Color printing

A method of operating a color printer comprising:

• transforming input color print data to printer color space primary colors using a predetermined conversion color table, the printer color space primary colors including non-black primary colors;
• if the printer is operating in a first resolution mode, then adjusting the non-black primary color values associated with the printer color space primary colors using a first color table with contributions from a first one-dimensional gray balancing related primary color TRC, a first one-dimensional primary component related primary color TRC, and a first one-dimensional secondary component related primary color TRC;
• if the printer is operating in a second resolution mode, then adjusting non-black primary color values associated with the printer color space primary colors using a second color table with contributions from a second one-dimensional gray balancing related primary color TRC, a second one-dimensional primary component related primary color TRC, and a second one-dimensional secondary component related primary color TRC;
• whereby the same conversion color table is employed when the printer is operating in the first resolution mode and the second resolution mode, accordingly;
• and
• a color output produced using the second color table in the second resolution mode substantially colorimetrically matches a color output produced in the first resolution mode, wherein:
• adjusting the non-black primary color values using the first color table comprises:
• for each non-black primary color value, determining an amount of a respective gray component that contributes to a gray color, an amount of a respective secondary color component that contributes to a secondary color, and an amount of a respective primary component that does not contribute to the gray color or the secondary color;
• for each non-black primary color value, determining a respective gray contribution by scaling an index value of a respective gray balancing related one-dimensional look-up table with the respective gray component, wherein the respective non-black primary color value is used to index the respective gray balancing related one-dimensional look-up table;
• for each non-black primary color value, determining a respective secondary color contribution by scaling an index value of a respective one-dimensional secondary color related look-up table with the respective secondary color component, wherein the respective nonblack primary color value is used to index the respective one-dimensional secondary color related look-up table;
• for each non-black primary color value, determining a respective primary color contribution by scaling an index value of a respective one-dimensional primary component related look-up table with the primary component, wherein the respective non-black primary color value is used to index the respective one-dimensional primary component related look-up table;
• and
• summing the respective gray contribution, secondary color contribution, and primary contribution for each non-black primary color to obtain adjusted non-black primary color values.