Abstract: Disclosed is a new printing apparatus and process for inkjet printers which incorporates spectral modeling of ink mixing and the technology of halftoning in device-independent color space. In addition no colormap building or color mapping processing is necessary, because color correction is conducted in device-independent space and is built into the halftoning process. also disclosed is an automatic self-calibration by the printer without user intervention or user preferences by using an optical sensing unit on the printer. The procedure corrects for print cartridge to print cartridge variance, and variance of print cartridges over time and also provides for faster processing of color images.