In-RIP trapping settings
In-RIP trapping allows you to specify advanced trapping settings. Before selecting In-RIP trapping, ensure that your PostScript 3 printer supports In-RIP trapping options.
You can select a trap width — the amount that one color spreads into another. You can also specify image trap placement, which determines where the trap occurs. You can, for example, specify whether the trap is a choke or a spread, depending upon the neutral densities of adjacent colors. Neutral density indicates the lightness or darkness of a color and helps determine how adjacent colors spread into one another.
You can specify a threshold at which a trap is created by specifying a step trap limit. If trap colors are of similar neutral densities, the trap placement adjusts accordingly. The step trap limit specifies a threshold at which a trap adjusts.
Before trapping, you can set the inks; for example, you can set an ink to opaque, as in the case of a metallic ink, so that nothing shows through it. To reduce the visibility of a trap, you can decrease the amount of ink color in a trap. This is especially helpful in the case of pastel colors, contrasting colors, and colors with similar neutral densities.
To select a trap width
1
Click
File Print.
3
Enable the
Composite option.
4
Click the
PostScript tab.
5
Choose
PostScript 3 from the
Compatibility list box.
6
Click the
Composite tab.
7
Enable the
PostScript level 3 In-RIP trapping check box.
9
Type a value in the
Trap width box.
If you are trapping to black, type a value in the
Black trap width box.
To select In-RIP trapping options, you must have selected PostScript 3 from the Compatibility list box under the PostScript tab of the Print dialog box.
To specify image trap placement
1
Click
File Print.
3
Enable the
Composite option.
4
Click the
PostScript tab.
5
Choose
PostScript 3 from the
Compatibility list box.
6
Click the
Composite tab.
7
Enable the
PostScript Level 3 In-RIP trapping check box.
9
From the
Image trap placement list box, choose one of the following placements:
•
Neutral density — used to determine the lighter object and thus the direction and placement of the trap
•
Choke — used to trap a dark foreground object to a light background image
•
Spread — used to trap a light foreground object to a dark background image
•
Centerline — used when adjacent images and objects have similar neutral densities or when image density changes along an object’s edge
If you want to trap an object to an image, enable the
Trap objects to images check box.
To specify a threshold
1
Click
File Print.
3
Enable the
Composite option.
4
Click the
PostScript tab.
5
Choose
PostScript 3 from the
Compatibility list box.
6
Click the
Composite tab.
7
Enable the
PostScript 3 In-RIP trapping check box.
8
Click the
Settings button.
9
Type a value in one or more of the following boxes:
•
Step limit — specifies a
threshold between color variations. The lower the threshold value, the more likely it is that a trap will be created.
•
Black limit — specifies the threshold at which process black is considered pure black
•
Black density limit — specifies a neutral density value for the black ink
•
Sliding trap limit — specifies the difference between the neutral densities of adjacent colors at which a trap adjusts (slides) from the darker side of a color edge toward the centerline. The lower the sliding trap limit, the more gradual the transition.
To choose In-RIP trapping options, you must have selected PostScript 3 from the Compatibility list box under the PostScript tab in the Print dialog box.
To set inks for trapping
1
Click
File Print.
3
Enable the
Composite option.
4
Click the
PostScript tab.
5
Choose
PostScript 3 from the
Compatibility list box.
6
Click the
Composite tab.
7
Enable the
PostScript Level 3 In-RIP trapping check box.
8
Click the
Settings button.
•
Transparent — the selected ink doesn’t get trapped, but anything beneath it does
•
Neutral density — the neutral density of the selected ink determines how it is treated
•
Opaque — the selected ink is treated as opaque
•
Opaque ignore — the selected ink doesn’t get trapped nor does anything beneath it
To choose In-RIP trapping options, you must have selected PostScript 3 from the Compatibility list box under the PostScript tab in the Print dialog box.
To select a trap color reduction
1
Click
File Print.
3
Enable the
Composite option.
4
Click the
PostScript tab.
5
Choose
PostScript 3 from the
Compatibility list box.
6
Click the
Composite tab.
7
Enable the
PostScript 3 In-RIP trapping check box.
8
Click the
Settings button.
9
Type a value in the
Trap color reduction box.
A reduction value of 100% indicates no reduction, while a lower value reduces the neutral density.