Aurora in real time
Finally, a video of aurora that isn’t speeded up by today’s craze for time-lapse. For two nights in the early 80’s aurora swept far enough south to be overhead in central Maine (very rare; usually they’re on the northern horizon at best), and we were entranced by their visual Majavishnu dance. Slower than water in a stream and faster than clouds overhead, the rippling motion of aurora hit a real sweet spot for lifting viewers into an extended state of wonder. While of course video in a 500-pixel-wide portion of a screen can’t replicate this wonder, you can get a faint taste of it from this show in Canada’s Northwest Territories.
And check this out: the same footage with comparisons in real-time and time-lapse. As he explains, while real-time captures the actual feeling of the motion, that 30fps shutter speed dims the colors, while time-lapse sequences come closer to presenting the color as seen by the eye, at least for bright aurora.
Note, though, that many time-lapse videos of the night sky, using a series of still shots at wide aperture, clearly exaggerate the brightness, as compared to human vision; virtually all of the gorgeous milky way time-lapses do this to a fairly dramatic degree, as do some videos of fainter aurora. Real time video, by contrast, will, if anything, under-represent the brightness of the night sky.