Abstract: An image forming apparatus includes a plurality of image bearing members bearing latent images, image forming units for forming the latent images on the image bearing members, developing units for developing the latent images on the image bearing members, a transport belt for transporting a transfer member on which images of different colors developed by the developing units are successively transferred as the transfer member is transported, and image pickup elements, arranged obliquely to a main scan direction of the image forming units and located on a downstream of a most downstream one of the image bearing members along a direction in which the transport belt transports the transfer member. The image pickup elements detect as image information transmitted or reflected light quantity distributions of regions which include marks transferred on the transport belt from the image bearing members.

Abstract: When a time mode is selected, after power to the apparatus as a whole is cut off, the time until the scheduled start of supply of power to the heating units is counted. When the scheduled time of the start of supply of power is reached, power starts to be supplied to the heating units. When the continuous mode is selected, instruction is given to continue supplying power to the heating units even when power to the apparatus as a whole is turned off.

Abstract: In a printing system in which printing is conducted on sheets of cut paper supplied from a sheet hopper and the printed sheets are stacked in a stack unit, the binding apparatus binds a bundle of sheets of printed cut paper discharged to the stack unit, wherein the binding apparatus includes: a conveyance arm that holds an end portion of the bundle of printed cut paper in a vertical direction and conveys them in a horizontal direction; a binding machine that binds the bundle of sheets of cut paper conveyed by the conveyance arm with a band-shaped or string-shaped binding medium; an output unit that stocks and outputs the bundle of sheets that have been bound; and a control unit that controls the conveyance arm, binding machine and output unit.