Posted on Friday 9 January 2004 to Visions and Illusions

Fixing the image - the early days of photography

In 1780, an eccentric Frenchman, Professor Charles, a builder of hot-air balloons and a lecturer in physics at the Sorbonne had already made elementary photographs on paper impregnated with silver chloride by casting through sunlight the silhouette of a man. In this way, the image of the silhouette was engraved in white on the paper, but after a few moments the light started to have an effect on it again until it made it disappear. Researchers from the principle European countries embarked on a mission to see who would be the first to come up with a solution to the problem. James Watt in Scotland, the inventor of the steam engine, was one of them. But the weak images on silver solutions that he obtained with the camera obscura, disappeared very quickly. Wedgwood, and later Humphry Davy, persevered further, but still had no success. On these experiments Humphry Davy wrote:

"What is needed is to somehow prevent the light parts of the drawing being affected by daylight. If this were achieved, the process would be as useful as it is straightforward. Up until now you have to keep the copy of the drawing in a dark place. This drawing can only be viewed in the dark and for a short time. I have tried in vain all possible means to prevent the colorless parts from going black with light.

"As for the images produced by the camera obscura, undoubtedly they did not get enough light for me to obtain a clear drawing with the silver nitrate. Nonetheless this is where the research interest lies. But all attempts have been useless."

It did not occur to Davy that the silver nitrate emulsion was not sufficiently sensitive to record the images that were being produced inside the camera.

In 1805, in Ciudad Real, now known as San Cristóbal de las Casas, in Chiapas, Mexico?which was then part of Guatemala?Don Enrique Martínez, a chemistry and festive firework enthusiast, experimented with the camera obscura and a silver chloride solution applied to a metal plate. The local historian, Don Prudencio Esponda, describes Martínez's experiments in the following way:

"With his mysterious dark box, the learned professor Martínez has managed to retain a replica, similar to a very beautiful drawing of the front of the temple of Santo Domingo, on a metal plate impregnated with chemical products which he invented. When he removed the above-mentioned replica from the dark, from the aforementioned box, he rubbed it with a compound of lime juice and other vegetable juices. In this way, the image lasted for some days during which the most important residents of the town could admire it."

Don Enrique Martínez could not continue his interesting experiments, as in January 1806 he died in a terrible explosion accidentally set off in his firework factory. Nevertheless it was unlikely that even if he had continued to live, despite having made remarkable discoveries, that these should have become known, given that the distant province in which he lived was totally isolated from the important cultural centers.

In 1822, Necèphore Niepce, a French chemist, succeeded in making the first permanent image employing silver iodide. Using a camera obscura bought from a manufacturer called Chevalier he achieved, after an eight-hour outside exposure, the image that from then on is known as the Set Table.

source: From the Camera Obscura to Cinema - Carlos Jurado