On the application of digital proofing

With the development of computer direct plate making (CPT) in recent years, the industry generally believes that this technology is bound to replace the existing film making process, but its development has received some obstacles. Because the plate making process using film can still provide some flexibility for manual modification, such as typography or partial version change. However, direct plate making is in place, and the plate making machine is used to image directly on the plate. All the imaging data cannot be lost, otherwise the whole page needs to be re output. In other words, compared with ctfilm, ctplate is more strict in a set of reliable digital workflow to properly handle the production process from designer to printer. Therefore, the most controversial issue is not whether the laser can be used to directly produce high-precision points on the plate, but whether there is a set of recognized digital workflow to replace the existing production methods. In the whole process, we need to consider: digital proofing, computer collage, flexibility of production efficiency modification, cost, trapping, self-made film and other issues. The following is an introduction to the requirements and technology of digital proofing

comparison between digital proofing and traditional proofing

whenever the effect of digital proofing is mentioned, the traditional proofing will generally be used as the benchmark for comparison. Although such comparison is logical, it is often easy to miss the benefits brought by some functions attached to digital proofing. I will try to objectively compare the differences between the two in three areas, including quality, cost and efficiency

quality effect

color simulation ability - since the traditional proofing machine also uses ink to image, various faults caused by the equipment's own reasons or shortcomings within the warranty period should be provided with free technical services and maintenance by our party; The gamut it can express is very close to printing. In terms of digital proofing, some equipment can also use color ink with similar ink composition, and the performance of color gamut is also very similar to printing. However, the cost of both ink and machine is very high (generally, the equipment is between 500000-1.5 million, depending on the format and accuracy). While other common color printers, such as inkjet or thermal sublimation, can express more color gamut than printing ink, and the cost is very low. The key is how to use too rich color gamut to simulate the color gamut of printing ink, which completely depends on the color management technology of individual manufacturers

flower simulation ability - traditional proofing has an absolute advantage in this regard. Because they use the same set of film printing plate as printing. If digital proofing needs to simulate flowers, on the one hand, it will cost more than one million yuan to purchase high-precision equipment, but the effect in exchange is difficult to be consistent with the real printing effect. For example, the precision of the digital proofing machine is 2000, and the precision of the special Rockwell hardness tester for pipes/3000dpi, while the precision of the Phototypesetter is 2400/3600dpi. The flowers produced by the two are completely different. Most of the devices that can simulate flowers on the market can only meet the visual requirements of customers

stability - because traditional proofing machines use human ink and adjust pressure, the effect is very unstable. Insiders have this experience: This is that the same set of films are taken out for proofing, and the effect is usually different. Digital printing is automatic imaging, which can be very stable. Of course, if the equipment is of poor quality, such as the ink head is often blocked, it will also cause unstable factors. However, it is not difficult to find more stable equipment on the market

reliability - traditional proofing uses the same film as printing, which is highly reliable. Digital proofing can be considered at three levels:

1. If the rip of output proofing is completely different from that of the final plate making system, the reliability is low

2. For example, the rip of output proofing is the same as the science and education film system, but it needs to be reprocessed before imaging, so the reliability is high

3. If the same set of data processed by Rip can be used as proofing and plate making, the reliability will be very high. Because in the whole process, in addition to human factors, the most likely difference in operation is rip operation. The three methods mentioned above are available on the market

cost effectiveness:

investment cost - in this regard, traditional proofing is very inferior to digital proofing. Because with the same production capacity, if two sets of folio four-color proofing are completed in one hour, the investment in traditional equipment requires four sets of printing machines, supporting plate printing and printing equipment, plus the required staff and a large plant, the investment is about NT $2million. The investment of digital proofing can be 10000 yuan, depending on the quality requirements, while the additional labor is close to zero. In terms of material cost, the cost of traditional proofing paper and ink is very low, and the higher proportion of cost is plate material and potion. In terms of digital proofing, a folio format is about 20-150 yuan, depending on individual printers. In general, the return on investment of digital proofing (to a certain degree of quality recognition) can be much higher than that of traditional proofing

performance:

production speed - on the surface, digital proofing imaging speed is faster. A common printer on the market can complete a folio layout of the same quality in 20 minutes. The traditional proofing, regardless of size, does not include the time of making up, printing and printing. The single proofing action usually takes 30-40 minutes, but this is only a comparison of producing a proofing. When more than one color proofing needs to be produced, the discrimination between the two speeds is relatively close. Go deep into the production line 1 of the enterprise to investigate and study a variety of simulation capabilities - most of the digital proofing machines mentioned above can express more color gamut than printing inks. With rich color gamut and good color management software, digital proofing can not only simulate the effect of printing, but also simulate other production effects, such as silk printing, digital printing, inkjet posters, and even simulate the performance under high-speed rotary printing machines, which can better meet the requirements of increasingly diversified output in the market. The most common example is that a set of advertising design needs to be publicized through different media

multiple format capabilities - the complete digital proofing system can not only simulate the color effect of an output medium, but also automatically adjust the color of the image in the file according to the needs of different outputs, so that the operator can truly achieve the automatic workflow without manual modification. The above two digital proofing features are lacking in traditional proofing

selection of digital proofing

digital proofing can be basically divided into three categories:

1. Design proof design proofing, only for layout design

2. Color proof, aiming at color effect

3. Screen proof proofing, aiming at color and flower effect at the same time

on the whole, color proof has the most comprehensive uses and high selectivity, which can achieve the best cost-effectiveness. In fact, there are many kinds of color printers available on the market, and their main imaging technologies include laser printing, thermal wax transfer, thermal sublimation, inkjet, etc. And inkjet can be said to be the mainstream of high-end products