Identifier: halftoneprocessp00verf (find matches)
Title: The half-tone process. A practical manual of photo-engraving in half-tone on zinc, copper, and brass
Year: 1904 (1900s)
Authors: Verfasser, Julius
Subjects: Photoengraving
Publisher: London, Iliffe & sons, limited
Contributing Library: Getty Research Institute
Digitizing Sponsor: Getty Research Institute

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:
Fig. 53. by means of a cam-shaped hook linking into a stapleat the side. McLaughlins frame (figs. 54 and 54A) is adistinctly novel one, as the front glass is hinged andthe filling is done the reverse way of the ordinaryframes, from the front instead of the back. Whatever form of frame is used, a thick felt padmust be placed between the metal plate and the woodenback. Rubber is sometimes used instead, but it isexpensive, and deteriorates very rapidly. When the exposure is made to electric arc light itcan be timed very accurately, but for daylight exposuresit is best to use an actinometer. The simplest form is THE PRINTING ROOM. Ill as %• 55- This consists of strips of paper so arrangedas to form steps, No. 10 being ten thicknesses of paper.This forms a mask behind which a piece of sensitivepaper is placed (ordinary P.O.P.) When a certainnumber (determined by experience) is visible on thesensitive paper, the plate will be fully exposed. For what is called the burning-in of the plate
Text Appearing After Image:
Fig. 54. after development, a good stove is required. Whilstany ordinary gas stove will do which has a powerful andwide-spreading flame, it may be pointed out that thereare now several stoves on the market specially con-structed for the purpose. Penrose and Co. have a stovewith three long straight burners (fig. 56) connectedtogether, enabling very even heating to be performed.Recently the same firm have introduced a stove whichcan be used for any photo-process. The iron plate onthe top is hinged so that the stove may either be used 112 THE HALF-TONK PROCESS. as a hot plate for line etching or photogravure, or thetop may be lifted up to permit of using the apparatusas an open stove for the dragons blood process, orfor burning in the enamel.

Note About Images