2.9 KiB
Image Generation Model Selection
Source: cutout.pro/model-comparison/imagen-vs-nanobanana + Gemini API model audit (2026-05-10)
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
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
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
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 site color tokens:
- cobhamtech.com: dark navy (#0c0f18), slate (#1c2d42), blue accent (#2d5a9e), gold (#c79330)
- 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
Cobhamtech.com Image Plan
| Slot | File | Page | Prompt Theme |
|---|---|---|---|
| Hero background | hero-bg.jpg |
index.html | Dark server room, blue ambient lighting, depth of field |
| About story | about-visual.jpg |
about.html | IT professional at clean desk, dual monitors, neutral dark background |
| Services hub | services-bg.jpg |
services/index.html | Enterprise network infrastructure, abstract, dark |
| Intro visual | intro-visual.jpg |
index.html | Business and technology handshake, professional setting |
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-srcallowsselfanddata:only (no external CDN hotlinking)