Print color management technology (below)

Third, digital proofing

After several years of development, the output performance of the digital proofing system, the color management system for digital proofing, and RIP have all been significantly improved. Especially in the past two years, the digital proofing system has gradually gained recognition in the industry after technological advancement and continuous breakthrough in performance. This should be the beginning of the popularization of digital proofing technology in China's prepress industry. At the same time, the development of new technologies and new equipment has accelerated the wide application of CTP and accelerated the development of digital proofing. Digital proofing is the key link between prepress and printing, and it is also the only way for future printing technology development. At the same time, with the rapid development of the Internet and people’s constant pursuit of efficiency, remote digital proofing technology has begun to attract people’s attention. Remote proofing, as a new proofing method for the rise of the Internet era, will be widely used in more fields. application.

At present, the number of domestic digital proofing software is also more, mainly in the following categories:

1. GMG

In October 2003, GMG, another German software company, started its operations in China, bringing high-end color management process solutions to the domestic proofing market. There are three types of digital proofing products: GMG ColorProof, GMG DotProof, and GMG FlexoProof. It is reported that GMG ColorProof software has achieved outstanding results in international proof contests for many times (such as the second IPA color proofing system in Chicago in June 2004 and the fourth digital in Stuttgart, Germany in September 2004. Proof contest. And the author also found in the course of using it has many other software unmatched advantages, especially in the single black, spot color and true dot proofing is even more excellent performance, more gratifying is that the company is conducive to its closed-loop Calibration technology forms a color-corrected closed-loop system, providing users with a remote proofing solution with consistent color proofing and a very high price/performance ratio.

2. Best ScreenProof

In the field of commercial printing, the most widely used is the EFI Bes ScreenProof. Since 1999, the German Best Company (acquired by EFI) has launched the Best Color digital proofing system based on ICC color management technology. With the performance of digital proofs with good output quality, the performance of the digital proofing system seems to have been completely changed. Due to the early entry of the software into the domestic market, many users now use the software, but the software is based on the ICC color management system. Due to the shortcomings of the ICC technology, the user inevitably encounters some problems during use. For example, when the RIP is linked to a network, the network angle is hung at 45 degrees or the number of network lines is wrong. Using the software for proofing cannot be identified, and it may result in great losses. There are also problems such as single black, four-color black, and gray balance that have not been well improved. Therefore, it is up to the developer to improve it.

3. BlackMagic

This piece of software from Australia is now represented by Gao Technology. It only controls the spot color when dealing with spot colors, the effect of selective color correction function is not ideal, the control of the level curve is not very accurate, and needs improvement.

4. Express Color RIP

The color management software is Jinhao's digital proofing system, the hardware is mainly integrated in HP inkjet large format printers, such as HP DesignJet 5000 large format printers. The Express Color software is based on HARLEQUIN's Postscript Language Level 3 interpreter and is developed using the powerful Harlquin ICC Profile Process color management combined with 2-bit precision screening technology.

Fourth, need to consider the issue of color management

With the constant updating of various technologies, the methods of color management are also constantly improving. If we strictly judge the methods used in these color management and the final results achieved, I believe that the following aspects should be discussed:

1, the input of the file color and level control

Already, fewer and fewer people are able to master the key points of image input (such as the control of the calibration of highlights and shadows, etc.). Therefore, high-end digital cameras cannot be fully applied in the printing field. Flat-panel scanners have also been serving as supporting roles under discontinued electric extensions.

2. Processing of images after obtaining image information

How to unify the color space from different places and getting the image information by different input methods, that is, the standardization of the image. How to do a good image color removal and control of the proportion of sharpness. These problems are often overlooked, and as a result, the color of the image is not fundamentally managed. Pay attention to this when performing color management.

3, the problem of color change after the file is processed by different software

The files are processed in different software or the same software is different - the version - the final image output processed by the present are all different, we have to solve the unified problem of the color space in order to achieve different pages, different file color space Unite.

4、In the early printing stage, the mutual color management is combined with printing

Most of the existing color adjustments are performed during the printing process for proofing and printing, and the relative color is unified by relying on the printer's larger color adjustment range. However, in actual production, it is not always possible to meet the user's requirements each time. If the color space of the image differs greatly or the capability of the printing press cannot meet actual requirements, there are multiple printing machines to be printed at the same time. In the case of a printed product, the color of the printed matter cannot be guaranteed. If we want to realize the standardization and standardization of the process, it may be a new idea and a more effective method to perform color management on the printing press before PS-version.

5. Accuracy, consistency and stability of digital proofing and prints

For now, the effect of digital proofing is still far from adequate when it comes to solving the problem of color in the entire printing process. Although it has been popularized for many years and many companies are using it, how many companies actually use it or they are It is how much it brings to production, perhaps only the company itself knows best. In fact, there are still many things worthy of discussion on the digital proofing system alone, such as: the consistency of proofing color and printed matter, the color difference of color, the treatment of gray balance, black-printing, the processing of spot colors, and proofing The stability of the system itself, the unity of the two printers of the same type, and the true security of the dot proofing.

6, proofs and print inspection methods

To finish the color management of the printing process well, a high-quality color management system with powerful automatic functions is required to serve the entire process. After we have completed the color management, we will eventually use the inspection system to verify the consistency of color, but it must also be established on the premise of accuracy, safety, convenience, and speed.

To sum up, we need a series of color management systems that run through the entire printing process to solve the problems encountered in these productions. It must be convenient, automatic, fast, process, and accurate to solve the problems. The meaning of existence! Color management from RGB files - Color management of CMYK files - Color proofing - Color management of printing presses - Optimized management of printing inks - Dot proofing after RIP - Proofing and detection of printed colors. I believe that if a printing company has these systems, it can not only solve the problems of color for many years, but also can improve the technological level under the precondition of stabilizing the production process, solve production problems for enterprises, increase production efficiency and reduce production costs. It will also enhance the market competitiveness of enterprises and be able to continuously meet new challenges.

Source: China Printing Card Card