Early Photographic Processes

Photogenic Drawing

1835-1840s

Discovery

Talbot

William Henry Fox Talbot was born in Dorset in 1800.  He was a quiet, shy man, a botanist, linguist, mathematician and inventor.  His mother, Lady Elizabeth Fielding, was an artist.

1834

Talbot honeymooned at Lake Como in Italy in 1834 with his wife, Constance.  There, he attempted to sketch using a camera lucida  -  an instrument that transferred the view before him onto paper. 

But he became frustrated with his sketches and determined, with his knowledge of chemistry, that on his return to England he would find a way to  permanently capture the his image on paper.

He began experimenting with silver nitrate in 1834.

1835-38

Experimenting began in the mid-1830s.  Talbot's success increased over subsequent years as he refined his his photogenic drawing process.  He discovered that it worked best if repeated coats of salt and silver nitrate were given to the paper, and if the paper was exposed before the coating dried.

Exposure times required were typically an hour or longer, so the process was not suitable for taking portraits.

1839

Talbot made no formal announcement of his discoveries until he heard that on 7 January 1839, an announcement had been made in Paris that  LJM Daguerre had discovered a way of fixing a photographic image.

Talbot reacted immediately and wrote a paper on his process that was presented to the Royal Institution, in London, on 31 January 1839 by Michael Farraday.  In fact Daguerre's discovery was quite different from Talbot's

Talbot later invented and patented his Tablotype or Calotype process.  This negative/positive process, was the forerunner to today's conventional photography.

Both the  photogenic drawing process and the subsequent calotype process enabled multiple prints to be produced from a single negative. 

Process

-  Soak writing paper in a weak solution of sodium chloride (common salt).

-  When dry, sensitise the paper by brushing one side with a strong silver nitrate solution.  This causes silver chloride to be formed on the surface of the paper.

-  Take the photo while the paper is still wet.  An exposure of at least an hour may be needed.  This will imprint an image on the paper.

-  Remove the paper from the camera and wash it.

-  stabilise (or 'fix') the image on the paper by soaking the paper in a strong solution of sodium chloride.

-  This produces a negative image on paper.

-  Treat a second sheet of paper with salt + silver nitrate, as above.

-  Lay the negative created above on top of the newly-coated sheet of paper + expose to light.

-  Wait for a positive image to emerge then fix as above.

Result

A salt print retains its original brown colour for only a few hours, then turns purple.

Talbot also experimented with other solutions to stabilise his images.  Images stabilised with potassium iodide are often yellow, and those stabilised with potassium bromide, purple.

Much of Talbot's early experimenting was done with  without the use of a camera - Talbot laying leaves, lace and other items under a sheet of glass placed on top of his coated paper.

The first photograph taken by Talbot using a camera was in August 1835.  The subject was his lattice window at Lacock Abbey. 

Talbot's early cameras produced very small images, less than 1.5 ins. square.  His early cameras were small simple wooden boxes with a lens.   On one occasion, his wife described them as his mousetraps.

The real benefit of Talbot's work came when he announced his Calotype process in 1841.

In Edinburgh 

From 1831 onwards, Talbot had corresponded with a scientific friend in Scotland.  

This was Sir David Brewster who had many links who played an important part in the development of photography in Edinburgh, and became President of the Photogrpahic Society of Scotland, which met in Edinburgh from 1856 onwards.