A manual of photo-engraving : containing practical instructions for producing photo-engraved plates in relief-line and half-tone with chapters on dry plate development and half-tone color work (1896)
Jenkins, H. (Harry), 1868- · Chicago : Inland Printer · leaf 90
sure as a pin-hole lens, and causes an image of the shape of theaperture to be formed upon the sensitive film.From this it appears that if we use a round aper-ture, the dots in the negative will be round, asquare aperture will produce square dots, a trian-gular aperture triangular dots, etc. It has… … LEVY DIAPHRAGMS. the whites in less time than round ones. Mr. Levyhas invented several forms of diaphragms, three ofwhich are shown here, the first form having a 58 MANUAL OF PHOTOENGRAVING. square aperture with two corners extended, thesecond having- the four corners extended, and thethird having-…
Photoengraving · Color photography
Internet Archive · Getty Research Institute · Public Domain Mark 1.0. Free to use for anything.
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