Utilization of non-printing high-spatial-frequency auxiliary pixels are
introduced into the bitmap of an image to obtain local control of the image development
by modification of local average voltage in the development nip. These auxiliary
pixels embody frequencies or levels of charge that are past the threshold for printing
on the Modulation Transfer Function (MTF) curve, and therefore by themselves result
in no toner deposition on the resultant page. These auxiliary pixels will however,
position the toner cloud by modulating it and to compensate for cleaning field
and toner supply effects. This will better position the toner cloud to ensure adequate
toner supply to all parts of the image so that the desired printing pixels will
print as intended.
