Over on the AuroraWatch UK Flickr page, photos of stunning auroral displays are shared with us regularly by some of the UK’s most talented photographers.

Although aurora seen from the UK is often considerably weaker and less frequent than more northern countries, it doesn’t mean that it’s not there. As many of our followers have discovered, using the power of photography to capture the aurora can yield amazing results.

This article provides a basic introduction to photographing the aurora, which camera settings you should be looking for, and how to give yourself the best chance possible at getting a great photo. For more information on how to determine if you captured the aurora, have a read of this other blog post.

Exposure Time

When your camera takes a photo, the shutter opens for a set period of time to let light hit a digital sensor or film. This period of time is known as the exposure time, and most SLR cameras will have options to change it. If an aurora is quite dim and hard to see by eye, increasing the exposure time will allow more light from the aurora to enter the camera and so the aurora will appear brighter when you then look at the photo.

Because your camera is going to be taking in light for a much longer time than usual, a tripod to keep it stationary is also essential to so you don’t get any effects due to motion blur.

There are tradeoffs to increasing exposure however; take a look at my very first aurora photo:

Increasing the exposure time doesn’t just let in more of the light from the aurora; it lets in more of other light too. Notice in my photo, all of the lights in the town and the light reflected off the moon are enhanced. I got away with it in this photo because the light pollution wasn’t too strong and so the aurora wasn’t drowned out. If I’d have been somewhere where the lights were stronger, I might not have seen the aurora at all.

Another side effect of using long exposures is “light trails” caused by moving lights, with car headlights being the biggest offenders. As light from the same object is appearing in multiple different positions at the same time (as far as the camera is concerned), it can blur or show things which aren’t really there. This picture by AuroraWatch UK team member Steve Marple shows this quite beautifully:

As far as smartphone cameras are concerned, most do not support true long exposures where the shutter can be kept open (though many of the latest “flagship” devices do). However, there are apps available which can simulate this by taking and analysing many short exposure shots to create a combined image. You can find these on your respective smartphones app store.

ISO

The ISO setting on a camera lets you change how sensitive it is to incoming light. By increasing this level, you allow the camera to take in more light per second, meaning you can then go on the use a shorter exposure time. Finding the balance between ISO and exposure time is a delicate task and very device dependent.

Using long exposures work well if what you’re photographing is staying still, but the aurora is a dynamic and has fine structures to it, so you could end up with blurry or smeared images. Increasing ISO to compensate for this means you can still capture some fantastic structure.

The base ISO level of a typical camera will usually range somewhere between 100 and 200. Increasing to 400 means that the camera is twice as sensitive as 200; 800 is four times as sensitive, and so on. Be careful when using very high iso settings though. As your camera is essentially amplifying the signal it’s getting, the image can become distorted just like sound when you turn speaker volume all the way up.

Hardware

You will find that nearly any camera, digital or film, is capable of capturing the aurora so long as you can adjust the exposure time. You don’t have to have the most advanced lenses or flashy camera, but if you are in the market to upgrade your kit, the following tips are for you.

In terms of lenses, you want be looking for one with a wider angle, or ‘field of view’. This is achieved by decreasing the lens’ focal length (the distance from the sensor to the lens itself) and allows you to get a shot that is wider and includes more aurora. Aurora hunters tend to not want to restrict their view with long lenses which only see a little bit of the sky, so wide angles lenses are the default ones of choice.

Camera sensors are built in to most cameras and are not easily changed, so it’s important to consider the sensor size before buying a new camera. A larger sensor will collect more light in the image resulting in much better photos, especially at low light (such as when capturing the aurora!). The “megapixel” count isn’t quite as important when you have a larger sensor. If you know what kind of photography you want to be doing and what lenses you will use, the sensor size should ideally be in a 1:1 ratio with the lens. If the sensor is too small, light that is coming through the lens will be wasted as the sensor can only pick up a portion of it. Make sure you take this into account so you can unlock the full potential of any lenses you use.

Last but not least, never use a filter when trying to photograph the aurora. Filters stop certain wavelengths (types) of light from entering the lens, which is exactly what you don’t want to do. Unwanted effects like aberration can also happen when using a filter.

Extra Tips and Starter Settings

• If you are looking directly at the sky when shooting, focus your camera to it’s maximum setting (often known as focusing to infinity). If you have scenery in your shot that you would like there (trees, houses, etc), then focus to that.
• Using a shutter timer or a remote shutter switch will remove any shaking of the camera resulting from you pressing the manual shoot button – which could add unwanted blur to your image.
• Make sure your battery is fully charged and, if possible, take a spare (and keep it somewhere warm). If you’re spending a lot of time in the (usually cold!) British outdoors, your battery will drain faster than usual.
• If the night is particularly cold, you may need to be think about how to prevent condensation/frost forming on your lens. A lens hood or dew heater will help.
• If your camera is able, shoot using the RAW file format (rather than JPEG for example). RAW files allow you complete control of how the photo looks if and when you come to process it (e.g. through Adobe Lightroom).
• Turn your flash off. A flash will not make the aurora any brighter and will just end up lighting the foreground, making the background appear darker – the exact opposite of what you want!

Feel free to use these exposure and ISO settings as a base, then adjust accordingly depending on your situation and needs as you get more comfortable using them.

Slow aurora: 15s Exposure, 400-800 ISO

Fast aurora: 7-10s Exposure, 1200+ ISO

We hope to see a new influx of aurora photographers joining our already large community over on our Flickr page. There you can see the stunning contributions from our UK wide followers, as well as all the camera settings they used to help you on your way.

If you have any tips you’d like to share, please use the comments box below, or join us on Facebook and Twitter.