Orion and Sirius over Sulphur Mountain and the Banff Springs Hotel in Banff, Feb 3, 2012. This is a 20-second exposure at f/2.8 and ISO 500 with Canon 5D MkII and Canon L-series 24mm lens. The gibbous Moon was just out of the frame at top.

Astronomy author and photographer Alan Dyer presents amazing sky sights