Henry Fox Talbot - Salted Paper and Calotype Processes
William Henry Fox Talbot (1800 - 1877) was a British landowner, scientist, archaeologist, politician and a photography pioneer who invented the calotype
process, one of the earliest photographic processes.
Talbot was born on 11 February 1800 to f William Davenport Talbot, of Lacock Abbey and Lady Elisabeth Fox Strangways and was their only child. He was very
educated and went to Rottingdean, Harrow School and at Trinity College, Cambridge. At Trinity College he received Porson prize in Classics in 1820 and a
year later he graduated as twelfth wrangler (a student who gains first-class honors in the third year of the University's undergraduate degree in
mathematics). He published scientific works from 1822 to 1872, many of them on mathematics. He began his experiments in optics very early and they led them
to photography. He was also a politician. He supported the Whig Ministers and he was a Member of Parliament for Chippenham between 1832 and 1835. After
that he retired from Parliament but in 1840 he held the office of High Sheriff of Wiltshire. He engaged in the field of Assyriology for 20 years as an
archeologist. He was one of the first decipherers of the cuneiform inscriptions of Nineveh, together with Sir Henry Rawlinson and Dr Edward Hincks, and he
wrote a few works on archeology.
Talbot began his experiments in photography 1934 and by 1841 he discovered calotype or talbotype process when he patented it. This process used paper
covered with silver iodide while the other methods used metal plates at the time. This produced a translucent original negative image and allowed for
multiple positives to be made by contact printing. This was better than a daguerreotype which was popular at the time and produced opaque positive and
which could be copied only by photographing it again. Calotype used gallic acid to develop the latent image. Talbot described his process in his book “The
Pencil of Nature” in 1844 and for this Royal Society awarded him with Rumford Medal which is given for “an outstandingly important recent discovery in the
field of thermal or optical properties of matter made by a scientist working in Europe”.
Calotype was improvement on works of John Herschel and Thomas Wedgwood. It used silver iodide instead of silver chloride and a different developing agent
gallic acid and silver nitrate. This shortened exposure time from hours to just few minutes and made photography much easier to use.
But, everything wasn’t perfect. As we said Talbot patented calotype in 1841. Before him, Daguerre gave his daguerreotype “free to the world” (everywhere
except England) and, at that time, patent holders were attacked for enforcing their rights. Talbot sold individual patent licenses for £20 each when he
began selling them, only to later lower his fee to £4 or even free for amateur and £300 annually for professionals. He thought that he is in his rights
because he spent thousands of pounds while developing the process but the general public was of no such opinion. In 1852, Lord Rosse, the President of the
Royal Society, and Charles Lock Eastlake, the president of the Royal Academy, wrote an open letter to Talbot and published it in The Times. In it, they
called Talbot to give up on patent rights for calotype because they thought that it slows down development of photography. Talbot agreed but not completely
and he stopped charging licensing fees for amateurs but continued to charge professionals. When he wanted to extend his patent in 1854 he filed a lawsuit
against one of the photographers. Unhappy with how lawsuit went he decided to give up on the patent and not extend it.