The standard technique in the digital age to take star trail photos is to take a series of still photos and then combine them into one single image like this one:
I used StarStaX to combine the images. It is a free program for the Mac that is very easy to use and gives great results.
If you have been reading this blog you know I have been spending a fair amount of time looking at the remarkable photography coming from the International Space Station (ISS) - the astronauts have been taking images of Earth and its cities from their vantage point in space.
The resulting movies, like the one linked in my last post, vividly show off their view from on high and that the glow of city lights can easily be seen from space. Since the individual frames for the movies are available, I decided to try some "star trail photography" using the images from the ISS. The result was this jaw-dropping image:
The shot was produced by adding some 900 frames taken as the astronauts passed from SW Texas to New Brunswick, Canada. It vividly shows that, even from space, the lights of our cities are dramatically brighter than the stars. The city lights form bright streaks across the view. They are the result of poorly directed light, a waste of energy almost too large to comprehend.
Next, I created a time-lapse movie from the images, stuck on the original movie and gave it a bit of narration. Here's the result:
The problem of light pollution is not unique to North America. This view of the European Union shows that continental Europe also has a lot of work to do in switching to more environmentally-friendly lighting.
It doesn't have to be this way. The International Dark-Sky Association is working to end light pollution, but your help is needed. By joining the IDA you can contribute to the cause and help the environment by cutting energy waste, greenhouse gas emissions and sky glow. This can all be done by using responsible lighting that still provides for safety and security while limiting light pollution.