File:The American annual of photography (1912) (14579085239).jpg

Identifier: americanannualof1912newy (find matches)
Title: The American annual of photography
Year: 1912 (1910s)
Authors: Gerald E. Jones (1881-1963) Subjects: Photography
Publisher: New York : Tennant and Ward
Contributing Library: Harold B. Lee Library
Digitizing Sponsor: Brigham Young University

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
-mans results were very beautiful and created immense inter-est in the scientific world, although it was later found that themethod was not commercial oh account of the great length oftime necessary for an exposure, and the difficulty of securingperfect results. Another method of direct color photography that may havea great future is the bleach-out process. In this method apaper is coated with a mixture of red, yellow and blue dyesand sensitized by immersing in some chemical which makesthem very fugitive in light. The sensitive dyes only fade inlight of a color different than that which it reflects, thereforethe mixture of red, yellow and blue, which forms black, willfade to the color of any light that strikes it. Where red lightstrikes it the blue and yellow fade, and the same with theother colors. The difficulty with this process is the renderingof the prints permanent by neutralizing the sensitizer, and alsothe fact that it is very difficult to get the three dyes to fadeevenly. 28
Text Appearing After Image:
A PORTRAIT. GERALD E. JONES. Improvements are being made in this process every littlewhile, and we may yet hear of this as the ideal color process.Up to date there have been only two methods that have beenreally commercial. The first is the three-color process that isused by engravers all over the world. The other is the screen-plate method, such as the Autochrome, Dufay, etc. Both are based on the fact that the human eye is sensitiveto only three colors, viz., spectrum red, green and violet. Inthe three-color method, roughly speaking, one negative ismade by red, one by green and one by violet light. Theseplates are then printed in their complimentary or minus colors,red light negative in blue-green, green plate in red of a bluishcast, and the violet plate in yellow. The reason for printingthe plates in the colors mentioned is that through the redfilter all objects that are minus red, or as we call it, blue,photograph black. Therefore, wherever there is any blue inthe subject it is au

Note About Images