Jak fotografować zorzę polarną

It sounds so easy, photographing aurora. You see some colors in the sky, point your camera and click, you got a picture. Unfortunately that is not how it works. In this article you'll find out how you can come home with amazing pictures of the aurora that will last a lifetime.

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It all starts with good equipment, no matter on which latitude you are. If you think that you can make pictures with your mobile phone or compact camera, then we have to disappoint you. That will not work. You won't see the aurora on your pictures. The sensors in these cameras are just not sensitive enough. You'll need at least a system camera or a Digital Single-Lens Reflex camera (DSLR) that has a full manual (M) mode and can be placed on a tripod. The tripod will be needed because auroras need a relatively long exposure time. Do not take pictures without a tripod, the pictures will come out blurred because of the movement of your hands. Shutter times can vary strongly from just 1 or 2 seconds for bright auroras but also 30 seconds for weak aurora that are nearly impossible to see with the naked eye. More on this a bit further in the article. When it comes to lenses, a light sensitive wide angle lens is needed. An ideal lens for aurora photography would be for example a 11mm f2.8 lens. An optional accessory that you can consider is a remote control. With a remote control you can take pictures without touching the camera. This prevents vibrations that you will otherwise see on your pictures. If you don’t have a remote control, No problem! Also with the self-timer you can make excellent pictures without having to touch the camera.

Obraz: A DSLR with a light sensitive wide angle lens, mounted on a tripod with a wired remote control.

Exposure times

The exposure time for a satisfying exposure can vary widely. Sometimes 3 seconds is enough to capture all the shapes and structures that form the aurora but it could also take up to 30 seconds depending on the brightness and activity level of the aurorae. Try to make multiple pictures with different exposure times to see which photos gave the best result. The average exposure time for a good picture of the aurora is about 20 seconds when using an ISO value of 400 during high auroral activity with a fast lens. When using ISO values higher than 1600, the pictures will contain more noise and that degrades image quality, so try to avoid using high ISO settings when possible. A low ISO setting of 200 or 400 often give the best result with minimal noise in your pictures but you might need longer than desired exposure times with these settings. Play around with the settings and see what works best in your situation. Every situation is unique!

Wartość apertury	64 ISO	100 ISO	200 ISO	400 ISO
1.4	35 Sek.	25 Sek.	12 Sek.	6 Sek.
1.8	60 Sek.	40 Sek.	20 Sek.	10 Sek.
2	60 Sek.	45 Sek.	25 Sek.	12 Sek.
2.8	2 min.	90 Sek.	45 Sek.	25 sec
4	4 min.	2 min.	90 Sek.	45 Sek.

Ogólne wskazówki i wytyczne dla wysokich szerokości geograficznych

What is it all about when it comes to photographing the aurora? We have the gear now but what else do we need to think about before we can start making pictures? It is pretty easy to divide it into 3 categories: the weather, your location and geomagnetic activity. Enemy number one is the weather. Is there bad weather and clouded? Bad luck. You won't be able to see aurora trough the clouds. Don't give up that fast and always keep an eye on the sky because if the clouds start to break up, then there might be a chance to see a glimpse of the aurora. So don’t hang out in that sauna all night! Another important aspect is of course your location: unless you're on Antarctica, this rule applies: the more north you are, the better. For Europe a general rule is that as soon as you're above the arctic circle you will have a good chance to see some auroras even if the Earth's magnetic field is in a quiet state. There will always be moments that the aurora will show up at such high latitudes. Another thing to consider is that you'll need to find a place that is as dark as possible (away from city lights) with a clear view towards the northern horizon. This is especially important when the Earth's magnetic field is quiet. When the space weather is quiet, the aurora can be so weak that it actually resembles a cloud for the untrained eye. If you're not 100 percent sure what you're looking at in the sky, Take your camera and make a picture. Does the "cloud" look a bit greenish on the picture, then you are looking at very weak aurora. If there's a coronal hole active or if you're witnessing the arrival of a coronal mass ejection; in that case you're lucky! When the space weather conditions are right (see our other articles) then intense and active aurora will be visible in a great part of the sky. These auroras can even be right above you or also on the southern part of the night sky!

So, this sounds promising already! Of course you want to capture all of this with your own camera, so we will provide you with the some useful tips and tricks. The settings you're going to use is something you will have to experiment with yourself. There is no golden rule or settings that are always going to work. What you'll always have to do is putting the camera on a tripod with the remote control (if you have one). Turn off autofocus on your lens and put your camera in manual (M) mode. Set your aperture to the lowest possible value and for zoom lenses make sure that it is set to the widest possible field of view. If your camera and/or lens comes with image stabilization then it is wise to turn this off. When it comes to finding the perfect focus for your lens then try focusing on the stars or another object in the distance. If you're not 100 percent sure what the optimal sharpness of your lens is? Practice this by taking a picture of the stars or the horizon. Look back on the computer if the pictures came out nice and sharp. No computer around? Go on your camera to the picture viewer and zoom in on your picture to see if it is in focus or not. When it comes to the aurora, it can come in many shapes, colours and intensity. During quiet geomagnetic conditions it can be very static and weak. You might have to raise the ISO values and/or increase your exposure time. Decide for yourself what you think is an acceptable ISO setting for your camera. You can use shorter shutter times with a higher ISO value but this will also add more noise to your pictures. How this noise looks like and the amount of noise you'll get is different for every camera. Play a bit with this and decide for yourself which ISO setting you find acceptable.

When the aurora is very bright and energetic, a shutter speed of only one or two seconds could already result in a satisfying picture. However, when the aurora is weak, it might happen that you will need an exposure of 20 or even 30 seconds to get a decent result. Do note that auroras move! You might lose some detail during long exposure times because of this. These movements are usually rather slow but you'll notice that during long exposure times a degradation of the details in the aurora. During moderate geomagnetic activity the degradation of the details can already occur after more than 5 seconds of exposure time.

Going on an aurora chase in the winter season? Then there are some additional things to keep in mind. Because of the cold, your battery will last a bit shorter than you are used to. Consider buying a second battery, especially if you're planning to stay outside for a long time. Keep this second battery close to your body to keep it warm. Are you putting your tripod on a surface with deep snow? Make sure that the legs don’t sink in the snow. It would be a shame if you'd notice that your tripod gently sinks in the snow and you'll end up with a skewed photo.

So what are the best times during the night to photograph the aurora. It all depends on the geomagnetic activity but most of the time the best times to photograph aurora during the night is from 10 'o clock in the evening to 1 'o clock in the night but it can also show up much earlier or later then these times. During a geomagnetic storm it might even be possible to see auroras from sunset to sunrise. No date planned yet? Consider going around the equinox. For unknown reasons, aurorae are more common around these two times (21st September and 21st March).

The last and perhaps best tip we have for you is: have patience. Auroras come and go. If there is nothing to see then don’t fear. They might just suddenly appear 5 minutes later. Don’t be disappointed when there is nothing to see, there will always be a moment that it will appear. Stay alert!

Photographing auroral details and structures on the high latitudes

Real amateur photographers want to go a bit further when it comes to photographing the aurora. Of course you want to give attention to the shapes and structures of the aurora but when you combine this with a nice foreground it will give an extra dimension to your pictures. Here are some tips!

To have the best chance at capturing all the fine details and structures of the aurora, it is wise to photograph from about half eleven in the evening to midnight. This time frame will be your best bet at photographing some nice auroras because the auroral oval reaches it's maximal extent. Keep in mind to give attention to the foreground in your frame. Try to frame in some interesting objects or landscape to enhance your photo and avoid capturing street lights as they could overexposure your picture and wash out the aurora. To not disturb your night vision use a red lamp. Before you go outside it is wise to have your camera cooled down a bit already so the lens doesn’t fog up which will result in bad pictures.

When you see the bright arches that form the aurora, you open the shutter of your camera by using your remote control and lock it in case you shoot in BULB mode. Set your camera to the lowest possible f-value (aperture value) to keep the exposure time as short as possible. If the aurora moves much then it is important to not expose your picture too long because this will cause loss of detail and even blur the aurora. As you can see: photographing the aurora is a real challenge but it can result in pictures that everyone will enjoy!

General tips and guidelines for the middle and low latitudes

For the middle, and especially the low latitudes, it's a lot more difficult to capture auroras. First of all, the parameters of the solar wind and interplanetary magnetic field (IMF) need to be so favourable that the auroral oval shifts enough southwards. The lower middle latitudes need a global Kp value of 7 for auroras to appear on the northern horizon. During severe storming (Kp8 and Kp9) it will be visible higher on the northern night sky and it could show up even right above you. This of course depends on your location and the intensity, but it is a very rare occurrence. The low latitudes need at least Kp8, but Kp9 is preferred. Is there a geomagnetic storm developing? Then keep an eye on the magnetometers. For European viewers we use the the Kiruna magnetometer (Sweden, Europe) to know when the chances are the highest. A good tip for the Kiruna Magnetometer is that as soon as the X-component shows a deflection of 1300nT, visual aurora will be possible for the lower middle latitudes in Europe. For photographic aurora it's already possible when Kiruna shows a deflection of 700nT. Photographic auroras are so faint that they are impossible to see with the naked eye. This kind of aurora will be coloured red. A camera is many times more sensitive than the eye and will pick up this light much sooner than our eyes. When all of these conditions are met it is important to be on a location that is as dark as possible, with clear skies. Especially towards the north, because that is where the aurora will show up. Make sure that there are no cities or villages towards the northern horizon. Light pollution can look a bit similar to the aurora that we are trying to capture so be very sure that the northern horizon is clear of light pollution. The last thing you want is to come home with pictures that only show light pollution. This glow will show up very bright on your pictures because of the long exposure times. If there is any aurora, light pollution will overpower them so be very careful when picking your location!

Aurora visible from The Netherlands on 15 March 2012. Kiruna showed a deflection of 1250nT and that was enough for Ide Geert Koffeman to capture it.

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