About halftone screen frequency – Adobe Acrobat 8 3D User Manual
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ADOBE ACROBAT 3D VERSION 8
User Guide
Apply Output Preview Settings
Simulates the print space defined by the device identified in the Simulation Profile
menu of the Output Preview dialog box (choose Advanced > Print Production > Output Preview). This option allows
you to simulate the appearance of one device on another.
Simulate Overprinting
Simulates the effects of overprinting spot inks in composite output and converts spot colors
to process colors for printing; the document itself is unchanged. This option is useful for printing devices that don’t
support overprinting and is available only if you choose Composite from the Color menu. If you intend to use a file
for separations on a RIP (raster image processor) or for final output, don’t select this option.
Important: When printing to a printer that supports overprinting, make sure that this option is unselected, so the
printer’s native overprinting capabilities are used.
Transparency Flattener Preset
Flattens transparent objects according to the preset you choose.
Use Maximum Available JPEG2000 Image Resolution
Controls how resolution progression information, if present,
is used when generating PostScript. When selected, the maximum resolution data contained in the image is used.
When unselected, the resolution data is consistent with the resolution settings on the Transparency Flattening panel.
Ink Manager
Modifies the way inks are treated while the current PDF is open.
See also
“Ink Manager overview” on page 476
About halftone screen frequency
In commercial printing, continuous tone is simulated by dots (called halftone dots) printed in rows (called lines or
line screens). Lines are printed at different angles to make the rows less noticeable. The Screening menu in the Output
section of the Print dialog box displays the recommended sets of line screens in lines per inch (lpi), and resolution
in dots per inch (dpi), based on the currently selected PPD. As you select inks in the ink list, the values in the
Frequency and Angle boxes change, showing you the halftone screen frequency and angle for that ink.
A high line-screen ruling (for example, 150 lpi) spaces the dots closely together to create a finely rendered image on
the press; a low line-screen ruling (60 lpi to 85 lpi) spaces the dots farther apart to create a coarser image. The size of
the dots is also determined by the line screen. A high line-screen ruling uses small dots; a low line-screen ruling uses
large dots. The most important factor in choosing a line-screen ruling is the type of printing press your job will use.
Ask your service provider how fine a line screen its press can hold, and make your choices accordingly.
B
D
A
C
Line screens
A. 65 lpi: Coarse screen for printing newsletters and grocery coupons B. 85 lpi: Average screen for printing newspapers C. 133 lpi: High-quality
screen for printing four-color magazines D. 177 lpi: Very fine screen for printing annual reports and images in art books