Image forming apparatus and image forming method

An image forming method performed by an image forming apparatus comprising:

• a recording head having aligned in a secondary scanning direction a plurality of dot forming sections each of which is a component for forming a dot on a recording medium;
• primary scanning portion for moving the recording head relative to the recording medium in a primary scanning direction intersecting the secondary scanning direction;
• and secondary scanning portion for moving the recording head relative to the recording medium in the secondary scanning direction,
• wherein the recording head is moved relative to the recording medium by means of the primary scanning portion and the secondary scanning portion so as to form, on the recording medium, a subject image which is a predetermined image, the image forming method comprising:
• first instruction step of instructing the recording head, the primary scanning portion, and the secondary scanning portion to form the subject image of a first resolution which is previously set;
• and
• second instruction step of instructing the recording head, the primary scanning portion, and the secondary scanning portion to form, in an area other than an area in which the subject image on the recording medium is formed, a test pattern of a second resolution which is previously set and is different from the first resolution.