A method for halftoning an image, including receiving image data including
a plurality of color separations and comparing image data for first,
second, third, and fourth separations to first, second, third, and fourth
halftone screens. The screens are characterized by first, second, third,
and fourth pairs of frequency vectors, respectively. The fourth pair of
frequency vectors is identical to one of the first, second, and third
pairs of frequency vectors. Further, the first, second, third, and fourth
screens have an associated fill-in sequence, where the fill-in sequence
of the fourth screen is such that overlap between the separation
corresponding to the fourth screen and the separation corresponding to
the one of the first, second, and third screens to which the fourth
screen has an identical pair of frequency vectors does not occur until a
combined dot area coverage of the separations is greater than 100%.