The maturity and development of CTP technology has greatly changed the production, management and even business models of printing and related industries, creating new business opportunities and markets, and bringing many production benefits to the manufacturers. It has become a magic weapon for enterprises to win in the fierce competition. However, in the face of new technologies and new processes, due to the experience of operators and the limitations of peripheral equipment, etc., there are often some problems that need to be paid attention to in practical work. At the same time, because of the existence of these problems, the advantages of CTP can not be fully reflected, but it hinders the improvement of production efficiency of enterprises, and the bad use of individual users also has a negative impact on the expansion of CTP market. Therefore, managers engaged in CTP work must be proficient in technology, use various management knowledge, co-ordinate the overall situation in the complicated pre-press work, master and control the work process, and make the work in an orderly manner.
First, the CTP publishing linearization aspect
Color management in the CTP process is the focus and difficulty of the CTP technology. The ICC characteristic curve that accurately reflects the characteristics of the device determines the effect of color management. Therefore, the generation and application of the ICC characteristic curve has become the top priority of color management.
First of all, we know that the current violet laser CTP is an indispensable part of linearization due to its photosensitive properties and the characteristics of the processor. Some users are always suspicious of the linearization curve when they use it, and they are not very confident about the linearity of the device. After a lot of use and practice, this kind of worry is completely unnecessary. Some monitoring methods in the use process can fully guarantee the accuracy of the dot reduction.
1. Control of ambient temperature and humidity. In a safe photosensitive environment, strict control of temperature and humidity is very beneficial for the reproduction of CTP dots. Generally, it is necessary to ensure that the ambient temperature is around 23 and the humidity is between 50-60.
2. Precise control of the PH value. The developer of the platen machine is periodically replaced as required. The developer in the developing tank of the machine is measured before publication every day to ensure that the pH of the developer is in the range of 12±0.25 at 28 °C. If not enough, supplement the supplement separately.
3. Measurement of the plate tester. In order to verify the accuracy of the value of the publishing site, a gray scale output can be produced on the curved position on the plate. After the plate is finished, the actual dot value is measured, and the difference between the value and the required value is checked, but pay attention to the measurement. The value of the comparison is the value after adding the inverse compensation curve.
After ensuring that there are no problems with the above three points, the obtained dot values ​​are completely free of problems. They have become a favorable weapon for controlling the restoration of outlets.
Of course, the PH value reaches a relatively stable state, and it takes a period of monitoring and adjustment. Due to the user's use of the size of the plate and the difference in the environment, the pre-installation period may be a process of exploring the PH value. During this period of time, the real-time monitoring of the publication can be done, and we can find a suitable replenishment amount. Within a period of time, if the PH value does not change significantly during the publication process, it indicates that the adjustment has met the standard. Users can follow the hardware engineers to learn the adjustment skills, and you can make some adjustments when you need them.
Second, CTP publishing and printing compensation
Sometimes users tend to put forward some ideas on the plate making process curve according to the needs of their products (such as the black and blue dot of the character album color, the shadow of the jewelry album, etc.), and take it to the traditional film. Printing on the prints for comparison. Since the acquisition of the CTP process curve is a time-consuming, labor-intensive and cost-intensive process, it is basically obtained by printing test files, collecting data and making accurate measurements. The traditional film printing is only by simple addition. The time-reduction version is finely adjusted. After repeated tests on the machine, although it is not always possible to achieve a completely accurate effect, the customer believes that the timeliness is more obvious than the CTP. Thus gradually entered a traditional film than the CTP convenient and practical misunderstanding.
Then we return to the root of the problem, it is not difficult to find that all the requirements are based on an uncertain factor: they are deliberately adjusting the existing plate making process according to their own subjective ideas. We believe that “the color of the characters must be soft and ruddy, and the shadows of the jewels need to be complete and delicate.†These are the relevant treatments on the plate making without actual standards. However, have we noticed that the CMYK value on the source file is far from the actual value of the dot network. At the same time, due to the adjustments made by these uncertain factors, in the case that the process parameters cannot be recorded in detail, the same work will print different results on the same machine after the next printing.
So what we need to do is to set a different standard for different needs. Regardless of the normal operating specifications or the abnormal process standards that are specifically required to be changed, different process curves can be established as long as relevant reference data is available. The newly established process curve is closely integrated with the computer and process software, and there is no inconsistency in output at different times, which can ensure the accurate consistency of the network to the version. Of course, in the actual operation, it is not desirable to have too many process curves. Too many process curves are ultimately inconvenient to manage, and the production process curve is not practical.
At present, we are based on the international standard of ISO12647-2, the domestic standard of GB17934-2 and the actual printing situation in China to develop the CTP process curve of user characteristics. In order to occupy the quality advantage in the fierce competition, printing enterprises should pay attention to the standard. Application, and strive to be in line with international standards in product quality management. [next]
Third, CTP digital proofing aspects
After the process curve is determined, the standard print profile is printed according to the standard, and the rest of the work is to make a digital proof. After a series of measurement productions, once the digital proofing was played, the user couldn't help but start to worry. "This digital proofing is so beautiful, can the printing keep up?" Most users may still prefer the traditional proofing of round flattening, but After understanding the shortcomings of the traditional, their views have also changed.
1. Analysis of advantages and disadvantages of traditional proofing
The advantages of traditional proofing mainly include the following:
(1) The production process of the proofing plate and the printing plate are relatively close, and in theory, the actual printing can be better simulated;
(2) Using the same rasterized data for proofing and printing, potential problems can be found through proofing, such as moiré, layout and fonts. At present, digital proofing after RIP can also be done;
(3) Good performance for trapping and ink opacity in proofing of spot colors and metallic colors.
The main disadvantages of traditional proofing are as follows:
(1) High technical content, requires professional technicians to obtain accurate proofs, and labor intensity;
(2) Requires higher investment, including the cost of film, printing plates, paper, and ink;
(3) There are many processes involved, the cost is high, and the processing cycle is long.
2. Analysis of advantages and disadvantages of digital proofing
The digital proofing technology is completely digitally controlled, changing the complex printing process in the past while reducing costs. Moreover, the stability of plate making and printing quality is greatly improved.
The advantages of digital proofing mainly include the following:
(1) No need to output film or make a plate cylinder, which can reduce the cost while shortening the production cycle;
(2) Samples made based on inkjet technology are generally more stable in quality;
(3) Digital proofing is an important part of digital printing, and its unique stability can provide a standard for the entire printing process, providing a strong guarantee for the improvement of printing quality.
The main disadvantages of digital proofing are as follows:
(1) Some digital proofing systems cannot ensure the integrity of document data, and proofing after RIP can be done;
(2) The digital proofing system with the function of processing the net tone requires a higher cost;
(3) Spot colors and metallic colors cannot be accurately reproduced, and a specific system must be used.
Of course, digital proofing is not completely close to print. The difference is mainly due to the difference in materials and imaging methods. In addition, the digital samples converted based on the ICC principle match most of the colors, but for some reasons of the device, there may be compression in the super color gamut partial conversion. The problem, but these are no way to avoid any digital proofing software, users also need to try to change the customer's concept, and strive for cost savings and efficiency.
3. Handling of digital proofing color problems
Many times, because the processing of the document picture is not standardized, the actual proofing color is different from the color perceived by the customer. In this case, there must be a firm belief that the digital proofing is completely ok. Digital proofing is made with reference to the standard printing characteristics file. It can correctly reflect the actual color development of the printing. In addition, the stability of the digital proofing equipment is unmatched by other equipment. It is basically impossible to suddenly appear color inaccuracy. of.
In fact, the problem arises in the image processing of the front-end design and the color reproduction of the display. These involve a complete color management scheme. It is necessary to ensure the consistency of the images in various devices, and truly realize the "what you see and gain". The perfect effect. Here, the adjustment of the front-end input device and display device is not introduced, and the principle and the principle of digital proof matching printing are completely indistinguishable, that is, the essence of color management.
Undoubtedly, with the continuous development and improvement of color management technology, digital proofing will show greater advantages and dominate in the printing process.
In the production practice, summarize the following points that need attention:
1. Keep the print as stable as possible. Enterprises should establish a set of effective printing standards, especially in controlling printing density and dot gain, and require operators to resolutely execute in the printing process, and control the indicators within the error range.
2. Make sure the digital proofing device is in a normal state. The machine is often used to detect and adjust the machine so that the digital proofing device is always in a normal state, ensuring consistent printing results.
3. Strict control of the printing characteristics test version, whether the ICC characteristic curve of the CMYK printing source accurately reflects the characteristics of the printing equipment depends entirely on good printing control.
4. In theory, different printing conditions correspond to different ICC characteristic curves. However, for the common printing and the general visual perception of the human eye, it is sufficient to set a few ICC characteristic curves reflecting the printing characteristics for the common coated paper or matte paper.
Fourth, CTP printing
The current CTP system is generally used by large and medium-sized printing companies. Most of them have several, dozens, or even dozens of different types of printing machines, such as Heidelberg. Manroland, KBA, Mitsubishi, Beiren, etc., including single-sided presses and double-sided presses, as well as sheetfed presses and rotary presses.
It is well known that on each lithographic press, there are 125 variables that need to be controlled, so maintaining print consistency becomes a difficult goal. In addition, the inherent and unchangeable characteristics of the device itself: on the one hand, the machine printing characteristics of different models are definitely different, we can not guarantee that different machines can print the same effect; on the other hand, even the same model Machines are different in terms of their use time, machine wear and other factors. The diversity of such products must be in conflict with the state of the printing machine, and users often encounter situations where certain products can only be printed on a fixed machine. Therefore, the consistency of the printing effect of the device has become the most annoying thing for today's CTP users.
At the same time, if there is no perfect equipment management mechanism and good working environment, such as poor equipment maintenance environment, incorrect machine operation habits, etc., it will inevitably lead to the depreciation of printing equipment, and the quality of printed jobs produced will not be produced. There will be great value and naturally cannot adapt to the current fierce competitive environment.
In order to solve these problems, we must first adhere to best practices and control workflow to better manage the printing press, regularly perform maintenance and inspection of the equipment, and resolutely prevent the machine from working. Machines that require problems to be adjusted must be adjusted to their optimum condition and may be assisted by the machine supplier if necessary.
Secondly, in the standard state, the work of CTP process is completed, the printing compensation curve of different machines is established, and the standardization and dataization of the whole process work are guaranteed to improve and solve the above problems.
Today, the development of CTP technology is changing with each passing day. We must analyze the specific problems in the process of continuous learning and exploration, and there are no ready-made formulas and rules to copy. In addition, CTP technology also has a lot of skills, learning and using these skills will greatly improve work efficiency.
The maturity and development of CTP technology has greatly changed the production, management and even business models of printing and related industries, creating new business opportunities and markets, and bringing many production benefits to the manufacturers. It has become a magic weapon for enterprises to win in the fierce competition. However, in the face of new technologies and new processes, due to the experience of operators and the limitations of peripheral equipment, etc., there are often some problems that need to be paid attention to in practical work. At the same time, because of the existence of these problems, the advantages of CTP can not be fully reflected, but it hinders the improvement of production efficiency of enterprises, and the bad use of individual users also has a negative impact on the expansion of CTP market. Therefore, managers engaged in CTP work must be proficient in technology, use various management knowledge, co-ordinate the overall situation in the complicated pre-press work, master and control the work process, and make the work in an orderly manner.
First, the CTP publishing linearization aspect
Color management in the CTP process is the focus and difficulty of the CTP technology. The ICC characteristic curve that accurately reflects the characteristics of the device determines the effect of color management. Therefore, the generation and application of the ICC characteristic curve has become the top priority of color management.
First of all, we know that the current violet laser CTP is an indispensable part of linearization due to its photosensitive properties and the characteristics of the processor. Some users are always suspicious of the linearization curve when they use it, and they are not very confident about the linearity of the device. After a lot of use and practice, this kind of worry is completely unnecessary. Some monitoring methods in the use process can fully guarantee the accuracy of the dot reduction.
1. Control of ambient temperature and humidity. In a safe photosensitive environment, strict control of temperature and humidity is very beneficial for the reproduction of CTP dots. Generally, it is necessary to ensure that the ambient temperature is around 23 and the humidity is between 50-60.
2. Precise control of the PH value. The developer of the platen machine is periodically replaced as required. The developer in the developing tank of the machine is measured before publication every day to ensure that the pH of the developer is in the range of 12±0.25 at 28 °C. If not enough, supplement the supplement separately.
3. Measurement of the plate tester. In order to verify the accuracy of the value of the publishing site, a gray scale output can be produced on the curved position on the plate. After the plate is finished, the actual dot value is measured, and the difference between the value and the required value is checked, but pay attention to the measurement. The value of the comparison is the value after adding the inverse compensation curve.
After ensuring that there are no problems with the above three points, the obtained dot values ​​are completely free of problems. They have become a favorable weapon for controlling the restoration of outlets.
Of course, the PH value reaches a relatively stable state, and it takes a period of monitoring and adjustment. Due to the user's use of the size of the plate and the difference in the environment, the pre-installation period may be a process of exploring the PH value. During this period of time, the real-time monitoring of the publication can be done, and we can find a suitable replenishment amount. Within a period of time, if the PH value does not change significantly during the publication process, it indicates that the adjustment has met the standard. Users can follow the hardware engineers to learn the adjustment skills, and you can make some adjustments when you need them.
Second, CTP publishing and printing compensation
Sometimes users tend to put forward some ideas on the plate making process curve according to the needs of their products (such as the black and blue dot of the character album color, the shadow of the jewelry album, etc.), and take it to the traditional film. Printing on the prints for comparison. Since the acquisition of the CTP process curve is a time-consuming, labor-intensive and cost-intensive process, it is basically obtained by printing test files, collecting data and making accurate measurements. The traditional film printing is only by simple addition. The time-reduction version is finely adjusted. After repeated tests on the machine, although it is not always possible to achieve a completely accurate effect, the customer believes that the timeliness is more obvious than the CTP. Thus gradually entered a traditional film than the CTP convenient and practical misunderstanding.
Then we return to the root of the problem, it is not difficult to find that all the requirements are based on an uncertain factor: they are deliberately adjusting the existing plate making process according to their own subjective ideas. We believe that “the color of the characters must be soft and ruddy, and the shadows of the jewels need to be complete and delicate.†These are the relevant treatments on the plate making without actual standards. However, have we noticed that the CMYK value on the source file is far from the actual value of the dot network. At the same time, due to the adjustments made by these uncertain factors, in the case that the process parameters cannot be recorded in detail, the same work will print different results on the same machine after the next printing.
So what we need to do is to set a different standard for different needs. Regardless of the normal operating specifications or the abnormal process standards that are specifically required to be changed, different process curves can be established as long as relevant reference data is available. The newly established process curve is closely integrated with the computer and process software, and there is no inconsistency in output at different times, which can ensure the accurate consistency of the network to the version. Of course, in the actual operation, it is not desirable to have too many process curves. Too many process curves are ultimately inconvenient to manage, and the production process curve is not practical.
At present, we are based on the international standard of ISO12647-2, the domestic standard of GB17934-2 and the actual printing situation in China to develop the CTP process curve of user characteristics. In order to occupy the quality advantage in the fierce competition, printing enterprises should pay attention to the standard. Application, and strive to be in line with international standards in product quality management. [next]
Third, CTP digital proofing aspects
After the process curve is determined, the standard print profile is printed according to the standard, and the rest of the work is to make a digital proof. After a series of measurement productions, once the digital proofing was played, the user couldn't help but start to worry. "This digital proofing is so beautiful, can the printing keep up?" Most users may still prefer the traditional proofing of round flattening, but After understanding the shortcomings of the traditional, their views have also changed.
1. Analysis of advantages and disadvantages of traditional proofing
The advantages of traditional proofing mainly include the following:
(1) The production process of the proofing plate and the printing plate are relatively close, and in theory, the actual printing can be better simulated;
(2) Using the same rasterized data for proofing and printing, potential problems can be found through proofing, such as moiré, layout and fonts. At present, digital proofing after RIP can also be done;
(3) Good performance for trapping and ink opacity in proofing of spot colors and metallic colors.
The main disadvantages of traditional proofing are as follows:
(1) High technical content, requires professional technicians to obtain accurate proofs, and labor intensity;
(2) Requires higher investment, including the cost of film, printing plates, paper, and ink;
(3) There are many processes involved, the cost is high, and the processing cycle is long.
2. Analysis of advantages and disadvantages of digital proofing
The digital proofing technology is completely digitally controlled, changing the complex printing process in the past while reducing costs. Moreover, the stability of plate making and printing quality is greatly improved.
The advantages of digital proofing mainly include the following:
(1) No need to output film or make a plate cylinder, which can reduce the cost while shortening the production cycle;
(2) Samples made based on inkjet technology are generally more stable in quality;
(3) Digital proofing is an important part of digital printing, and its unique stability can provide a standard for the entire printing process, providing a strong guarantee for the improvement of printing quality.
The main disadvantages of digital proofing are as follows:
(1) Some digital proofing systems cannot ensure the integrity of document data, and proofing after RIP can be done;
(2) The digital proofing system with the function of processing the net tone requires a higher cost;
(3) Spot colors and metallic colors cannot be accurately reproduced, and a specific system must be used.
Of course, digital proofing is not completely close to print. The difference is mainly due to the difference in materials and imaging methods. In addition, the digital samples converted based on the ICC principle match most of the colors, but for some reasons of the device, there may be compression in the super color gamut partial conversion. The problem, but these are no way to avoid any digital proofing software, users also need to try to change the customer's concept, and strive for cost savings and efficiency.
3. Handling of digital proofing color problems
Many times, because the processing of the document picture is not standardized, the actual proofing color is different from the color perceived by the customer. In this case, there must be a firm belief that the digital proofing is completely ok. Digital proofing is made with reference to the standard printing characteristics file. It can correctly reflect the actual color development of the printing. In addition, the stability of the digital proofing equipment is unmatched by other equipment. It is basically impossible to suddenly appear color inaccuracy. of.
In fact, the problem arises in the image processing of the front-end design and the color reproduction of the display. These involve a complete color management scheme. It is necessary to ensure the consistency of the images in various devices, and truly realize the "what you see and gain". The perfect effect. Here, the adjustment of the front-end input device and display device is not introduced, and the principle and the principle of digital proof matching printing are completely indistinguishable, that is, the essence of color management.
Undoubtedly, with the continuous development and improvement of color management technology, digital proofing will show greater advantages and dominate in the printing process.
In the production practice, summarize the following points that need attention:
1. Keep the print as stable as possible. Enterprises should establish a set of effective printing standards, especially in controlling printing density and dot gain, and require operators to resolutely execute in the printing process, and control the indicators within the error range.
2. Make sure the digital proofing device is in a normal state. The machine is often used to detect and adjust the machine so that the digital proofing device is always in a normal state, ensuring consistent printing results.
3. Strict control of the printing characteristics test version, whether the ICC characteristic curve of the CMYK printing source accurately reflects the characteristics of the printing equipment depends entirely on good printing control.
4. In theory, different printing conditions correspond to different ICC characteristic curves. However, for the common printing and the general visual perception of the human eye, it is sufficient to set a few ICC characteristic curves reflecting the printing characteristics for the common coated paper or matte paper.
Fourth, CTP printing
The current CTP system is generally used by large and medium-sized printing companies. Most of them have several, dozens, or even dozens of different types of printing machines, such as Heidelberg. Manroland, KBA, Mitsubishi, Beiren, etc., including single-sided presses and double-sided presses, as well as sheetfed presses and rotary presses.
It is well known that on each lithographic press, there are 125 variables that need to be controlled, so maintaining print consistency becomes a difficult goal. In addition, the inherent and unchangeable characteristics of the device itself: on the one hand, the machine printing characteristics of different models are definitely different, we can not guarantee that different machines can print the same effect; on the other hand, even the same model Machines are different in terms of their use time, machine wear and other factors. The diversity of such products must be in conflict with the state of the printing machine, and users often encounter situations where certain products can only be printed on a fixed machine. Therefore, the consistency of the printing effect of the device has become the most annoying thing for today's CTP users.
At the same time, if there is no perfect equipment management mechanism and good working environment, such as poor equipment maintenance environment, incorrect machine operation habits, etc., it will inevitably lead to the depreciation of printing equipment, and the quality of printed jobs produced will not be produced. There will be great value and naturally cannot adapt to the current fierce competitive environment.
In order to solve these problems, we must first adhere to best practices and control workflow to better manage the printing press, regularly perform maintenance and inspection of the equipment, and resolutely prevent the machine from working. Machines that require problems to be adjusted must be adjusted to their optimum condition and may be assisted by the machine supplier if necessary.
Secondly, in the standard state, the work of CTP process is completed, the printing compensation curve of different machines is established, and the standardization and dataization of the whole process work are guaranteed to improve and solve the above problems.
Today, the development of CTP technology is changing with each passing day. We must analyze the specific problems in the process of continuous learning and exploration, and there are no ready-made formulas and rules to copy. In addition, CTP technology also has a lot of skills, learning and using these skills will greatly improve work efficiency.
Article source address: http://
Reed Diffuser,Nest Diffuser,Reed Diffuser Sticks,Reed Sticks
Jiangsu Raymeel Home Decoration Co., Ltd. , https://www.raymeelhome.com