Some points to note when PDF printing

With the increasing maturity and perfection of the prepress digitalization process, more and more prepress production departments receive electronic documents in commercial printing. These electronic files are the most common as PDF files. It is a standard and stable print-compliant unit file. Of course, there are also typographic links to the scattered image files, such as Founder Feiteng, Quark, Pagemaker, and Indesign. In addition, PS and other file formats are also the original documents often encountered by printing companies. And some of these electronic manuscripts are often accompanied by customer's digital manuscripts or sample books. In general, the printing factory prepress production department will organize these different kinds of file formats into file formats that are commonly used in the factory's prepress process, such as PS or PDF file format, and then go through the prepress workstations, such as Founder Streams. , and then carry out printing standardization, color conversion, trapping, typesetting, etc., and finally Rip, and then publish.

When there are customer's manuscripts, such as digital manuscripts, and the printing colors are required to follow the digital manuscripts as much as possible, the inspection of electronic manuscripts before printing is particularly important. Now for the standard PDF or PS file, use Prefight pre-flight inspection software, which can check the file for trapping, image format, trapping, font, image resolution, color profile, etc., to confirm the contents of the file. Meet the printing standard.

Pre-print color preview

For electronic documents of different customers, and with digital color proofing originals, the printing factory will not follow the customer's color draft according to their own printing standards. What effect can the color effect achieve? Due to the failure to do a color preflight, it was not uncommon for printers to find that printers couldn't bring the printers to the printers after printing. In order to solve this kind of problem, it is necessary to perform color pre-check on the customer draft. This will be an indispensable part of the full-process color management of printing plants.

To conduct a color preflight for printing, a printing factory is required to do a preflight proofing or evaluation of the customer's electronic manuscript in the factory's printing standard or printing state's color effect. In order to facilitate the electronic manuscripts and digital scripting for different customers, the color processing is performed in advance to achieve the best color matching. In actual production, customers have different requirements for printing factories with different colors. According to the simulabilities of different manuscripts, the printing factory can choose different color pre-test methods. This takes into account both cost and customer satisfaction with color. After all, economic benefits make the lifeblood of an enterprise survive.

Epson inkjet digital drafts are the most common customer's manuscripts for commercial printers. Of course, there are also laser drafts used for printing and coloring. For the uneven quality of the original and the effect, as well as the simulation of the printing effect, if you do not pre-print proofing, color pre-check, the printing color effect will be inestimable.

There are many times when the customer's digital copying is colorful and the colors are bright and saturated. Sometimes the laser drafts are dimmed, and the colors are grayish or partial. Meet these guest scripts must be color preflight. Here's a brief introduction to the common problems of prepress color preflight.

Firstly, for the customer-original electronic document and the digitally-colored manuscript, check the color to use the digital version of the printout. However, the digital proofing requirements for the printing factory are relatively high. First of all, the printing factory shall test the color characteristics of the printing press in accordance with certain standards and conditions according to certain printing standards, such as national standard, SWOP, GRACOL, etc., and collect the color characteristics of the printing press under the standard printing state as the printing color of the entire printing factory. Property file. Because everybody knows, the gamut space of the general monitor's gamut space and the digital proofing that did not do calibration are larger than the common four-color printing gamut space, the final color effect of the prepress image should be realized with the printing color. Therefore, in the pre-press color calibration, we must use the factory or close to the factory's four-color printing color profile to pre-display or as a printing model to be printed source files. This kind of digital proofing is only meaningful when used for pre-checking. At the same time, for the digital proofing that is used to pre-print pre-inspection colors, it is necessary to regularly perform color calibration and to compare the difference between digital samples and printing samples to follow up the color-up effect of printing.

Second, use the screen soft proofing color correction. This is the most practical color correction method. From the soft proofing test results, the use of soft proofing as a printing sample is currently at the domestic or exploration stage, and it is still to be developed to use it instead of digital samples. However, using the screen soft proofing to check the color pre-check of the customer's electronic manuscript under the factory's printing color characteristics can still be used. The premise of this kind of screen soft proofing for prepress color pretest is:

1. Customers have higher requirements for printing colors and colors are as similar as possible.

2. The monitor used for soft proofing is best to use an industry-certified display such as EIZO. Ordinary monitors used for soft proofing of the screen are not realistic. Can not meet the requirements of pre-printing color before printing.

3. The monitor should be calibrated regularly and evaluated. At the same time, the color pre-display should be used to accurately print the color profile.

4. Compare the soft proofing color with the ambient light source of the customer's color draft when the customer's draft is to be measured.