McCall's first solid light film, Line Describing a Cone (1973), consists of a 16mm projector and a role of film. McCall treated the role of film with a simple animation technique in such a way that a singel white dot on the screen gradually grows into a full circle. When projected in an open gallery space filled with a thin mist in the air the light beam of the projector becomes sculptural. With his solid light films McCall set out to examine the foundations of film offering a critique of the commercial cinema industry, its manipulation of time and space, its use of narrative, montage and suture and its problematic relationship to the viewer. McCall turns cinema's raison d'être on its head and draws the viewer's attention away from the projected image towards the projection beam itself. By presenting his work in a museum setting, McCall also challenges the visitor to relate physically to the moving light sculptures. The artistic context of the 1960s and early 1970s—the blossoming film co-op culture, expanded cinema, performance art, minimal art, structural film and conceptual art—provides the rich, multidisciplinary background against which to read McCall's projections.