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Porta, a Neapolitan, blends fancy and showmanship for magic shadow entertainments in the 16th century—Barbaro and Benedetti put a lens in the “pin-hole” camera or camera obscura.

The first contact of the new dramatic art, then being developed in Europe and especially in England, with the magic shadow medium was made by a remarkable Neapolitan, Giovanni Battista della Porta.

Porta, a boy wonder, who would have felt at home in the modern Hollywood, put the room camera to theatrical uses. In a way Porta was both the last of the necromancers, who used lens and mirror devices to deceive, and the first legitimate screen writer and producer of light and shadow plays with true entertainment values.

Porta was born in Naples about the year 1538. He and his brother, Vincenzo, were educated by their uncle Adriano Spatafore, a learned man. The uncle had considerable wealth, which enabled young Porta to travel extensively and have the best available instructors. From boyhood Porta’s chief interests were the stage and magic.

At an early age he started writing for the theatre and his comedies are rated with the best produced in Italy in the 16th century. But even before he began his professional writing for the stage, he had developed an interest in magic and anything approaching the magical. This avocation was developed during the rest of his life.

Porta was very fond of secrets and secret societies, founding the Academy of Secrets at Naples. He was also a member of the Roman Academy of the Lynxes, scientific society founded in 1603—named for its trademark. Even magic inks for secret writing were an attraction to him.

For years it was generally believed that Porta invented the camera obscura but, as we have seen, it was known long before he was born. At the time of the discovery of photography Porta’s title to the invention of the camera was discussed and it was definitely established that while he made some refinements and, of course, devised some special uses, he had nothing to do with its invention.

When about 15, Porta began the investigations which led to the writing of Magia Naturalis, sive de Miraculis Rerum Naturalium, “Natural Magic, or the wonders of natural things.” The material was published five years later, at Naples, in four “books”, or large chapters. Through the years he increased his notes on the subject and in 1589 the work was printed in twenty chapters.

Porta’s Natural Magic was a popular book, a best-seller of the day. It was first translated into English and published in London in 1658. It was also translated into many other languages. Natural Magic contains a wide variety of subjects, including developments in the light and shadow art-science. Porta published the first detailed explanation of the construction and use of the camera obscura in the fourth “book”.

“A system by which you can see, in their own colors, in the darkness objects outdoors lighted by the sun,” was Porta’s title for the section. He continued:

If anyone wishes to see this effect, all the windows should be closed, and it would be helpful if the cracks were sealed so that no light may enter to ruin the show. Then in one window make a small opening in the form of a cone with the sun at the base and facing the room. Whiten the walls of the room or cover them with white linen or paper. In this way you will see all things outside lighted by the sun, as those walking in the streets, as if their feet were upwards, the right and left of the objects will be reversed and all things will seem interchanged. And the further the screen is from the opening, proportionately the larger the objects will appear; the closer the paper screen or tablet, is drawn to the hole, the smaller the objects will appear.

Porta also had an explanation of the persistence of vision, so far as it was then understood. As an example, he mentioned that after walking in the bright sun it is difficult to discern objects in the darkness, until our eyes become accustomed to the change—and then we can see clearly in the dim light. To see the natural colors, Porta proposed the use of a concave mirror as the screen for the camera images. He then discussed phenomena resulting from the principal focus of the mirror. He tried to use the parallel to show how we see things rightside up instead of upside down. But his knowledge was not sufficient for that purpose, for he held that the seat of vision was at the center of the eye, as the focus of a concave mirror or lens system. In this he was not correct, according to modern experiments, but at least it was a plausible theory.

As a third point in his description of uses of the natural camera Porta said, “Anyone not knowing how to draw can outline the form of any object through the means of a stylus.” Here was Alberti’s camera lucida, or the camera adopted for the use of painters and designers. Porta instructed his readers to learn the colors of the object and then when it was thrown on the screen it would be easy to trace and paint in natural colors. He pointed out another interesting and important fact—a candle or lamp could be used as the light source instead of the sun.

Porta concluded his account of 1558 with an assertion that the system could be used to deceive and to do tricks through the aid of other devices. His last words on the subject were confusing: “Those who have attempted these experiments have produced nothing but trifles, and I do not think it has been invented by anyone else up to now.” Earlier in his account he mentioned that he was now revealing what he thought should be kept a secret.

Roger Bacon, Alberti and Leonardo da Vinci and others were figuratively watching Porta when he wrote those lines and made those experiments. Even the same words about seeing people on the streets outside go back to Bacon, at least; and the use of the camera for drawing to Alberti and Leonardo. It is not clear whether or not Porta actually wished his readers to believe that he had invented the camera obscura which he described or that he had merely found some interesting applications. Perhaps he wanted the whole matter considered a secret.

But though Porta borrowed from the ancients without giving them credit, he deserves praise for publishing descriptions, following tests which he himself must have made. As in all sciences, the prehistory of the motion picture had experimenters and popularizes—and not infrequently the two functions were separated by a considerable period.

The developments claimed by Porta in the second edition of Natural Magic published in 1589 had been described previously by others. Once again he was a copier and popularizer rather than an inventor and discoverer. And that seems proper for a man who was by profession a playwright with a hobby interest in secret things, especially those relating to natural phenomena.

During the three decades prior to 1589, important developments were made in the science of optics. Both Barbaro and Benedetti described camera obscura systems fitted with lenses to improve the images, and E. Danti, an editor and translator, explained in 1573 how an upright, instead of an upside down, image could be shown through the use of a lens-mirror system.

Monsignor Daniello Barbaro published at Venice, in 1568, La Pratica della Perspettiva, “The Practice of Perspective”, a book on optics. He describes the instrument designed by Alberti, the camera lucida, and gives an illustration of it. As in the case of Benedetti, Barbaro’s chief title to memory is that he introduced the projection lens to the natural camera, thereby enlarging its scope. Without any lenses even a modern camera would give only inferior results and motion pictures would not be practical. It is also said Barbaro introduced the diaphragm, which is very important as a means of controlling the light in the camera.

Giovanni Battista Benedetti, a patrician of Venice, 1530–90, published at Turin a book called Diversarum Speculationum Mathematicarum et Physicarum Liber, “A Book of Various Mathematical and Physical Speculations”, in which was included the first complete and clear description of the camera obscura equipped with a lens. The date of the volume was 1585, four years before Porta published his revised edition.

Benedetti used a double convex lens. His first knowledge of optics came from a study of Archimedes, whom he admired greatly. But his learning was not confined to optics. He influenced the great Descartes in geostatics, studying the laws of inertia and making the contribution of the path taken by a body going off from a revolving circle, i.e., tangent. In 1553 he reported that bodies in a vacuum fall with the same velocity.

Benedetti’s description of the camera obscura included details on how to make the images appear upright. The material is contained in a printed letter to Pierro de Arzonis. First Benedetti discusses light and the fact that a greater light overshadows a smaller, “just as by day the stars cannot be seen.” He then pointed out that if the light were controlled in a camera the outside images could be seen, but if the rays of the sun were allowed to enter (as by making the opening hole too large) then the images would “more or less vanish according to the strength or weakness of the solar rays.”

Benedetti continued:

I do not wish to keep any remarkable effect of this system a secret from you ... the round opening the size of one small mirror may be filled in with one of those spectacles which are made for old people (but not the kind for those of short sight), but one whose both surfaces are convex, not concave. Then set up a white sheet of paper (as the screen), so far back from the opening that the objects on the outside may appear on it. And if indeed these outside objects are illuminated by the sun they will be seen so clearly and distinctly that nothing will seem to be more beautiful or more delightful. The only objection is that the objects will appear inverted. But if we wish to see those objects upright, this can be done best by interposing another plane mirror.

In the revised and expanded edition of his Natural Magic, Porta gave a more complete description of the uses of the camera. Part of the text was identical with the earlier accounts; part was new.

Ars Magna Lucis et Umbrae, 1646

CAMERA OBSCURA, the natural room camera, was accidentally discovered in antiquity, probably in the Far East. Here is shown an improved version by Giovanni Battista della Porta, 16th Century Neopolitan writer, scientist and showman. A translucent sheet was the screen. The images were upside down and indistinct as no lenses were used. Artists and entertainers found the apparatus of value.

Porta had learned how to make his opening in the single window better by this time—“make the opening a palm’s size in width and breadth and glue over this a sheet of lead or bronze which has in the middle an opening about the size of a finger.” He next pointed out that the outside objects can be seen clearer and sharper if a crystalline lens is put in the opening of the camera as suggested by Barbaro and Benedetti. Porta also mentioned that the insertion of another mirror in the system would make the images appear upright instead of upside down.

Wissenschaftliche Abhandlungen, 1878

JOHANNES KEPLER developed the scientific principles of the camera and its use in astronomy.

But Porta showed himself a real showman by his final word—describing how hunting, battles and other illusions may be made to appear in a room. Here artificial objects and painted scenes were substituted for the natural outdoors as the pictures for the room camera in a method originally suggested by Alberti. Porta said, “Nothing can be more pleasing for important people, dilettants and connoisseurs to behold.”—An early premiere audience of invited guests!

Porta recommended the use of miniature models of animals and natural scenes, the first stage sets for “motion pictures,” with puppet-like characters. He wrote, “Those present in the show-room will behold the trees, animals, hunters and other objects without knowing whether they are true or only illusions.” Porta revealed that he had put on shows of this kind many times for his friends and the illusions of reality were so good that the delighted audience could scarcely be told how the effects were achieved. He also told how the audience could be terrified.

Porta concluded this account with a description of how to use the camera in order to observe an eclipse, something which Bacon or one of his contemporaries had already worked out. Before good instruments were developed, the room camera was an excellent device to save the astronomer’s eyesight and still give him a good view of an eclipse. The giant 200-inch telescope at Palomar in California is closely related to the original use of the camera for astronomical work.

There does not seem to be any evidence that Porta developed a portable camera, the direct ancestor of the modern photographic camera. He also did not appear to have much success with his lenses, as he found the concave mirrors as good as or better than a camera obscura with a lens.

The general subject of the chapter which included the camera was “Herein Are Propounded Burning Glasses” “and the Wonderful Sights to be Seen by Them.” (Recall Archimedes and his Burning Glasses.) Let Porta tell it: “What could be seen more wonderful, than that by reciprocal strokes of reflexion, images should appear outwardly hanging in the air and yet neither the visible object nor the glass seen? that they may seem not to be repercussions of the glasses, but spirits of vain phantasms.”

In a book on refraction, published in 1593, the eye and the camera obscura were compared by Porta. He also covered refraction, vision, the rainbow, prismatic colors (all subjects treated by the early experimenters in optics).

Porta had a great, though mixed, influence. Even in his own mind he did not seem able to decide whether the magic shadows should be used to deceive the public as effects of secret powers or whether they should be used for genuine entertainment and instruction.

After Porta, the “dark chamber” was developed for the use of painters and artists in England and on the continent.