1. A method of generating light transport coefficients relating a digital projector to a digital camera, said digital projector having an array of projection pixels and said digital camera having an array of sensor pixel, said method comprising: simultaneously activating a first group of projection pixels within said projector to project a first test pattern on a projection scene, any projection pixels not in said first test pattern being maintained dark; capturing a first image of said first test pattern on said projection scene; simultaneously activating a second group of projection pixels within said projector to project a second test pattern on said projection scene, any remaining projection pixels not in said second test pattern being maintained dark, wherein said first and second groups of projection pixels have only one projection pixel in common defining a target projection pixel; capturing a second image of said second test pattern on said projection scene; comparing image pixels of said first image to corresponding image pixels of said second image and retaining the darker of two compared image pixels, the retained image pixels constituting a composite image; identifying all none-dark image pixels in said composite image, said none-dark image pixels defining non-zero light transport coefficients associated with said target projection pixel.