Some opinions on digital proofing

Some understandings of digital proofing

proofing is an intermediate link between prepress and printing. It is not only to check the work quality of plate making and proofreading personnel. It provides the basis and standard for the printing process, and is also an important means of quality management in the production process. As the post process of plate making. It is the reproduction process of image synthesis. It is the test of plate making effect. 2 as a printing, this paper includes energy conservation and environmental protection (automotive lightweight, smart glass (908, 0.00, 0.00%), aerogel, thermal insulation materials), the third industrial revolution process and materials (3D printing, sensors, superconducting materials, memory alloys), carbon industry chain (graphene, fullerene, carbon fiber, carbon nanotube), military materials (superalloy, titanium alloy, metamaterial) The pre process of 25 new materials involved in 8 categories of emerging electronic industries (liquid metal, amorphous and gold, OLED, flexible glass, optical film), mass industry (cemented carbide), energy (perovskite), and new chemical materials (adhesives, peek, polyphenylene sulfide). It is a standard for simulating printing for pilot production, seeking the best condition matching and providing ink color for formal printing. A qualified sample can be analog output with color separation film in the traditional way, and can also be output on the digital proofing equipment. in other words; Proofing can be divided into analog proofing and digital proofing. The fundamental difference between these two proofing methods is whether there is traditional film output. With the development of prepress digitization and networking technology, the digital process of prepress "metafilm" began to enter the prepress field as a powerful force, and the proofing technology is experiencing a new digital revolution. 1、 The characteristics of digital proofing, the so-called digital proofing, is a new proofing technology that directly outputs electronic originals after digital processing in electronic extraction. It uses a large format printer to directly output proofing in a digital way to replace the complicated process of film and printing in analog proofing. In the oncoming digital wave. People in the printing industry have high hopes for digital proofing. Industry experts believe that speed and stability have become the two major advantages of digital proofing. Mainly reflected in; First, good reducibility and stable color. Because the simulated proofing is mainly carried out by manual inking and pressure adjustment; Therefore, the effect cannot remain stable. If there is no digital proofing, the full digital process is adopted, so as to avoid the uncertainty of manpower in traditional proofing. Second; Fast proofing speed; Save time. Suitable for short edition printing. Print a high-quality folio sample, and digital proofing can be completed within 20 minutes. Simulation proofing takes 30-40 minutes. Third, there are few intermediate links, and the use of film is eliminated. On the one hand, it reduces the printing, film production and other links in the traditional proofing process. On the other hand, it also caters to the development trend of green printing, which is conducive to environmental protection. Fourth, because the whole process adopts digital operation, it is convenient to use and easy to operate. Fifth, remote digital proofing can be realized. Due to the application and development of network technology, digital files are transmitted to remote sites, and digital proofing is carried out by using proofing equipment, so as to provide users with digital proofs. This remote digital proofing breaks through the limitation of time and space, which is simple and practical. Of course, when digital proofing is showing its style; Its shortcomings have also been revealed, mainly reflected in: first, although the development of digital proofing technology is becoming more and more mature. But the technology of digital proofing is not very mature; In particular, there is a lack of unified standards for digital proofing equipment; It makes it difficult for operators and customers to adapt. Second, because some digital proofing uses frequency modulation points, the operation technology of this point is more complex in front of the diagram, which is also difficult for insiders who are used to amplitude modulation points. Third, the application scope of digital proofing is not widespread, and it can not meet the requirements of spot color proofing such as bronzing and silver ironing, which can be easily solved by traditional proofing. Fourth, the problem of consumables is relatively prominent. At present, special paper is required for digital proofing, which increases the printing cost and affects the credibility of the sample. Fifthly, the matching between the management software of digital proofing and the printing machine, imagesetter and other supporting equipment is still inconsistent. Therefore, in terms of the current development status of digital proofing; Due to its slow popularization and the cost of consumables, if the requirements for the cycle of live source are not tight, the general practitioners still choose the traditional simulation proofing. Looking at the development of the printing industry, from the perspective of foreign conditions, at present, advanced countries have begun to popularize digital proofing, and some developing countries have just begun to use it; Judging from the domestic situation, digital proofing technology has been widely used in gravure printing, but the development of offset printing is still in its infancy. At present, the promotion and popularization of digital proofing technology in Guangzhou, Shenzhen and other places is at the leading level in China. Today, with the coexistence of digital proofing and analog ordering, although the characteristics of digital proofing have appeared undoubtedly, there are still some areas that need to be improved in the development and application. Therefore, the comprehensive promotion also needs a process. Simply from the perspective of technological development, the digital proofing technology eliminates the interference of human and other external factors, greatly improves the reliability and stability of proofing output, and shortens the process flow as much as possible. In addition, the digital proofing can modify the samples at any time, which theoretically reduces the cost. With the popularization and popularization of digital proofing technology, it can completely solve many problems in analog proofing, such as long production cycle, unstable proofing quality and high cost, which has triggered another digital revolution in the printing field. It is foreseeable that digital proofing will replace analog proofing. 2、 Digital proofing technology digital proofing technology is becoming an indispensable part of the digital printing pipeline. There are four kinds of digital proofing technology: Digital semi continuous point adjustment technology; Continuous inkjet technology; Dye sublimation and dro on demand (dodl). In addition, other digital proofing technologies such as variable point transfer laser technology and hot wax technology have also been applied in the digital proofing system. But the specific application is not extensive. The following briefly introduces four commonly used digital proofing techniques. 1. Digital semi continuous modulation technology this technology is through the action of thermal laser, using four kinds of CMYK dyes to image on the sub sheets respectively, and then overlapping each sub sheet to form a proof sample. This technology simulates the dot increasing law, dot angle and other printing characteristics in printing; Provide inking for wop colors (sometimes gracol and eurocolor) by using special sub flakes. The dot proofing machine using laser imaging digital semi continuous modulation can not only compete with similar proofing in quality, but also surpass it. However, because the color values such as hue, saturation and aperture on the sub slice are relatively fixed, it is difficult for the equipment using the car continuous adjustment technology to transmit color points, which is a fatal disadvantage of the application of this technology. Manufacturers applying this technology are currently trying to develop a sub sheet production line for ordinary mercury color, but the effect is not ideal. Kodak is seeking a breakthrough in the other direction. The "color spectrum" created by its approval can be copied and output by using CMYK same screen background color. 2. Inkjet printing technology this technology is one of the medium and upper level technologies in the digital proofing market. It is also used for contrast proofing and content proofing. This technology mainly produces images by conveying continuous ink to the print head, and the ink wash is diverted to the substrate that needs pigment. Because inks can be synthesized into various colors, inkjet proofing machines are more flexible than digital semi continuous proofing machines in creating color dots. Although the digital proofing machine using this technology is slower than the dye thermal sublimation proofing machine in proofing speed, the quality and color accuracy obtained are higher than that of the thermal sublimation proofing machine. The disadvantages of this technology are: first, the printability of color needs to be further improved; Second, the ink flow is sometimes not smooth. 3. Dye thermal sublimation technology this technology is also one of the top-level technologies in the digital proofing market. It is also used for contrast proofing and content proofing. Dye sublimation proofing machine transfers pigments to the substrate through hot pressing, and generates images through a series of processes. Print samples of the same size; A dye sublimation proofing machine with good quality and an inkjet proofing machine have almost the same proofing speed. The disadvantages of digital proofing equipment with this technology are: first, it requires a special substrate, which increases the price of a single page; Second, rough proofing cannot be carried out on ordinary paper. 4. Modifiable inkjet technology modifiable inkjet technology is one of the lower level technologies in the market. It is a DOD inkjet system transferred from office printing to proofing market. It has many different models, such as hot proofing, pressure proofing and bubble inkjet proofing. They all share the same ink path rather than continuous oil inking. The performance of some of the devices is not stable enough, which can not be transferred in branches, and the printing speed is slow. At present, DOD inkjet technology is improving and perfecting the color processing and color description, so as to better imitate the actual printing color and printing environment. 3、 Digital proofing equipment for manufacturers of digital proofing, the biggest technical problem is whether they can provide points similar to cromain and matchprint proofing equipment, because this is the docking point between analog proofing technology and digital proofing technology. In the early stage of the development of digital proofing equipment, 3M's digital matchprint and Kodak's approval digital proofing T-system introduced two kinds of rich tone dot digital proofing equipment to the market respectively. Because these two devices use the method of "dithering" or "random continuous screen adjustment" to simulate halftone dots, the printed layers and colors are quite different from the actual printing process, which hinders the development of digital proofing. LRIs graphics company has experienced nearly 20 years of development and progress. As a high-end prepress proofing equipment, LRIs printer has attracted the attention of the pioneers of digital high-end proofing with its fine continuous output ability, and finally developed the market of digital high-end proofing. The following introduces several popular digital proofing equipment in the market. 1. Image rainbo imation rainbow company launched the first accurate color desktop proofing device with the world's ordinary plastic profit level of 1% and 3%, which has become one of the excellent members of today's proofing device family. Among the series of products launched by rainbow to the market, there are mainly two models: one is model 2730, which only updates the original model. Another newly launched 2740 model has a print area of 460 × 310mm, including the bleeding line, is exactly twice the size of A4 page. Rainbow274o can also print samples with metal effect and white ink effect, which provides a new application field for packaging and printing proofing and providing high-quality boutique proofing. Rainbow series proofing machine has excellent color correction software system, which can use professional apple machine for eight color separation. In the printing process, the effect of eight color printing is achieved through ink roller contact. Like most dye sublimation proofing machines, the rainbow2 series can only simulate one kind of printing machine, but it can better simulate printed matter by using color lookup table and dot expansion