JOHN HERSHEL

John Hersel was born on the 7^th March on 1792 in Buckinghamshire, England. He was an Astronomer, Mathematician and a Photographer, as an astronomer he is remembered as the discoverer of many moons of Saturn. Hershel had most of his education at Eton and was even under the tuition of a private tutor until he was of age 17 where than he was sent to study at St. John’s College, Cambridge. In 1813 Hershel graduated as a senior wrangler and won the highest academical distinction from his year.

He was the inventor of the photography process known as the Cyanotype process, or better known as the blue print; this technique was still in use for the printing of buildings plans just until a few decades ago. The Cyanotype process involved the use of hyposulphite of soda to fix the pictures, iron salts was used to coat the paper and prepare it for contact printing, finally the process needed the washing of the paper with water to obtain a white image onto a deep blue background. John Hershel is also renowned as the man that gave the word of photography as we know it nowadays and also the words negative and positive where from his creation.

An experimental cyanotype of an engraving of a lady with a harp, by Sir John Herschel

An example of a building plan blue print

Hershel had a very positive personal life; he was always ready to lend a helping hand to who ever needed his experience in scientific studies, where he always encouraged people much lower than his level. He died on the 11^th of May 1871.

NNDB tracking the entire world, 2013. John Hershel. [online]

Available at: < http://www.nndb.com/people/054/000086793/ > [Accessed 22 October 2013].

Alternative Photography, 2000. Cyanotype history – John Herschel’s invention. [online]
Available at: < http://www.alternativephotography.com/wp/history/cyanotype-history-john-herschels-invention > [Accessed 22 October 2013].

THE DAGUERREOTYPE

The daguerreotype got its name after its inventor Louis-Jacques-Mande’ Deguerre, who was a French man, however this final process was a result from a previous collaboration in business with French man Nicephore Niepce. Unfortunately Niepce died from a stroke and it was there that Mande’ continued to work until he came out with his Daguerreotype process.

Daguerreotype of Louis Daguerre in 1844 by Jean-Baptiste Sabatier-Blot

His representative officially announced and made the process public in 1839 during the French Academy of Sciences meeting in Paris. It immediately went viral throughout the world especially in the United States, due to its possibility of capturing a faithful image of the object photographed. The general public could have there own portrait taken and it was more accessible and affordable to almost practically every citizen, unlike before where in order to have a faithful portrait reproduction, one must have sought the service of a painter of which charged much higher prices and required a relative sustainable amount of time to produce the painting. It was estimated that just in New York existed 70 Daguerreotype studios by 1850.

This daguerreotype is the earliest known photograph of Abraham Lincoln, taken at age 37 when he was a frontier lawyer in Springfield and Congressman-elect from Illinois

The process to produce a Daguerreotype was quite simple yet a great amount of care was needed; it consisted in the creation of a detailed image onto a copper plated sheet, which was also coated with a thin coat of silver. First most the sheet needed cleaning and polishing until a mirror effect was achieved, than the plate had to be sensitized with iodine and become yellow in appearance. From there the plate would be placed in a light proof pocket and placed into the camera itself, the exposure was made and the next step was to develop the plate with hot mercury vapor till the image becomes visible. A solution of sodium thiosulfate or salt was placed over the plate to fix the image, than it was toned using cold chloride. These final images where unique as they couldn’t be reprinted, however they could have been reproduced by reapplying the same photographic technique to an already produced daguerreotype.

The Library of Congress, 2002. Daguerreotype Photographs: The Daguerreotype - American Memory. [online] Available at: <http://memory.loc.gov/ammem/daghtml/dagdag.html > [Accessed 16 October 2013].