AI Image Compositing with Seedream v4.5 Edit

Compositing used to require mastery of layer masks, blending modes, and enough patience to match shadows by eye. Seedream v4.5 Edit collapses it into a sentence. Give the model up to 10 reference images, describe the composite, and it returns a 4MP hero image with lighting, perspective, and shadows resolved in one shot. This tutorial walks through the exact mechanics.

What Compositing Means in v4.5

Traditional compositing is manual: cut out subject, paste onto background, adjust color and shadow, blend edges. You do the work of making the combination look believable.

In v4.5, you describe the composite and the model handles matching. Where Photoshop asks "select the region and the fill content," v4.5 asks "describe the scene and I will assemble it."

That does not mean the tool is magic. Well-directed prompts produce great results; vague prompts produce muddy ones. The rest of this tutorial is about directing the model well.

The Four Types of Composites

Most composites fall into one of four patterns. Knowing which pattern you are building tells you how to structure your prompt.

1. Subject + Background

One subject placed into a new environment. Most common composite type.

2. Multi-Subject Scene

Two or more subjects combined into a shared scene - fashion editorials, group shots, product trios.

3. Element Assembly

Building a scene from multiple discrete elements - a table with food, a desk with tools, a flat lay.

4. Style-Driven Composite

A composite where a mood or style reference drives the overall look more than any single element.

The Universal Composite Prompt Template

Take [subject description] from image 1 and place it [position]
in the environment from image 2. Match the lighting direction and
color temperature from [lighting reference image]. Preserve
[what must not change]. Add [supporting details like shadows or
reflections]. Output at 2048x2048.

Fill in the blanks and you have a working prompt for nearly any composite.

Worked Example 1: Subject + Background

Inputs:

• Image 1: Model in a studio wearing a navy coat
• Image 2: A cobblestone street in Paris at dusk

Prompt:

Place the model from image 1 onto the cobblestone street in image 2.
Position her in the center of the frame, walking toward camera.
Match the cool blue-hour lighting from image 2 with soft directional
light from camera-left. Preserve the model's pose, coat, and facial
expression. Add a soft reflection on the wet cobblestones. Output at
2048x2048.

Result: A 4MP editorial composite in 40–50 seconds. 1 credits.

Worked Example 2: Element Assembly

Inputs:

• Image 1: A clean wooden table surface
• Image 2: A cup of espresso
• Image 3: A croissant on a plate
• Image 4: A notebook and pen
• Image 5: A morning light reference (soft window light)

Prompt:

Build a cafe flat lay on the wooden table from image 1. Place the
espresso from image 2 in the center-left, the croissant from image 3
in the center-right, and the notebook with pen from image 4 in the
bottom-right. Match the soft morning window light from image 5 - cool
temperature, directional from camera-top-left. Add realistic cast
shadows under each object. Output a top-down cafe flat lay at 2048x2048.

Result: A five-element composite with consistent lighting and shadows. Still 1 credits, still under a minute.

Build your first composite now. Open Seedream v4.5 Edit.

Worked Example 3: Style-Driven

Inputs:

• Image 1: Plain portrait photo of a person
• Image 2: A vintage film photograph with warm tones and grain

Prompt:

Apply the color grading, contrast, and film grain aesthetic from
image 2 to the portrait in image 1. Preserve the subject's face,
pose, and clothing structure exactly. Do not change the background
composition. Output at 2048x2048.

Result: A style-transferred portrait that reads as one coherent editorial image. Power users lean on this pattern to lock brand aesthetic across a whole campaign.

Lighting: The Hardest Part of Compositing

Lighting mismatch is the #1 reason composites feel fake. Two fixes:

1. Pick a lighting anchor and state it explicitly. Choose one image (usually the background or a dedicated lighting reference) and tell the model to match it. "Match the warm afternoon lighting direction from image 2" works better than "make the lighting nice."

2. Describe direction and temperature. "Soft directional light from camera-left, warm golden hour temperature" gives the model specific targets. "Good lighting" gives it nothing.

If you can name the lighting, the model can match it.

Perspective: The Second Hardest Part

v4.5 is generally good at perspective matching, but it helps to:

• Use reference images with similar camera angles when possible
• Call out perspective explicitly: "viewed from eye level, slight 3/4 angle"
• Avoid combining extreme wide-angle with telephoto references in the same composite

Perspective mistakes usually show up as objects that look slightly "pasted" into a scene. If that happens, add "match the camera angle and perspective from image 2" to your prompt.

Troubleshooting Common Issues

Problem: Subject looks pasted in. Fix: Explicitly match lighting and add contact shadows in the prompt.

Problem: Color temperature feels off. Fix: Pick one image as the color anchor and reference it: "Match the warm color temperature from image 3."

Problem: Model ignored one of my reference images. Fix: Name it explicitly in the prompt ("using the texture from image 4"). Unnamed references get deprioritized.

Problem: Composite looks over-stylized. Fix: Remove any style references and rely only on the base images. Style references can dominate a prompt.

Problem: Details drift between iterations. Fix: Add "preserve X, Y, Z exactly" for the critical elements. Without that, the model may reinterpret.

Pro Patterns

• Anchor + variants: Lock your prompt template with 3 inputs, then swap one reference to generate variants quickly.
• Progressive compositing: For very complex scenes, do it in two passes - composite half the scene first, then feed the result back as an input.
• Style locking: Keep a 2–3 image "brand mood" reference set and include it in every composite for visual consistency.

Next Steps

Compositing is where Seedream v4.5 stops feeling like a filter and starts feeling like a digital art director. Once you are comfortable with multi-image prompts, the whole catalog of production work opens up.

Read the multi-image editing guide for deeper context on input ordering, the product photography walkthrough for commercial examples, or the complete v4.5 Edit guide for the full model overview.

When you are ready, /create/seedream-v4-5-edit has the tool waiting. Your 10 free credits are enough for 10 full composites.