Patent ID: 7843601

Claim:
A method for forming a color image in a color image forming device comprising a plurality of feeders of print media, an image producing unit, and a test pattern sensor, the method forming a test pattern on a print medium and adjusting color balance of the image producing unit based on chromaticity of the test pattern detected by the test pattern sensor, the method comprising: selecting a feeder of print media for subsequent printing, the feeder including a duplex printing unit; determining whether any one of the feeders of print media is selected before first feeding operation and in advance in the selecting and whether the feeder of print media selected before first feeding operation and in advance is the duplex printing unit; adjusting the color balance of the image producing unit by forming the test pattern on a print medium fed from the selected feeder if it is determined that any one of the feeders of print media, which is not the duplex printing unit, is selected before first feeding operation and in advance in the selecting, wherein, when the image of the test pattern is formed, if it is determined that any one of the feeders of print media is not selected, a test pattern is formed on a print media fed from the feeder of print media stored when a most recent image is formed, and the color balance of the image producing unit is adjusted, and if it is determined that the duplex printing unit is selected as any one of the feeders of print media before first feeding operation and in advance in the selecting, a test pattern is formed on a print medium fed not from the duplex printing unit but from another feeder from which a print media is conveyed into the duplex printing unit for first-side printing, and the color balance of the image producing unit is adjusted; and storing, in a memory unit, as a history, a feeder that feeds the print media, when the image of the test pattern is formed.