A color chart having a plurality of mirror-image color blocks arranged in a matrix, with each color block a mirror image of an adjacent color block, each color block having rows and columns of color patches, wherein the concentration of a first color of the multiple colors changes unidirectionally across color patches in any given row of a color block, the concentration of a second color of the multiple colors changes unidirectionally across color patches in any given column of a color block, and the concentration of a third color of the multiple colors remains unchanged across all the plurality of color patches within a color block and differs only between color blocks.