The relationship between film and its audience is based on a convention of a passive audience who sit and receive the sound and image that make up the film. Film is a form of communication that, like language, relies on established codes and references - moving image, narrative, and conclusion. Lis Rhodes' films rely on the viewer's engagement. The film is not the only thing at work: the viewer's own interaction and translation is a key element.

Photographic representation is important in Lis Rhodes' films - she interrogates the construction of images, and how that construction is based on conventions. Orfiso for example uses a photograph of a road in France, A Cold Draft shifts between stills, and Pictures on Pink Paper repeatedly returns to an image of a countryside path leading to a five bar fence. The semiotician C S Pierce writes of photographs: '[they] are very instructive, because we know they are in certain respects exactly like the objects they represent. But this resemblance is due to the photographs having been produced under such circumstances that they were physically forced to correspond point by point to nature.' In the same way as the words 'here' or 'there' operate within language, a reference is required in photography for the visual referent to become meaningful. Like the fingerprint or bullet hole, the photograph is fundamentally linked to the physical presence of what it signifies or represents. We are all aware that the photograph may reflect the surrounding world - but that mirroring is a subjective marker, photography does not equal truth. Film is constructed from a series of still images, and Lis Rhodes utilises photographs as symbols of this failure of a single image to be objectively representative.

This engagement in the languages of film is extended in the expanded cinema work Light Music (1975, b/w, sound, 25m, 2 screen installation) where the image of the film is a musical score, drawn using pen and ink. Within film the use of an optical sound track is common - but this phrase 'optical soundtrack' is surely contradictory. How can one combine something optical with sound? A series of horizontal and vertical lines literally represent the sound here. What can be perceived visually is a representation of what can be heard, whereby the noise corresponds to the spaces between the lines appearing on the screen. This work is designed for the audience to move away from the position of a static viewer, to move in and out of the screening. This creates a set of social relations against the definition of traditional film - the film becomes a collective event where the audience are invited to make interventions into the work itself.

As Lis Rhodes states, conditions and intentions motivate her work. Conditions of film, of unequal power relationships and motivations of making the invisible visible. By injecting doubt into assumptions, she engages with film in cultural, critical political and social contexts.

Lisa Le Feuvre is a writer and curator. She is Associate Lecturer at Birbeck College and lecturer at Chelsea School of Art.