The present invention provides an image forming apparatus that can perform stable sheet conveyance, regardless of whether a sheet processing apparatus is connected thereto. The present invention further provides for pharmaceutical compositions, medicaments, and kits useful in carrying out these methods. Object distortions and ghosting caused by image parallax when generating the image mosaics are then minimized by blending pixel colors, or grey values, for each computed depth to create a common composite area for each of the overlapping images.