Charles M Falco is professor of optical sciences and of physics at the University of Arizona. Alongside his lifelong passion for motorcycles, his work has seen him collaborate with artist David Hockney on a research project into the historic use of optical aids in painting. Ultan Guilfoyle is an award-winning producer, director, and writer, whose films include Sketches of Frank Gehry (2006) and Making Space, Five Women Architects (2015).