The Manual Input Sessions is a series of audiovisual vignettes which probe the expressive possibilities of hand gestures and finger movements. The concert is performed on a combination of custom interactive software, analog overhead projectors and digital computer video projectors. The analog and digital projectors are aligned such that their projections overlap, resulting in an unusual quality of hybridized, dynamic light. During the performance, a computer vision system analyses the silhouettes of the performers’ hands as they move across the glass tops of the overhead projectors. The hand gestures are then analysed by our custom software. In response, the software generates synthetic graphics and sounds that are tightly coupled to the forms and movements of the performers’ actions. The synthetic responses are co-projected over the organic, analog shadows, resulting in an almost magical form of augmented-reality shadow play.