The reply was moderately reassuring. "I believe," wrote Niepce's associate, "he has a rare intelligence for the things that deal with machines and lighting effects; I know he has occupied himself for a long time with perfecting the camera obscura, but I do not know the object of his work. ..." In August of that year, Niepce was in Paris and met Daguerre for the first time. Except for their mutual interest in recording black and white images with the camera obscura, the men seemingly had little in common. Niepce, then 64, had been born to the French aristocracy and was a quiet, reserved man with a sound classical education and an excellent background in science. The French Revolution had sharply reduced his wealth, but he continued to receive enough money from the family estate to enable him to devote most of his time to scientific pursuits. Before he became interested in his black and white photographic process, he and his brother, Claude, had spent some years dabbling with other inventions, including a method for extracting indigo dye and an internal combustion engine. Although they were successful in propelling a boat up and down the Seine and Saone Rivers with the engine, neither invention ever proved commercially feasible.
Daguerre, who was Niepce's junior by 22 years, came from a middle-class family, was largely self-educated and knew almost nothing of science but was nevertheless a remarkably talented and energetic man. Because of his skill at drawing, Daguerre had been apprenticed at the age of 16 to an architect, but he left after three years to become a painter and a stage designer for the Paris Opera. He was also one of the inventors of the enormously popular Diorama. In this spectacle, usually staged in a specially built exhibit hall, famous scenes, such as the interior of Canterbury Cathedral or panoramas of the Swiss Alps, were re-created with three-dimensional effects through the use of translucent paintings and sophisticated lighting. Among his other talents, Daguerre danced well enough to appear occasionally with the corps de ballet at the Opera and was an amateur acrobat with professional competence-tight-rope walking was his specialty.
Despite the dissimilarity in their backgrounds and characters, Niepce and Daguerre apparently liked each other at first meeting. During the next two years, they corresponded about their work and met from time to time to discuss their progress. (The ever-cautious Niepce, however, disclosed few details of his actual methods.) Then, in 1829, Niepce proposed that Daguerre become his partner and engage "in mutual work in the improvement of my heliographic process, and the various ways of applying it, taking a share in the profits that its improvements will permit us to hope for."
Daguerre quickly accepted and then visited Niepce in Chalon to learn about heliogravure and to make plans for the joint project. After Daguerre returned to Paris, the partners never saw each other again. For the next four years, they worked separately and reported on their experiments by mail. Much of their research during this period was focused on the application of iodine, the reddish nonmetallic element that had been discovered in 1811 and was found to form a very light-sensitive compound with silver. But Niepce did not live to enjoy the eventual success of their work. He died of a stroke in 1833, leaving his partner to carry on alone.
On January 7, 1839, Daguerre was finally satisfied with his new black and white photographic process and arranged to announce it before the French Academy of Sciences. Aware of his own lack of scientific training and reluctant to submit himself to questions that might be asked by the Academy members, Daguerre requested a scientist friend to make the actual presentation for him. It was a triumph. The black and white photographs, which the inventor called "daguerreotypes," were examined with awe and enthusiastically praised.