Colors similar to those which would be used in calibrating a target
printer are printed on a printer of the same model and with the same
materials set as anticipated for the printer calibration. These all lie
within a substantially reduced portion of the gamuts of both the printer
and scanner. A scanner characterization is derived only for those
portions of color space corresponding to the printed colors. This may be
done using spline fitting in one or more dimensions. While generic
scanner calibrations generally have errors in excess of .DELTA.E=7, with
these techniques values generally less than 1.7 were obtained. This is
sufficient for printer calibration.