In the DRUPA 2000 conference, many manufacturers are talking about the terms CMS, PDF and CIP3. Many people are quite aware of what it is all about. There are also quite a few people who are simply taking a pet phrase and have not carefully studied the implications of these three words.

In fact, in the future, regardless of the Internet or other transmission methods, for the printing industry, remote proofing, Intranet, CMS color management, PDF file, and CIP3 common information management will all be very important file management models. And file specification model.

I. CMS color management

The CMS (Color Management System) color management system is a color reproduction management mode existing in the era of closed scanning color separation machines and CEPS high-order computer group pages. Its principle is to convert the light and darkness of the manuscript to color The machine's CMYK dot readings, and then use these CMYK dot readings to record, output into a net, after the printing, proofing, fight group small version, large version, large version, on-machine printing, etc., after many complicated work links Only satisfactory color management and reproduction can be achieved. At the time, the Cscan included Crosfield in the UK, Lino Color from Hell in Germany, SG color management from Dainippon Screen, and later the Scitex Smart Scan color management from Israel. Technical support.

Today, everyone has abandoned the use of expensive CEPS systems and drum type electronic scanning color separation machines, and instead use DTP built on an open system architecture. Because it is an open architecture, DTP loses the original high-order scanning system or scanner original factory rigorous regulation specifications and hardware resistance adjustment degrees in the color management; and the original 10 bit, 12 bit color performance levels, Also because of the software relationship, we all changed to 8-bit colored and various levels. Even if you just go to the street and spend hundreds or even thousands of dollars or tens of thousands of dollars, you can buy a flat-bed scanner with its own driver and color trapping and adjustment software. Some of the scanned images are in RGB format. In the world of DTP is so chaotic, it can be said that each person speaks different words and plays different tune. No one can set up this important CMS color management work for you.

In this case, major film companies such as Kodak, Fujifilm, Agfa, software companies such as Adobe, and color separation machine manufacturers, etc., formed an alliance. After many studies and consultations, all parties could Within the accepted color gamut, IT-8 color reproduction specifications were made, including both input IT-8 and output IT-8, and then in this IT-8 color gamut, each company reduced its color range again. To match this standard. The range of color gamut and concentration values ​​have been greatly reduced, becoming the core tools and conditions of CMS used today.

The most successful of these is the CMS for inputting tools and conditions, including IT8 7/1 Transmittal 4x5, Transmissive 120 and 135 manuscripts, and IT-8 7/2, which also provides reflective draft input correction, that is, each film manufacturer. After the production of the IT-8 control chip is completed, the laboratory will make a copy of the value of the file, so after the user set the input tool hardware and software, do a trial scan data, but there will be a considerable degree of difference, so Must be displayed on the screen, and then the image is transformed, set in the original file information on the computer to do analogy, these 264 grid input IT-8 will be compared to generate Profile correction file, then the future encounter this color or similar color , The correction file will automatically do compensation work, so that the color reproduction is in line with the original factory specified ideal value.

Therefore, using IT-8 as an input tool, screen color reproduction, various printing, and printout, all must use computers and files for analogy, and then generate correction files to provide adjustments for copying or display color reproduction so that the copying and display effects are close to " Ideal "the point.

This design is indeed very convenient according to the process, and has good practicality. However, as mentioned above, the CMS system is a color gamut specification that is completed under compromise, and the innate conditions are insufficient, so its color reproduction capability is limited. Just like an iron bar bends, it is difficult to restore it to its original shape.

In addition, when going from CMYK to RGB file, the CMYK file has directional conditions. The lithographic, letterpress, flexo, gravure, screen, ink jet, and digital printing each have different reproduction ranges and can only be used alternatively. The length is specified in Zhang Yeping India. Different printers, papers, and inks also have different reproducibility. Even if a machine's cold machine and warming machine have different color reproductions, CMS has many problems besides converting the ICC color space problem. . There is a problem that exists extensively in the operator's inconceivable mistakes, that is, each IT-8 factory has factory settings, not every IT-8 file value can be applied to all IT-8 manuscripts If there is no right number, then there will be a big gap between the results.
In addition, IT-8 will change its fading color after a long time. If CMS replication is used as a standard tool, I am afraid there will be very bad results. Therefore, IT-8's original file is used correctly for analogy and IT-8. The storage of color samples is an important condition for CMS.

The CMS of the screen is theoretically feasible, but there are two completely unsolved problems. One is that the fluorescent screen is displayed in RGB format using the additive method. The gamut space and print or proof print are reduced. CMYK is not the same; the second problem is even more serious, which is based on the human eye to determine the screen color, it involves the background brightness, color and color psychology issues, the external brightness and brightness of the image density greatly different interpretation gap, the more Bright, the eyes feel that the screen color is too dark and too turbid, and vice versa; the other point, the brighter the screen will produce paint reflections in the dark, reducing the image contrast is very serious, so in the same brightness background, the visually adequate personnel Training and adjusting are more important than adjusting the CMS theoretically.

As for the CMS on the output side, it is not really a very clear system. It cannot change the limitations of various existing output devices. It can only improve the mechanical adjustment conditions and material usage, and then according to this acceptable high standard, it is required to output the print reproduction. The scope of choice adjustment. This kind of situation is just like the tutor of a student in a higher education class. In the face of students with different qualifications, learning abilities and attitudes, they can be tutored to participate in the separate recruitment exams of the schools. In the face of an ordinary student who is qualified but works hard, you want him to go first-class. It is impossible for a school to have students who have good qualifications and ability to study. It is unfair to ask him to apply for admission as long as the middle grades are acceptable. The teacher is like a CMS, and the adjustment of the output is mostly test and adaptation. It is necessary to change. Extremely limited.

We are not happy to see many people refer to CMS as a panacea and think that if it is available, it can be done. In fact, it is only a formulating tool.

Second, PDF portable file format development

Adobe company in the United States is the world's second largest software company. There are many video, layout and drawing software sales. More importantly, the Post script Level II page description language developed by Adobe is publicized at the request of many manufacturers. By free use by everyone, it has become the world standard for publishing and printing industry, thus laying the foundation for Adobe's leading position in this area.

Recently, Adobe has developed a PDF file (Portable document Format), which is a file format with almost no restrictions. It can be displayed and executed on any platform, regardless of whether it is a font or not. The media went to electronic media. This is an extremely convenient file format for the printing industry. Because in Taiwanese design companies and export centers, the use of Macintosh computers and the Windows environment has become quite popular. File interoperability between the two platforms has also become very important, especially fonts. In part, this is not allowed in Postscript files, and it is unobstructed in PDF file format.

Another advantage of using PDF is the file size compression. It increases the convenience of file storage and transmission. The more important point is that the PDF file is called “electronic negative film”. This is a file format that does not have different interpretation devices or platforms. The appearance of garbled characters or different results is not only of importance to the printing industry that uses decentralized processing, but also makes it possible to use Post Script LII to solve the problem that CTP output errors cannot be corrected. Because the RIP and CTP RIP conditions used for digital proofing are different, the output may produce discrepancies. This is extremely taboo on print jobs. The use of PDF files can eliminate this crisis. Another example is carton packaging, trademarks often reprint, after the first CTP publication and printing, reprinted after three or five years, if you use Post Scripf LII files, due to time and space transfer of different platforms, versions, fonts and interpretation Under the condition of the device, it is easy to generate garbled characters, missing pictures, and missed words. It is a very serious problem for the printing industry to make mistakes in reprinting. According to the author's opinion, if there are prints that need to be reprinted, they must use the CTP direct plate output. The PDF file is also very worthy of choice in the workflow.

Many people mistakenly believe that the PDF file is a page file format eagerly promoted by the printing and publishing industries. In fact, the military is actively promoting the use of PDF files because when the military establishes a computer system, not only each service is independent, but also the same service. Weapon systems also use different computer platforms. So today, when the three armed forces are to jointly fight, all computers will say the same things as chickens and ducks. Each tune is different. Do you say this? So using a PDF file without a platform to limit file formats across various conditions may be a solution to this dilemma. In many cases, it would be ideal to use PDF native code to create pages, but so far it seems to be still not popular, so Adobe launched In Desgin three-in-one software, the image, drawing and editing (Photoshop, Illustrator, Pagemaker) three The operating software is brought together and fully supports the PDF format. I believe that the In Desgin software will soon be more convenient to use.

Third, the prospects of CIP 3

CIP 3 stands for Computer Intergrat Prepress, Printing Press, and Post Press. Because the last word of each workflow starts with P, CIP 3 is formed.

At present, because of the development of new technologies, an additional P, so it was also known as CIP 4, is a non-profit organization composed of Agfa, Adobe, Heidelberg, Manroland, KBA, Komori, Polar, Sfahil, MBO and other companies. Co-developed, mainly focusing on the prepress Prepress, Printing Printing Press, Postpress and other projects, so that front-end work generated by the management, instructions, imprint, specifications, contacts and other information files, can be successfully transmitted from The next project makes the work easier and smoother, and it is especially important that companies use the same file format. This does not create a gap due to the closed system. As a result, they used the Post Scrirt Level II file format in the early days to adapt to the majority of prepress page descriptions, and they have also reached consensus on the common adoption of PDF files.

The JDF file describing the content of CIP4 contains the following information: customer, file name, print size, color number, number of copies, number of prints, processing instructions, cutting, origami, binding planning, use of materials, thickness, rough printing, Ink Pro All colors are assigned with the ink key pattern distribution percentage, job message instructions, etc.; future work processes, progress tracking, material consumption hours, accounting records, cost accounts, etc. will all be added. Therefore, the traditional paper summons can now be delivered to every worker's hands as long as they are electronically transmitted through the Internet.

Among these pieces of information, the Ink Pro printing profile is most useful because it can be used to further adjust the size and thickness of the press, and also to open or increase the number of ink fountain buttons. Eliminating the time-consuming task of requiring masters to tune the ink tank, and converting it to ink with a more accurate and reliable imprint distribution information file.