Image forming apparatus

An image forming apparatus, comprising:

• an image forming unit that includes:
• a photosensitive member that rotates;
• a charging unit configured to charge the photosensitive member;
• an exposure unit configured to expose the photosensitive member charged by the charging unit to form an electrostatic latent image on the photosensitive member;
• and
• a developing unit configured to develop the electrostatic latent image on the photosensitive member;
• an image processing unit configured to convert image data based on a plurality of conversion conditions corresponding to a plurality of positions in a predetermined direction orthogonal to a rotation direction of the photosensitive member;
• a reading unit configured to read a pattern image formed on a sheet;
• and
• a controller configured to:
• control the image forming unit to form an image based on the image data converted by the image processing unit;
• control the image forming unit to form a plurality of pattern images including a first pattern image, a second pattern image, and a third pattern image, wherein the first pattern image corresponds to a first tone level, the second pattern image corresponds to a second tone level different from the first tone level, and the third pattern image corresponds to a third tone level different from both of the first tone level and the second tone level;
• control the reading unit to read the plurality of pattern images on the sheet;
• determine respective density profiles for the plurality of pattern images based on a reading result of the plurality of pattern images by the reading unit, wherein the density profiles include data concerning densities corresponding to the plurality of positions in the predetermined direction;
• and
• generate the plurality of conversion conditions based on the density profiles, target density data for each tone level, and a generation condition for each tone level.