This is one of my favorite times of year in Alaska. The air is getting crisp and cool and the nights are getting darker. We have a very narrow window for comfortable star gazing in this state, and this last weekend provided an optimal blend of skies and weather. While many in Anchorage were out listening to Bill Maher, I was camped out on the back porch with my camera, honing my skills at astrophotography and watching the skies in the event that the aurora decided to come out and play.
For these particular images I used my 35mm f/1.8 “prime” lens. Most photographers prefer a wider angle, but this is the fastest lens I own because it’s relatively inexpensive and provides a wide enough angle for most of the events I shoot. To get the right balance of speed and field of view, I set the aperture or “f stop” to 2.8 to start with, then bumped it down to 2.5, the former seems to be the recommended setting for this type of work.
I also set my ISO down to 100. Most pros recommend letting the camera set the ISO, but I still haven’t quite mastered the automatic ISO on my Nikon. A lot of this was experimental. Shooting in town can open up your images to a lot of light pollution and I was hoping that the lower ISO would give a cleaner image.
For shutter speed I bounced back and forth, some I shot in aperture priority mode, really cranking the exposure control up to lengthen the shutter time. Others I shot on manual with a time of anywhere from 20 to 30 seconds. Most guides will tell you that 30 is a good starting point, but for this far north I found that the time was a bit too long and that I still ended up with “star trails”, where the positions of the stars relative to earth rotate in the time that the camera sensor is capturing the image.
The hardest part of shooting night images is getting things in focus. My Nikkor lens doesn’t have an “infinite” or afocal setting. Because of this, I have to spend some time trying to focus on things in the distance, taking test shots, and making adjustments to dial things in just right. After awhile you get the feel for where the sweet spot is in your range of focus. Oh and don’t forget to turn off your lens’ autofocus feature…
I processed these images in Lighroom 5, using some wonderful presets that I downloaded here. They really added an extra zing to the images, especially this one.
Overall it was a fun and peaceful night of experimenting with my camera. I didn’t stay out late enough to really catch the faint showing of aurora that Anchorage got Saturday night, but I did capture some cool light trails from passing planes and helicopters, with just a faint hint of something that looks like lady aurora dancing on the northern horizon. Hope you enjoy the images.