Global press controls provider QuadTech and graphic software provider Alwan Color Expertise (Lyon, France) have joined forces to provide on-the-fly automated plate curve monitoring and adjustment for web offset press applications. Working with QuadTech's Color Control System with SpectralCam, Alwan's PRINT Standardizer software automatically compensates for dot gain deviations in virtually all printing situations and also provides ISO 12647 and G7 compliance confirmation.
The software relies on measurement data provided by QuadTech's Color Control System with SpectralCam. The spectral data is converted to L*a*b* and densitometric values including dot gain or tonal value increase (TVI). Analysis by the Alwan software determines any dot gain variations and can automatically generate dot gain compensation curves, per job or over a specified time period. Alwan PRINT Standardizer monitors and stores data from any number of presses or papers per press. This information is easily retrieved, using parameters such as job, press, or paper name. The result is simpler, faster make-ready times, and greater stability from job to job. The combined solution is easily integrated into any existing workflow.
"Many factors can lead to dot gain variations on a press," according to Elie Khoury, president of Alwan. "These include paper, ink set, damping solution, room conditions (temperature and humidity), printed form content, and mechanical properties of the press. Maintaining constant control over dot gain is essential because increases of even three percent can result in color changes detectable to the human eye."
Any commercial printer can now achieve the same quality output from their web-fed as their sheet-fed press due to the collaboration of QuadTech and Alwan technology. Without the Alwan and QuadTech combined solution, dot gain shows a lot of deviation and is very unpredictable. With the new automated in-line measurement and standardizing technology, web printers can achieve print consistency and dramatically decrease make-ready time.
Greg Wuenstel, QuadTech product manager, comments: "Because of the diversity of substrates, not to mention the many factors that can cause deviation, monitoring and optimizing dot gain compensation curves has traditionally been a labor intensive task. Alwan's PRINT Standardizer software, together with QuadTech's color control technology, provides a fast, reliable means of ensuring consistent, ISO-compliant quality in web-offset, in virtually any printing situation."