Direct digital color proofing

In prepress operations, using electronic files instead of film requires the use of the DDCP system, which can generate images directly from digital files. Some systems also interpret digital files as halftone dots. Some systems use different continuous tone or error diffusion techniques to copy proofs to match the color and tone of the final print. If the same RIP is used when producing the film or producing the final printing plate, it is guaranteed that the same dot and other characteristics are obtained on the printed matter. There are also systems that have the ability to control a variety of different resolutions, while also ensuring the matching of colors and obtaining the desired output. Systems with less than 900-1,000 lines of resolution per inch do not faithfully reproduce text and line graphics, but can be faithfully reproduced in print production.

The acceptability of these proofs depends on how well they match the SWOP correction model and whether they can meet the needs of advertising and editing materials. Some proofs have been approved by the design and creative departments of the process, and some have also been printed as proofs.

All DDCP systems must use output curves to simulate ink reproduction on paper. This method can also convert tone reproduction and color to simulate different printing environments. This function better matches printing characteristics than past analog pre-proofing. However, such systems require the user to more carefully maintain the operating environment, calibrate, and deliver files in accordance with the manufacturer's application data sheet.

Special attention should be paid when using other pre-print proofs. The appearance of the direct digital color proof for SWOP should be as close as possible to the SWOP model. This often requires some form of color management while using the instrument to measure the image (objective). Many digital proofing systems can be controlled in this way, and the results are very good. However, these systems all require good color measurement technology and a predictable color management system, and are long-term and reliable.

For the traditional pre-proofing, the manufacturer must provide a standard application data sheet to the SWOP office each time. The degree of matching of these systems with the SWOP models can be obtained using the SWOP calibration kit. The seller is responsible for providing a matching control system, but the user is obliged to continue to maintain this match.

Direct digital color proofs should be accompanied by a description of the seal (such as a label), the proofing product used, the correct document name, identification information, and the name of the person responsible for the production sample. All proofs should also contain a digital proofing control bar provided internally by the manufacturer or the company. The control bar should contain all relevant information about the control bar. The gray balance should be neutral gray and similar to the SWOP proofs, and the print material should also be the same color and brightness as the SWOP proof paper.

Remote proofing

With the implementation of advertising digital delivery, more and more consistent remote proofing systems are needed to optimize the efficiency of this workflow. Samples produced by remote production must be the same as the SWOP proofs used in the current industry. They can be measured and reliable and can be sent together with the film for publication.

Therefore, there is a need for digital control devices that support sample output process control. Such proofing/control systems should include ways to allow the receiving point to duplicate the color and hue information of the proofs. This further emphasizes the need for system calibration and color management.

There are several key issues in controlling this new electronic workflow:

1.
To ensure the consistency and reliability of proofs made from data transmitted from remote addresses. This requires that both the transfer and delivery of test images determine the consistency of the program.

2.
Separate control mechanisms need to be developed to maintain calibration and control equipment that supports remote proofing. This requires independent color management techniques to ensure that production samples can emulate the appearance of SWOP proofs regardless of the equipment and materials used in remote locations.

3.
Application data sheets for color proofing systems applied at remote locations should also list additional issues that will not appear on the local site. For example, self-identification of calibration conditions, automatic inspection of color management profiles, verification of images and control elements, and the like.

In order to ensure these functions are achieved, first of all, control devices and methods such as "color and tone control strips" must be used to evaluate remote proofs and compare their characteristics with the original proofs' characteristic transactions.

It is also possible to use SWOP control devices provided by different digital equipment manufacturers, such as SWOP
Single level color reference for visual (or measurement) comparison.

Obviously, if this kind of workflow is successful, the problem of remote control must be solved.

Digital Proof Control Strip

Digital color scales can be provided by digital proofing manufacturers and can also be generated within the enterprise. All color scales should be met (eg, GATF/SWOP
All requirements for the digital proof control strip and the GAC/GATF digital proof comparison device).