SHOOTING WITH THE STARS—NIGHTSCAPE PHOTOGRAPHY
By Allen Utzig
As the sunset’s purple and pink hues fade from the sky, outdoor photographers pack up their gear and head for home. Most don’t realize that in two hours, the sky will turn into an awe inspiring photo opportunity. Countless stars offer the prospect of breathtaking photographs and the Milky Way, when seen in a dark sky, can produce a jaw-dropping, if not mystical photographic experience. Nightscape photography is simply creating night time landscape photographs that include a star filled sky and exclude, to the extent possible, any artificial light. We are not talking about photographing deep space here. This is about night time shots that can be captured using equipment found in almost every camera bag.
Begin your nightscape photography by finding a dark sky; not an easy task in these days where much of the earth is lit up by artificial light. To identify areas free or little affected by light pollution, visit the Blue Marble Navigator website. This site uses Google maps and NASA’s night lights imagery to visually display light pollution virtually anywhere in the world. This is an incredible resource and it is free so take full advantage of it.
Once you’ve found a “dark sky” location, you need to know when the moon will be lighting it up. The moon can be a positive or a negative. A crescent moon can nicely illuminate the foreground while the light from a larger moon will outshine many stars and may result in a disappointing photo with fewer stars than you actually saw. For best results, look for times before moonrise or after moonset or when the moon phase is the first or last quarter. You can find moonrise, moonset and moon phase for any day at the U.S. Naval Observatory Astronomical Applications Department. Choose the date and location, and the site supplies the information. You will also want to know where in the sky to find the Milky Way. A simple way to locate it is by using another free software program called Stellarium. It is a planetarium for your computer that displays the night sky for any place at any time of any day of any year. A quick glance will show you where in the sky to look for the Milky Way.
Making nightscape photographs is much simpler than most think. You don’t need any special equipment. A camera, a wide angle lens, a tripod and a shutter release cable or wireless shutter release and a flashlight are all the gear you need.
Nightscape photography demands high ISO settings, wide open apertures and slow shutter speeds, so you must use a camera that allows full manual control.
Shooting a star filled sky calls for a wide angle lens; one of 28mm or shorter is essential. Here’s why: A lens longer than 28mm may not allow the camera to capture enough light to produce a quality photo without also creating star trails as the increased length magnifies the impact of the earth’s rotation. Furthermore, a wide angle lens maximizes the number of stars in your photo.
Remove any filters from your lens, including protective skylight or similar filters. These filters increase the chance of lens flare and some also reduce the amount of light entering the camera.
You MUST use a sturdy tripod. There is simply no practical way to create a sharp, nighttime photo without one.
Shutter Release Cable
If you put your hand on your tripod mounted camera to press the shutter release, you are sure to introduce vibrations. With a shutter release cable, you can make the exposure without touching your camera.
A bright flashlight or headlamp will help you find your way to and from your photo location. A headlamp will free up your hands and one with red LEDs will provide sufficient light to make camera adjustments while preserving your night vision.
Preparation and Set-Up
Before making nightscape photos, prepare your camera by turning off anything that is set to automatic. No aperture or shutter priority and no auto focus or auto ISO. You cannot let your camera choose the settings for you. It is as dumb as a rock and it doesn’t care if you are photographing a sunrise or a night sky. You must make the decisions and to do that, set your camera to manual mode.
Set your image quality to RAW. By shooting in RAW, there are no compression algorithms like those used in jpeg files that throw data away. With a RAW conversion program like Adobe Camera Raw, you can make all kinds of non-destructive revisions such as removing color casts generated by the ambient light without losing any data. If you are unable to shoot in RAW, capture your image using large jpeg files.
The white balance setting should be simple. Stars produce the same kind of light as the sun. The fact that the sky is dark doesn’t change the color of the light, only its intensity so setting white balance to “daylight” makes sense. My experience has shown that the daylight setting produces a color that is too warm so I usually select the setting for “incandescent light” or set the white balance to 3200K.
Shooting in RAW allows you, in your RAW conversion, to adjust the white balance to the setting that looks best.
Because you’ve turned off auto-focus, how can you be assured that your shot will be in focus? A wide angle lens, even set to its largest aperture should keep everything sharp if you set your focus to infinity (∞). A full frame 35mm camera with a 28mm lens set to f4 and focused at infinity should render everything outside 22 feet in acceptable focus. A 17mm wide angle lens should keep everything in focus beyond 10 feet. While setting the focus to infinity should work in most cases, you must know the infinity setting location on your lens. Ultrasonic motors on zoom lenses need room to move so the infinity setting doesn’t have a sharp infinity demarcation. It may have a mark on it showing where infinity will be in focus so line up your focus ring with that mark. Some lenses, especially those with manual focus, will lock the focus on infinity when you rotate the focus ring to the infinity (∞) setting (right image) so focusing on infinity is simple. Unfortunately, some lenses don’t have distance scales or infinity markings.
If your lens doesn’t help you find infinity focus, the best way to assure correct focus is to arrive at your site before it is dark and use your auto focus. After you have achieved the proper focus, turn off the auto focus and be careful not to touch the lens again until you have completed your session.
Infinity indicator on auto focus lens.
Infinity mark on manual focus lens.
Composing your photo in the dark is also problematic. How can you compose a shot when you can’t see anything through your viewfinder? You should be familiar with your location and plan your composition in advance. That said, even if you have a pre-planned composition, the way to capture it is to point your camera in the direction of the photo you want to shoot. Then make a test shot using a high ISO setting and a shutter speed of two to three minutes. Don’t worry about the quality of the photo; you are simply trying to create a good composition. When the exposure is completed, view the photo on your camera’s digital display. Make compositional adjustments and take another test shot. Continue to make test shots until you have the composition you want. When the composition is right, change your settings for the proper exposure.
A good composition and these settings will enable you capture a quality nightscape photo.
Adjust your ISO value to the highest setting you can without introducing excessive noise. Newer cameras can produce relatively low noise photos at ISO settings of 6400 or higher. If you are limited to ISO settings below 6400, use the highest setting available.
Set your aperture to the widest available for your lens. Depending on how high an ISO setting your camera will allow, setting your aperture one stop slower may significantly improve your shot. Wide apertures tax a lens’ ability to deliver sharp images. Using f-4 rather than f-2.8 can render a better photograph.
To get the shutter speed right, remember the “Rule of 600”. It holds that the focal length of the lens multiplied by the shutter speed should not exceed 600 if you want to produce sharp stars. The “Rule of 600” works but a product of 600 is a maximum and 500 is even better.
To capture enough light on a moonless night, you will need a shutter speed of at least 15 seconds so a short focal length lens is essential. Using a 24mm lens will allow a shutter speed of 25 seconds (24 * 25 = 600). A shorter lens will allow for an even longer open shutter. If you follow the Rule of 600, the stars in your photos should look like dots in the sky in normal viewing or when printed at normal size. In fact, the tiny star trails will actually make the stars look slightly larger than they appeared in the night sky.
There is some question about whether the “Rule of 600” applies equally to full frame and “crop” cameras. The answer is that they are virtually the same. A “crop” camera is simply that, a crop. It doesn’t change the magnification in any way. If, however, you want to enlarge the photo beyond the camera’s native size, the tiny star trails will be magnified and are more likely to be noticed when being viewed, so “crop” camera users should keep that in mind. The larger pixels in the sensor of a full frame camera make a slight difference but not significant enough to matter.
After you have made the final settings and are ready to make your photo, ignore the light meter in your camera. Darkness will confuse it and it won’t give you an accurate reading.
When you’ve adjusted your camera’s settings, mounted it securely on your tripod and composed your shot, make some test photos. Check them to make sure your composition hasn’t changed but more importantly, recheck your focus. Nothing can be more disappointing than photographing the night sky, only to find out later that everything is out of focus.
Once you start creating nightscape photographs, it is important that you make lots of exposures of each composition. You may be surprised to find that the night sky isn’t just filled with stars. It includes a lot of “junk”. Orbiting satellites, space debris and airplanes are so common that nighttime photos frequently end up with unwanted streaks in the sky. Often they are not visible to the naked eye, but with long exposures your camera will capture them. The streaks can be removed in your post processing, but it is always better not to have them in the first place, so make lots of exposures.
Space junk or not, creating great nightscapes that include the Milky Way or a star filled sky is as exhilarating as it is easy. So, don’t put away your gear when the sun goes down. Find a place to enjoy and photograph the magnificence of a dark sky.