He disdains the post-processing done by many photographers that turns the night sky into a brilliant cerulean, with stars rendered as colorless dots. The key to accurate color, he says, is to use the right black reference point when editing image color in post-processing. All the photos in this story are natural color, with the exception of the Milky Way image below. He processed it to demonstrate a subtle way of adding the popular blue but false color to an image—the correct way to produce incorrect color, so to speak, while keeping natural color in the brighter parts of the Milky Way.
Read all about the Photoshop work required on his website, where you can also download Mc-color-stretch a free, open source program to help extract more color and detail in astrophotographs. In images that combine a landscape with a night sky, another issue comes up: The night sky is moving relative to the earth but the landscape is not.
Clark uses a technique in which he takes tracking shots of the sky and stationary images of the landscape, then combines them in software. This method can also be used for purely celestial photos, such as that of the Comet Lovejoy—the comet was moving faster relative to the star field. Clark made tracking images of both, then combined them in separate layers in Photoshop. This allows shorter exposures for individual panels, and gives you a very high-resolution image.
Clark uses PTGui Pro software for this. Finally, another technique is to take multiple sequential images of an event, such as the lunar eclipse, and combine the images in post. Photographing the atmospheric phenomenon of aurora borealis is a challenge for photographers. This difficulty is due to frequent spectacular changes in the brightness of the light. The charged solar particles move very fast and sometimes get hidden making it impossible to shoot them.
However, if you follow these tips, you will be able to get the best aurora borealis photos. Anchor your camera on a strong tripod to keep it steady for longer exposures. Set the ISO at the range of to Shutter speed can be as long as 30 seconds depending on the amount of light available. Do not rely on the built-in light meter, which is better left for day time use. Although any kind of lens will do for aurora borealis photography, you should choose a wide-angle and faster lens.
As the light begins to fall, look at the cloudy skies. Watch the colors and how they merge through the clouds. Even though it is dark, you should try using an 80A blue cooling filter to enhance the blue cast of the sky and to reduce the yellow cast from the artificial lights.
But Sady admits that this lightweight set up has its disadvantages. There are many places within driving reach where light pollution is low and the stars are bright. This is a lesson I learned the hard way when I went out several years ago to photograph a lava waterfall at dawn as it dripped into the ocean. The scene was amazing but the wind was howling and, despite my best efforts, very few of those images were sharp enough to use.
The main source of light in the night sky is the moon. Earth is out on one of the spiral arms of our galaxy. When you can compose so that you are looking back into the core of the Milky Way, that is when you will see the best stars.
What makes for an interesting photograph goes hand in hand with your surroundings. Look for locations that have dark skies and a landmark in the foreground that draws the viewer in. It goes without saying that getting away from light pollution is a must. Keeping an eye on weather patterns, local wildfires, and air quality are all worth checking before you go. Any cloud cover will prevent access to photographing the night sky. A metropolitan city with an abundance of lights will drown out the brilliance of the night sky.
This layer shows light levels measured by NASA. If the area immediately around you has high levels of light pollution, explore the map to find the closest location with a low amount of light pollution.
Another resource is to check if there are any Dark Sky Parks and Sanctuaries around you. These are designated areas of land often found in remote locations, far from any source of light pollution. Living in Nevada, Sady has easy access to several of these designated areas. It is one of the darkest places in the contiguous United States. Consider including interesting features of the landscape in the foreground of your image to help tell a story and convey a sense of place.
Familiarize yourself with the night sky using apps and other resources. PhotoPills is a fantastic photography app to use for planning. Light pollution is an important consideration when selecting a shoot location. Get as far away from city lights as possible, and if possible, go to higher elevations where there are less particles in the air to scatter light.
This will make your images clearer and more detailed. These four items are enough to get you started:. You can only expose your image for a short time before the stars are no longer pinpoints and begin to trail in your image. A mm wide-angle zoom lens ideal to use on a full-frame camera, or a mm lens on a crop-sensor camera. Just remember that the Rule is a rule of thumb and should serve only as a starting point.
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