JF Ptak Science Books LLC Post 558
The history of illustration has some distinct phases: from woodcut to wood engraving to engravings on metal to lithography to printing in colors to chromolithography...and then on to a process that would begin to do away with all of those processes, the half-tone. This was a process whose foundation was laid in the 1850's by William Fox Talbot and brought to life in 1873 by Stephen Henry Horgan, though it really wasn't commercially viable until Frederick Ives further deepened the process in 1881, finally becoming a staple in the printing industry in the mid 1890's. The half-tone process would basically due away with the line-centric engraving process, as it was much quicker and easier to use, making images much more readily available to daily-printed media like newspapers. Images that were drawn could be rendered without being engraved; also, one of its greatest advantages was being able to reproduce photographs, which was an enormous breakthrough, as a photograph automatically increased the veracity of the image. (During the U.S. Civil War, reader's of the illustrated
weekly journal Harper's Weekly trusted battlefield images more if the wood engraving appearing in the magazine was copied from a photograph rather than being from the sketchbook of the
correspondent on the scene. The photograph would capture a particular point in time (nearly) instantaneously, whereas the war correspondent artist captured bits and pieces of an instant flavored with memory and subsequent action. The phrase in the credit line. "Drawn from a photograph", had real value.)
And so it came to pass that the happy lives of dots and lines--so important and intertwined in such things as the Morse Code--made a particular and dramatic break with the triumph of the half-tone over the engraving in illustrating popular publications (from the 1890's to the 1980's).
The image above at left is a magnification of an engraving from 1760;above right is a half-tone image of a 1905 Alfred Stieglitz photo; below left is a magnified sample of what the Stieglitz was composed of; and bottom right finds an illustration of the different combinations in size and color that would effect the composed final image in the final column.