Star Trails

Star Trail Photography

In this blog my focus is on photographing star trails. Photographs with stars in the sky as pin points are interesting. Photographs with star trails where the movement of the stars is recorded around a fixed point are even more impressive and have been on my photography bucket list for quite some time. I needed to learn from someone who knew the night sky and how to photograph it.

Last weekend I had the opportunity to participate in a Night Photography workshop led by Kevin Adams. He is THE night photography guru in these parts. Kevin has a blog on Night Photography (http://www.kadamsphoto.com/nightphotography) and it has information that goes way beyond just photography.

 I traveled to Waynesville, NC, which is out in the vicinity of Pisgah Forest in western North Carolina.

For star trails, your camera needs to be on a tripod for steadiness and the camera needs to have a remote cord. The remote needs to have a timer with the capability of triggering the camera to fire the shutter for a set exposure time on a regular interval. We planned to set the exposure time for 1 minute at one minute-one second intervals. The camera runs until the battery dies or the media card has no more room-whichever comes first, so that we could leave the camera and get some sleep.

The idea is to position your camera so that it points toward Polaris or North Star. All the stars rotate around Polaris and when the movement is tracked by camera, it looks like a circular trail. We made sure the aperture was set to F/4.0, the shutter speed at 60 seconds, and the ISO set at 400, focal length of 19mm. (Camera Nikon D810 and lens 14-24mm.) We said good bye and prayed that our cameras would not be knocked over or carried off by bears.

Next morning we eagerly arrived back at the camera to find everything had worked perfectly except that about 2 hours after starting, dew began to form on the outside of the lens and all the rest of the photos were foggy with dew. At the end I will share some tips about how to avoid dew.

I had about 150 clear photos to use. All of these photos were stacked in a photo stacking software program such as Adobe Photoshop and here is the result.

20150803-StarTrails_KevinHouse

If the photo has abnormal light it’s because it was a full moon and once the moon was high enough in the sky, it began to look like day.

I love this technique that I learned and can’t wait to try it again.

Next week I will talk about Light Painting Waterfalls

Tips for Star Trail photography

  1. Get out of the city, away from light pollution, for the best results.
  2. Avoid shooting star trails during a full moon.
  3. Choose a clear night or you won’t actually be able to see any stars!
  4. You’ll need a camera that can take very long exposure photos. An SLR or digital SLR is perfect.
  5. Use a low ISO setting available on your camera to reduce the amount of noise in your final photo.
  6. A tripod is absolutely essential, the sturdier the better, particularly on a windy night.
  7. Wrap insulation around your lens to prevent it from fogging (particularly bad on very long exposures on cold nights). An ideal, cheap solution is to wrap socks around it and hold them in place with elastic bands.
  8. The Earth rotates around the north and south poles, so all star trails are centered above them. If you want to position this centre point exactly you’ll need to locate the North Star, or Polaris (northern hemisphere) or the South Star, Sigma Octantis (southern hemisphere).
  9. Use trial and error to figure out how long your exposure should be. Start with 1 minute or 60 seconds and double it as need be.
  10. Put something interesting in the foreground.
  11. To combine your images, I recommend a free program I have been using called StarStaX which is easy to use and it does a great job. Just point StarStaX to the folder that contains all the exposures, selected “lighten” as the blend mode, and let it go to work.

 

Some of these tips came from the following site:

http://digital-photography-school.com/how-to-photograph-star-trails/