1. An image processing method for performing color conversion among a plurality of image forming apparatuses, comprising the steps of: a) producing a plurality of color profiles provided for performing color conversion on input image information within a same color space or through different color spaces; and b) selecting one of said plurality of color profiles whereby color in an image formed by one of said plurality of image forming apparatuses may be made effectively approximate color of an image formed by another of said plurality of image forming apparatuses.