Mens du sov (While you were sleeping) is a book project by two Danish photographers documenting the graffiti underworld that happens after dark in Copenhagen. Presented as part of the I/O digital arts programme at Trailerpark Festival the installation invites the audience to pick up a spray can and spray digital graffiti onto the walls, revealing images from the book.
The setup consists of a computer, projector, infrared camera, and a spray can that has been customized with 3D printed parts, an infrared laser, and a tiny mirror. When the spray can's cap is pushed, instead of spraying paint, an invisible laser beam is reflected onto the wall. The laser is tracked by an infrared camera, and small parts of images from the book are thus digitally sprayed onto the wall in real time.
The installation is an example of how technology can be used as a communication tool for displaying images in a more tangible and engaging way by combining a physical object with a digital output.
Location: Copenhagen, Denmark