The dry desert air of southern Utah has some of the best stargazing in North America. And if you get up into higher elevations, or in winter, it’s even better. Why do the stars on colder winter nights often seem to have that extra pop? I know in the northern hemisphere winter shows a significantly dimmer Milky Way than during summer. So the stars, at least in the direction of the Milky Way, are certainly more numerous and brighter in summertime. So I’m not too sure why the colder it is, the brighter the stars appear. Perhaps it’s just perception.
On this night during my recent trip through the American desert Southwest, I wasn’t too sleepy. So I went outside with my binoculars and took a look at the Orion Nebula. That glance was enough to cause me to get my camera equipment set up for a timed exposure. Besides, this was one of the reasons I came here to Kolob Canyons, a separate and not well-traveled section of Zion N.P. Take a look at my previous post for daytime fun and photos here.
Kolob Canyons is the highest part of Zion, much higher than the main Zion Canyon. I was up at around 6000 feet (1830 meters) when I took this picture, but the sandstone mountains you see are well over 8000 feet (2440 meters). This is a winter night sky, so you can see in the lower right the constellation of Orion the Hunter. His belt is the three stars in a row, oriented almost vertically, and the Orion Nebula shows up brightly to the right of his belt.
Above Orion in top center you can see bright Jupiter. Just to the right of Jupiter is the star cluster called The Hyades, which is part of Taurus the Bull’s face. Above Jupiter and the Hyades you can see The Pleides, that famous star cluster also known as The Seven Sisters. I recommend looking up the Greek myth surrounding all of these constellations. It’s a great story.
The diagonal area of bright and dense stars is the winter Milky Way. In winter, the northern hemisphere is pointed away from the center of our galaxy. Since we are out in the “suburbs” of the galaxy, this view is much more dim than in summer, when we’re looking towards the galactic core. Nevertheless, a long exposure can bring out the winter Milky Way and make it look slightly brighter than it looks to the naked eye.
I took an exposure for the mountains and foreground, where my camera was dead still and tripod-bound. A half-moon (which is actually very bright) was illuminating parts of the landscape quite well, so I went with a low ISO (100) and an exposure time of a bit over 3 minutes. This resulted in an appropriate exposure for the foreground landscape. I say appropriate instead of correct exposure because if you expose as if this was a daytime photo, the foreground will come out looking much too bright for a starscape photo. I think it looks a little strange next to the darker sky.
The exposure time was plenty long enough to give the stars time to form short trails. But since I don’t really like this effect (I’d rather see the stars as they appear while stargazing), I exposed a second frame of the same scene with my tracking mount turned on. A tracking mount will turn your camera slowly to keep up with the Earth’s rotation, so the camera follows the stars. But if your exposure time is much longer than 30 seconds, the camera movement blurs the foreground landscape. The solution? Take the two images into Photoshop and merge them together so you have both the stars and the landscape sharp.
This was a long-winded way to say that this image is the result of two exposures of the same exact scene, merged together into one. There is on my blog a more detailed explanation of how I do starscapes, in this post. Stargazing and photographing the stars is a favorite of mine. Look for similar posts in future.