The Knockouts dialog box lets you control how color separation is carried out when objects overlap on the page. The selected option then applies to all objects on every page of the document. You can override this option for any object in the document by using the Sep Options button in its specification sheet-see Separation Options dialog box later in this section.

• Knockouts On All overlapping object areas are knocked out of underlying objects-objects print as you see them on screen. Process-separated objects which overlap use Knockout On even if you've specified Knockouts Off. You can't overprint one process-separated object with another.

• Overprint Black Only The default setting: the overlapping object knocks out corresponding areas of all objects underneath, except where the overlapping object color is black.

• Knockouts Off All overlapping objects overprint the underlying objects-you cannot preview on screen the color changes that will result in print.