Trapping with Adobe Illustrator and Aldus FreeHand
How do I specify trapping for graphics created in Adobe Illustrator and Aldus Freehand?
QuarkXPress 3.0's trapping controls enable you to specify the way in which QuarkXPress items are trapped. The Using QuarkXPress manual (pp. 5.13-15) describes how to use the program's trapping controls. However, QuarkXPress does not enable you to control trapping for all color elements. For example, the colors used in imported pictures created in EPS illustration programs such as Adobe Illustrator and Aldus Freehand are not affected by trapping specifications you make within QuarkXPress.
Trapping of the colors in an EPS picture must be done in the program with which the picture was created before the picture is imported into a QuarkXPress document. Correctly trapped color EPS pictures will print correctly when output by QuarkXPress.
Adobe Illustrator and Aldus Freehand each include a manual devoted to desktop color, color separation, and color printing issues. We recommend that you consult these manuals when creating illustrations for use in QuarkXPress documents. We also recommend that you talk to your printer about what kind of trapping works best for his or her particular printing environment before you output color separations. This communication with your commercial printer is vital.
Here are some tips about how to use Illustrator and Freehand to create illustrations that will trap correctly when imported into, separated, and output by QuarkXPress. A reminder: when you use the techniques described below to create traps for color EPS illustrations, the colors will always spread and choke, whether you print composite proofs or color separations. If you do not want the colors in an illustration to trap when you print composite proofs, you may want to create both a trapped and nontrapped version of the illustration.
Spreading a light-colored object into a darker background:
Use an extra stroke to create a trap between an object and its background when the object is lighter in color than the background. A stroke trap has the same effect as a traditional spread trap.
To create a stroke trap in Adobe Illustrator:
1. Select the topmost object of the two adjacent objects you want to trap.
2. Choose Style (Paint menu).
3. If the object has a fill value but no stroke value, click the Process Color or Custom Color button (depending on the type of color assigned to the fill) in the Stroke area.
4. Use the controls in the Stroke area to create the same color selected in the Fill area.
5. Check Overprint in the Stroke area. Make sure Overprint is not checked in the Fill area.
6. Enter a value in the Weight field to specify the thickness of the trap stroke. It's a good idea to consult with your professional printer to determine the amount of trap needed.
7. Click OK.
To create a stroke trap in Freehand 3.0:
1. Select the topmost object of the two adjacent objects you want to trap.
2. Choose Fill and line (Attributes menu); the Fill and line dialog box is displayed.
3. Make sure the color shown in the Color pop-up menu is the same as the color selected in the Fill area in the Line area of the Fill and line dialog box.
4. Enter a value in the Weight field to specify the thickness of the trap stroke. Freehand applies line weight starting at the center of the line, so if you want a .5-point trap, enter 1 in the Weight field.
5. Check Overprint in the Line area. Make sure that Overprint is not checked in the Fill area.
6. Click OK.
Choking a light-colored background into a darker object:
Use a choke mask to create a trap between an object and its background when the object is darker in color than the background. A choke mask trap has the same effect as the traditional choke trap.
To create a choke mask in Adobe Illustrator:
1. Select the topmost object of the two adjacent objects you want to trap.
2. Choose Style (Paint menu); the Paint Style dialog box is displayed. The object should have a fill color specified, but no stroke.
3. Check Overprint in the Fill area. Click OK.
4. With the object still selected, choose Copy (Edit menu). Then choose Paste in Back (Edit menu).
5. Choose Style (Paint menu); the Paint Style dialog box is displayed.
6. Select White in the Fill area in the Paint Style dialog box. Make sure Overprint is not checked.
7. Use the controls in the Stroke area to create the same color selected in the Fill area of the background color.
8. Enter a value in the Weight field to specify the thickness of the choke mask.
9. Click OK.
To create a choke mask in Freehand 3.0:
1. Select the topmost object of the two adjacent objects you want to trap.
2. Choose Fill and line (Attributes menu); the Fill and line dialog box is displayed.
3. Make sure the color shown in the Color pop-up menu in the Line area of the Fill and line dialog box is the same as the Fill color applied to the background object.
4. Enter a value in the Weight field to specify the thickness of the trap stroke. Freehand applies line weight starting at the center of the line, so if you want a .5-point trap, enter 1 in the Weight field.
5. Check Overprint in the Line area. Make sure that Overprint in the Fill area is not checked.
6. Click OK.
Trapping adjacent colors when it's hard to tell which color is darker:
If it's difficult to tell whether the topmost color is lighter or darker than the background, you can split the trap between a choke mask and a stroke trap. For example, if you normally create .6-point traps, create a .3-point choke mask of the the background color and a .3-point stroke trap around the topmost object.
Trapping adjacent colors when both colors are built with common process colors:
When an object and its background(s) share common process colors, press misregistration is not as much of a problem as it can be with spot colors and with illustrations made up of dissimilar process colors. You may not need to specify trapping when overlapping colors are created by one or more of the same process colors.
Trapping text in Freehand:
To trap text against a background color in Freehand,
1. Select the text you want to trap.
2. Choose Fill and stroke from the Effects sub-menu (Type menu); the Fill and stroke dialog box is displayed.
3. Check Overprint in the Stroke area and make sure that Overprint in the Fill area is unchecked.
4. To spread the text into the background, choose the same color from Color pop-up menu in the Stroke area as you selected from the Color pop-up menu in the Fill area.
To choke the background into the text, make sure that the color selected in the Color pop-up menu in the Stroke area is the same as the background color.
Specifying PANTONE Colors in Illustrator and Freehand documents:
QuarkXPress is able to print spot and/or process color separations of PANTONE Colors specified in either Illustrator or Freehand documents. To separate a PANTONE Color contained in an imported EPS illustration, you must first add the PANTONE Color to the QuarkXPress document's color palette. Once the PANTONE Color has been added to the QuarkXPress document's palette, use the controls in the Process Separation area of the Edit Color dialog box (Edit -> Color) to specify it as a spot or process color, depending on how the color was specified in the originating illustration program.
Quark, Inc. has made every effort to see that QuarkXPress works with third-party products. However, due to periodic updating by other manufacturers, we cannot warrant compatibility. Quark, Inc. also makes every effort to ensure the accuracy of FaxFacts. However, Quark, Inc. makes no warranties or guarantees regarding the accuracy of the information herein.
