A method of converting a source image representing a reference image to a digital representation of a preferred image, in which subject-dependent adjustments are made to chroma in various parts of said image when converting from a larger color space to a smaller color space or from a smaller color space to a larger color space, wherein said source image comprises pixels rendered in a first color space and said representation of said preferred image is rendered in an extended gamut color space obtainable with a colorant set comprising cyan, magenta, yellow and at least one redundant color other than black, the method comprising the steps of: a) determining source values of lightness, chroma, and hue for each of the pixels in the source image; b) assigning to each of the pixels a preferred chroma value according to a preselected chroma expansion function defining a percentage of an additional available chroma value, not resulting in a change in lightness or hue, to be assigned to each of the pixels, the chroma expansion function being dependent upon the source lightness value, the source chroma value, or the source hue value, said preferred chroma value being within the extended gamut color space at said source lightness value and said source hue value, wherein the preferred chroma value comprises the source chroma value plus the percentage of the additional available chroma value defined by the chroma expansion function, the maximum preferred chroma value, corresponding to the source chroma value plus 100% of the additional available chroma value, being the absolute maximum chroma value that can be produced with the colorant set with the lightness and hue values of the digital representation of the preferred image remaining the same than the lightness and hue values of the source image; and c) storing the digital representation of the preferred image on a computer readable medium in the form of computer readable code, wherein the digital representation of the preferred image represents for each pixel the source lightness value, the source hue value, and the preferred chroma value. a) determining source values of lightness, chroma, and hue for each of the pixels in the source image; b) assigning to each of the pixels a preferred chroma value according to a preselected chroma expansion function defining a percentage of an additional available chroma value, not resulting in a change in lightness or hue, to be assigned to each of the pixels, the chroma expansion function being dependent upon the source lightness value, the source chroma value, or the source hue value, said preferred chroma value being within the extended gamut color space at said source lightness value and said source hue value, wherein the preferred chroma value comprises the source chroma value plus the percentage of the additional available chroma value defined by the chroma expansion function, the maximum preferred chroma value, corresponding to the source chroma value plus 100% of the additional available chroma value, being the absolute maximum chroma value that can be produced with the colorant set with the lightness and hue values of the digital representation of the preferred image remaining the same than the lightness and hue values of the source image; and c) storing the digital representation of the preferred image on a computer readable medium in the form of computer readable code, wherein the digital representation of the preferred image represents for each pixel the source lightness value, the source hue value, and the preferred chroma value.