Study in Light and Dark (2004)
black card, light projection, variable size
A more abstract demonstration of the equivalence of incident light and reflection. A double square of matt black card has one half of it very brightly illuminated (the light level adjusted so that the brightly lit part looks the same as the less illuminated white wall.) The illusion becomes clear if the viewer interrupts the light beam (see second image)
Normally painting is concerned with variations in a reflective surface (ignoring variations in incident light), and projections (film or video) are concerned with manipulating variations of incident light (ignoring, by minimising, variations in reflectivity of the projection screen).
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