In a method apparatus for measuring the temperature of a semiconductor substrate during processing thereof in a processing chamber, a resonant circuit formed on the substrate surface is energized by an electromagnetic field radiation device, and disturbances in the electromagnetic field are detected to determine the resonant frequency of the resonant circuit. A plurality of printhead modules is mounted to the support beam. A calculation unit selects at least one predefined run length pattern and determines a correction signal based on at least one statistically calculated parameter of the signed deviation value signal for the selected run length pattern. 5 wt % to 10 wt % of a self-dispersed pigment selected from the group consisting of a second polymer-dispersed pigment and a small molecule-dispersed pigment.