Projection is both a technique and a conceptual framework. As a representational method, it refers to the use of lines or vectors, usually straight, to translate between two- and three-dimensional information. Conceptually, it refers to a way of thinking about 3D space and its representation, relying on empirical methods; non-arithmetic and precisely articulated information that is graphically manifest. Where does projection appear? Obvious applications are the fine arts, such as using perspective rendering for depicting spaces, or drawing plans and sections in architecture. Technology of the last century is quite dependent on projective principles, such as optics necessary to photography and cinema, virtual slicing of the body for medical imagery systems, and targeting weapons from handgun scopes to advanced GPS-based military hardware.
Projection at work: A 3D tree becomes a 2D image through the projection of its shadow. (Photo by the author)
Projection spans back to our earliest times, using shadows and celestial objects to assist humans in the depiction and manipulation of our environment. As such, the study of projection is the study of virtual reality. Since cave paintings and, later, celestial alignments of monolithic structures, and, later still, the early science of Ancient Greece, virtual reality–the ability to re-present real-world data graphically–has been a critical element of what made humans elevate beyond our ancestors. Developing spatial reasoning through imagining a top-view, like a map or a plan, required a disembodied eye aided by abstracted and alternate perception; seeing the world as only what can be seen by the eye was limiting. Early humans sought out what I call supravision, a neologism describing vision that sits above and outside normal, everyday vision. It is what philosophers and scientists have used to measure and describe our universe and it is what artists and architects used to plan and depict our world. It applies to disciplines and processes such as perspective, cartography, surveying, stereopsis, anamorphosis, orthography, astronomy, optics, light and shadow, weapons systems, origami, descriptive geometry, medical imagery, photography, cinema and more.
This blog will both find examples of current applications of projection systems, usually in short form, and expound on historical moments that projection was featured as a prominent element of a paradigm, movement, or process. The subtext to this whole endeavor is the current digitization of many, if not all, of our representational processes. Looking at historical references will build a context for understanding our current visual environment.
Assistant Professor, Lucian and Rita Caste Chair in Architecture, Carnegie Mellon University