Ambrotype
The Ambrotype ( Melanotypie , Amphitypie or shortly Ambro , from the Greek word ambrotos "immortal") is a photographic direct-positive method , which in the wet collodion is prepared and has been used from 1852 to 1890; it was mainly used as an inexpensive substitute for the daguerreotype .
Procedure
The image effect of the ambrotype is based on a slightly exposed and developed collodion layer on glass containing iodine and bromide silver . The whitish glass negative is backed with black paper or velvet and thus receives its positive image effect ( false positive ); the negative appears as positive against a dark background due to the dark field principle . A unique piece is used .
History and Development
The method assumed independently undertaken experiments and discoveries by Sir John Herschel (1839), the librarian AA Martin , Frederick Scott Archer (1851) and Peter Wickens Fry ; a first description comes from the book Plain Directions for Obtaining Photographic Pictures by JH Croucher from 1853.
In 1854 the American James A. Cutting patented three process improvements and demanded high license fees for their use; In 1855, Marcus Aurelius Root (1808–1888) coined the term ambrotype .
See also
Other early photography techniques:
- Heliography (1826)
- Calotype (also talbotype ; around 1835)
- Cyanotype (1842)
- Ferrotype (also known as sheet metal photography ; around 1850)
- Collodion wet plate (around 1850)
- Pannotype (around 1860)
- Wothlytypia (1864)
literature
- Wolfgang Autenrieth: New and old techniques of etching and fine printing. From witch's meal and dragon's blood to the photopolymer layer. Tips, tricks, instructions and recipes from five centuries - An alchemistic workshop book 6th edition, Krauchenwies 2010, ISBN 978-3-00-035619-3 ( table of contents , (→ excerpts online) )
- John H. Croucher, Gustave Le Gray : Plain Directions for Obtaining Photographic Pictures. A. Hart, Philadelphia PA 1853 (Reprinted edition. Arno Press, New York NY 1973, ISBN 0-405-04901-3 ).
