Ok so next we have to talk about its creator William Henry Fox Talbot. Talbot used to complain about the camera Obscura "the faithless pencil had only left traces on the paper melancholy to behold" Talbot 1833. Talbot created the Calotype in 1841. A piece of paper was brushed with weak salt solution, once it was dried it was then brushed with a weak silver nitrate solution then dried again making silver chloride in the paper.
Once this process was done it has been made sensitive to light, and is now ready for exposure. This takes half an hour, giving a print image. It was then fixed in a strong salt solution potassium iodide of hypo. The following year he discovered by adding gallic acid, the paper would become more sensitive to light. Because of this it was no longer necessary to expose until the image became visible. Also with further treatment of gallic acid and silver nitrate the image was developed.
Even though the Calotype was popular it could not compare to its rival Daguerreotype, the reason being the following
- its popularity due to patent restrictions
- the materials was less sensitive to light
- imperfections of the paper reduced the quality of the final print
- the process itself took longer, it had two stages
- prints would fade.
Over all the Daguerreotype produced a better image then the Calotype
Now let me tell you alittle bit about Talbot. William Henry Fox Talbot was born February 11, 1800. He was the only child for his parents, his father died when he was 5 months old. His mother remarried and gave him two half sisters. Talbot went to Harrow School in 1811 and then entered Trinity College, Cambridge, in 1817. He became a Scholar in 1819. He then won the Porson University Prize in Greek verse in 1820. He then won the second Chancellor's Classical Medal. Following this he processed with his M.A. in 1825.
Sources
http://www.rleggat.com/photohistory/history/calotype.htm
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