Location information representing the location of a defective pixel in an image pickup device and pixel defect level information representing the pixel defect level of the defective pixel are stored beforehand in a memory. The defect level of the defective pixel is determined after shipment of the image pickup device, and the pixel defect information is updated based on the defect determination result. If a new defective pixel is detected at a location different from the location of the defective pixel with the pixel defect information stored in the memory, the pixel defect information of that defective pixel is added. If a defective pixel is detected at the same location as the defective pixel with the pixel defect information stored in the memory, and if the defect level of the detected defective pixel is worse than the original defect level, the defect level of the defective pixel is updated.