- When
news of the imminent publication of the Daguerreotype pro-
- cess
reached England, William Henry Fox Talbot [1800-1877] of La-
- cock
Abbey was shocked. For years he had conducted his own re-
- searches
into permanently fixing the camera image. The process
- he
discovered involved the use of a paper negative from which an
- unlimited
number of prints could be made. Alarmed by the news
- from
Paris he hastened to publish his findings and have his inven-
- tion
patented under the name of »calotype«.
Fox
Talbot's »calotype« [Greek for
»fine print«] required exposures of about - 30
sec to produce an adequate image on the negative. Like the Daguerreotype
- it
was announced in 1839. Within three years the exposure time in both pro-
- cesses
had been reduced to several seconds.
Read
more about Fox Talbot and - his
research
Fox
Talbot had discovered that paper coated with silver iodide could be made
- more
sensitive to light if dampened before exposure by a solution of silver
ni-
- trate
and gallic acid, and that the solution also could be used in developing
the
- paper
after exposure. After development, the negative image was made per-
- manent
by immersion in sodium thiosulfate, or hypo.
Read
more detailed Technical Notes - on
the Calotype Process
-
Click
image below to view some of the equipment used by Fox Talbot and - other
calotypists of the era at the Museum of the History of Science, Ox-
- ford
University, UK
