Contract Proofing

Most printing companies and their customers still like to use a colour-accurate, contract-quality hard proof as a final reference for the press run. Customers can sign their names onto something physical that also provides a contractual obligation to pay for a job if it matches the proof.

The market is no longer dominated by proprietary hardware proofing systems that are tied to very specific software solutions. Instead, today’s proofing alternatives redefine the view of “system” as an integration of best-in-practice components. The result is proofing systems with dramatically lowered purchase and operating costs that can simultaneously improve proofs’ accuracy and output speed.

Most new generation proofing systems also have open architectures, which means they have more flexibility and control. Because individual components are easily changed or upgraded, much of the original equipment investment is preserved as well as the time and effort to install, learn and implement the system — a significant portion of the real total system cost.

What has helped drive the adoption of open architecture systems are recent technological advances in inkjet printers. These devices’ colour gamuts are large enough to address the colour space printable by most offset presses. With proper software and operation, their colour accuracy and repeatability are excellent. Fading and colour shifts have been dramatically reduced; results are less influenced by environmental conditions.

Another factor is the need for remote proofing. If you are working with publishers or many national accounts, you are probably using, or at least considering, remote proofing systems. They save the time and cost of shipping hard proof overnight to another office—or, most likely, to a handful of remote offices. The approval process is very often a collaborative one. With many remote sites, the objective of achieving the most consistency between multiple remote systems becomes a much more challenging process.

To achieve this, there must be a common reference standard. The ICC process takes the printer profile, combines it with the inkjet proofer profile and calculates 'conversion factors' - a way of comparing colour output differences between the printer and the inkjet proofer.

The ICC concept still makes sense, especially when it comes to calibrating RGB scanners and monitors. However, there are major limitations with regards to contract-quality digital proofs. A device link approach offers a solution that does better justice to the high demands of a contract proof while retaining compatibility to existing ICC profiles and practices.

GMG ColorProof is the most accurate way of calibrating a digital inkjet proofing engine to produce digital contract colour proofs, precisely colour-matched to the actual printing press.

By utilising advanced algorithms and a unique 4D colour transformation engine, GMG ColorProof permits more accurate colour matching than any other application in the industry and has become the de-facto standard in many print industry sectors. The application is unique in that it calibrates the entire mechanical colour gamut of the inkjet engine it drives, not just the CMYK. The system consists of the ColorProof basic software, which includes colour engine, profile editor and RIP, and output modules for various printing devices. To calibrate the system all standard colour targets can be automatically measured, using a colorimeter. Device-independent colour profiles can be stored device-independent, which makes the system, together with some very sophisticated linearisation tools, highly suitable for remote-proofing applications.

GMG ColorProof supports all usual spot colour systems up to 64 individual colour channels, includes an ICC engine for colour compatibility, and simulates dot gain and paper tint. The GMG ColorProof system features various workflow capabilities, and allows the use of a whole range of different formats, including TIFF-IT, PostScript, and PDF up to level 1.3. GMG ColorServer allows additionally e.g. the conversion of one CMYK colour space to another, whilst keeping the integrity of the black channel. Offset data can for instance be automatically converted to gravure data.

Hi-Fi Colour, Pantone, Hexachrome and spot colours can be easily and reliably proofed.

The GMG DotProof option takes the 1-bit TIFF information generated by the output RIP and transforms the color whilst retaining the original screening information. Depending on the printer make and model, even very fine screening resolutions are possible. By retaining the original screening information DotProof enables users to check for possible moirés and trapping errors, for example, only visible with screened data. DotProof is an important option, particularly for CTP workflows, where problems can be identified before final plate production with resultant savings in material and time, particularly important in time-critical applications like newspaper publishing.