To customize a halftone screen

1Click File ` Print.

2Click the Separations tab.

3Enable the Print separations check box.

4Enable the Use advanced settings check box.

5Click Advanced.

6Change any of the following settings:

•Screening technology

•Resolution

•Basic screen

•Halftone type

You can set the screen frequency, screen angle, and overprint options for spot colors as well as process colors. For example, if you have a fountain fill made up of two spot colors, you can set one to print at 45 degrees and the other at 90 degrees.

Specifying In-RIP trapping settings

In-RIP trapping allows you to specify advanced trapping settings. Before selecting InRIP 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 will be created by specifying a step trap limit. If trap colors are of similar neutral densities, the trap placement will be adjusted accordingly. The step trap limit specifies a threshold at which a trap will adjust.

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.

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To select a trap width

1Click File ` Print.

2Click the Separations tab.

3Enable the In-RIP trapping check box.

4Click Settings.

5Type 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

1Click File ` Print.

2Click the Separations tab.

3Enable the In-RIP trapping check box.

4Click Settings.

5From 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 option.

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 a threshold

1Click File ` Print.

2Click the Separations tab.

3Enable the In-RIP trapping check box.

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4Click Settings.

5Type a value in one or any 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 select 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

1Click File ` Print.

2Click the Separations tab.

3Enable the In-RIP trapping check box.

4Click Settings.

5Click Type, and for each color separation, select one of the following:

• 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 select 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

1Click File ` Print.

2Click the Separations tab.

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