Application of PDF in Prepress and E-books (I)

With the rapid development of digital technology in the printing field, traditional paper-printed books have begun to face severe challenges. At present, many large publishers and magazines at home and abroad, while publishing traditional books, simultaneously publish CDs with exactly the same contents. Many magazines even have an online version for readers with different needs. . Therefore, understanding the application of PDF in the prepress system can be said to be an urgent task for the present and the future. Below, we briefly describe the application of PDF in prepress and e-books:

The latest version of the current classic image processing software Photoshop, graphics processing software IIIustrotor, and groupware PageMaker, Indesign, etc. provide the function of converting files to PDF files. PDF, like Photoshop, was also developed by Adobe and is now the current open standard for electronic files worldwide. It has been introduced to the prepress industry for some time. Here's a look at how to apply PDF documents in the prepress area.

1, document generation

If you want to generate a PDF document, you can turn to the software Acrobat Distiller (literally "distiller"). Personally, I think that the use of "distillers" is more often used when generating PDF documents, and tools that generate PDF documents such as PDF-Writer are not used or even used. Of course, the best practice is to use the commonly used fonts by the author or designer, create a complete page in the application program, print it into a PS file, and finally use the “distiller” to “distill” the PS file to generate a PDF. Documentation. In addition, the use of Acrobat Distiller can also bring considerable convenience, for example: in the Distiller's settings dialog box, the user can pre-set the "distilled" "distilled" or externally input PDF documents for PDF Data storage and printing color separation.

2, document pre-check

This must be preceded by the use of special software tools to detect customer data transmitted through TSDN in network printing, and then the prepress can be processed on these data. Before processing PDF documents, it is necessary to detect the suitability of the document. . Of course, this kind of detection is very demanding, such as the integrity of the data in the file, the computer processing the document is missing a font and give a prompt, whether the document has a spot color and give a hint, the resolution of the gradient network in the document is consistent with printing Ask and give tips and more. This requirement can be satisfactorily solved with the PDF Preflight tool. There are many software vendors that provide software for solving such problems, such as PDF-Inspektor from Callas, Flight Check-pro from Markzware, Pitstop from Enfocus, and Inproduction from Adobe. If the detected data is all normal, then it can be prepressed.

3, color space conversion

The purpose of converting an image from one color space to another is to make the colors on the computer display and the final print as consistent as possible. However, each device has a different ability to represent colors, which means that the computer display screen and the printer have their own different color space, that is, the computer screen belongs to the color space of RGB, and the printing machine belongs to the color space of CMYK. How to make the color of the two reproduced as consistent as possible, we need to introduce color management functions. When the PDF document was detected, it was found out whether the document contained spot colors. In addition, PDF documents are used in the field of electronic publishing and are based on screen displays. Of course, they belong to the RGB color space. The CMYK color space is used in the printing field. This requires the application software to convert the RGB color space space to the CMYK color space without affecting the spot color effect. At present, this is not an excessive requirement because it can be solved with PDF tools. Adobe Inproduction provides us with the ability to use the ICC Profile when performing color space conversions. This profile determines the range of colors that can be reproduced by the output device. In this way, the relevant device property file data can be loaded when the color city space is converted, thereby achieving a more ideal color space conversion and reducing the color error caused by the different color space. In addition, Quite's software RGB-Gone, Quite's Quitea box of Tricks, and Adobe's Inproduction are all ideal tools for converting RGB color space into CMYK color space.

4, modify and edit

When it is found that there are individual errors in the PDF document, such as clerical errors, punctuation errors, etc., it can be easily modified by means of Acrobat. Because Acrobat's editing tool Touch up is designed specifically for modifying characters. However, the image modification and editing must be opened in Photoshop to modify the image processing. If you want to significantly modify the PDF document, such as the entire character block changes, color changes, changes in the location and line width changes, etc., then you must turn to PDF editing software. This type of software includes Enfocus's Pitshon. Of course, you can also open the PDF document in the IIIustrator 9.0, and then modify the document, and then output in PDF format. However, this feature was not available in previous versions of IIIustrator.


5, make a version

In the prepress area, the imposition of the version is always encountered. Adobe IIIustrator can make a multi-page PDF document into a large version. Of course, this is more complicated and will not be adopted unless it is absolutely necessary. Quite lmPosing provided by Quite works well if you want to use a PDF document to make a simple brochure or a few folds of promotional materials. If you need to do a lot of PDF document imposition, it is best to use Krause's KIM PDF software. Krause is located in Bielefeld, Germany's Ruhr industrial area. It is a company known for its CTP plate exposure machines. Its previous version of the KIM software was developed for use by the Postscript language. Now that the company is aware of the huge market for PDF, it has developed software that is based on the PDF language. The typical feature of the software is easy to learn and use. The user can perform a series of parameter settings in the preset dialog box, and then all the work will be completed automatically.