Color management in proofing field (middle)

Editor's note: The successful implementation of color management not only requires printing companies to introduce advanced tools, but also requires users to have the ability to use and manage these companies.

Contract proofing requirements

Although printing customers can choose from a variety of proofs, the focus of this article is on contract proofing-this is very important for both print buyers and printers. Since this proof can play the role of a contract, it also has very strict requirements for color management. Let's take a look at the specific color management requirements of this proofing system.

Color accuracy and repeatability: These concepts are often confusing. Accuracy refers to how close a particular proof is to the ideal color. Think about the speedometer in your car! If it is accurate, then when it shows that your speed has reached 90 mph, you may be really overspeeding.

Repeatability measures the stability or consistency of something over a certain period of time. Of these two factors, repeatability is more important than accuracy. If the proofing system can not accurately print the color you want, but it can always produce the same effect, then you will gradually get used to it, and even predict what the proofing will look like. However, if the effect of proofing cannot be repeated, or it cannot be kept consistent, then its accuracy will not be discussed.

Our analysis of cars shows the importance of repeatability. Maybe you know that your speedometer is inaccurate, but it can be repeated. For example, when it displays a speed of 45 mph, you know that your actual speed has reached 55 mph. If it is like this every day, then when you drive your car on the highway, as long as the speed displayed on the speedometer does not exceed 45 mph, you will not be issued a ticket. However, if the performance of the speedometer is not stable enough, when it displays a speed of 45 mph the next day, your actual speed may have exceeded 65 mph.

Proofing requires both accuracy and repeatability. The accuracy of proofing is still a hot topic in the industry today. As you can see at IPA and other industry exhibitions, well-made proofing systems generally have high accuracy. Some equipment manufacturers even claim that their proofing tolerance is within 2 Delta E. Nevertheless, when you evaluate the repeatability of a system and try to integrate it with multiple systems, since each system has certain errors, the accuracy of the proofing becomes very important. Imagine if there are ten proofing systems in ten places, and each system has an error of 2 Delta E, then how big the error will be when added together!

Verification Standards: It is very important for print production to make each of the same sheets meet certain specific standards. Although this concept is relatively unfamiliar to many people, it is the most basic quality control method for every print production. Taking a car as an example, a driving license is a radar gun in the hands of a policeman. It determines whether your performance meets the requirements of relevant standards. It may be difficult for customers and printing houses to determine which standard they should choose, but verification procedures are indispensable in any production process.

Matching of local and remote proofing and proofing in various places: In a proofing environment with multiple decentralized systems, the proofing location must remain stable. With the upgrade of prepress systems, the popularization of broadband networks and the emergence of globalization, remote proofing systems have become a magic weapon for printing companies to maintain a competitive advantage.

With the strong support of software, hardware and technical services, content providers can modify and confirm the final printed content and color proofs locally through a remote proofing system without having to go to the printing house in person. This process is very fast. Not only can it save on express delivery costs, but it also allows print buyers to modify the contents of the document at the last minute before payment. In today's market, it has become quite common for printing customers, advertising agencies, and printing service providers to cooperate in different places.

In this case, there are more important factors than accuracy and repeatability that we have to consider.

Setting up a local proofing system is relatively easy. You can define your own color standards and print test charts to see if it meets the standards you have set. However, if you want to extend this form to multiple systems-side by side or all over the world-then its cost and complexity can be greatly increased.

We can consider the simplest case. Under normal circumstances, the operators of remote systems have not received formal color management training, and they do not know what it means to make changes to the environment. Some people may say, "Wow, this screen proof looks much better than before, because I adjusted the brightness and contrast of the monitor."

If you are using a remote color proofing solution based on a monitor, it will have very strict requirements on the surrounding environment and hardware, especially to control the settings of the monitor to create an ideal soft proofing environment. Because of this, screen proofing is currently used more in the stage of typesetting and content correction. It allows printing houses to send draft proofs to customers in the early stages of production, so they will not let customers know what the printed matter will look like before making a plate.

Hard copy remote color proofing also places high demands on the environment and tools. For example, the lack of color separation calibration and characterization description files can make remote proofing more complicated. To obtain high-quality contract proofing on multiple remote ICC proofing systems, the characterization description files of each proofing machine must be optimized, and sometimes even require manual adjustment by the operator. This model itself is prone to errors, consumes a lot of labor, and is difficult to manage. Fortunately, we have now found a solution that can replace it.

User environment and tips: When the proofing system is limited to the internal use of the printing house, things become relatively simple. Good printing houses generally have technicians with color knowledge, and the distance between the proofer and the printing machine is relatively close. Now, with the penetration of proofing in the entire workflow, many users, especially those who are in the field, have difficulty meeting these prerequisites. Moreover, many companies are trying to use the same product in different production environments.

A successful solution starts with an accurate and objective assessment of the environment, whether it is locally or in the field. Do users have knowledge of color management and pay full attention to the consistency of the system? Have they adequately controlled their surroundings, such as lighting, temperature, and humidity? Does their network have enough bandwidth? Who will be responsible for installing and maintaining the proofing system? Who knows when the system needs maintenance or has advanced maintenance skills? How will the proofs be confirmed? Are users willing to invest in the color power management system—building a system and maintaining it?

A well-monitored system can be applied to a variety of fields and environments, but as the location of the proof changes, the above variables will also continue to affect the consistency between colors. [next]

At this time, hard copy proofing has become the ideal choice for most printing houses / print buyers. Nevertheless, screen proofing has also been recognized by more and more users. With our current experience and high speed, most successful screen proofing systems are installed where users can directly participate in color management and environmental control. Screen contract proofing, like all proofing systems, requires people to calibrate the monitor and verify the calibration status of the monitor with a closed-loop test. Only in this way can the color repeatability and accuracy be guaranteed.

If people can strictly follow these requirements, then screen proofing will become a viable solution. In the process of specific implementation, people also need to use expensive systems to control various variables on local and foreign sites. When customers check the calibration of the display, they must use high-quality inspection tools, while ensuring that the surrounding environment meets the requirements. For example, Time Inc. recently introduced a screen proofing system and is very satisfied with its work. Time Company has the ability to request and control the systems of all its distributors to ensure their normal operation. Although most of us may be reluctant to accept this type of collaboration and control, the growth trend of screen proofing systems will continue, because as long as it is used properly, it can help users save a lot of costs and production time.

For the same reason, users of a hard proofing system must be able to guarantee the consistency of the printer's colors. If not, they would better introduce a proofing system that can automatically adjust and calibrate.

Total cost of ownership

From our current experience, many companies have not considered the other costs associated with purchasing and operating the system when calculating the cost of the proofing system. Print buyers also have the same problem. They often only focus on one style, such as the cost of printing materials or consumables, while ignoring factors such as labor costs. In this case, the best way is to calculate the total cost of ownership (TCO) of the proofing system. This is a technology that can help organizations assess, manage, and reduce all costs associated with acquiring an asset within a certain time frame. These assets may be: factory buildings, vehicles, or software systems. The cost of purchasing hardware and software is the easiest factor to consider. The cost of consumables is also easy to calculate, but few users can think of the cost of consumable changes. For example, how do you know that your ink and paper supplier (whether intentionally or unintentionally) provides you with a product that does not meet the specifications? Do you have the tools and processes to inspect all factories in the field? How much does it cost to maintain this state?

Many users consider the service life of these systems when calculating the cost of hardware projects and infrastructure (network cost, physical space, etc.). In addition to maintenance costs, the upgrade path and cost will also account for a large proportion of the total cost of ownership of the system.

When calculating the labor cost, experienced users will not only consider the cost of installing equipment and training staff, but also consider the future training and maintenance costs. For the same reason, they will also consider the cost of replacing and upgrading color standards and characterization profiles over time. For example, the ICC-based proofing system itself is difficult to change in a decentralized environment as global standards change.

Some people may think that the cost of the screen proofing system is not too high, but for high-end displays, this is a wrong concept. Even for a low-end system, it may cost a certain amount of money to correct it. The display-based proofing system requires people to invest in a new set of technology, but also requires them to create an environment specifically designed to observe proofing. In addition, some systems also require pay-per-click, which also means that each sample produced will incur an additional cost.

Finally, there is the cost of violations. What happens when the proofing system cannot match the printing press? Who will be responsible for this? The cost of reprinting a job is enough to buy a top inkjet proofing system that can avoid such mistakes in advance. If the consequences of the error are more serious, then the printing house will have to lose both the user and the capital-it should of course be included in the total cost of ownership.

No matter how you calculate the cost, and no matter what you have calculated, most printing suppliers will participate in the process of recommending, explaining, and even supplying proofing systems to customers. Whether you like it or not, you have an obligation to understand and maintain the system and calculate its total cost of ownership.

Choose a standard

Adding color management to the workflow helps improve color interoperability (such as the ability to share color information between devices). Therefore, if we can adopt a unified standard, it will make things very simple. However, given the current global economic situation and the same content being reused in different places and different media, we have never found a unified standard. Therefore, the biggest problem we are facing now is how to integrate multiple different standards together.

In general, there are currently three types of standards: the first is custom or internal standards, which are mainly developed by printing houses to improve the efficiency of their pre-press and printing processes; the second is unofficial standards, which A standard that has been recognized by most people and has been used in production for a long time (such as Photoshop Sheetfed Offset and Adobe 98 RGB); the third is a recognized standard, which is used by trade associations and other organizations (such as IDEAlliance and ECI, etc.) A formally issued and approved standard.

We may not be able to describe in detail the development process and status of all standards in this article, but a quick tour of all the standards related to proofing is still very helpful to us.

The European Color Consortium (ECI) is a group of experts that is primarily dedicated to promoting media-independent color data processing in digital publishing systems. The Reference Color Space Gravure standard released by the organization has been successfully applied in the field of publishing gravure in Europe since the spring of 2002.

SNAP (Specifications for Newspaper Advertising Production) created a color standard for newspaper printing.

Fogra (Graphic Technology Research Association) created a color standard that can be used universally in Europe, and set a set of target values ​​for the proofing certification system, although it is only a set of European standards.

The International Standards Organization (ISO) has established a printing technical committee specializing in work related to color printing, standard setting, and measurement.

The International Color Council (ICC) is mainly dedicated to promoting an open, neutral, and cross-platform color management system in the industry.

IDEAlliance (American International Digital Enterprise Alliance) is an industry organization headquartered in the United States. It has always been committed to the development and research of printing industry best practices and standards. It is currently responsible for the management of: rotary offset printing parameter description (SWOP, mainly used for long-version rotary offset printing) and the basic requirements for commercial offset printing (GRACoL, mainly used for short-version commercial sheet printing).

Bond Paper

Uncoated Bond Paper,Bond Paper,Premium Quality Bond Paper,Offset Bond Paper

Puyang Longfeng Paper Co.,Ltd. ,