Background Swap / Replace

A photo → the same subject dropped onto a brand-new background.

Category: edit · Difficulty: Beginner · ~Time: 3 min

What you'll make

Keep your subject (a person, product, or pet) exactly as-is while swapping the background for something new — a studio sweep, a beach, a gradient, or a branded set. Use it to rescue a great photo shot against a messy room, or to mass-produce on-brand variants of one hero shot.

Models used

🎨 Image — Nano Banana 2 (edit) (resolve live; e.g. google/nano-banana-2/edit)
🎨 Image (alt) — Seedream 4.5 (edit) (resolve live; e.g. bytedance/seedream-v4.5/edit)
💬 LLM — Claude (to describe the new background richly), optional

Steps

Upload the source photo — "Upload this local photo so it has a URL." → maps to atlas_upload_media; keep the returned download_url.
(Optional) Expand the background prompt — "Describe a warm sunset beach background in one vivid sentence." → maps to atlas_chat with Claude.
Swap the background — "Replace the background with [scene], keep the subject, pose, and lighting on the subject unchanged." → maps to atlas_generate_image with Nano Banana 2 (edit), passing the uploaded URL as the input image.

Tip: ask the agent to atlas_search_docs for the model first so it pulls the live edit schema (input-image field name, supported sizes).
Review & iterate — if edges look cut-out, re-run asking for "matched ambient lighting and a soft contact shadow under the subject."

Prompt starters

Replace the background with a clean seamless studio sweep in soft beige.
Keep the person, their pose, hair, and clothing exactly the same. Match the
lighting on the subject to the new background and add a subtle contact shadow.

Swap the background to a sunlit tropical beach at golden hour, gentle bokeh.
Do not alter the product itself — preserve its shape, label, and reflections.

Tips & variations

Swap Nano Banana 2 (edit) → Seedream 4.5 (edit) for stronger relighting and photoreal contact shadows.
For hard-edged products (bottles, boxes), explicitly say "preserve label text and edges" to stop the model from redrawing them.
Generating many variants? Loop the same uploaded URL with different background prompts — upload once, reuse the URL.