Generally the Aurora Borealis, or Northern Lights won’t appear, or be at their best until late in the evening. This means setting up your gear and shooting in pitch darkness !.
It pays to have everything to hand and familiarise yourself with your camera settings making sure you have spare batteries for the camera, warm clothes and a small torch or head torch.
Due to the long exposures a sturdy, full height tripod is essential to keep the camera steady. A cable or remote release will also be handy to trip the shutter keeping your hands free from the camera and preventing movement.
Prime lenses with a maximum aperture of F2.8 – F4 are ideal, also a depth of field scale on the lens barrel is handy for hyperfocal focusing techniques. It is also worth trying out shots with a zoom lens especially when you have a variety of subjects to shoot.
Wide apertures are the best choice, anywhere from F2.8 to F5.6 should give a reasonable exposure time and still give enough depth of field to keep the lower half of the frame sharp.
Depending on your camera model an ISO setting of between 400 and 1600 is ideal. The higher ISO’s will be fine be the latest Canon 5DMK2’s and Nikon D3’s but older cameras will suffer from hideous noise at these settings so a lower ISO 400 or 800 will give better results.
Exposure times will vary from 8 seconds to 30 seconds maximum, anything longer than this and noise becomes a problem, you will also notice that stars will start to trail.
The Aurora will move constantly so longer exposures can sometimes blur this movement where a shorter 8 second exposure will capture the swirls and patterns.
1: Pick your foreground subject and set the camera on the tripod making sure everything is clamped down.
2: Switch to manual focus, focus on infinity then pull the focus back slightly. Alternatively if your lens has a DOF scale you can focus using the hyperfocal method, (the focus point/distance will depend on the lens and focal length).
3: Select the BULB mode. This is usually at the end of the exposure times in manual mode, (just after 30 seconds). When you press the shutter button it will hold the shutter open until you let go of the button, (most cable releases have locks on them).
4: Wait for the shot then trigger the shutter, keep a check on exposure time on the camera timer or a watch.
5: Check your histogram, if it’s banked right up against the left hand side just increase exposure time and/or open the lens up a stop.
A few common mistakes !!.
1: Using a torch during exposure will bounce light around either through the viewfinder or across the lens spoiling exposure.
2: Camera movement during exposure, tripping over the tripod for instance !!
3: Trying to track the ‘Lights’ as they bounce around the sky – just pick your spot and be patient.
4: Bad focussing due to either leaving the autofocus on in camera or on the lens and the lens will hunt or forgetting to re-focus when you move. If you have a subject such as a building in the foreground you can use a torch light to aid the camera in pre-focussing.
TOP TIP – Just stand back when you can and enjoy the lights, it’s a great experience.