The camera obscura (Figure 4) or dark room is a dark box with a hole that allows light in, casting an image through lenses and mirrors onto the opposite interior wall. This optical tool was documented in the early sixteenth century by Leonardo da Vinci with the purpose of aiding drawing to sketch a subject with precision (Janson & Janson, 1997, p. 453; Getlein, 2008, pp. 210–211). 

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