Coldset printers often use gray-balance fields for the adjustmentand control of ink quantity during print runs. This method helpsthe printer to significantly reduce unwanted color cast in the printedproduct. A common way in sheet-fed offset to control the amount of inkis to decide upon target tone-value increase (TVI/dot gain) or densitylevels, with the intention to print the best subjective quality, even thoughthe same quality cannot always be attained in every print run. Today, apredictable and equal quality is generally desirable, and therefore calibrationand standardization are more in focus. Since there is no standardizedway to calibrate a sheet-fed offset press, the possibility to producean equal print quality in different print runs and printing presses islimited.Gray-balance control is a way to calibrate printing presses. The presseswill always be set to print one standardized combination of CMYhalftones in the same way. Hopefully, this will create a similarity betweenprint runs, presses and to some extent paper qualities, which gives thefoundation for robust ICC profiles.Astudy including print runs, evaluation of prints and creation of ICC profileshas been carried out. The use of gray-balance control in sheet-fed offsetwas primarily explored. It turned out to be possible to print without acolor cast, and still keep print contrast, density, dot gain and CIELAB valuesfor the secondary colors at an acceptable level. Prints on differentcoated papers were compared to investigate the similarities between thesesamples, when using this method and ICC profiles. The study showedthat an ICC profile can give a similar print quality on different papers.
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