The stars of the southern sky arc over the peaks of the Lake Louise Range in this half-hour’s worth of exposures.

For this shot I took 35 frames from a 200-frame time-lapse movie and stacked them to create star trails moving over about 25 minutes time when the sky was dark and moonless. I also layered in the moonlit landscape from a frame taken at the very end of the time-lapse sequence when the Moon has risen and was lighting the mountains and trees. So this scene is a bit of a Photoshop fake, but only so far as to merge exposures taken a couple of hours apart from the same fixed camera to combine the sky and stars from when the Moon was not in the sky with the ground from when it was, so the ground isn’t too dark and featureless.

What most people find surprising about star trail shots is the range of colours displayed. Some of the magenta trails come from a little chromatic aberration in the lens. But nevertheless, stars do exhibit lots of colours, but usually only in time exposures like this. As a bonus one frame captures either a meteor or an Iridium satellite flare at right above Mount Victoria.

I took the images for this scene on Friday, September 7, on a shoot at Herbert Lake in Banff.

– Alan, September 14, 2012 / © 2012 Alan Dyer