“What’s that, Daddy?” My first of two experiences of the Aurora Borealis was the shimmering backdrop to a childrens’ puppet show on black and white TV in the 1950s called ‘Meet the Penguins’. I never got a satisfactory answer from my Dad, and anyway, at that tender age, wouldn’t have swallowed a cock-and-bull story of solar particles interacting with the Earth’s magnetic field.
My second experience was to see them in the flesh when they were visible in Surrey in the 1980s. Noticing a weird patch of green in the sky in Leatherhead, I drove my son to a dark country lane near Polesden Lacey for a better view. The Aurora filled the whole of the northern half of the sky. We watched the slowly changing waves of red and green for about half an hour before they faded. Seeing the real thing filling my field of vision, it was hard to imagine how a photo could do justice to such an immersive experience. But I think I was wrong.
Simon began his talk with some of the myths and legends surrounding the Aurora and then with some of the science. They are caused by subatomic charged particles in the solar wind that are deflected by the earth’s magnetic field and drawn into the polar regions to react with the atmosphere. Curiously, some of the particles pass by the earth and are drawn back to be trapped in the field and help to form an ‘auroral oval’ around the polar regions.
The particles interact with elements such as oxygen to give a green glow and nitrogen at higher altitudes to give red. Other colours appear more rarely. Aurora coincide with the arrival of burst of solar activity generated when sunspots and coronal holes appear on the sun’s surface. It takes around 4 days for a burst to arrive, which by my reckoning means they travel at around a million miles an hour! However, predicting where and when they will be visible is difficult and no one can guarantee that your expensive and freezing cold trip won’t be fruitless. You can improve your chances of being in the right place at the right time using an App developed by the University of Lancashire which gives zones for the probability of seeing the Aurora at different latitudes, but these can change quite quickly with time.
Simon began photography with wildlife but capturing the Aurora soon became a bit of an obsession and he has taken many trips to Arctic latitudes to photograph them. He emphasised that all you can do is set yourself up at your chosen location and wait. They may or may not appear and, if they do, can last for a few minutes to several hours. The best times to go is at each end of the Arctic winter when there are still some hours of daylight giving extra opportunities for some daylight shots. This is from about mid-September to late November, and February to March. The first sign that they will appear is a kind of grey cloud that doesn’t look like a cloud and then, as your eyes accustom to the dark, the colours will start to appear.
His recommendations for equipment were: a good solid tripod and head, a camera that copes well with high ISO settings, a remote release, and a fast, wide-angle lens. Setting the focus can be tricky as autofocus won’t work. His favourite method was to focus manually on a distant bright star, then tape down the focus ring so that it can’t be moved accidentally. Check the focus periodically. Most camera lenses focus beyond infinity but using the focus scale and tweaking it back a bit is not reliable.
He also recommended using ISO compensation – perhaps someone can explain to me what that is!
Exposures can be a bit trial-and error, but as a starting point, try 15 sec at ISO 3500 with the aperture wide open. If you have a very fast lens, say f/1.8, you can try 2 sec at 800 ISO. If you want any stars to remain sharp, the ‘500 rule’ gives you a guide to the longest shutter speed you should use. That is, use a shutter speed equal to or shorter than 500 divided by the focal length of the lens.
He also highlighted the main things that can go wrong, apart that is from the Aurora failing to appear and your fingers ceasing to function from the cold. Unwanted light from other peoples torches, car lights and ambient light can ruin your shot. Make sure the camera is level. When bringing your camera into the warm, wrap it up to help stop condensation from shorting out the electronics. And if you do trip over a tripod in the dark, make sure it’s someone else’s!
We humans are hard-wired for hunting, a relic from the carnivorous habits of our ancient ancestors. In the modern world, to experience the thrill of the chase and capturing prey, many of us turn to displacement activities such as fishing, collecting antiques and taking photos. It’s a basic instinct we need to satisfy. Capturing the Aurora has it all – the planning, the surveillance, the patient wait for a sighting, the hopes for success, and finally the strike. It’s little wonder that Aurora tourism is becoming so popular.
Simon’s presentation was a tour de force on the subject and I could post another blog devoted to the many outstandingly beautiful pictures he used to illustrate it. Here are a few he kindly sent me to include. To see more, visit his website at www.wildearthpictures.com.