# Image Generation Model Selection

Source: cutout.pro/model-comparison/imagen-vs-nanobanana + Gemini API model audit (2026-05-10)

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## Available Models (via Google Gemini API)

### Imagen 4: Quality Mode
Model ID: `imagen-4.0-generate-001`
Also available: `imagen-4.0-ultra-generate-001`

Strengths:
- Photorealistic, high-fidelity output
- Handles complex prompts with multi-element consistency
- Superior text rendering inside images
- Best for brand-critical, final-delivery assets

Use for:
- Hero background images
- Service page headers
- Marketing and case study visuals
- Any image that ships to production

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### Nano Banana (Gemini 2.5 Flash Image): Speed Mode
Model ID: `gemini-2.5-flash-image`

Strengths:
- Low latency, high volume
- Cost-effective for rapid iteration
- Good for concept previews and brainstorming

Use for:
- Draft previews before committing to Imagen 4
- AI chatbot or interactive UI image generation
- Avatar or thumbnail generation at scale
- Rapid iteration when exploring compositions

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### Imagen 4 Fast: Budget Mode
Model ID: `imagen-4.0-fast-generate-001`

Use for:
- Quick internal previews
- Non-public-facing visuals
- High-volume batch jobs where quality is secondary

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## Recommended Workflow

Step 1: Draft with Speed Mode (`gemini-2.5-flash-image`)
Generate 2-4 variations quickly. Confirm composition, subject, and tone. Low cost.

Step 2: Refine with Quality Mode (`imagen-4.0-generate-001`)
Take the winning prompt from step 1. Generate final version at full quality.
This is the image that goes into the site.

Step 3: Review against brand palette
Check that image tones align with the project's color tokens from `tokens.css`.
All hero images need to work behind dark overlays.

Step 4: Save to project assets
Path convention: `assets/images/{page}-{slot}.jpg`
Examples: `hero-bg.jpg`, `about-visual.jpg`, `services-bg.jpg`

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## Notes

- Never use Nano Banana for final production images on client sites
- Imagen 4 Ultra adds marginal quality gain over standard: not worth the cost for web assets
- All images should be exported as JPEG at 85% quality, max 1600px wide, for web performance
- Run generated images through the site CSP: ensure `img-src` allows `self` and `data:` only (no external CDN hotlinking)