How to choose suitable digital proofing

At present, there are many ways to export images and graphics, such as Computer to Proof, Computer to Film, Computer to Plate, and Computer to Press. To Paper / print, etc.

The usual proofing is after the production of the printed pages, the proofing is divided into digital proofing and mock proofing. Analog proofing is also called mechanical proofing. Its essence is analog printing. It is based on the printing conditions (such as paper, ink, and printing methods are basically the same). The printing plate is installed on the proofing machine to print and get proofs. The workflow is generally as follows: graphic output technology (obtained from the original version) → drying printing plate → simulation proofing → signing → printing plate production.

The purpose of proofing is the following aspects: 1 Inspection of prepress work, mainly to check the quality of the original. For example, whether the tonality of originals and the reproducibility of colors have met the requirements; whether layout size, image, text layout, rules lines, etc. are correct, whether there are omissions, etc., and if anything is wrong, it is necessary to make corrections. 2 printing reference samples, mainly for the official printing to provide proofs or basic parameters of printing, such as ink, dot reproduction range, so that printing to achieve standardized, standardized operation. 3 As the client's signature sample, it is mainly to provide the printed sheet to the customer. If the customer approves, it will sign and print on the printed sheet. Otherwise, the printing company will have to revise it.

Because of the complicated process, high cost, long production cycle, and large influence of human factors, analog proofing is gradually withdrawing from the stage of history. More and more printing companies use digital proofing technology. The so-called digital proofing is to print the page (or print) data produced by the color desktop system and output proofs directly through a color printer (inkjet, laser, or other means) without any form of simulation to check the image pages of the prepress process. Quality, providing reference proofs for the printing process, and providing the basis for users to sign and print.

The general digital proofing system mainly includes two parts: a color management system and an output device. The digital proofing system uses a variety of output devices, including thermal transfer output devices, thermal sublimation output devices, inkjet output devices, and laser output devices. In the color management system includes two core technologies, Postscript interpretation technology and color management technology. The Postscript interpreter guarantees that the user's documents can be interpreted correctly. The color management technology ensures that the proofing output results are consistent with the colors of the printed output. At present, many common color management softwares, such as Bestcolor Digital (acquired by EFI, Germany) Proofing software, Australia's BlackMagic digital proofing software, Malaysia's Star proof digital proofing software, and German GMG's digital proofing software.

The pre-press production process using digital printing is as follows:

Manuscript Digitization Process → Graphic Processing Technology → Digital Proofing Technology → Signing → Graphic Output Technology (Output Film or Direct Output Plate)

How should I buy my own digital proofing system? Generally speaking, when considering the digital proofing system, the main considerations are two aspects: First, technical specifications of the digital proofing system itself in terms of color reproduction and print quality; Second, the matching printing effect and adaptability to the printing production. For the products listed above, different softwares have their own characteristics. For example, the Best Color digital proofing system is currently the most widely used digital proofing system in the country. It enables general inkjet printers to also have good output quality. The performance of digital proofs. However, due to the defect of the ICC technology, if the output parameters are set incorrectly during the proof output, it will not be able to be output. In addition, there is also a deficiency in the reproduction of gray balance. While Australia's BlackMagic digital proofing software only controls the spot color when dealing with spot colors, the effect of the selective color correction function is not ideal, and the control of the level curve is not very accurate. Malaysia's Star proof digital proofing software corrects the color by adjusting the density, and the color difference ΔE between the color and the printed color adjusted by the Star Proof software is around 1.8. For the 1-BIT TIFF file processing powerful, you can output 200lpi precision image, but it requires a higher operator, you need to have a good understanding of the color. German GMG's digital proofing products have outstanding performance in single black, spot color and true dot proofing. Therefore, when users purchase digital proofing products, it is best to comprehensively consider according to the specific needs of the company and refer to the characteristics of each software.

When purchasing a digital proofing system, in addition to purchasing digital proofing software, digital output devices must also be selected. Color laser printing and thermal transfer/sublimation printing in digital output devices have not yet been widely adopted due to high equipment and printing costs. The precision of color laser printout cannot reach the precision of printed matter. Therefore, it is rarely used in the field of digital proofing. Color ink jet printing is the main product for digital proofing. There are also two types of current ink jet prints. Foaming inkjet printing technology and micro piezoelectric technology. The thermal foaming ink jet printer causes the ink to be ejected by instantaneously heating the thermistor so that ink droplets in the firing chamber expand to burst. Due to changes in the chemical composition of the ink at high temperatures, the resulting color stability is relatively poor. In addition, this type of printer nozzle is a consumable part, so the print quality has a good and bad change process, and the equipment using this technology is very difficult to maintain the stability of the color. Micro Piezo technology inkjet printing is the use of voltage changes to make the ink ejected from the nozzle, its nozzle is a solid piece, which fundamentally ensures the stability and consistency of the color, can meet the digital proofing requirements of the output device At the same time, it also greatly reduces the cost of the output. Micro-piezoelectric technology is a patented product of Epson Corporation. The use of intelligent ink droplet conversion technology can make the smallest droplet of the output can reach 4ppl, so as to meet the requirements of the tiny dots of the printed matter, and the images and text are more clear.




Source: PACK.CN