The first color difference between the second color space value showing the second color tone and the first color space value showing the first color tone is found when the first color tone is a target of color adjustment and the second color tone is a output of the target, the first color space value is corrected by a predetermined correction amount, the moved ratio of the predetermined correction amount to a moved amount which is derived from the second color space value and the third color space value showing the third color tone is found when the third color tone is a output of the first color space value with the predetermined correction amount, and the color adjustment is conducted based on the first color space value with a amount obtained correcting the first color difference with the moved ratio.