The pulse energy applied to the droplet generating means of an ink drop printhead is modified in accordance with the time for which the printhead has been out of use. Thus, as shown in Fig 2, the areas designated 2 represent the beginnings of new lines which are predisposed to receive insufficient ink. The present invention is stated to compensate for this in accordance with the time between cessation of the previous print line and the commencement of the new print line. <IMAGE>
