Tandem image forming apparatus

An image forming apparatus that includes a plurality of image-forming process cartridges arranged in tandem, comprising:

• a color-information acquiring unit configured to acquire color information representing a color of an image to be formed by each of the image-forming process cartridges;
• an image-information distributing unit configured to distribute print information for the color to an image-forming process cartridge that forms an image of the color;
• a designating unit configured to designate a print mode that includes a monochromatic mode and a full-color mode;
• a control unit configured to control image forming operation by the image-forming process cartridges to perform a print operation in designated print mode;
• and
• an alarming unit configured to generate an alarm in response to the full-color mode being designated by the designating unit when the color is identical in two or more image-forming process cartridges.