How do I block colors from showing through transparent objects?

By the experts at Adobe. © 2005 Adobe Systems Incorporated.

You're using Adobe® InDesign® CS2 to create a logo with overlapping ovals in transparent hues. How do you keep the color from showing through the overlapped areas? Use the Knockout Group option in the Transparency palette. This command makes the opacity and blending attributes of every object in the selected group knock out—that is, visually block out—underlying objects in the group. Only objects within the selected group are knocked out.

First apply the blending modes and opacity settings to the individual objects that you want to knock out. Next arrange the objects according to your design preference, with some areas overlapping. Use the Selection tool to select the objects you want to knock out. Choose Object > Group. In the Transparency palette, select Knockout Group. (If the option isn't visible, select Show Options in the Transparency palette menu.)