Photo Art & Contone - Konica Minolta magicolor 2550 Series Technical Manual

Traditional Halftone Cell: 1 bit/pixel
1 bit/pixel means that each dot can be
only one size—the laser beam is either
"on" or "off" (white) Therefore, there are
only 2 possible gray or color levels.
Contone Halftone Cell: 4 bits/pixel
4 bits/pixel means that each dot can be 1
of 15 different sizes or "off" (white).
Therefore, there are 16 possible gray or
color levels.
Photo ART screening produces great
color detail and results in more gray or
color levels than conventional screening.
Photo ART screening produces smooth
gradients.
Photo ART and Contone
By using 9600 x 600 dpi-class with Photo ART contone screening, the
magicolor 2550 Series printers generate photorealistic output with great
detail and character in the fine lines and halftones.
When printing at 600 x 600 dpi, the magicolor 2550 Series printers (and
other 600 x 600 dpi printers) have only two options for controlling the
laser beam (which is responsible for telling the print engine how much
and what color toner to place on the media). They can either turn the
laser beam "on" (place toner on the media) or "off" (do not place toner
on the media)—600 times per inch. And because the laser beam can be
only on or off, each printed dot has the exact same size. This is equal to
1 bit (2 gray or color levels) per pixel, and this resolution is called
"Standard" in the magicolor 2550 EN and 2550 DN printer drivers.
In contrast, when printing at 9600 x 600 dpi-class resolution (called
"High Quality" in the printer driver), the magicolor 2550 EN and 2550
DN employ pulse width modulation (or PWM) to control the length of
time the laser beam remains "on" to create each dot, consequently
controlling the size of the dot. Fifteen different dot sizes as well as "off"
(do not place toner on the media) are possible. This is equal to 4 bits
(16 gray or color levels) per pixel rather than only 1 bit (2 levels) per
pixel, and it produces an incredible 4096 colors per dot. The result is
the type of high-quality output—with even fill patterns, a wide variety of
hues and shades, better detail, and more accurate colors—that can
usually be produced only by professional print shops.
Print quality is further enhanced by dithering (varying the pattern of the
dots) and KONICA MINOLTA Simitri Polymerized Toner technology.
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