The application of digital proofing technology and the important role of software (4)

Printing and Ink Properties The profile file is the basic document for the three files and is the subject of digital proofing color being simulated. The profile files of foreign printing and ink pre-installed by the general color management software itself, if we use them directly, have been tested and the results are not good because the printing conditions and standards in various countries are inconsistent. We must have a profile that meets the domestic printability requirements. This is the most important aspect of the practicality of digital proofing.

With the print paper profile file and the printed profile file, the color gamut converted ICC Profile file can be generated on the color management platform; the color gamut converted ICC Profile file controls the printer color printing, and realizes the digital printing color gamut and the printed matter. The color gamut is the same. The generation of this document is the key to the quality of color reproduction. There are two important links here:

1 The digital proofing software can accomplish this step for the digital proofing RIP which can generally achieve the similar effect.

2 After the color space converted ICC Profile file, still need to use professional color management software and tools to further modify and edit the ICC Profile file, so that the color space parameters reach the target.
Spot color and PANTONE color simulations can be performed only after the above two links are completed, according to the spot color values ​​for strict spot color data entry and editing, but some are outside the spot color or gamut at the edge of the print color gamut. Spot colors can only be approximate, and some 8-color printers work better with spot colors. The combination of several sets of profile files of the above color management, we call the color management data integration, a high-quality data integration module is the core of color management of the digital proofing system.

According to the current conditions and status of digital proofing, color management data integration must be completed by a professional color management technology service company. The importance of the color management system is often overlooked, which is the bottleneck of accurate digital proofing color. Digital proofing color quality evaluation.

At present, the color target for color management is IT8.73. The 928 color blocks are used as color targets for color measurement. It basically covers commonly used colors for printing. The color reproduction degree of digital proofing is measured by its measurement parameters. There are three general physical indicators for color simulation.

First, the accuracy of color simulation, generally expressed as a percentage, that is, the color difference of 928 厶 h h h h h h h h h h h h h h h h h h Enh is less than 6 (En4r is less than 4) is calculated as a reduction basis, and should reach 95% or more;
Second, the average color difference 928Esh of 928 color blocks should be less than 3.5 (厶E., should be less than 2);
Third, the average color difference of the neutral gray balance and some memory colors should be less than 2 (厶E., should be less than 1); only the digital proofs that meet these three basic indexes can have better color simulation.

Fourth, digital proofing technology popularization and application of views:

With the continuous improvement and advancement of modern digital output devices, control software, and color management technologies, the advantages of digital proofing technology will become more and more obvious. The future of pre-impression proofing will inevitably be digitized, and its potential will gradually increase. Instead of completely replacing the traditional proofing: the continuous application and development of network technology, the development of digital proofing will also play a role in fueling the progress. The remote proofing and screen-to-screen soft proofing system is also being improved step by step. Digital proofing technology is a digital, scientific and standardized proofing method. Its products are produced under precise data calculation and instrument measurement control, which is different from traditional proofing based on the actual operation experience of workers. Its ICC color management model based on international standards will surely provide scientific and technical means for promoting the color standardization of production enterprises (such as the printing industry and the inkjet photo industry) with color reproduction as the main feature, and provide standardized management of product quality. Practical and effective technical data.

The popular equipment of digital proofing technology has its vast market and development potential in China. At present, while improving its print control capabilities, there is still room for improvement in maintaining consistency between digital proofs and printed matter. There are two main points:

1 Maintain the consistency between the digital proofing proofs and the actual printed matter. Due to the limitations of the existing digital proofing process and its RIP function, the unity of the digital proofing proofs and the final printed matter is maintained, the real simulation of the network points is solved, and the actual production capacity is improved by the digital proofing technology. To further develop the problem to be completely solved.

2 to meet the requirements of various printing special processes: to solve such as printing spot color, bronzing, hot silver can not be in the actual digital proofing equipment on the real simulation, and now to meet this process requirements also rely mainly on the traditional proofing, gravure, flexo industry There are still bottlenecks in the accuracy and material selection of existing popular equipment.
Although at first glance, the disadvantages and advantages of digital proofing are as obvious, but in general, its advantages are more than shortcomings and represent the future development trend.