Category:Photographic processes dating from the 19th century
This category includes processes that date from the 19th century. Some lasted into the 20th century, some into the 21st; others were extinct within a decade.
Subcategories
This category has only the following subcategory.
H
- History of platinum printing (6 P)
Pages in category "Photographic processes dating from the 19th century"
The following 40 pages are in this category, out of 40 total. This list may not reflect recent changes.
C
D
P
T
https://en.wikipedia.org/wiki/Category:Photographic_processes_dating_from_the_19th_century
The Collodion-Albumen process is one of the early dry plate processes, invented by Joseph Sidebotham in 1861.
The process lacked economical success because the plate was much less sensitive (about 1/4)[clarification needed] and tended to have harder contrasts than wet plates. While the first was acknowledged by Sidebotham, the latter were disputed by him indicating the fact that the 1860 gold medal for the best landscape photography was made with a Collodion-Albumen plate (Recreative Science, 1861 P 43).
Why does it work?
There are several compounds unstable to light in this mixture, mainly silver iodine and silver bromide. These decompose and leave silver that is oxidized by the developer (Pyrogallic Developing Solution). The excess of silver iodine and silver bromide are stabilized by the fixing bath. The albumen mixture just encloses the Collodion in a dry environment.
Sources
- The Collodio-Albumen Process of Photography, Joseph Sidebotham (London : Recreative Science Vol II 1861)
- History of Photography, Josef Maria Eder (Dover Publications, Mineola, NY, 1945)
 | This photography-related article is a stub. You can help Wikipedia by expanding it. |
https://en.wikipedia.org/wiki/Collodion-albumen_process
https://en.wikipedia.org/wiki/Gelatin_silver_process
https://en.wikipedia.org/wiki/Silver_bromide
https://en.wikipedia.org/wiki/Silver_iodide
No comments:
Post a Comment