A projector and a mobile terminal are connected wirelessly in two-way communication, and thus the projector is controlled by the mobile terminal. The environmentally friendly acid neutralizing filter cartridge comprises a support housing comprising substantially no metal parts such that the environmentally friendly acid neutralizing filter cartridge can be readily incinerated. The method also includes ordering, over a network connection, the estimated print consumable requirements from a print consumable supplier such that the estimated print consumable requirements are received substantially close to a time that the print job is to be performed. The belt 53 is lubricated with oil injected concentratedly into the belt chamber 63 through jet nozzles 80 disposed in the belt chamber 63.