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In the web article Daguerre’s manual you can read a summary of the original instructions for making the earliest variant of the process.
about Daguerre’s manual
The publication of Daguerre’s Description practique du procédé nommé le Daguerréotype was big news. Interest in the treatise was so overwhelming that it was reprinted several times, not always with Daguerre’s permission. In combination with the required equipment, certified by Daguerre himself, they sold like hot cakes.
great success
The dissemination of the revolutionary medium occurred relatively rapidly for those times: in such countries as the United Kingdom, Belgium, the Netherlands and present-day Germany and Hungary, the process was already introduced in 1839 or early 1840. Samuel Morse, the inventor of Morse Code, introduced the medium to the United States in 1839. It was there in particular that the daguerreotype had a large number of fanatical practitioners within a short time. Professional studios were established in various cities, also in the Netherlands.
Label of a Daguerreotype establishment, ca. 1845 | Collection Prentenkabinet, University of Leiden.
capable of improvement
As a result of this fast dissemination, many experiments were made to further perfect the process. Some elements were indeed capable of improvement. The medium was unsuitable for making portraits, for example. The average duration of an exposure was ten minutes, sometimes longer. Many people found the absence of colour disappointing. The vulnerability of the image was also a problem.
All eyes were directed at Daguerre, who had announced that he was doing research and would make a number of improvements public. To the wrath of a large number of interested parties, however, he failed to keep his promise.
light intensity and light sensitivity
Ways to drastically reduce the duration of an exposure had already been invented by others in 1840 and 1841.
Such as:
- the use of a large-aperture lens, particularly the Hungarian Peztval lens by Voigtländer
- the applying of several light-sensitive layers, such as bromide and chloride in addition to iodine
- adaption of the studio interior, such as mirrors for directing light and blue windows (the light-sensitive layer was more sensitive to blue light). Such developments meant that exposure time could be reduced to less than half a minute.
Voigtländer camera with Peztval portrait lens, 1841 | George Eastman House, Rochester
gold toning
The most radical improvement of the process was the ‘toning’ of the plate with a gold solution. For this, the plate was first fixed and then submerged in a warm bath of water and gold chloride. Since its invention in 1840 this method became a standard part of the process. Gold toning led not only to a much greater stability of the image, but also more clarity, so that the image came across more strongly. Otherwise than the word ‘gold toning’ would lead one to surmise, there is no evidence of a gold colour.
perfect gloss
Various other improvements followed. These concerned such things as the preparatory treatment of the plate. Plates were initially manufactured by means of a roll. From 1850 onwards it was possible to galvanise them, whereby a purer layer of silver could be applied by means of an electric current. Special polishing equipment made its entry, which could provide the plate with a perfect gloss. Daguerre’s method of polishing produced a dull effect as the polishing lines were clearly visible running in circles. The new equipment enabled polishing to be done in a horizontal or vertical direction only. Sometimes the lines are invisible to the naked eye.
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