the star trails using two different camera setups.

NightCap Camera

My iPad has the app NightCap Camera on it. It can capture many varied low-light scenes including one called Light Trails. I set the iPad on a stable base and started the exposure. It lasted for 1 h 7 m 46 s. Some scattered clouds glided in that were lit up by ground lighting. Airplanes flew over in various directions with blinking lights. The resulting image showed it all. I added some yellow lines highlighting Ursa Major and Ursa Minor as well as Polaris the North Star. It was a messy yet interesting image.

25 Aug 2022 | NightCap | Light Trails mode | ISO 3072 | 4066.23 sec | 0.5 sec per exposure

Camera + Intervalometer

While the iPad was busy, I set up my digital camera with intervalometer on a tripod pointed at the same part of the sky. Manual settings included ISO 3200, infinite focus, and 1 sec shutter speed. I knew from tests that the camera would turn off after 3 min and 5 sec of inactivity. I set the intervalometer to capture an image every 3 min and do it 20 times. The 20 images were layered using Pixelmator Pro and the layers set to Lighten. The clouds were present in the last few images and kind of spoiled the shot. But, I could see the trails were readily visible.

25 Aug 2022 | Canon SX60HS | ISO 3200 | 1 sec | 20X

The next night was without clouds. I set the digital camera again for 20 exposures. This time the results were what I hope for.

26 Aug 2022 | Canon SX60HS | ISO 3200 | 1 sec | 20X

18 thoughts on “Star Trails | Ursa Major and Minor

  1. Fascinating. I was volunteering in Shenandoah today. We were talking about next time we camp, we should hike to one of the overlooks and try to do some night sky photography. I have an app for that, but have never tried. I’m always too tired.

  2. Well done, Jim. Star trails are indeed fun to capture.

    I installed Night Cap years ago, because I saw its potential. Yet I have never used it, preferring my DSLR.

    After seeing your Night Cap image, your post has inspired me to experiment with it when an opportunity arises. Simplicity is sometimes the key.

    Thanks for the nod towards my own star trails post, much appreciated.


  3. I have some affection for these constellations. They were among the first my dad taught me to recognize, c. 1950 or so. It’s fun seeing them from this different perspective.

  4. Great post Jim. I use the built intervalometer on my Nikon to photograph star trails. It is also handy to capture meteors. A 14mm lens, with a 30 second exposure with 2 seconds between exposures is bound to capture a few falling stars. If not a star trails photo can be created with the photos in photoshop. If shot in RAW the stacked image is also RAW. Very nice. A few years ago you had to colour correct each image before stacking, terribly time consuming. I read the above comment. That eye test was even used to pick out sharp shooters in the First World War. I would have failed. Take care.

      • Hi Jim, I have a Nikon D700. It is a very good camera, 12 megapixels on a full frame sensor. However, it has to be 12 years old and we are due for an upgrade. I am thinking about getting a Nikon 850, 45 megapixels on a full frame sensor. Of course I will probably have to get a new computer to download the pictures because they will be HUGE!

  5. I really like these pictures — I have only seen star trail pictures that were lines before; I really like the individual dots. It is a fresh idea to me!

    • Thank you. I appreciate your feedback. My camera is the same as yours, I believe. (Canon SX60HS) The longest continuous exposure is 15 sec. To get around that, I needed a lot of individual shots layered. It took an hour.

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