The present invention relates to an image forming apparatus including an image forming unit that forms a color image in which a plurality of color component images are superimposed; and a formation controlling unit that allows the image forming unit to form images for adjustment of formation positions of the color component images, and a method of adjusting a color shift in the image forming apparatus.
In image forming apparatuses capable of forming color images, such as copiers and multifunction devices, a color image is formed by superimposing color component images of C (cyan), M (magenta), Y (yellow), and K (black), for example. To maintain good image quality of a color image, it is important to minimize the shift in the formation position of each color component image, which is caused by an influence of periodic speed variations of photosensitive bodies or the like. Hence, marks for adjustment of color component images of C, M, Y, and K are formed, the presence/absence of a color shift in the color component images is checked, and if there is a color shift, then a formation position is corrected (see Japanese Patent Application Laid-Open No. 2002-207338, for example).