History of Photography

The history of photography is often debated, however the most widely accepted is the assumption that the German chemist, Johann Heinrich Schultz observed that a solution of certain salts of silver darken when exposed to light is widely considered as the beginning of photography. This aspects of certain salts of silver was widely used to create copies of opaque objects. 

It was Thomas Wedgwood, who used paper soaked in silver nitrate in the early 1800s to make images of fern leaves. The area around the leaf struck by light would darken while the leaf’s shadow would remain paper white. This was considered to be the beginning of modern day photography. However unless it was kept in the dark it was impossible to create these photographs.

In 1839, Sir John Herschel, discovered that sodium thiosulphate (hypo) was an effective fixative for the fugitive silver images. It was Sir John Herschel who gave the word photography from the Greek words for light and the act of drawing or writing.

Joseph Nicéphore Niépce is the first person to expose light-sensitive material in a camera in 1826. Niépce used a bitumen-coated pewter plate that hardened under many hours of exposure to light to give an image. He called his images heliographs – from the Greek words for sun and the act of drawing or writing.

Louis-Jacques-Mandé Daguerre worked with Niépce, until the latter’s death, on a process using silver iodide on a polished silver plate. This plate was sensitive than Niépce’s heliographs and required an exposure of about 15 minutes. Development was encouraged by fuming the plate with mercury vapour. The image was then fixed and washed. Daguerre named the process after himself – the daguerreotype. Daguerreotypes are mirror image negatives that only appear as positives when viewed at a certain angle where light reflects from the underlying silver plate.

William Henry Fox Talbot, working in England between 1835 and 1845, was the first to produce prints by what we would know today as a negative/positive process. These are sometimes referred to as talbotypes or, more commonly, as calotypes. Fox Talbot used paper that had been photosensitised with silver chloride, exposed in a camera obscura.

The latent image was developed with gallic acid and fixed with common salt. These resulting paper negatives had reversed tones. Fox Talbot overcame this problem by placing an unexposed sheet of sensitised paper in contact with the first negative and exposing it to light. After developing and fixing, this positive copy gave an accurate tonal reproduction of the original scene. What is more, Fox Talbot could use the original negative to make more than one positive copy. He produced the first commercially printed, photographically illustrated book, "The pencil of Nature", in 1844.

The limitations of Fox Talbot’s paper negatives were swept away by Frederick Scott Archer’s wet plate collodion process in 1851, which itself led to the silver gelatin and dry plates by about 1880. The flexible film we know today came in around 1889, opening up photography to the mass market. All were based on the negative/positive process until the arrival of the digital camera in 1975, itself a black and white-only device that recorded pictures on to cassette tape.

Fox Talbot’s real contribution to photography was establishing the principle of the negative/positive process and demonstrating that one negative could make many copies.

~ Hari Bhagirath Photography