Introduction 1-8
CADJET
®
3D User Guide
7. RIP Diffusion/Dither Patterns
Images that are going to be printed on an inkjet printer are eventually divided into C, M, Y,
K and rasterized into dots using patterns that cause the eye to see a continuous tone
image. These patterns are called many things, such as frequency modulated screening,
diffusion patterns, dither patterns, screen patterns, etc. There are various types of screen-
ing that are better for photographic images. Stochastic screening was developed specifi-
cally for the CMYK process to avoid the problem of visually perceptible banding that
occurs with other pattern types. It does this by pseudo-random placement of dots. Varia-
tions of the stochastic strategy have evolved into even better patterns. Each RIP manufac-
turer uses different names to describe its particular variation on the stochastic theme. To
get the best print quality, make sure you are using the best possible diffusion pattern
available from the RIP software you are using. Also remember that a different diffusion
pattern should be used for spot color objects (such as filled vector objects). If you are
printing an image that contains both photographs and spot color objects, use the diffusion
pattern designed for photos.
8. Ink and Media
Using the right ink and media is a much bigger factor in print quality than most inkjet
users realize. It takes many months of using a printer before a user begins to understand
what an exceptional print looks like. Then and only then can they fully appreciate what
quality materials and inks can do. Inks must be developed specifically for a particular
head, otherwise, cartridge reliability will be severely reduced. ENCAD inks are specifi-
cally developed for ENCAD cartridges, printers, and media. These inks create the perfect
ink drop shape, trajectory, and landing shape when used with ENCAD cartridges. The
media controls the color, dot gain, and durability of the final print. As the ink must
chemically interact with the media, only medias developed specifically for a particular
ink can achieve the perfect dot shape that leads to improved image quality. Additionally,
the chemical bond created through co-developed inks and medias is much better than
independently developed inks and medias. Although many people will not be able to
visually perceive differences in quality inks and medias initially (poor inks and medias
show more pronounced visual defects), a less-than-optimal image quality, image color, or
image durability will likely develop over time. Chemical compatibility between inks
(made for a specific head technology) and medias is a key, and often overlooked ingredi-
ent to print quality.