Oki ES3640eMFP, Справочное руководство

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ES3640e MFP Color Reference Guide - 97
Printing techniques
Until recently, most color printing was done on printing presses
using one of several printing techniques—
offset lithography ,
flexography , or gravure , to name a few. All traditional printing
techniques require lengthy preparation before a press run can
take place. Short-run color printing, including Fiery printing,
eliminates most of this preparation. By streamlining the process of
color printing, the Fiery makes short print runs economically
feasible.
In contemporary offset lithographic printing, digital files from
desktop computers are output to an
imagesetter , which creates
film separations. The film is used to make a prepress proof , which
is an accurate predictor of the final print job and allows you to
make corrections before going to press. Once the proof is
approved, the printer makes plates from the film and runs the
print job on the press.
With the Fiery, you simply print the file. The Fiery processes the
PostScript information in the file and sends four bitmaps (one
each for cyan, magenta, yellow, and black) to the printer. The
ease of Fiery printing makes possible experimentation that would
be too costly on a press, allowing unlimited fine-tuning of color
and design elements.
Halftone and continuous tone devices
Halftoning is used in offset printing to print each process color at a
different intensity, allowing millions of different colors to be
reproduced using only the four process colors. Depending on the
required intensity of a given color, toner is placed on paper in dots
of different size. The grid of dots used for each toner color is
called a screen. Halftone screens are aligned to unique angles
designed to eliminate interference patterns called
moiré that can
arise with halftoning.