PROBLEM TO BE SOLVED: To properly calibrate the amount of attached toner in an electrophotography that is developed with photoreceptors in an unsaturated state.;SOLUTION: An image forming apparatus comprises: a color conversion processing unit that executes color conversion processing and generates CMYK image data consisting of CMYK gradation values; and a calibration unit that executes first calibration processing of adjusting the developing bias potential of a developing unit within a preset adjustment range, and when the developing bias potential becomes a potential limit value within the adjustment range in the first calibration processing, executes second calibration processing of adjusting a dot area ratio for forming a solid image. The calibration unit estimates the total amount of toner in the CMYK colors in specific pixels that constitute a rear end part in the direction of rotation of a photoreceptor on the basis of the adjusted dot area ratio, and when a total toner amount that is the estimated total amount of toner exceeds a preset toner amount limit value, increases the amount of under color removal in the color conversion processing.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2019,JPO&INPIT
展开▼