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Using application-defined halftones
If your site has installed the Graphic Arts Package (not available for all Color Server models),
you can define halftones from several PostScript applications and use them when printing.
The results may vary, depending on the application.
To define a halftone, use the application to adjust the Frequency and Angle values of the
halftone. When you print the job, choose Application Defined for the halftone screen print
option.
The Frequency and Angle settings in the Application Defined halftone are used regardless of
whether the setting for Combine Separations is set to On or Off. For special instructions on
printing separations with Photoshop, see
“Selecting options when printing”
on page 34.
N
OTE
:
In general, using halftones is not recommended, because the printed output will have
visible dots of toner, rather than smooth blends. Use halftones only when necessary to achieve
a specific style of printed output.
Ensuring color accuracy when you save a file
To ensure color accuracy, take the following steps:
• When saving CMYK EPS files, do not include PostScript color management information.
This minimizes the risk of conflicting data and multiple color conversions. PostScript
color management causes your CMYK colors to be interpreted by the Color Server as
though they were supplied in the Lab color space and, as a result, processed by RGB print
options, rather than your CMYK Source and CMYK Processing Method settings.
• Include ICC color information in files. ColorWise does not conflict with this information,
and such data is useful for identifying the specific color space used by your files.
• Do not include halftone and transfer functions.
• Turn off color management in the printer driver.
On Windows computers, on the Color Management tab of the printer’s Properties, make
sure that no color profiles are associated with the printer.
On Mac OS computers, in the ColorSync settings of the printer driver, set the Color
Conversion option to In Printer and the Quartz Filter option to None.
