Living in the Portland metropolitan area I don’t get many chances to photograph star trails. There is too much light pollution from the city lights not to mention the very few clear nights so when I am traveling to remote areas where there aren’t any city lights to brighten the sky and the forecast calls for clear skies, oh yeah, and the moon is just a sliver, I find a nice dark place to set up my camera to photograph star trails…
There are actually several ways to photograph star trails. I’ll share the method I have been using lately. I set up my tripod in a dark area, put my camera on manual BULB setting, aperture at f5.6 with ISO 200, long exposure noise reduction turned on in camera and insert a fully charged battery. I select a wide angle lens (14-24mm or 24-70mm range), put it in manual focus and set focus at infinity (note:use a flashlight and actually set the focus to the infinity mark, don’t turn the lens to the end, it goes beyond infinity and you will not get a sharp image) find the north star which is just off the end of the two stars that are farthest from the Big Dipper handle and aim my camera to the skies, plug in a remote release (I use a Nikon MC-36) close the rear cover on the viewfinder (if you have one) and click…
The above image was made using a ninety minute exposure. With in camera noise reduction turned on, the total length of time your camera is on is double that of your night exposure. So, once the ninety minutes was up, my camera blinked “JOB NR” while it made another ninety minute exposure of black giving itself a reference for reducing the noise. If you aim directly at the North Star, you will get a circular effect as the stars travel around the North Star like in the above photo.
To add interest to your star trails, put something in the foreground. While in Moab recently, my porch looked out at the cliffs along the Colorado River so, I used them to give me a base for my star trails and I aimed off center of the North Star giving more of an arc than a circle…
I light painted the cliffs in the foreground to bring out the color rather than having a silhouette. And then there are those happy accidents where I set my camera for a second round and even though I couldn’t see it, the light of morning began to bleed into the image adding a warmth to the sky…
Using this method, post processing is very easy. I simply added a pass of NIK Dfine 2.0 to further reduce the noise, added a contrast curve and the results are what you see above. The longer the exposure the longer the trails will be. I’m going to have my AC adapter with me in Alaska next week and if the skies are clear, I plan on shooting a 3-4 hour star trail to get longer trails. This will definitely require the AC adapter as my camera with a fully charged battery is good for about the ninety minutes of exposure and the ninety minutes of NR. So, the next time you find yourself beyond the reach of city lights at night and you have a clear sky, give star trails a shot!
Tech Facts: Nikon D3S, with AF-S 24-70mm mounted on a Gitzo GT3541LS tripod with Really Right Stuff BH-55 ballhead, MC-36 remote release (to lock the shutter open for the long exposure) and a flashlight to see what you are doing while setting up. Camera on Manual> BULB setting (ninety minute exposures), aperture 5.6 with ISO set to 200. In camera long exposure noise reduction turned on. Lens set to manual focus with focus set to infinity. Click, set your alarm and go to bed!
***Two quick notes…I set my white balance on Auto and try to find a place off the beaten track. In the Grand Canyon, we found a pullout off the road and took our cameras down the path a bit to avoid any headlights that may come our way. Just at the end of a 1 1/2 hour exposure, Ranger Ricck pulled into the turnout to see if wee were ok. His headlights bathed our cameras in light. I dashed to the cameras releasing the shutters as quickly as possible but, they all had a warm, bright glow about them…1 1/2 hours of work shot down in mere seconds….
Oh yeah, if you go somewhere in your car and plan t sit it out, take your computer, ipad or some other device to watch movies. It sure helps to pass the time. 
Thanks, Steve for brining the entertainment to while away the long cold hours of night.
