The color of magenta using newly developed magenta ink has characteristics L*≅41, a*≅82, and b*≅24, and has differences ΔL*≅4, Δa*≅0, and Δb*≅26 from the conventional magenta ink, i.e., the lightness value is low, and the color difference b* assumes a very small value. When the color of red is reproduced using such new magenta ink, its lightness and saturation values are low, and subdued red is reproduced, i.e., a visually favorable color cannot be obtained. Hence, when a color included in a first color gamut is input, and the input color is converted into the color of a second color gamut narrower than the first color gamut, color conversion is made using a three-dimensional lookup table having red defined by. L*≅45 to 50, a*≅67 to 70, and b*≅50 to 55.