|by Leigh Forbes||Monday, 17th August 2015|
In the UK, the invention of photography is popularly attributed to Henry Fox Talbot, of Lacock in Wiltshire (now owned by the National Trust, and housing a fabulous museum). However, Fox Talbot invented only one of the many processes devised for the long-term preservation of photographic images, and not photography itself.
The origins of such image capture – using of light-sensitive material to absorb an image projected upon it – came in 1800, when Thomas Wedgwood (son of Josiah Wedgwood [of china-plate fame], and uncle of Charles Darwin) used leather coated in silver nitrate to capture images projected from a camera obscura. The resultant silhouettes, termed “photograms”, were not “fixed”, and quickly faded. The need then was to find a way of securing the images, so they would remain visible in the long-term.
By 1822, Nicéphore Niépce had devised the “heliograph”, which incorporated light-sensitive chemicals combined with the use of acid to etch away unexposed (i.e. unhardened) material, leaving a permanent image behind on a solid base. In 1826 or 1827 he used a photographic base “plate” of pewter, coated with bitumen that had been dissolved in lavender oil, to produce what is now considered to be the oldest surviving photograph: “View from the Window at Le Gras” (see below), in an exposure that took so long (perhaps days) that the buildings are illuminated by sun from both the left and right-hand sides.
After Niépce died in 1833, his colleague in Paris, Louis Daguerre, continued experimenting until, in 1839, he could publicly announce his invention of the “daguerréotype”. This new process involved sheets of polished copper, coated in silver-iodine, to be exposed first to light (to capture the image), then to mercury vapour (to chemically ‘develop’ the image), and finally to be washed with salt water (to remove any remaining light-sensitive silver), and thus “fix” the image. The use of mercury vapour – to reveal an otherwise thought-to-be-underexposed image – allowed for much shorter exposure times.
Back at Lacock, Fox Talbot didn’t know about Daguerre’s experiments until the public announcement, which deprived the Englishman of all the glory. And not only did Daguerre get there first, but his techniques were superior: although Fox Talbot had discovered a similar process for capturing images (using paper coated with silver chlorine), he relied on very lengthy exposure times to produce a visible image (albeit without additional chemical development), and could not compete commercially with Daguerre. Fox Talbot’s later “calotype” process did reduce exposure times (by embracing chemical development), and his invention of the “negative” allowed multiple copies to be made from one master image, but his methods still could not rival the fine detail produced by the daguerréotype.
It’s perhaps just as well that Daguerre got there first. While Fox Talbot applied for patents and licensing rights to protect his work – thus stifling progress in the UK for many years – Daguerre, in an 19thC version of an open-source release, gifted his invention to France, ensuring others could build on his discoveries, and advance photography at a very much faster rate than might have otherwise been possible.
Check out my photography board on Pinterest: