Patent ID: 8311321

Claim:
A method of predicting the colors of a print produced by a printing press, comprising the steps of: generating a standard density color chart with the printing press which is set to standard density conditions for producing the print of standard densities, and measuring the standard density color chart to determine standard measured values; generating a changed density color chart with the printing press which is set to changed density conditions in which the densities of color materials used to generate the print are individually changed by respective given amounts and the densities of other color materials than the color material with the changed density are fixed to the standard density conditions, and measuring the changed density color chart to determine changed measured values; determining monochromatic standard densities of the standard density color chart which is generated from the color materials; determining monochromatic changed densities of the changed density color chart which is generated from the color materials; and determining corrective standard measured values with respect to standard density setting values for the respective color materials which are set as the standard density conditions, and the differences between the corrective standard measured values and corrective changed measured values with respect to changed density setting values for the respective color materials which are set as the changed density conditions, according to a first relational expression of the corrective standard measured values and the differences which represent the standard measured values with respect to the monochromatic standard densities and a second relational expression of the corrective standard measured values and the differences which represent the changed measured values with respect to the monochromatic changed densities; whereby the colors of the print under desired changed density conditions are predicted using the corrective standard measured values and the differences.