Background detection and compensation

摘要

A method adjusting toner concentration in a printing machine by first reading a first clean imaging surface reflectance value from a segment of the imaging surface with the developer in an off mode and storing the reflectance value as a reference. A second clean imaging surface reflectance value from the same segment of the imaging surface is then read with the developer in an on mode. The first clean imaging surface reflectance value is compared to the second clean imaging surface reflectance value and the toner dispenser is controlled in response to the difference.