Horgan's half-tone and photomechanical processes .. . s way: After placing the plateholder containing the sensi-tive plate in the camera, draw the slide so as to uncover forexposure one-third of the sensitive plate; this we will callexposure A. Then by drawing the slide again expose two-thirds of the plate for exposure B, and finally expose the fullplate for exposure C. Before making exposure A, the shadow stop has beeninserted in the lens; then remove the cap from the lens forfour minutes. For exposure B the normal stop is inserted inthe lens and the cap is withdrawn for two minutes. Forexpos
Horgan's half-tone and photomechanical processes .. . s way: After placing the plateholder containing the sensi-tive plate in the camera, draw the slide so as to uncover forexposure one-third of the sensitive plate; this we will callexposure A. Then by drawing the slide again expose two-thirds of the plate for exposure B, and finally expose the fullplate for exposure C. Before making exposure A, the shadow stop has beeninserted in the lens; then remove the cap from the lens forfour minutes. For exposure B the normal stop is inserted inthe lens and the cap is withdrawn for two minutes. Forexposure C the high-light stop is inserted in the lens and thelatter uncapped for one-half minute. Development of this plate will exhibit on section C theeffect of the high-light stop alone; section B will show theeffect of the high-light stop and the normal stop; and sectionA will demonstrate the result of the exposures of all threestops. To study properly the effect of these trial exposuresthe negative, after fixing in cyanid of potassium, should first. A HIGH-LIGHT HALF-TONE OF S. H. Horgan. THE HALF-TONE PROCESS 95 be intensified with copper and silver as explained in thechapter on line negative-making. After intensification, if the shadow dots are not intenseenough in section A, the checker-board pattern not strongenough in the middle tones of section B, or even in section A,and should the high lights not show a tendency to close upin section C and be almost entirely closed in section A, thenthe exposures on all three stops have not been long one or two of the exposures be sufficient, this trialnegative will show it. If on the other hand the exposuresseem to have been carried too far, then try the effect ofcutting the negative as will be explained later. KEEP A RECORD OF EXPOSURES. Just here the reader is recommended to keep a record ofeach negative with all the factors that entered into themaking of it. There are exposure books for dry-plate pho-tographer
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