Топик По Английскому Языку (Воронов Р. И.) / Prepress

Prepress.
A number of printing processes are used to produce the many different types of printed products. Each printing
process has three main operations, or steps: prepress;press;and post press. The prepress step involves the
preparation of the copy or information for printing. Before the introduction of electronics and computers in
printing, much of prepress operations were manual. Digital imaging with computers and software has almost
completely replaced all manual operations, but prepress still is similar for all printing processes. Printing
is the reproduction in quantity of words and pictures on a page or document. Prepress is the series of
operations involved in the preparation and assembly of all copy elements ready for printing on a printing press
or digital printer. Type has a number of different characteristics and styles which are divided into numerous
classification. Typefaces are usually available in 6-to 72-point, with a complete font in each size. Capital
letters are called uppercase and small letters, lower case. In lower case letters, the upper stroke ("b") is
called ascender, and the downward stroke ("g") is known as descender. The short crossline at the end of the
main stroke is called serif.Typefaces without serif are called sans serif. The body or x-height makes up the
greatest portion of a letter. Befor digital typesetting there were three basic mathods of producting type:
1)case metal or hot type composition which refers to cast metal type set by hand or mechine; 2)typewriten or
strike-on composition (cold type); 3)photographic and electronic typesetting; The type specifications should
be clearly and completely written on the typed manuscript with the size, leading, typeface and measure in that
order. Art preparation embraces all of the steps in getting the art and copy ready for reproduction. There are
two basic steps: 1)the desigh or iayout of a printed piece, and 2) the preparation and assembly of the verious
components for reproduction, either manually or electronically. Almost all copy preparation are now performed
with desktop publishing components such as personal computers using application software, desktop scanners and
printers.Imaging is the most important step in the hierarchy of prepress operations. It is the operation in
which images for reproduction are collected, created and/or corrected prior to assembly for platemaking.
Since 1990, many photographic operations and supplies have been replaced by digital imaging systems. Knowledge
of the principles of light and color is critical to the proper use of all visual processes including photography,
printing and digital systems. When an additive primary color is subtracted from which light, the two remaining
colors form a new color. When red is substrated from white light the new color is clled cyan(c). When green is
subtracted is called magenta(m). When blue is subtracted is called by yellow (y). These are called subtractive
primary colors which are addreviated as CMY. The additive primaries (RGB) are the colors used in imging, as
the colors of the filters used for color separation. CMY with black (k) is called CMYK.
Digital typrsetting started as photomechanical typesetting in 1949non a converted line casting machine. It was
followed by electromechanical typesetting in 1954, the electronic typesetting in the 1970s. It became the plain
paper digitaltypesetter in 1985, that developed into the imagesetter in 1988. The scanners is one of the most
important elements in digital and color electronic publishing technology. Without it, there has been no way
to capture and input analog pictures and art. The first commercial electronic scanner was introduced in 1950.
The desktop computer was adapted to the printing in-dustry as early as 1982 when the IBM personal computer
was programmed to run crude typesetting and pagination programs.igital imaging has opened new vistas for
platemaking. Instead of being dependent on the prepress operations of film making and assembly, image carriers
can now be made directly from digital data without the needs for films and their assembly into plate layouts.
Each printing process uses a different kind of image carrier which relates to the characteristics of the image
to be produced, the type of ink, and press used, and the number and speed of impressions to be printed.