Pinhole Photography
History, Images, Cameras, Formulas by Jon Grepstad
Introduction
Pinhole photography is lensless photography. A tiny hole replaces the lens. Light passes through the hole; an image is formed in the camera.
Pinhole cameras are small or large, improvised or designed with great care. Cameras have been made of sea shells, many have been made of oatmeal boxes, coke cans or cookie containers, at least one has been made of a discarded refrigerator. Cameras have been cast in plaster like a face mask, constructed from beautiful hardwoods, built of metal with bellows and a range of multiple pinholes. Station wagons have been used as pinhole cameras – and rooms in large buildings. Basically a pinhole camera is a box, with a tiny hole at one end and film or photographic paper at the other.
Pinhole cameras are used for fun, for art and for science.
Designing and building the cameras are great fun. Making images with cameras you have made yourself is a great pleasure, too. But in serious photography the pinhole camera is just an imaging device with its advantages and limitations, special characteristics and potentials. By making the best of the camera's potential great images can be produced. Some of the images could not have been produced with a lens.
Characteristics
Pinhole images are softer – less sharp – than pictures made with a lens. The images have nearly infinite depth of field. Wide angle images remain absolutely rectilinear. On the other hand, pinhole images suffer from greater chromatic aberration than pictures made with a simple lens, and they tolerate little enlargement.
Exposures are long, ranging from half a second to several hours. Images are exposed on film or paper – negative or positive; black and white, or color.
Pinhole optics, by the way, are not only used in photography. There is one animal in nature which uses a pinhole for seeing – the mollusk Nautilus. Each eye has an accommodating aperture – the aperture can enlarge or shrink. In this drawing, originally taken from a book published by Arthur Willey in 1900, the eye is the oval opening to the upper right.
History
Early Observations and Experiments
The basic optical principles of the pinhole are commented on in Chinese texts from the fifth century BC. Chinese writers had discovered by experiments that light travels in straight lines. The philosopher Mo Ti (later Mo Tsu) was the first – to our knowledge – to record the formation of an inverted image with a pinhole or screen. Mo Ti was aware that objects reflect light in all directions, and that rays from the top of an object, when passing through a hole, will produce the lower part of an image (Hammond 1981:1). According to Hammond, there is no further reference to the camera obscura in Chinese texts until the ninth century AD, when Tuan Chheng Shih refers to an image in a pagoda. Shen Kua later corrected his explanation of the image. Yu Chao-Lung in the tenth century used model pagodas to make pinhole images on a screen. However, no geometric theory on image formation resulted from these experiments and observations (Hammond 1981:2).
In the western hemisphere Aristotle (fourth century BC) comments on pinhole image formation in his work Problems. In Book XV, 6, he asks: "Why is it that when the sun passes through quadri-laterals, as for instance in wickerwork, it does not produce a figure rectangular in shape but circular? [...]" In Book XV, 11, he asks further: "Why is it that an eclipse of the sun, if one looks at it through a sieve or through leaves, such as a plane-tree or other broadleaved tree, or if one joins the fingers of one hand over the fingers of the other, the rays are crescent-shaped where they reach the earth? Is it for the same reason as that when light shines through a rectangular peep-hole, it appears circular in the form of a cone? " (Aristotle 1936:333,341). Aristotle found no satisfactory explanation to his observation; the problem remained unresolved until the 16th century (Hammond 1981:5).
The Arabian physicist and mathematician Ibn al-Haytham, also known as Alhazen, experimented with image formation in the tenth century AD. He arranged three candles in a row and put a screen with a small hole between the candles and the wall. He noted that images were formed only by means of small holes and that the candle to the right made an image to the left on the wall. From his observations he deduced the linearity of light. (Hammond 1981:5).
In the following centuries the pinhole technique was used by optical scientists in various experiments to study sunlight projected from a small aperture.
The Renaissance and Post-Renaissance
In the Renaissance and later centuries the pinhole was mainly used for scientific purposes in astronomy and, fitted with a lens, as a drawing aid for artists and amateur painters.
Leonardo da Vinci (1452–1519) describes pinhole image formation in his Codex Atlanticus (Vinci, Leonardo, Ambrosian Library, Milan, Italy, Recto A of Folio 337), and Manuscript D (Manuscript D, Vinci, Leonardo, Institut de France, Paris, Folio 8). These descriptions, however, would remain unknown until Venturi deciphered and published them in 1797. The following translation from the Codex Atlanticus, in German, is by Eder (1905:27): "Wenn die Fassade eines Gebäudes, oder ein Platz, oder eine Landschaft von der Sonne beleuchtet wird and man bringt auf der gegenüberliegenden Seite in der Wand einer nicht von der Sonne gotroffenen Wohnung ein kleines Löchlein an, so werden alle erleuchteten Gegenstände ihr Bild durch diese Öffnung senden und werden umgekehrt erscheinen".
In 1475 the Renaissance mathematician and astronomer Paolo Toscanelli placed a bronze ring with an aperture in a window in the Cathedral of Florence, still in use today. On sunny days a solar image is projected through the hole onto the cathedral's floor. At noon, the solar image bisects a "noon-mark" on the floor. The image and noon-mark were used for telling time (Renner 1995:6).
In 1580 papal astronomers used a pinhole and a similar noon-mark in the Vatican Observatory in Rome to prove to Pope Gregory XIII that the spring equinox fell incorrectly on 11 March rather than on 21 March. Two years later, after careful consideration, Pope Gregory XIII corrected the Julian calendar by 10 days, thus creating the Gregorian calendar (Renner 1995:7).
Giovanni Battista della Porta (1538–1615), a scientist from Naples, was long regarded as the inventor of the camera obscura because of his description of the pinhole (lensless) camera obscura in the first edition of his Magia naturalis (1558). His description has received much publicity, as did his camera obscura shows, but he was by no means the inventor.
The first published picture of a pinhole camera obscura is apparently a drawing in Gemma Frisius' De Radio Astronomica et Geometrica (1545). Gemma Frisius, an astronomer, had used the pinhole in his darkened room to study the solar eclipse of 1544. The very term camera obscura ("dark room") was coined by Johannes Kepler (1571–1630). At his time, the term had come to mean a room, tent or box with a lens aperture used by artists to draw a landscape. The lens made the image brighter and focused at a certain distance. Thus this type of camera differed from the pinhole camera obscura used by Frisius in 1544. In the 1620s Johannes Kepler invented a portable camera obscura. Camera obscuras as drawing aids were soon found in many shapes and sizes. They were used by both artists and amateur painters.
During the 19th century several large scale camera obscuras were built as places of education and entertainment. The meniscus lens, superior to the bi-convex lens, improved the quality of the the projected images. Several buildings or towers with camera obscuras remain today: The Camera Obscura at Royal Mile, Edinburgh; the Great Union Camera at Douglas, Isle of Man; the Clifton Observatory at Bristol, England; the camera obscura at Portmeirion, North Wales; the Giant Camera at Cliff House, San Francisco; the camera obscura at Santa Monica, California, the camera on the Mount Oybin in Germany, and others. A few large scale camera obscuras have been built in the 20th century.
The First Pinhole Photographs
Sir David Brewster, a Scottish scientist, was one of the first to make pinhole photographs, in the 1850s. He also coined the very word "pinhole", or "pin-hole" with a hyphen, which he used in his book The Stereoscope, published in 1856. Joseph Petzval used the term "natural camera" in 1859, whereas Dehors and Deslandres, in the late 1880s, proposed the term "stenopaic photography". In French today "sténopé" is used for the English "pinhole". In Italian a pinhole camera is called "una fotocamera con foro stenopeico". In German "Lochkamera" and "Camera obscura" are used. The Scandinavian languages tend to use the English "pinhole" as a model – "hullkamera"/"holkamera"/"hålkamera", though "camera obscura" is also found, and is the term preferred by myself in Norwegian.
Sir William Crookes, John Spiller and William de Wiveleslie Abney, all in England, were other early photographers to try the pinhole technique. The oldest extant pinhole photographs were probably made by the English archeologist Flinders Petrie (1853–1942) during his excavations in Egypt in the 1880s. Two of his photographs are reproduced in Renner (1995:39,40). It should be noted that Petrie's camera had a simple lens in front of the pinhole.
Pictorialism and Popular Pinhole Photography
By the late 1880s the Impressionist movement in painting exherted a certain influence on photography. Different schools or tendencies developed in photography. The "old school" believed in sharp focus and good lenses; the "new school", the "pictorialists", tried to achieve the atmospheric qualities of paintings. Some of the pictorialists experimented with pinhole photography. In 1890, George Davison's pinhole photograph An Old Farmstead (later called The Onion Field) won the first award at the Annual Exhibition of the Photographic Society of London. The award was controversial and led to a schism in the Photographic Society of London (soon to become the Royal Photographic Society) which resulted in the formation of the well-known pictorialist group, the "Linked Ring". George Davison's picture is reproduced in Renner (1995:42), and in some histories of photography, e.g. Michael Langford's The Story of Photography (Oxford: Focal Press 1992. p. 106), The Magic Image. The Genius of Photography, edited by Cecil Beaton and Gail Buckland (London: Pavilion Books Ltd. 1989. p. 79), and Naomi Rosenblum's A World History of Photography (New York: Abbeville Press, p. 310).
In 1892 the Swedish dramatist August Strindberg started experimenting with pinhole photography.About one hundred of Strindberg's photographs are preserved, of these three or four are pinhole images.
Pinhole photography became popular in the 1890s. Commercial pinhole cameras were sold in Europe, the United States and in Japan. 4000 pinhole cameras ("Photomnibuses") were sold in London alone in 1892. The cameras seem to have had the same status as disposable cameras today – none of the "Photomnibuses" have been preserved for posterity in camera collections. Some years earlier, an American company had actually invented a disposable pinhole camera, the "Ready Photographer", consisting of a dry glass plate, a pinhole in tinfoil and a folding bellows. Another American company sold "the Glen Pinhole Camera", which included six dry plates, chemicals, trays, a print frame and ruby paper for a safelight. The very first commercial pinhole camera was designed by Dehors and Deslandres in France in 1887. Their camera had a rotating disc with six pinholes, three pairs of similar sizes. Pictures of these cameras are found in Renner (1995:43).
Mass production of cameras and "new realism" in the 20th century soon left little space for pinhole photography. By the 1930s the technique was hardly remembered, or only used in teaching. Frederick Brehm, at what was later to become the Rochester Institute of Technology, was possibly the first college professor to stress the educational value of the pinhole technique. He also designed the Kodak Pinhole Camera around 1940.
Nick Dvoracek's collection of historical articles
Making a Pinhole Camera
The Pinhole
The most important part of a pinhole camera is the pinhole itself. Precision made pinholes may be bought. You will find a list of sources for pinhole sheets here. For most purposes, however, there is no reason why you should not make the pinhole yourself.
The hole is made in a thin piece of metal, brass shim (available in some car supply stores) or metal from the lid of small box or glass container (bought at a supermarket ). Some use aluminium foil from a disposable baking pan. Ordinary aluminium foil is too thin. My own experience is with brass shim and thin metal from container lids.
If the metal is taken from a container lid, it should be sanded carefully with ultra-fine emery paper (e.g. # 600) to remove any paint or varnish and to make it thinner. The hole is made with a needle. The edge of the hole should be sharp. The optimal diameter depends on the focal length of the camera, i.e. the distance from the pinhole to the film or photographic paper. Some formulas and charts are reproduced below. In general: the smaller the hole, the sharper the image. If the hole is too small, however, the image gets less sharp because of diffraction effects (light is bent around the edge of the pinhole).
Place the piece of metal on top of some hard cardboard. Carefully poke a hole with a needle taking care that the hole is as round as possible. The needle may be put through a cork to make it easier to handle. Or you may put masking tape on the head of the needle. Hold the needle steadily in a 90 degree angle to the surface. Turn the piece of metal and sand the back side carefully with fine-grained emery paper to remove the burr or debris where the needle point has penetrated. (The edges of the pinhole should be sharp). Then place the metal on the cardboard back side up and cautiously spin the needle in the hole to make sure the hole is round. The hole can be checked with a magnifier or an enlarger. You can also use an enlarger or slide projector to check the diameter of the pinhole.