Magic Lantern

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Debated Origins

The beginnings of the magic lantern trace back to 1588, when Italian scholar, Giovanni Battista Porta, discovered a simple projection method. Porta’s projection involved sketching a design on the surface of a mirror, which was reflected by the sun onto a white wall or screen (Barnes, 8). A few decades later, Jesuit, Athanasius Kircher based in Rome, took Porta’s idea to an improved level in his book Ars Magna lucis et umbrae in 1646, where he describes several different projection methods with mirrors and lenses like Porta. Similarly, Kircher used a painted subject projected on a mirror, but instead of using the sun’s reflection, he used a magnifying lens, which enlarged the image on the screen. Kircher also figured out that creating reversed text to be reflected on the mirror would appear as it should on the screen or wall on which it was being projected. In addition to these discoveries, Kircher also illustrated a device that would show a series of images by reflection, utilizing an octagonal drum with several painted images rotated by handle (9). One of the devices that Kircher describes in Ars Magna, the lucerna capotrica, was confused for the magic lantern and lead to the crediting of Kircher as the inventor of the magic lantern. According to John Barnes’ History of the Magic Lantern, there is no evidence that Kircher explicitly knew whether or not his invention was a magic lantern. However according to various pieces of evidence before Kircher’s clear articulation of the magic lantern in the second edition of Ars Magna, the inventor of the magic lantern is either Dutch physicist Christiaan Huygens or Danish mathematician Thomas Ramussen Walgensten. Huygens appeared to have been working on a lantern for representations of paintings in a darkened room through various letters with his brother Ludwig in 1662, while Walgensten had been referenced as developing a magic lantern in several letters between Huygens and French scientist Pierre Petit in 1664. Walgensten however also is said to have demonstrated the magic lantern across Europe in Paris, Lyons, Rome, and Copanhagen. Whether or not Walgensten was the true inventor of the magic lantern, he is certainly responsible for spreading it (13).

Creating Projection: Lenses and Condensers

The magic lantern utilizes artificial light to project transparent slides and images onto a screen or wall. The projected image usually has a diameter that is thirty to eighty times larger than the transparent slide and an area one thousand to six thousand (Barnes 5). To achieve this magnification, the magic lantern contains a combination of several different concave and convex lenses. Most commonly used is the Petzval lens, which was used for photographer portraits. The petzval lens contains four lenses: -Double-convex lens and plano-concave lens in the front. One side of the double-convex lens is fitted and cemented to the plano-concave lens. -double-convex lens and concavo-convex lens in the back, moderately separate from the front combination of lenses. The combination of these lenses makes the projection better defined and flat on the screen or wall (Barnes 6). Though this lens combination is adequate for most lanterns, higher quality lanterns contain additional lenses with varying foci, which can be adjusted according to how the operator would like the projection to appear. In addition to these lenses, the magic lantern usually contains a compound condenser formed of two plano-convex lenses, which are mounted close together in a metal cell, with the flat sides of the lenses facing out. The condenser allows the magic lantern to have a short focus and enhances the quality of the projection.



Social Uses

A Centralized Music Library

Rise and Demise

References