Patent ID: 8472070

Claim:
An image forming apparatus comprising: a formation section configured to form an image on an object which moves relatively thereto in a moving direction; a detection section configured to output a detection signal corresponding to a mark formed on the object by the formation section; a processor; a memory having computer readable instructions stored thereon that, when executed by the processor, causes the processor to perform steps of: first determining at least one of a position of the mark and a density of the mark based on the detection signal; correcting at least one of an image forming position and an image formation density of the formation section based on a determination result by the first determining step; second determining, before the determination by the first determining step, whether a related element which affects the determination result by the first determining step satisfies a set condition which causes an adverse effect on the determination by the first determining step; and controlling the formation section to form a pattern including a mark based on a mark element which is increased when the second determining step determines that the related element satisfies the set condition, compared with that when the second determining step determines that the related element does not satisfy the set condition, the mark element of the mark including at least one of: a width thereof in the moving direction of the object; a width thereof in a direction perpendicular to the moving direction; a density thereof; a distance with an adjacent mark in the pattern; and a number of marks in the pattern.