to Desktop publishing houses (English DTP from "Desktop publishing") name use of the personal computer for a writing, illustrations and impositions of documents which then can be printed with very high quality.
By means of desktop publishing system it is possible to create the document of any complexity, from simple black-and-white leaflets to polnotsvetnyh magazines and books. From the end of 1980th desktop publishing systems have gradually started to supersede traditional methods of preparation of the printed matter, based on a division of labour between separate experts and the whole firms. One person sitting at the desktop personal computer, has had an opportunity to carry out set of operations - a writing and text editing, prototyping and imposition of pages, document preparation for printing and tsvetodelenie.
The Desktop publishing house has appeared in the mid-eighties thanks to four breaks in computer technologies. Creation of personal computer Apple Macintosh with the graphic interface became the first - and the main thing from them - allowing to see on the screen of the monitor a font and the image how they will appear on a paper, and to use "ь№°ъющ" to choose a symbol on the screen by means of an arrow-cursor and to enter a corresponding command.
The inexpensive laser printer Apple LaserWriter providing the press of the text and schedules with the high permission was the Second achievement. The third - creation by company Adobe Systems of language PostScript which has allowed to send from the computer on the printer very exact description of a kind of unpacked page. And, at last, computer imposition of documents became the fourth achievement. Expression "эрё=юыіэюх шчфр=хыіё=тю" the head of firm Aldus Corporation and one of developers of software package PageMaker has entered into Pol Brejnerd reference. For the first time having appeared in October, 1985, PageMaker has united in itself technologies Apple and PostScript, becoming inexpensive system for operative creation of high-quality breadboard models. It is interesting that company Aldus has been named in honour of Alda Manutsija (1450-1515), the Venetian printer who laid the foundation for many parties of typographical business and has created the most beautiful roman types. In 460 years after his death one of the best Soviet schedules-shriftovikov Vadim Vladimirovich Lazursky has written the book which has become by a rare book right after of issue about Alde Manutsii and its associates... The Complete set of programs for desktop publishing house usually includes the text editor, programs for processing of a raster (dot) and vector (linear) drawing, and also the imposition program. Very often in desktop publishing houses the scanner is used, allowing to digitize printing images for the subsequent gluing in in a breadboard model.
The Scanner is a device, reformative colour and brightness of each point of the image in a digital code which then registers in a file. The principle of action of the scanner is based on transformation of light energy to the electric. The ray of light falls on the scanned image, is reflected from it and comes back back in the scanner. There it gets on a ruler of photosensitive devices with charging communication (PZS). Depending on quantity of light getting on PZS, the current proceeding through it changes. The high-sensitivity measuring device defines changes and will transform them on brightness degree to numbers. Proceeding from each number degree of blackout of separate pixel (English "picture elements" also is defined; means "Іыхьхэ=№ шчюсЁрцхэш ") - a tiny point, an image component on the computer monitor.
The digital image Received as a result name raster. After numbering the image can be changed by means of programs for processing of facsimiles. These programs have a set of special tools and filters for editing of photos: stains and scratches can be completely removed, the image background - is changed, and even all colour scale can be corrected. Programs for processing of facsimiles are used and for creation of illustrations from zero. The software package for drawing allows to operate geometrical konstruktivami (lines, pouring and curves), instead of raster images. The digitized and processed image can then to be imported to a breadboard model of page by means of the imposition program.
Exists three basic programs of imposition: Corel Ventura Publisher, QuarkXPress and already mentioned above Adobe PageMaker/Indesing. By means of one of these programs verstalshchik according to design requirements unites in the uniform document files of various types. The imposition program allows to set quantity and the sizes of pages, to define a kind of elements of page, to carry out typing and to establish a text arrangement on page, and also a relative positioning of the text and illustrations.
the Symbol and a font
The Shape of the text in the document is defined by fonts. A font name a character set (including figures and punctuation signs), soglasujushchihsja with each other on a tracing and the sizes. The font can be a component of the program of imposition, or he can be bought as additional software product and if necessary podgruzhat in the imposition program. Alternatively are available also the font cartridges executed in the form of replaceable blocks to laser printers and containing additional fonts, written down in their ROM. Thousand computer fonts are created shriftodizajnerskimi by the firms earlier making casting of letters for the press from metal type-setting forms.
So, at page scanning each point is distinguished and marked as black, white or colour therefore raster images turn out. Transformation computer, i.e. Vector, images in the raster makes so-called raster image-processor (RIP), using a raster grid. On an input of the raster processor the set of commands in PostScript, language of the description of pages for the printers, developed by firm Adobe Systems in the mid-eighties arrives. Images in language PostScript, for example, the pictures created by means of programs for drawing, comprise instructions for vyvodnogo PostScript-devices together with raster images for their reproduction on the computer screen. Raster images help verstalshchiku to receive representation how the imposed page with an illustration will look in the unpacked kind.
The publications Prepared for duplicating can be unpacked on a various output equipment, depending on an expected end result and demanded quantity of prints. In particular, for this purpose monochrome laser printers are widely used.
By a principle of action they are similar to photocopiers: at the heart of it lies elektrizatsija a laser beam of a surface of a special selenic drum. To the electrified sites of a surface of the drum, corresponding to the image, sticks poroshkoobraznyj a toner which then is transferred thermal way on a paper surface. Resolution of modern laser printers makes from 600 to 2400 dpi (English "dots per inch" means "=юёхъ on inch).
Polnotsvetnaja the press is realised by means of the several technologies providing different quality and cost of prints. Colour laser printers allow to receive the most inexpensive copies, however listings look more rough, since. Paints quickly fade. Besides the printers using a principle of thermocarrying over, work very slowly as the pause after pass of each of four (on number base colours) printing heads is required to them - after all wax should cool down.
Jet printers put on a paper the image by means of the smallest drops of liquid ink. The quality of the image received on "ё=Ёѕщэшър§" with use of a special paper of high density, can be excellent, but the print turns out very expensive.
The highest quality from all "эрё=юыіэ№§" technologies of the press provides termosublimatsionnyj a principle. Received on termosublimatsionnyh listing printers are very similar to photos. Colour points of which the printed image consists, in this case are put on a paper by sublimation (transition from a gaseous phase in firm) the evaporated dye. Thermosublimation provides very exact transfer of shades and semitones, rich colours, and the print surface becomes glossy. A unique lack of technology - print cost still above, than at jet printers.
In modern publishing jet and termosublimatsionnye printers are used for a conclusion of a small amount of very qualitative prints - for example, photos. If it is necessary to print some tens or hundreds copies of the document, it is used laser printers. And at last, at great volumes of the press are used the typographical offset printing which quality can be the highest. To prepare the document for offset printing, processes tsvetodelenija and a photoconclusion are used.
All printing processes include certain base stages of preparation of the document and illustrations for printing. In "фюъюьяі¦=хЁэ№х" times preparation for printing consisted in manual typing from the separate metal letters engraved or cast. Type-setters had their letter behind the letter, typing lines or text pages. Bukvo and strokootlivnoj the set dominated in polygraphic business up to 19b0 th years then it was completely superseded by phototypesetting.
Result of phototypesetting is the image of pages of the document on a special photosensitive film. By means of photoetching process these prints are transferred to printing houses in the form of a relief on special metal plates which then are established in a press.
As well as in colour printers, at polnotsvetnoj offset printing use four paints - on number of base colours CMYK (blue, purple, yellow and black). Accordingly, before phototypesetting the image of the document shares on four colour components - is carried out tsvetodelenie. Then in the course of phototypesetting for each colour the separate film is deduced. And on it the separate plate of offset printing is etched.
With universal distribution of personal computers the new kind of desktop publishing - preparation of electronic publications was born. These are documents which are intended mainly for viewing on the screen of the computer monitor, instead of for listing. Such electronic documents - for example, digital encyclopaedias - often extend on computer disks of CD-ROM or in a network the Internet.
More often electronic publications are created in the usual program for imposition, and then by means of package Adobe Acrobat will be transformed to format PDF (Portable Document Format). This format is supported by almost all computer platforms - from Windows and Macintosh to UNIX and Linux...
To the middle of 1990th years desktop publishing systems began to use for creation of Web-pages. However specificity of hypertext format HTML used in Web-documents (Hypertext Markup Language) does not allow to use effectively the traditional programs of imposition focused on a paper. For HTML-imposition specialised Web-editors is better approach.
Modern computer technologies create grandiose possibilities. Many publishers of reference books, for example, pass to compact discs or the publication Internet-. It is no wonder - after all it is possible to edit and supplement them with a new material much easier and more cheaply! Already there is a concept "Іыхъ=Ёюээр ъэшур" and many say that the paper literature leaves in the past...