Harmonize is a Photoshop AI tool (Adobe Firefly Model 3) that instantly matches the lighting and color of a composited subject layer to its new background in one click, returning three variations per generation and consuming generative credits.
Where it lives: Appears automatically in the contextual taskbar for any layer with a layer mask; also reachable via Layer > Harmonize, or by searching 'harmonize' in Photoshop's Help.
Workflow: Drag subject onto background → run Remove Background to auto-mask the subject (this also unlocks Harmonize, since it requires a layer mask) → position/size the subject → run Harmonize.
Usage note: As of Aug 2026 the tool was newly out of beta; single-shot output isn't always convincing, so generate one or two extra passes before accepting a result.
Chaining: Harmonize's lighting match persists through later edits — e.g. a subsequent Select All + Generative Fill using a partner model (see Whole-Image Select + Conversational Prompt (Generative Fill Partner Models)) to change clothing/content keeps the matched lighting, provided the order is mask → harmonize → content edit.
Related: Generative Fill Background Compositing Workflow, Camera Raw Grain to Unify AI Composite Texture.