Also, in an attempt to capture as much bounced light as possible, a large white foam core card was placed in front of the camera with a hole large enough for the camera lens to fit through. Finally, a 1 inch square was cut on the top face in order to allow light to pass through. The top of the box was fitted with a glued layer of tin foil which ensured that the intense lightbulb would not shine through the white foam core. Duct tape would have also been sufficient. The edges of the box were taped together using specialized tape which was fairly opaque in order to not allow any light to leak in. Red, green and white, or red, blue and white materials were used for each face of the box. ![]() Colored construction paper simply wasn’t adequate as it was far too absorbent and much too textured. In addition, the texture on it was minimal and it was sturdy enough to avoid creasing/bending/scratching. These materials were a soft rubbery foam which seemed to be the most ideal because they were neither too absorbent nor too reflective. This measurement was chosen because it was the maximum size the colored materials came in. The box faces were constructed out of flat white foam core, each 9 inches squared. ![]() Since my model does not meet these exact specifications, my results have only come close and will never duplicate the real Cornell Box’s lighting conditions with total precision. The Cornell Box has very specific width, height, depth, surface, lighting, and various other properties and specifications which must be adhered to as closely as possible in order to achieve precise lighting simulations. This means that most of the box was constructed based upon the theory of the Cornell Box rather than the specifications. Having said that, the construction of my Cornell Box was loosely based on the Cornell University Program of Computer Graphics’ Cornell Box specifications. For this reason, it is worthwhile to reference their model as the definitive Cornell Box. Not only do they supply object measurements, lighting and camera information, but also surface reflectance properties and much more. It is first important to mention that while there are many versions of the Cornell Box throughout the internet, the Cornell University Program of Computer Graphics’ version probably has the most detailed one available. This fascinating site contains all relevant information pertaining to the Cornell Box ranging from it’s history, comparative studies and data specifications. Perhaps the most comprehensive archive regarding the Cornell Box can be found online at the Cornell University Program of Computer Graphics. This paper focuses on the construction of a physical Cornell Box model and all lighting tests associated with it. The Cornell Box is a simple physical environment in which lighting, geometry, and material reflectance properties are measured and then compared to a computer generated model in order to test simulated lighting accuracy.
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