A system and processes for the accurate measurement and control of image color values on a printing press with or without the presence of a color bar. More particularly, a universal closed loop color control system and processes for controlling the color quality of color images printed on a substrate online or offline, with or without a color bar printed on the substrate. The system may be run in a “Color Bar Mode” and scan simple rectangular color patches corresponding to each ink key in the print units, or can run in “Gray Spot Mode” and maintain overall target ink density values on the substrate as well as gray balance if the job has critical half tone images, or if the color bar is obtrusive on the job.