Section 7 · Image Construction & Compositing

Layers

Definition

Stacked, independently editable levels within a raster document, composited top to bottom.

Why it matters

Layers make a complex image editable. Flattening early — or working on a single layer — forecloses every decision you might want to reverse.

Example

Keeping each collage source on its own named layer so any element can be repositioned or removed without touching the rest.

Teaching note

Requiring the layered working file as a submitted deliverable, not just a flattened export, is the only reliable way to make layer discipline visible.