Photographing architecture on commission is a slightly chaotic mixture of accident and control. I think about the process in terms of rigour and fluidity. Many aspects are completely out of your control. For example, natural light, how it falls and moves, the weather. And the lives of people occupying a place. I made several unsuccessful visits to adjacent rooftops before making this image of Brookfield Place in Calgary on behalf of the UK's Arney Fender Katsalidis.