User Guide

Chapter 3: Objects And Attributes
Setting print properties for objects
Click on the Trap tab of the Object Specs palette to view the overprinting and trapping options for
color separations. Click Apply to apply the settings to selected objects.
Overprinting in color separations
When you output color separations in Canvas, you can specify that an object should overprint, rather
than knock out, objects behind it.
In color separations designed for commercial printing, a front object usually knocks out a hole where
it overlaps other objects; however, you can apply the Overprint Object option to an object to prevent
it from creating knockouts in objects behind it. This can compensate for registration problems on
some printing presses.
For example, if you draw a cyan circle on a yellow background, Canvas knocks the circle out of the
background in color separations so cyan and yellow don’t mix in the circle. If you select the circle and
use the Overprint Object option, the circle prints over a solid yellow background, and the cyan in the
circle mixes with the background yellow, resulting in a green circle.
The effect of the Overprint Object option is not visible on screen. This effect is visible only in the
printed output when you produce color separations. Verify the settings for a particular object by
viewing the Trap tab in the Object Specs palette and then selecting the object.
Color mixing as described previously is not the primary reason for overprinting. It’s more common for
designers to overprint dark objects on lighter backgrounds as a way to prevent a gap from appearing
between the colors if the press registration (alignment) isn’t perfect.
To specify overprinting for objects:
1. Select the vector or text objects to be overprinted.
2. Select the Overprint Object check box on the Trap tab.
3. Click Apply. The appearance of the selected objects does not change on screen, but the
objects will be overprinted in color separations.
To remove overprinting:
Select the objects and deselect the Overprint Object check box. Then click Apply.
Trapping in color separations
When objects of different colors touch, there is the potential for an unsightly gap to appear between
the colors if the piece isn’t printed precisely aligned, or in register.
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