Image forming apparatus

An image forming apparatus comprising a plurality of image forming units configured to form a developer image,

• wherein each of the plurality of image forming units includes:
• an image bearing member on which a latent image is able to be formed;
• a charging device configured to charge the image bearing member;
• a developing device configured to develop the latent image into a developer image;
• and
• a transfer device configured to transfer the developer image from the image bearing member to a transfer member,
• wherein in a predetermined image forming unit A and image forming unit B among the plurality of image forming units, a common transfer voltage is applied to the respective transfer devices from a common transfer power supply and charging voltages are applied to the respective charging devices from different charging power supplies,
• wherein the image forming apparatus further comprises:
• an exposure device configured to expose the image bearing members charged by the charging devices to form the latent images on the image bearing members;
• and
• a control unit configured to, in either one or both of the image forming units A and B, adjust an amount of exposure by which the image bearing member is exposed and the charging voltage based on information about the image bearing members of the image forming units A and B, and
• wherein the control unit is configured to make the charging voltage and the amount of exposure in the image forming unit A different from the charging voltage and the amount of exposure in the image forming unit B.