The centuries-long era of painting on wooden panels culminated in magnificent works such as Grünewald’s Isenheim Altarpiece and van der Weyden’s Beaune Altarpiece. But then canvas finally came into its own: light in weight, low in cost, easy to prepare, and an ideal replacement for frescoes where climatic conditions did not easily permit mural painting, over time it became the artist’s medium of choice. This program traces the evolution of painting on portable media, giving equal attention to great wooden polyptychs of 30 to 40 panels and tiny canvases such as Vermeer’s The Lacemaker. (27 minutes)