Many years ago – the 1830′s to be vague, a man experimented with chemicals whilst also studying optics and the colour of flames. He had a history of experimentation having blown himself up several times at school – a fact that did not prevent his headmaster from recording that he would go far if he continued his scientific studies. By 1830 he had written a dissertation on Coloured Flame suggesting that the colours produced when different substances were burnt were due to their atomic structure – an assumption that would eventually prove to be true as others worked on the perodic table of elements. He also wrote about Monochromatic Light – although it is doubtful that he had ‘seen the light’ at that stage regarding what was to become his major achievement.
In the 1820-30′s two Frenchmen, Dageurre and Niépce worked together to create a means of capturing an image of the view seen through a camera – something only previously done by painstaking drawing. Eventually, they discovered that silver iodide could be exposed to the light to capture such an image though sadly Niépce would die in the very year that one was finally produced – 1833. Dageurre continued to perfect the process which he announced to the world in 1839. The images produced by their process became known as Daguerreotypes and remain some of the best early photographic images.
Unknown to Dageurre and Niépce in England William Henry Fox Talbot was also working towards permanently capturing images from cameras. His early experiments with saltpeter and chemicals suitable for blowing himself up now bore fruit in an understanding of the properties of Silver Iodide, Gallic Acid and Silver Nitrate. However, his final work was rushed when Daguerre went public in 1839. Forced into the open Fox Talbot presented evidence of his work dating back to 1834 to The Royal Society and followed it up with technical details later the same year. This often happens in science, if one person publishes it becomes necessary for another working in the same field to publish in order to ensure that their work is not passed over. A good example was Charles Darwin who was forced to publish his Evolution theories on the advice of Huxley after reading the thoughts of Wallace.
So two processes appeared that would capture an image from a camera and in a short time they would be joined by a third. We had the Daguerreotype. Fox Talbot christened his Calotype – though it was also known as Talbotype. In 1851 Archer’s collodion process would become the third. The Daguerreotype and Collodion processes had one big advantage over Talbot’s Calotype – the images held far greater detail as they were created and fixed on a plate of steel or glass. Daguerre’s process had one major disadvantage – it was one shot. The image produced was not reproducable. The Collodion process also had a major disadvantage in that the plate was coated with wet chemicals, the photograph taken, and the images fixed – all in around 15 minutes. Once the chemicals started to dry out the ability to make an image was lost, so the photographer had to carry around a portable dark room! Calotype had its disadvantages also – the negative was ok but the image had to be created as a positive on sensitized paper – initially as a contact print. Needless to say the grain of the paper took away much of the detail within the image.
Over a couple of decades though, each process was improved. Daguerreotypes proved to be a Darwinian evolutionary dead end – without the possibility of making several copies of an image they passed out of common use very quickly and were commercially dead by 1860. The Collodion process remained in common use for longer though efforts to make it a dry process were never entirely successful – it remains a minority interest today especially among those photographers trying to recreate 19th century scenes. Despite its short comings the Calotype process became the accepted standard for commercial photography. It’s key advantages were ease of use and the ability to make as many copies from one image as you wished. Over time Negative film improved and special photographic papers were developed to make the results better. Even in today’s digital era it is still used commercially and by enthusiastic amateur photographers. You can now choose your film stock and paper to enhance your intended artistic result. I wonder if Fox Talbot anticipated that?
The National Trust at Lacock Abbey houses an exhibition about William Henry Fox Talbot and his work. It also stages photographic exhibitions.
For proper detailed descriptions of each type of process please visit Wikipedia