HP RIP Software - HP RIP Software User Guide

4-8 Linearization

Linearization As the density of an image varies from highlights to shadows, or from

lighter tints to darker tints, the printer should accurately reproduce these

areas in a predictable, or linear, fashion. The process of linearization (or

color calibration) involves printing and reading color test patches, and

calibrating the printer to ensure that the expected and printed densities

will match. This in turn will ensure optimal color matching.

You should perform a color calibration when:

• You notice a shift (change) in color output

• Changing ink types or sets

• Changing media types

• Changing print mode (only if the most precise color matching is

required)

Linearization is needed less often with solvent or UV cure inks than with

aqueous inks.

Linearization patches can be read with the printer’s onboard photodiode

or an external spectrophotometer. The RIP supports the following exter-

nal devices:

• X-Rite DTP41 Spectrophotometer (strip reader)

• GretagMacbeth Eye-One Spectrophotometer

For installation instructions, refer to the manufacturer’s user documen-

tation. Before installing the driver software for the GretagMacbeth Eye-

One device, exit from the RIP into Windows. Restart the RIP after the

driver installation is complete.

For calibration instructions, see “Calibrate” on page 3-16.

Note When using a given color profile, dot gain data is saved

with that profile when you perform a linearization/calibra-

tion. If you use a given profile with more than one physical

media (for example, a standard “factory” vinyl profile with

vinyl media from two different manufacturers), be sure

that the last linearization performed was with the media on

which you will be printing. Substandard color quality could

result if the dot gain data from one media is used for print-

ing with a different media.