Patent ID: 8149480

Claim:
An image forming apparatus that has a plurality of calibration modes set in advance on a time-zone-by-time-zone basis for operating days, the image forming apparatus comprising: a day-of-week/time-of-day determining unit that determines a present day of week and a present time of day; a storing unit that stores use frequency data of said image forming apparatus on an hour-by-hour and day-of-week basis; a selection unit that reads out, from said storing unit, the use frequency data corresponding to the present day of week and the present time of day determined by said day-of-week/time-of-day determining unit, and selects one of the calibration modes based on the read-out use frequency data; a counting unit that performs cumulative counting of sheets subjected to color printing after a preceding calibration; a calibration-execution determining unit that determines whether or not calibration in the calibration mode selected by said selection unit should be executed, from a cumulative count value of sheets subjected to color printing counted by said counting unit and the calibration mode selected by said selection unit; and a calibration execution unit that executes the calibration in the calibration mode selected by said selection unit, in response to the determination by said calibration-execution determining unit that the calibration should be executed.