The process of making photographic negatives on paper using silver salts is one of the earliest photographic techniques, preceded only by Nicéphore Niépce’s method and pre-dating the Daguerrotype by at least 6 years.
In Brasil, the painter and inventor Hercules Florence, working together with the chemist Joaquim Correa de Mello, succeeded in fixing silver-based images from a camera obscure in 1833.
At the same time, in England, the polymath gentleman-of-leisure, Sir William Henry Fox Talbot, made experiments in the mid 1830s along similar lines. His first successes were made using silver chloride and required very long exposures - at least an hour outdoors. He improved his technique using silver iodide which reacts faster to light and named this process the Calotype. Talbot’s earliest surviving image, of an oriel window at his home, Lacock Abbey, dates to 1835.
Having patented his technique in England and France, Talbot, together with a French entrepreneur the marquis de Bassano, set up a school in France in 1843 in an attempt to monetise the invention. The school, grandly named l’École Normal de Photographie, was set up at Place du Carrousel in the Louvre. However, it all ended by October that same year. But the cat was out of the bag and there were now a cohort of French practitioners.
In England the Talbot patent held back the development of photography for a decade. However, in Scotland, where his patent did not hold sway, a group of calotypists in the circle of Sir David Brewster at the University of St Andrews were prolific during the 1840s. This included the famous partnership of painter David Octavius Hill and Robert Adamson. The latter had trained in engineering but set up one of the earliest photographic studios anywhere at Rock House on Calton Hill in Edinburgh. Together, from 1843, they produced a huge body of work in the few short years before Adamson’s untimely death in 1848.
The French were not held back by the patent because the French courts upheld what was essentially the plagiarism of Talbot’s technique both by Louis Désiré Blanquart-Evrard and Dr Jacques Guillot-Saguez in their separate publications of 1847. Notwithstanding the legal disputes, the circle of French calotypists grew, starting with Victor Regnault and Gustave Le Gray. From 1848 Le Gray ran his school at Barrière de Clichy and his students include the greatest names from the earliest French photography: Henri Le Secq, Charles Nègre, Maxime du Camp, comte Frédéric Flacheron, Mestral, Léon de Laborde, Félix Reynard and many others.
In 1851 La Commission des Monuments Historiques made the first large-scale photographic commission by a government when they sought photographers to travel throughout France to photograph buildings of antiquity with a view to prioritising remedial works. So in the summer of 1851 five accomplished French photographers, Le Gray, Mestral, Hippolyte Bayard, Henri Le Secq and Édouard Baldus set off in different directions and produced a large body of principally calotype negatives. The images they brought back were more works of Fine Art than documentation of the material state of the buildings and ended up forgotten and sitting in a drawer for almost 130 years until they were rediscovered and exhibited.
The French continued improving the paper-negative process even after Gustave Le Gray’s waxed-paper process. As late as 1879, Arsène Pélegry published “La photographie des peintres, des voyageurs et des touristes” in which he describes what is probably the ultimate version of the process, building upon all that went before - a dry paper process that is convenient and whose light-sensitive papers have a shelf-life of beyond a year.