The night sky is breathtaking. If you go to a reasonably dark place and let your eyes adjust, you can watch and see thousands of light bites, each one being a star or galaxy several million years old. I find that completely humiliating.
The night sky is also an excellent subject for photography. With long shutter speeds, your camera can capture more light than your eyes, giving you a better view. Here is how to take a good picture of a starry sky.
What makes a good photograph of the night sky
The best photos of the night skies show thousands of small stars. They make you feel as if you were looking at an infinite universe.
They are also founded. An image that is just stars looks, at best, at one of NASA 's scientific photos or at a computer generated rendering.
Instead, superb photos of the night sky normally present a landscape as context. The immensity of the stars contrasts with something much closer to home.
The technical stuff
While you can take a picture of the night sky just about anywhere, you have to go into a dark place to get the best results. A city 30 miles away throws enough light pollution to affect your images. Professional astrophotographers tend to go far into the desert or into the mountains to get their photos. The best way to find a dark sky is to maps the light pollution of Dark Site Finder . You can see in the screenshot below that most of the eastern half of the United States is bad enough for near photography, but the West and Midwest has plenty of options.
If you can not get a really dark place, the best thing to do is to photograph the darkest horizon. I live in a fairly unpolluted area, but because it 's on the coast, I can take night shots, like the one below that shows the Northern Lights, as long as I point my camera at sea.
For night sky photography, you balance several things: you want to leave as much light in your camera without suffering the quality of the picture because of the stars that move or noise. This means that you want set your aperture to the widest possible value and your ISO to the highest value that gives you clean shots . For most cameras it will be about 1600. For professional cameras, you can go to 3200 or 6400 in one push, while older devices will probably have to fall to 800.
The shutter speed is a bit more complex for astrophotography, and it is related to the focal length you use. Because the stars move in the sky, if you leave the shutter open for too long, they will rub themselves, and instead of having sharp pointers of light, you will have strange blur as you can see on the picture below
Rule 500 is used as a guide to determine the maximum shutter speed you can use at a given focal length. Simply split 500 by the focal length of the lens, and you will get the answer in seconds. For example, if you take a picture with a 20 mm lens, the maximum shutter speed you can use without star streaks is 25 seconds.
Some warnings about the 500 rule. First of all, if you use a camera with crop sensor you should use the equivalent focal length for the calculation, it is ie multiply the focal length by 1.5 before dividing it into 500. The 500 rule does not work as well with very high resolution cameras. If you are using a camera with a high resolution sensor, you must divide the focal length to 300 to get a more realistic number.
A little simple algebra (or trial and error) clearly indicates that the shorter the focal length, the faster the shutter speed can be before seeing the star trails. At 17 mm you can get away with 30 seconds of exposure, then at 50 mm you will see them after 10 seconds. There is also another reason to lean towards wide-angle lenses : you get better pictures of landscape which means it's easier to [getmoreinterestingforegroundsinyourstarphotos
Since we are talking about the shutter speed measured in tens of seconds, it goes without saying that a stable tripod is an essential part of the kit. You will not be able to take pictures with your camera in your hands! Similarly, as the camera shake may be a problem, you should use a remote shutter or two-second countdown on your camera.
Autofocus does not really work at night so it is best to use manual focus. If your camera has a live display mode, use it to zoom in on the stars, and then manually focus your lens until it ' A pin.
Astrophotography is a time when shooting of the RAW is essential . You need more information in your pictures as possible.
The photography of stars, as you can see, is quite technical, but that does not mean that it is difficult. Just go out, follow the instructions above as close as possible and see what you get. Do not expect amazing results for the first time, but be prepared to learn from your mistakes.
Other tips and tricks
One of the great "secrets" of astrophotography is post-processing. By using Lightroom, Photoshop or your favorite image editor, go there and use the tools to increase details like details of shadow, highlight details, contrast and exposure . You also need to fine tune the colors by increasing the saturation and playing with the white balance. Tweak things up until they look good.
Here is the front of one of my photos.
And the after.
As you can see, a little post-processing really gathers it.
Here are some other tips to keep in mind:
The moon is really bright in the sky . If you are just trying to take pictures of the stars, try to go out on the nights without moon. Otherwise, it will simply interfere with your photos.
Even after sunset, its light still affects the night sky. Wait till the end of the astronomical twilight, that is to say when the sun has plunged far below the horizon so that its light rays do not reach the sun. atmosphere of your position. You can find the different dusk times on TimeAndDate.com .
It should be obvious, but the best time to take pictures of the night sky is a clear night. If there is a lot of cloud cover, you will not see anything.
If you want to take a picture of a specific constellation, use an app to help you find it. I like Sky Guide on iOS and Sky Map seems to be a great option Android .
Bring a headlamp with you when you go out to shoot stars. They are much easier to use than the flashlight on your phone.
I love taking pictures at night. This is really peaceful and since your subject is going nowhere in a hurry, you can take your time.