To put a name to a new kind of art, call it “thinking images.” For the imagery is in some sense alive. Having endowed it with its own structures and its own intentions, we set it free to figure things out on its own over the duration of the dance.

The essential characteristic of our imagery is this: It thinks by picturing things. It sketches the relationships it perceives as soon as it starts making them out. This keeps its frames in constant flux, for it continually re-adjusts itself as it tentatively advances its ideas. From time to time, we have it cast one kind of picture aside completely and bring another one to bear, trying out a new way of thinking.

What is the imagery trying so hard to grasp? The same thing we are: the intricacy of Trisha Brown’s choreography that all of us are watching as it unfolds.

To do so, the imagery focuses not on individual dancers, but rather on the patterns they form together. One such pattern, most easily perceived, is the spatial composition the dancers make at any given moment on stage — the spaces between them; the similarities and differences between their shapes.

But the deeper beauty of the dance lies in patterns unfolding over time, and so our imagery also has ways of remembering past moments and tracing correspondences to the present. Many of the pictures it makes are pictures of time. Like us, it forms expectations about what might happen next, and it registers its surprise if the dancing veers off unexpectedly.

Our hope is that the imagery illuminates the dance for you in a completely new way. This feels to us like birth.

What makes all this possible technically is the combination of three elements. A motion-capture system deploys eighteen infra-red cameras to capture the movements of the four dancers wearing reflective markers. These cameras and markers are what enable the imagery to see the dancers on the stage in the instant.

This alone would allow little more than the accurate recording and perhaps the rudimentary depiction of the dancers’ bodies. However, here these cameras are the eyes for a complex system of analysis and graphic action, an artificial intelligence of sorts. It is here that the images’ intentionality, memory and tentative grasp of the choreography are enacted.

Finally, these perspectives on the dance as it unfolds are projected using a real-time graphics renderer. Each diagram of understanding is generated live in 1/20th of a second and immediately updated in the next instant.

The combination of these three elements in a live performance is unprecedented.

how long… was part of the motione project of the Arts, Media and Engineering Program (AME) through the Herberger College of Fine Arts and the Fulton School of Engineering at Arizona State University. It was co-presented by ASU Public Events with additional commissioning support from Lincoln Center for the Performing Arts. It was supported in part by the National Endowment for the Arts, the National Science Foundation, Motion Analysis Corporation, Arizona Public Service (APS) and City of Tempe Cultural Services.

Choreography: Trisha Brown; Interactive Imagery: Paul Kaiser, Shelley Eshkar, Marc Downie; Composition and Sound Design: Curtis Bahn; Set and Lighting Design: Robert Wierzel; Costume Design: Galina Mihaleva; Motion Capture and Analysis and Interactive Systems: Gang Qian, Todd Ingalls, Daniel Whiteley, Jodi James, Thanassis Rikakis, Loren Olson, Marc Downie, Curtis Bahn, Siew Wong; Dancers: Neal Beasley, Sandra Grinberg, Brandi Norton, Cori Olinghouse, Stacy Spence, Todd Stone, Katrina Thompson; Project Directors: Thanassis Rikakis, Colleen Jennings-Roggensack; Choreographic Assistant: Carolyn Lucas; Assistant for Lighting Design: Greg Emetaz; Technical Directors: Kelly K. Phillips, David Lorig; Project Managers: Sheilah Britton, Michael Reed; Assistant Project Manager: Kate Collins.