Translucent optical view

A development of traditional optical views is the translucent optical view, which made it possible to create a visual effect of transforming the image by adjusting the incidence of light on that view. The peep show box, in addition to being a means of information about the world, was also a spectacle, competing in the eighteenth century with other visual shows, such as the magic lantern. To surprise the audience with visual tricks, as lanternists did, makers of peep show boxes made small perforations in the engraving, exactly in the spot where there was, for example, a window, a lamp or the Moon, and on the back they glued pieces of coloured paper. Sometimes, if there were large windows in the engraving, a hole the size of the window was made and a small coloured engraving was glued from behind. Then, illuminating this optical view from the front and then the rear produced the visual effect of transforming the same daytime image into night. Thanks to this technique, it is possible to "animate" the optical views representing the transition from day to night and vice versa.