Patent ID: 7626728

Claim:
A method of evaluating an image forming apparatus, the method comprising the steps of: inputting data associated with spectral reflectances of a plurality of points on a first evaluation chart output from the image forming apparatus by supplying first image data that represents an image having a uniform density in a region to be evaluated in one page to the image forming apparatus to form the first evaluation chart; calculating color differences between a color at a predetermined point and colors at other points on the first evaluation chart based on the data associated with the spectral reflectances on the first evaluation chart; inputting data associated with spectral reflectances of a plurality of points on a second evaluation chart output from the image forming apparatus by supplying second image data that corresponds to a color target for color matching to the image forming apparatus to form the second evaluation chart; calculating color differences between data associated with the spectral reflectances of the plurality of points on the second evaluation chart and data associated with spectral reflectances of the color target, which correspond to the plurality of points on the second evaluation chart; and controlling execution of the second inputting step and the second calculating step so that when the color differences calculated in the first calculating step fall within a permissible range of heterogeneity of colors in the region to be evaluated, the second inputting step and the second calculating step are executed, and when the color differences calculated in the first calculating step fall outside the permissible range, execution of the second inputting step and the second calculating step is skipped.