Star Trails

While spending some time in the mountains over Christmas, I took advantage of the opportunity to shoot some star trails.  I worked on this two different nights and used two different techniques.  The first night, I did one 60 minute exposure.  The challenge with this process is that you end up dealing with a lot of camera noise and it can be tricky to get the exposure correct.  My settings for this image were:  3633 Sec - f/8 - ISO 200 - 16mm.  Overall, the results weren't too bad.  I added some fill light and contrast adjustments in Lightroom 3 as well as some noise reduction.  The combination of the long exposure and the bit of ambient light allowed for some detail in the snowshoes and skis in the foreground.  I'm not sure where the light is coming from that is causing the bright area in the background.

For the second image, I did things a little differently.  Instead of one long exposure, I took multiple shorter exposures and then combined them in post-processing.  It was much easier to get the exposure correct and because of the relatively short exposures, camera noise was not an issue.  With this image, I left the Christmas lights (solar-powered) on; they would have been completely blown out in the long-exposure image.  My settings for the images were: 30 Sec - f/2.8 - ISO 400 - 16mm.  I set my camera on continuous shooting and manual focus.  I used my cable release and locked the shutter open.  I let it run for more than an hour and ended up with 104 images.  I had originally planned on around 200 images, but I got started late and had to quit because the nearly-full moon was coming up.  You can see the effects of the moonlight on the foreground snow, skis, and snowshoes.  I think it really adds some depth to the image.  The images were converted to jpegs in Lightroom and then combined in a free software program that I downloaded from www.startrails.de.  This simple but effective program only took a few minutes to process the images.  I saved the result as a tiff file and then did some final tweaks in CS5.  Overall, this is a much stronger image.  The foreground detail and the clean, noise-free sky and star trails work really well together to create an image with impact.