Ink jet printing having printing control

The printing of an image by a thermal ink jet printer (10) is controlled by a central processing unit (12) based on an internal temperature sensed by temperature sensor (16) of the printer adjacent the printhead (14) and the density of the printed image determined by density determiner 20 in the central processing unit. Prior to printing, the temperature of the printhead is estimated, and the density of the image is determined from stored print data in memory (18) in the central processing unit. Based on the temperature and density, either a single-pass 100% coverage print mode or a double-pass checkerboard print mode is selected. Also, based on the temperature and density, the printhead droplet ejection rate is set. Such control provides a printed image with high quality and prevents misfiring of the ink jets when temperatures and density are high.