1. An image forming apparatus comprising: an image holding component for holding an image; a first image forming device for forming a first image on a surface of the image holding component; a second image forming device for forming a second image on the surface of the image holding component; a switching unit for switching a mode between a first mode and a second mode, the first mode being where the first image forming device and the second image forming device come into contact with the image holding component and the second mode being where the second image forming device and the image holding component do not come into contact and the first image forming device comes into contact with the image holding component; a detecting unit for detecting information concerning an image formed on the surface of the image holding component in relation to switching from the second mode to the first mode; and a modifying unit for modifying at least one of an image forming condition for the first image and an image forming condition for the second image, in accordance with the information detected by the detecting unit.