Using Layers for Transparency and Clipping in Illustrator CS4
Illustrator Layers: An Editing Tool
Layers are misunderstood and underutilized in Illustrator. Many of my Illustrator students, migrating from a Photoshop mindset, needlessly over-rely on layers as a selection technique. Yes, sometimes it's helpful to break down major components of a project into layers in Illustrator. But, unlike in Photoshop, where the underlying pixel-based logic of artwork often mandates that there are no coherent paths to select, paths in Illustrator are easy to select. Add the ability to double-click on all kinds of objects, including not only paths (and, yes, layers) but compound paths, gradient mesh objects, and clipping masks. Breadcrumbs make it easy to keep track of where you are on the isolation path.
So, while layers in Illustrator don't play the same essential role in making objects editable that they do in Photoshop, Illustrator layers do play a valuable rolejust not (or even mainly) as a tool to organize and isolate objects in an illustration.
In this article, we'll explore three ways in which layers can be used to edit artwork in Illustrator:
- Using layers to generate clipping masks
- Defining transparency for all objects in a layer
- Applying effects to entire layers
Before going into how to use layers as an editing tool, let's review some basic techniques for creating and managing layers.