St. Patrick’s Day Northern Lights
Went searching for the Aurora Borealis aka Northern Lights in central Minnesota. Fittingly this event occurred on St. Patrick’s Day on March 17, 2015. A bit of the green glow in the sky and even a green horseshoe…well sort of.
The kp index is an indicator of the strength of a geomagnetic storm and it was hovering in the 8-9 range all day and into the hours after sun down. That’s a strong storm and in central Minnesota you need at least a 4 to pick up the aurora. I think 7 or more is ideal but even later in the evening when it dropped to 5 or 6 I was able to get some good shots courtesy of the camera.
You can read more about this storm at Space.com.
When photographing the Northern Lights I approached it similar to shooting the Milky Way. Using long exposures at high iso. That way you can collect the faint parts of the aurora and since you’re likely in a dark area you can even get some foreground. If the aurora is really bright in your area it may be hard to get both the sky and ground exposed without light painting or bracketing exposures.
These were all shot wide open with either a 2.8 or 4.5 aperture. Ideally a 2.8 or faster would be best. ISO was shot between 1600 & 6400m. Most of the one’s I used were ISO 3200 or 6400 so it’s important to have good low light performance from your camera and good noise reduction software. Exposures were between 10 seconds and 30 seconds. The 10 to 15 second exposures were good for catching pillars of light dancing while longer exposures caught more color with less definition. You’ll need to adjust for the intensity of the display and your ambient light conditions if you venture out to catch them.
Here’s a site I like to get the latest aurora forecast from. It also has a concise primer on what you need to see the aurora and links to other sources. That’s one of many resources out there. Good luck!