Proofing Technology: New Forces and Traditional Technology Counterbalance

Proofing technology has always been the most important thing in prepress technology, and it is also the focus of people's attention. The quality of proofing is directly related to the success of subsequent production. In order to meet the needs of different readers, Winslow has specially launched this article on soft proofing technology and the advantages and disadvantages of inkjet proofing technology, hoping to give some inspiration to readers concerned about this issue.

After gaining people's extensive trust in the printing industry, color management technology now appears to have become an important part of process control for all print production companies. Through testing and measurement, users of color management systems can change the way colors are processed to match presses with different characteristics. All printers should generate common characterization files for each press—in fact, many production consultants recommend that the printer create a characterization file for each possible combination of paper, press, and color sequence.

A customized profile can provide the most accurate color for each specific printer in a printing house. Difficulties in practical applications prevent everything from being blocked, and do not prevent faithful users of color management from collecting a large number of features for each press. Description file. In fact, such fine-tuning is opposed to the interests of print buyers and advertising agencies.

Although we are all rejoiced at the growth of this repeatable new world and people's ability to match the final proofs, buyers of prints still need the ability to design exquisite products without knowing who will ultimately print. Color management may be a very effective method of control, but it still does not inhibit the desire of agents to seek the lowest price and fastest turnaround speed.

Metal and glazing effect with soft proofing

Although CMYK soft proofing is in its peak period, people's increasing frequency of application of glazing and metallic colors has objectively forced people to continue to use hard-copy proofs to demonstrate the printing effect. In order to reflect this effect in soft proofing, Stonecube introduced PrintDevizor.

We show a geometric metal pattern CMYK perspective on the cover of this month’s Graphic Arts magazine. The original of this image comes from PrintDevizor's video. The British company recently donated 50 copies of PrintDevizor to RIT, of which 35 were used in its School of Print Media.

PrintDevizor was once exhibited on Print 05. It uses a software program to generate dynamic files that represent hot stamping, embossing, and partial glazing on the screen. As the reflectivity shifts, the rotatable 3D image model can also simulate metallic colors, UV gloss, flash and fluorescent ink printing effects.

Independent graphics files for each printing effect are imported into the PrintDevisor software, which also selects the desired effect based on the input artwork. These include paper texture (smooth matt paper, fine paper, rough paper, satin paper, etc.), processing, spot colors (standard, metallic and fluorescent inks), foil stamping, embossing, laminating, Light and other categories, each category has a variety of options. The software also features metalFX and ink-on-foil (printed on metal foil) simulation capabilities. Its laydown command can be changed to predict what kind of machining should be done first in the production process. Can people use the results of color management without knowing who is going to print? The answer is yes. Because there is now the latest standard ICC output profile. By continuing to collect and analyze data from real printing companies, the SWOP and other standardization committees have come up with a series of performance files that can be achieved by representative printers. These feature profiles, with names such as "US Web Coated (SWOP) v2" or "Europe ISO Coated FOGRA27," embody the hard work that people have devoted over many years to the characterization of the ideal effects of the print reproduction process.

After having a characterization document based on the latest standards, more and more advertising agencies and photo studios have chosen to output their own digital proofs that meet the quality of the contract. The Straub Collaborative in Portland is such a company. The main customers of this digital imaging studio include an international retailer who designs and prints jobs in Europe and the United States. Straub used the Epson 4800 inkjet printer with GMG ColorProof software to make proofs for the company, using industry-standard output profiles that are common in Europe.

Russell Weyant, Straub's production manager, said: "As with the way we unify our own profiles, printing companies must also standardize their own presses. Together with GMG, we have established a proofing system that can The proofs we made in Germany and the United States meet the same standards. The printing conditions we carry out for proofing conform to ISO FOGRA27 standards."

Consistency is not a problem for Straub at all, apart from using relatively expensive inkjet proofs. Weyant said: "We check the machine's calibration every two weeks, but it doesn't change at all."

Straub fully demonstrates the advantages of proofing in accordance with international standards in the global market. Weyant said: “An independent photographer from Costa Rica submitted images with color management profiles embedded in it. We only need to import these images into our system to generate a six-foot-high proof and use it for The first round of signing - all the time needed for this one job will be less than two days. For us, the most important thing is to strive to minimize the amount of work from the camera to the production line. The photographer directly takes the photos from the standardized camera to the Adobe RGB (1998) color space, and then we convert the photos to the ISO CMYK standard and proofing. We call it ' "Open system" because we don't want to know how a specific printer or printer replicates our images."

To match printers accurately with proofs, color management alone is not enough. It also depends on the growth of digital proofing equipment, which includes common Agfa, Canon, Epson, Hewlett-Packard, and Kodak. Other company's inkjet products. Newly formulated pigment inks, multiple substrate choices, faster print speeds, and higher resolutions have made inkjet printers a popular choice for replicating the effects of a press.

Thanks to the use of the standard ICC output profile, one can use color management to create without knowing who will print it.

However, advances in inkjet replication technology have not been the focus of this year's Proofing RoundUP study. In this RoundUP study led by Dr. Abhay Sharma, 25 digital color proofing systems were tested, including inkjet printers and some halftone dot proofing systems. The evaluation of the proofing effect of these equipments was completed during the IPA2005 technical conference held in Chicago. The final report on this research has also been recently completed. It is understood that this report contains all the testing procedures and detailed comparison of the characteristics of these systems, such as: price, speed and cost of each sample.

The IPA Proofing RoundUP performs a series of comprehensive tests on each system, including subjective analysis (visual) of the similarity between each proof and the test sheet printed on the offset press, and for each proof. Objective analysis (colorimetric measurement) to reproduce the accuracy of ECI2002's color management goals. Also included is a subjective and objective analysis of the accuracy of spot color reproduction. The target range of analysis is 11 spot colors and an image printed in colors other than the four CMYK. Members of the research team tested the raster image processor of each proofing device according to the Visual and Technical terms in the Altona Test Suite standard test document to verify their PDF/X-3 compatibility.

The printed form for the IPA test complies with the GRACoL standard, an emerging North American standard for commercial lithographic offset printing (seventh revision has just been completed) that is denser than the dots required by the SWOP standard and has smaller dot gains. This new approach to quantifying replication production will undoubtedly have a significant impact on the high-quality sheetfed printing market.