Drop placement error reduction in electrostatic printer

A method of printing comprising;

• providing liquid under pressure sufficient to eject liquid jets through a plurality of nozzles of a liquid chamber, the plurality of nozzles being disposed along a nozzle array direction, the plurality of nozzles being arranged into a first group and second group in which the nozzles of the first group and second group are interleaved such that a nozzle of the first group is positioned between adjacent nozzles of the second group and a nozzle of the second group is positioned between adjacent nozzles of the first group;
• providing a drop formation device associated with each of the plurality of nozzles;
• providing input image data;
• providing each of the drop formation devices with a sequence of drop formation waveforms to modulate the liquid jets to selectively cause portions of the liquid jets to break off into streams of one or more print drops and one or more non-print drops in response to the input image data;
• providing a group timing delay device to shift the timing of the drop formation waveforms supplied to the drop formation devices of nozzles of one of the first group or the second group so that the print drops formed from nozzles of the first group and the print drops formed from nozzles of the second group are not aligned relative to each other along the nozzle array direction;
• providing a charging device including:
• a common charge electrode associated with the liquid jets formed from both the nozzles of the first group and the nozzles of the second group;
• and
• a source of varying electrical potential between the charge electrode and the liquid jet, the source of varying electrical potential providing a charging waveform, the charging waveform being independent of the print and non-print drop pattern;
• synchronizing the charging device with the drop formation device and the group timing delay device to produce a print drop charge state on the print drops and to produce a non-print drop charge state on the non-print drops which is substantially different from the print drop charge state;
• providing a deflection device;
• causing drops having the print drop charge state and the non-print drop charge state to travel along different paths using the deflection device;
• providing a catcher;
• and
• intercepting non-print drops using the catcher while allowing print drops to continue to travel along a path toward a receiver.