These days manufacturers of digital printing systems mostly compare the quality of the output from their systems with offset printing – catchwords are "offset quality" or "offset-similar".

Whereas so far comparisons of various digital printing methods with offset printing were made on a visual basis, System Brunner has now for the first time carried out a metrological evaluation and compared a number of digital printing systems with the industry standard Globalstandard System Brunner® which provides the most precise characterization of standardized offset printing available today.

The analysis and quality rating is mainly done with the Proof Checker, a sophisticated quality control system from System Brunner, with which offset printers can quickly determine whether the print data provided conforms to the defined offset standard and can thus be matched without problems. Here it is immaterial whether the output device works with electrophotographic toner, inkjet cartridges, screen dots or no screen dots.

This makes the Proof Checker solution the world’s first measuring and evaluation system that can not only check offset prints for conformity with the offset standard but proofs and digital prints as well. The system works with the “Proof Zebrastrip” measuring element that can be downloaded free of charge from the System Brunner Website and printed with the job. This is measured in a matter of seconds by a scanning spectrometer. The software analyzes, evaluates and weights more than 50 parameters that influence the color of a picture and rates print quality with a maximum of five stars. High priority is placed on HomogenBalance®.

The evaluation of digital printing systems from Canon, HP Indigo, KonicaMinolta, Kodak, Océ, Xeikon and Xerox showed that some already come close to Eurostandard Offset but all still have weaknesses which lead to distinct visual deviations. It was also shown that the Proof Checker evaluation conforms to the visual impression in the images and is therefore very interesting for digital printing:

• Some manufacturers have meanwhile integrated a metrological control in their digital printing systems which automatically adjusts the results according to certain target values. A cooperation with System Brunner and integration of System Brunner calibration technology could provide them with enormous quality improvements and conformity with the offset standard or special printing conditions.
• Offset printing companies and prepress operations can not only match their proofs to the offset standard but their digital printing machines as well.
• Digital printing companies can objectively check how close their print results come to the offset standard, possibly optimize print output, and use this as a marketing tool. The “Proof Report” quality label verifies the quality achieved and ensures that the customer’s expectations are met.