Items related to Collodion Emulsion and Its Applications to Various...
Collodion Emulsion and Its Applications to Various Photographic and Photo-Mechanical Purposes with Special Reference to Trichromatic Process Work - Softcover
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1905 edition. Excerpt: ...work softer than the usual hydroquinone developer, and glycin is recommended. (See page 40). If the original is of a red or brown colour, it is advisable to use a collodion emulsion sensitized with ethyl violet. Dissolve 1 part of ethyl purple 6B in 500 „ of alcohol. Filter and add to every quart of emulsion 25 ccm. of above solution. This emulsion is red-sensitive and must be handled in green light. The plates are to be washed before exposure. Negatives made with this emulsion are soft and full of detail in the shadows. A yellow orange screen can also be used if, for instance, the object to be photographed is of a blue or violet colour. Typewritten letters or blue prints can be successfully reproduced in this way. B.--CONTINUOUS TONE REPRODUCTION OF COLOURED OBJECTS IN MONOCHROME. The same course is taken as in the foregoing chapter, except in the case of a painting containing much orange and red, where a more panchromatic rendering is requisite. In conjunction with the above described emulsion a yellow screen must be used. The density of this light filter will be entirely governed by the character of the object, but for a general guidance we may point out the following conditions. A yellow light filter should absorb the violet blue rays which the original reflects, and, by virtue of this retarding action of the filter on blue and violet in general, this permits of a longer exposure of the yellow, green and orange parts of the picture, which will be therefore reproduced in a lighter tone. It follows that, the deeper the filter the longer will be the exposure, and the lighter the rendering of the greens, yellows and probably orange parts of the picture. A yellow filter suitable for the work can be made by bathing well-selected...
"synopsis" may belong to another edition of this title.
- PublisherRareBooksClub.com
- Publication date2013
- ISBN 10 1230169237
- ISBN 13 9781230169231
- BindingPaperback
- Number of pages28
(No Available Copies)
Search Books: Create a WantIf you know the book but cannot find it on AbeBooks, we can automatically search for it on your behalf as new inventory is added. If it is added to AbeBooks by one of our member booksellers, we will notify you!
Create a Want