Your complete guide to the aurora australis
What is it?
The northern and southern lights are reminders of our link with our volatile Sun.
Aurorae observed in both hemispheres have the same origins. They occur when solar flares — huge bursts of particles and mag-netism — are thrown out into space by the Sun’s coronal mass ejections (CMEs) and penetrate the protective magnetic field around the Earth. This solar wind collides with particles in Earth’s upper atmosphere releasing photons. It’s these bursts of light that we see during auroral displays. Solar flare activity rises to dramatic peaks at the height of the Sun’s 11-year cycle.
How to find it
These factors are key to observing the southern lights, says Fred Watson.
Location: Head as far south as you can.Tasmania provides the best opportunities, but Victoria, southern NSW, and the most southerly parts of SA and WA are occasionally treated to aurorae.
A clear horizon: So that your view isn’t obscured by trees or buildings, pick somewhere with a clear horizon, such as a south-facing coastline.
Avoid light pollution: The relatively low-intensity aurorae seen from our latitudes are easily drowned out by city lights. Choose a site far from artificial light sources and with no artificial sky-glow to the south.
Freedom from moonlight: Moonlight can also dilute an auroral display, so choose a time when the Moon’s phase is between the third quarter and new. Aurorae can be seen at any time during the night, but the best displays are often seen between 8pm and 2am. Long winter nights provide the best opportunities.
Technology: Websites such as spaceweathercom or aurora-service.net provide forecasts of auroral activity, and several Facebook pages offer aurora alerts. It’s worth practising with night-time landscape photography to perfect the technique of recording low light-levels. Auroral colours can be subdued to the eye, but show up well in digital photographs.
How to shoot it
Photographer Luke Tscharke shares his tips for capturing images of aurorae.
Camera: Set your camera to manual mode so you can adjust the shutter speed and aperture. Use a tripod to support your camera and a camera remote to release the shutter.
Lens: Choose a wide-angle lens to fit in more of the scene.
Aperture: Select the widest possible aperture (lowest f-stop value) to allow as much light as possible to enter the camera. This is generally f/2.8 to f/4, depending on the lens.
ISO: Choose the highest ISO value for your camera that produces images with acceptable noise. Try ISO 800-3200 to start.
Exposure time: Auroras constantly move so choose a shutter speed of 5-15 seconds to capture their detail. Shutter speeds greater than 15 seconds turn the aurora into a red-green glow.
Focus: Set the camera/lens to manual focus. Adjust the focus to infinity by selecting ‘co on the focus scale of the lens, or you can focus on the Moon or a bright object far in the distance. Use trial and error to obtain sharp focus.
