Z-Image Turbo is a 6 billion parameter diffusion transformer that generates high-quality images in under a second. But here's the key insight that most users miss: Z-Image doesn't use negative prompts at all. All your control must come from the positive prompt.
This guide will teach you the structured approach that consistently produces professional results.
Unlike traditional Stable Diffusion models, Z-Image Turbo is a few-step distilled model that does not rely on classifier-free guidance during inference. This means:
negative_prompt field is completely ignoredguidance_scale should be set to 0 (or very low)Think of Z-Image as an obedient film crew: if you don't say it, it's allowed. If you say it vaguely, it will improvise.
Structure your prompts with these six components for consistent, controllable results:
Define your primary content with specific details.
Bad: "a person" Good: "A 32-year-old woman with warm olive skin, flowing auburn hair, soft natural freckles"
Include:
Establish the environment and context.
Bad: "outside" Good: "Standing in a lush English cottage garden overflowing with roses and lavender, morning dew on petals"
Include:
Direct the camera like a cinematographer.
Bad: "portrait shot" Good: "Medium close-up in 4:3 frame, subject positioned using rule of thirds, shallow depth of field with soft bokeh background. Shot on Canon 5D with 85mm f/1.4 lens."
Include:
Z-Image responds exceptionally well to lighting direction.
Bad: "good lighting" Good: "Golden hour morning light from upper left, soft fill from ambient reflections, gentle rim light separating subject from background"
Key lighting terms:
soft diffused daylightcinematic warm key lightstudio portrait lightingrim lightingbacklighting with god raysGuide the aesthetic treatment.
Bad: "realistic" Good: "Editorial portrait photography, natural skin texture, filmic color grading with warm undertones, subtle film grain"
Style options:
Since there's no negative prompt, add constraints at the end.
Essential constraints to include:
no text, no watermark, no logoscorrect human anatomy, no extra limbssharp focus, no motion blursafe for work, non-sexual, fully clothedplain uncluttered backgroundFor SFW content, always include these overlapping signals:
Z-Image actually prefers long, detailed prompts:
| Parameter | Recommended | Notes |
|---|---|---|
num_inference_steps |
8 | 4 for speed, 12+ for max quality |
guidance_scale |
0.0 | Turbo doesn't use CFG |
acceleration |
"high" | Sub-second generation |
num_images |
1-4 | Generate variants |
seed |
Fixed when iterating | Random when exploring |
✅ Did I specify "adult" for all human subjects? ✅ Did I describe clothing clearly and modestly? ✅ Did I include "no watermark, no text, no logos"? ✅ Did I define shot type, lighting, and mood? ✅ Is my prompt structured (Subject → Scene → Composition → Lighting → Style → Constraints)?
Subject: A modern [profession] portrait — [age]-year-old [gender] with [skin tone], [hair description], [expression], wearing [specific clothing].
Scene: Minimal bright studio with clean seamless [color] backdrop.
Composition: 3:4 portrait, chest-up, eye-level framing. 85mm lens look with shallow DOF.
Lighting: Clean studio key light with gentle fill, subtle rim light.
Style: Contemporary professional headshot, natural skin texture, [warm/cool] color grading.
Constraints: No logos, no watermarks, no text, correct anatomy, safe for work.Subject: A studio product photo of [product] in [color/material], [key features visible].
Scene: Placed on [surface] with subtle reflection, minimalist studio environment.
Composition: [angle] hero shot, product centered, clean negative space. [Camera/lens reference].
Lighting: Soft box key light from [direction], fill [direction], rim light highlighting edges.
Style: High-end e-commerce photography, ultra-sharp details, accurate material rendering.
Constraints: No hands, no people, no text, no logos, no watermark, pure [background color].Mastering Z-Image prompting means thinking like a film director, not a creative writer. Specify:
The more you direct, the less the model improvises—and the more consistent your results become.
Happy prompting! 🎬
Subject: A hyper-detailed close-up portrait of a young red-haired woman with fair freckled skin, loose curls pinned back by glossy black enamel hair clips. Scene: Her face half-veiled by overlapping cherry blossom branches, petals brushing her temple and casting delicate fluttering shadows over her eyes. Composition: Portrait composition in 3:4 vertical frame, extreme close-up with shallow DOF. Nikon Z8 with 105mm macro lens look, 8K detail. Lighting: Ethereal backlighting with soft god rays filtering through pink blooms, subtle fill, gentle rim light. Style: Intricate photoreal rendering—fine eyelash strands, micro skin texture, pastel bokeh background with filmic grain. Constraints: No logos, no text, preserve natural freckles, avoid oversmoothing.
Example of the 6-part prompt formula for macro portrait photography
Use this MCP tool call to reproduce this generation:
{
"tool": "fal-ai/nano-banana",
"arguments": {
"prompt": "Subject: A hyper-detailed close-up portrait of a young red-haired woman with fair freckled skin, loose curls pinned back by glossy black enamel hair clips.\n\nScene: Her face half-veiled by overlapping cherry blossom branches, petals brushing her temple and casting delicate fluttering shadows over her eyes.\n\nComposition: Portrait composition in 3:4 vertical frame, extreme close-up with shallow DOF. Nikon Z8 with 105mm macro lens look, 8K detail.\n\nLighting: Ethereal backlighting with soft god rays filtering through pink blooms, subtle fill, gentle rim light.\n\nStyle: Intricate photoreal rendering—fine eyelash strands, micro skin texture, pastel bokeh background with filmic grain.\n\nConstraints: No logos, no text, preserve natural freckles, avoid oversmoothing."
}
}A woman in a garden
Basic prompt for comparison - shows how vague prompts lead to unpredictable results
Use this MCP tool call to reproduce this generation:
{
"tool": "fal-ai/nano-banana",
"arguments": {
"prompt": "A woman in a garden"
}
}Subject: A cinematic wide shot of an astronaut standing alone on a rust-red Martian landscape, full spacesuit with reflective visor. Scene: Vast desert terrain with distant rocky mountains, thin dust clouds, two moons visible. Composition: Epic 16:9 frame, astronaut on lower right third, vast negative space. Lighting: Harsh directional sunlight creating long shadows, atmospheric haze. Style: Photorealistic sci-fi cinematography, The Martian aesthetic, orange-teal contrast. Constraints: No text, no watermark, scientifically plausible environment.
Cinematic landscape example demonstrating composition and mood control
Use this MCP tool call to reproduce this generation:
{
"tool": "fal-ai/nano-banana",
"arguments": {
"prompt": "Subject: A cinematic wide shot of an astronaut standing alone on a rust-red Martian landscape, full spacesuit with reflective visor.\n\nScene: Vast desert terrain with distant rocky mountains, thin dust clouds, two moons visible.\n\nComposition: Epic 16:9 frame, astronaut on lower right third, vast negative space.\n\nLighting: Harsh directional sunlight creating long shadows, atmospheric haze.\n\nStyle: Photorealistic sci-fi cinematography, The Martian aesthetic, orange-teal contrast.\n\nConstraints: No text, no watermark, scientifically plausible environment."
}
}