Oki ES3640e MFP, Руководство по цветам

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1-7 Managing colour on the ES3640e MFP
Black Overprint
The Black Overprint option allows you to specify whether or not black text or
text/graphics—defined as RGB = 0, 0, 0, or as CMYK = 0%, 0%, 0%, 100%—
overprints coloured backgrounds.
•
Text
—Black text overprints coloured backgrounds, eliminating white gaps and
reducing halo effects or misregistration of colours.
•
Text & Graphics
—Black text and graphics overprint coloured backgrounds,
eliminating white gaps and reducing halo effects or misregistration of colours.
•
Off
—Black text or text/graphics knocks out coloured backgrounds.
N
OTE
:
PostScript applications may perform their own black overprint conversions
before sending the print job to the ES3640e MFP.
One example of how you might use this setting is with a page that contains black text
on a light blue background. The background blue colour is CMYK = 40%, 30%, 0%,
0% and the black text is CMYK = 0%, 0%, 0%, 100%.
• With Black Overprint set to Text or Text & Graphics, the final text or text/graphic
portions of the page are overprinted, or combined with the underlying colours.
Black colours generated by applications (for example, RGB = 0%, 0%, 0%; CMYK
= 0%, 0%, 0%, 100%) are printed using the maximum amount of black toner
allowed by the calibration curve. This means that black text and line art will not
exhibit halftone artifacts (as long as the printer is calibrated correctly). There is no
transition in the cyan and magenta toners, and the quality of the output is improved
since it will not show artifacts near the edges of the text or text/graphics. The option
also works with text defined in the RGB colour space, that is RGB = 0, 0, 0.
• With Black Overprint Off, the border of the text or text/graphics is on an edge that
has cyan and magenta toners on one side (outside the text) and black toner on the
other side (inside the text). This transition may cause visible artifacts because of the
practical limitations of the printer.