I'm back from a quick 4-night visit to Yellowknife, Northwest Territories. It's one of the best places to go for aurora viewing, and this time of year is perfect since the cloud cover is generally low and aurora activity is often a bit higher around the equinox. Our first night was a complete bust, but the second and third nights gave very nice displays (considered just average for Yellowknife). And then on the 4th night we were hit with a very nice gust of solar wind, and the whole sky erupted in a fantastic show. The images below don't do justice, because there is so much rapid movement in the aurora that you really have to see it in person. Like a solar eclipse, the photo can never capture the full experience. I brought my 24 mm f/1.4 and the 14 f/2.8. I ended up using the 14 mm more, since the aurora displays are so huge. As expected, it was a bit chilly. On our last night, the dashboard thermometer registered -40 C as we were driving out to the viewing location. Fortunately there was no wind, so we survived. My new 1DX II and 5D IV both performed very well --- it amazes me that a camera can function at all in those conditions. The batteries died quickly in the cold, lasting about an hour. But I would just swap them out with a warm one, and once reheated they worked fine again. If anyone is keen to go up there, please get in touch and I can give you a host of tips and advice (this was my third visit to Yellowknife).