Patent ID: 8610777

Claim:
A color calibration card for digital photography, which comprises: a printable substrate with a designated front side and a back side, wherein said front side exhibits a maximum of 40 calibration fields which each exhibit a color in a color space according to CIE 1976 (L*, a*, b*) D50 2°, wherein a number of the calibration fields have been selected in such a way that said front side exhibits a first group with at least 3 calibration fields ( 4 G1 , 4 G2 , 4 G3 ) exhibiting respective green colors in said color space having an a value within the range of −30 to −60 and a b value within the range of +10 to +30, a second group with at least 3 calibration fields ( 4 B1 , 4 B2 , 4 B3 ) exhibiting respective blue colors in said color space having an a value within the range of −20 to +20 and a b value within the range of −30 to −60, a third group with at least 3 calibration fields ( 4 R1 , 4 R2 , 4 R3 ) exhibiting respective red colors in said color space having an a value within the range of +40 to +60 and a b value within the range of −5 to +30, and that the respective calibration fields in each group ( 4 G1 , 4 G2 , 4 G3 ; 4 B1 , 4 B2 , 4 B3 ; 4 r1 , 4 R2 , 4 R3 ) exhibit colors for which the values in at least one of the coordinates a or b differ by at least 5 units from the corresponding values for the other calibration fields in the same group, whereby said three green, blue and red colors, respectively, of the calibration fields have been selected in the region where it is expected to find a digital camera's sensitivity peak to the respective color, and with a defined interval between the respective calibration fields in each group, to provide an improved color calibration result by means of said color calibration card in digital photography.