Tommy Thompson painted "Emerald Lake" in British Columbia, while attending the "En Plein Air Masters Chateau des Arts Mentoring Seminar" in Lake Louise, near Calgary, Alberta, Canada. This one-week seminar took the six artists in Kevin Macpherson's session to several locations in the Canadian Rockies to paint onsite in the open air. The artists had to work quickly to get their images on the canvas before the light changed.