Ink droplets placement errors of a recording apparatus is to be corrected
with high accuracy. Ink droplets placement errors in a subsidiary
scanning direction of recording head units of a recording head array are
obtained based on a result identified by reading a test chart for
adjusting head alignment for detecting the errors, and it is then
determined as to whether or not the errors identified is in a prescribed
tolerance level (i.e., whether or not the printing result is good). In
the case where it is judged that the printing result is not good,
adjustment of alignment is carried out based on the errors identified.
That is, the ink discharging timing of the recording head units is
controlled per the period of the printing pulses, and the ink discharging
timing of the recording head units is then controlled per the period of
the controlling pulses.