The Camera Story (Early Processes)

What follows below, and in the following two posts is an overall history of photography beginning with the camera obscura, and the earliest attempts to record visible images on chemically treated surfaces. The earliest processes were the Daguerreotype and the Calotype. From here we move on to the Wet Plate Process pioneered by Frederick Scott Archer in England. It is only when we come to gelatine plates and films in the third post from here that the reader will find a reference to the arrival of the box camera....


THE ORIGINS OF PHOTOGRAPHY can be traced to an early optical device known as the camera obscura. Known even during the times of Leonardo da Vinci, the camera obscura, like the pinhole camera, was simply a darkened room with a tiny hole at one end to admit light. Rays of light from a brightly lit scene outside passing through gave rise to an upside down image that could be seen projected onto the wall of the room.

Light from a scene passing through a lens was reflected
upward by a mirror as shown, giving rise to an image on
a ground glass or sheet of tracing paper.

Later improved versions of the camera obscura utilized a positive power lens in place of the hole in the wall. This gave a brighter and far more clear image. Portable types of the instrument were in common use in the 17th and 18th centuries and were an invaluable aid to artists and painters in tracing out on paper perspective views of outdoor scenes.

The camera obscura used by the ancients embodied within it the principle of the photographic camera but was lacking, as yet, in one essential ingredient : and this was a means by which a permanent record could be made of the scene projected by the lens.

Modern film photography depends for its success on the fact that certain chemicals, most notably the bromide and chloride of silver, are affected by light (such as the image produced in a camera obscura) and the pattern of light and shade can be rendered visible by a series of appropriate manipulations involving treating the film with chemicals. Although straightforward enough, this principle long eluded capture. Amongst the first to investigate the action of light  on chemicals was the German scientist Johann Heinrich Schulze who showed in 1725 that a solution of silver nitrate and chalk held in a glass bottle darkens when placed out in the sun. Almost three quarters of a century later, Thomas Wedgewood, son of Josiah Wedgewood, the founder of the pottery empire, made an interesting experiment in which leaves and other botanical specimens were placed over paper moistened with silver nitrate. When left in the sun, the border which received light darkened leaving a clear silhouette of the opaque object.

Although working in collaboration with Sir Humphry Davy, Wedgewood’s experiments were to remain only a scientific novelty; his ‘sun pictures’ were of little value, the whole of the sheet darkening to a uniform shade when held under light for viewing.

As is now known, Wedgewood’s experiments failed because he was unable to ‘fix’ his images : after he had made a picture of a specimen, the clear white areas of the silhouette still contained silver nitrate, and was thus susceptible to darkening under light. Today’s photographers fix their pictures, i.e., render them stable under the further action of light using a solution of sodium thiosulphate, commonly known as hypo. But we are here looking at early history in the eighteenth century when the principles that underlie the photographic process were in the early stages of discovery, when each tiny element ranging from creating an optical image to forming a permanent record on a light sensitive surface and arranging things to the photographer’s convenience presented enormous difficulties which could be worked out only by years of painstaking research and experiment.

The first person to succeed in creating a permanent image using a camera obscura was a Frenchman named Joseph Nicephore Niepce, and for this reason France is often regarded as the birthplace of  photography. An amateur scientist, Niepce was experimenting as early as 1816 with a camera obscura hoping to record a picture on a chemically treated stone. After many experiments, he finally used bitumen spread over a pewter plate as his sensitive surface and succeeded in obtaining a positive picture in a camera obscura showing the view from his window. This crude photograph requiring a camera exposure of about eight hours is the world’s first photograph taken in a camera and is still in existence today.


Louis J. M. Daguerre.

Moving on further, we now come to Daguerre. Louis Daguerre was a contemporary of Niepce and worked in the show business, staging dioramas in Paris and elsewhere—public shows featuring large painted backdrops accompanied by spectacular lighting effects. Daguerre had used camera obscuras to make sketches for his dioramas and he soon interested himself in recording camera images using silver compounds. He had heard of Niepce’s experiments from the Parisian optician Charles Chevalier who supplied lenses and camera obscuras. Daguerre wrote to Niepce and the two went into partnership to pool their knowledge and help develop a suitable process, but Niepce died four years later and little came of this collaboration.

Daguerre, as enthusiastic as ever, now embarked on a long series of experiments on his own. Unlike Niepce, he finally turned to silver coated copper plates sensitized with iodine. With the equipment then available, this seemed to be a promising method, but the plates were too slow to record a visible image. Daguerre finally hit upon success when he accidentally made the discovery that the picture, invisible as yet, could be ‘brought out’ (or developed) by holding the exposed plate over mercury vapour.

Daguerre’s invention was made public in 1839 and became an instant success worldwide. The first successful portrait in America using this method was of Miss Catherine Draper; it was made in 1840, requiring an exposure of about 6 minutes with the sitter’s face dusted over with powder to keep the time to a minimum ! In France, America and other parts of the civilized world, Daguerrean galleries opened. These were studios with posh waiting rooms where people would flock in large numbers each eagerly awaiting his turn to ascend the steps to the glass-house camera room above. Daguerre’s original process required an exposure of around 5-12 minutes, but a special portrait lens designed by Petzval brought this down to about a minute or two. The daguerreotype, as it was known, was a thing to marvel at; the tiny image measuring 5 inches by 7 inches had a shiny mirror like appearance and showed up every tiny detail with the greatest clarity. Demand was so great that in 1853 it is estimated that over three million daguerreotypes were made in the United States alone. Daguerreotyping was a profitable business and huge fortunes were made by owners of studios in those days.


Fox Talbot.

While the world was witnessing the marvel of the daguerreotype, a quiet revolution was taking place in England. William Henry Fox Talbot, landowner and amateur scientist, found himself fascinated with the camera obscura and began his own experiments trying to record a scene on sensitized paper. Talbot began by first making ‘sun pictures’ or silhouette images, but unlike Wedgewood, he discovered that he could ‘fix’ (i.e., prevent from darkening further) his pictures by bathing the paper in salt solution.

Talbot next tried making pictures in a camera obscura. By 1842 he had devised a satisfactory method of obtaining a negative. His procedure consisted of coating good quality writing paper with silver iodide solution, then exposing in a camera for 2 – 3 minutes after the paper had dried (the word obscura was generally dropped from this time). No visible change had occurred on the paper at this stage. The picture was then ‘brought out’ (or developed) by immersing in gallic acid, fixed in hypo, and finally washed and dried. The resulting image was a negative of the scene.

The next step was to lay the negative in close contact with another sensitized sheet, allowing sunlight to shine through till a brownish image appeared, this time a positive. The print was fixed, washed and dried and was finally ready for viewing.

Talbot had thus invented the negative-positive system of photography. He named his process the ‘calotype’; it possessed the distinct advantage that once a negative was realized, any number of positive prints could be cheaply produced. Despite this advantage the calotype could never compete with the daguerreotype in terms of popularity, mainly on account of the fact that results lacked overall sharpness, often showing up the mottled appearance of the paper negatives employed. Aware of its limitations as a photographic process, Talbot publicized his process by mass producing a large number of excellent prints which were put up for sale. Despite the publicity, the calotype continued to remain mostly a neglected process having had a brief spell of success in Scotland where the painter David Octavius Hill in collaboration with Robert Adamson produced some of the most remarkable portraits ever made.

Continued below.