Significant chance of auroras tonight through mid-latitudes

Spaceweather.tv aurora projection

The wonderful Dr Tamitha Skov of Spaceweather.tv is reporting that we have good chances of visible auroras in the mid latitudes from tonight and through the next couple of nights.

For Australia, this means as far north as Sydney.

Click on this picture to click through to Dr Skow's full video report:

Of course you will want to try to capture such a rare event on camera. You'll need to get away from city light pollution, somewhere high with an unobstructed view to the south.

Set your camera on a fixed tripod. Put the camera in Live View mode and zoom right in on a bright object. At the moment, Venus, Jupiter and the crescent moon are all very bright in the early evening to the north-west. Set your camera focus to manual and get these targets as sharp as you possibly can. Then zoom right back out, being very careful not to touch the camera focus ring.



With a zoom length of 18 to 25mm, you should be able to take a shot of 20 to 25 seconds length without the stars 'egging'—starting to extend from round into lines due to the Earth's rotation. To do this, set your camera to Full Manual mode, then set the shutter speed to 25 seconds to start with.

Set your shutter release to a two-second release so it can settle any vibration from pressing the shutter release before the shutter actually opens. Better still, use a cable release or an intervalometer (remote release) if you have one. Better again, if you know how, is to set your camera to start the shot with the mirror locked up. This means even less vibration. Shooting with Live View activated actually mimics this by starting with the mirror lifted out of the shot.

Then you need to run several test shots until you get the exposure right. Start with the ISO about 800 and the aperture in the mid range and do a test. Keep adjusting these two setting until you have clear bright stars but without the sky itself being blown out—grey or even white. Zoom in on the shots as far as you can go to make sure the stars aren't egging. If so, back off the exposure to 20 seconds.

Once you can get a reasonable starfield photo, then you are ready to capture any auroras that do show up. I hope you rugged up against the cold! I find ski gear is ideal.

While you are waiting, why not download the ISS Detector app (Android) or ISS Spotter (iOS) and see of there are any passes of the International Space Station or Iridium flares in your area that night. This is a whole different challenge for the night-sky photographer—to capture moving objects in space. With the 20 to 25 second photos as explained above, and an approximate idea where these events will occur from the above apps, you just need to point your camera that way, and do the same thing as you would for the aurora. The ISS will draw nice lines across the sky due to the high speed of its passage. The Iridium satellite telephone satellites are very reflective and cause very bright but very short flares that will amaze you, and thrill you if you manage to catch one on camera!