Documentation Index
Fetch the complete documentation index at: https://docs.bfl.ml/llms.txt
Use this file to discover all available pages before exploring further.
Aspect Ratios
Choose the ratio that matches the compositional intent of your scene. Mismatched ratios force the model to either crop or pad the composition.| Ratio | Format | Best For |
|---|---|---|
| 1:1 | Square | Social media, profiles, product shots |
| 16:9 | Landscape | Widescreen, web headers, presentations |
| 9:16 | Portrait | Mobile, stories, vertical editorial |
| 4:3 | Standard | Classic photography |
| 3:2 | Photo standard | DSLR-style portrait and landscape |
| 21:9 | Ultra-wide | Cinematic, panoramic scenes |
Working Without Negative Prompts
Most FLUX models do not support negative prompts. Even when they can process them, AI models generally struggle with negation — writing “a person without glasses” causes the model to focus on “glasses” and often generate exactly what you were trying to avoid.The Replacement Strategy
When you catch yourself writing negative phrases, use this mental process:- Identify the unwanted element: “no crowds”
- Ask what would fill that space: “What would I see there?”
- Describe the positive: “peaceful solitude” or “empty pathways”
| Instead of… | Write… |
|---|---|
| “no people" | "empty”, “deserted”, “solitary" |
| "without clothes" | "bare skin”, “natural form" |
| "no colors" | "monochrome”, “black and white”, “grayscale" |
| "no text" | "clean surfaces”, “unmarked”, “blank" |
| "no modern elements" | "traditional”, “historical”, “period-accurate" |
| "not dark" | "brightly lit”, “sun-drenched" |
| "not sad" | "joyful”, “content" |
| "not running" | "walking peacefully”, “standing still" |
| "not many" | "few”, “single”, “minimal” |
Practical Examples
Context & Setting
Context & Setting
- Instead of: “a street with no cars” Write: “a quiet pedestrian walkway with cobblestones”
- Instead of: “a landscape without buildings” Write: “pristine wilderness with untouched natural terrain”
- Instead of: “a room with no furniture” Write: “a spacious empty room with polished wooden floors”
Character & Portrait
Character & Portrait
- Instead of: “a person without a hat” Write: “a person with natural hair flowing freely”
- Instead of: “a portrait with no glasses” Write: “a portrait showing clear, unobstructed eyes”
Mood and Atmosphere
Mood and Atmosphere
- Instead of: “not dark or scary” Write: “peaceful, welcoming, and warm atmosphere with soft golden lighting”
- Instead of: “not too realistic” Write: “stylized illustration with simplified forms and bold color blocks”
Compositional Control
Compositional Control
- Instead of: “portrait with no background distractions” Write: “portrait with smooth gradient background transitioning from deep blue to black”
The Beach Progression
Positive framing combined with specificity consistently produces better results:When Positive Alternatives Don’t Work
If you’re still getting unwanted elements despite positive framing:- Be more specific about what you do want in that space
- Front-load the positive description — word order signals priority
- Add more descriptive detail to strengthen the positive alternative
- Use environmental context to make the positive element feel natural
Prompt Upsampling
FLUX.2 [pro], [max], and [flex] automatically enhance short prompts by adding visual detail and context while preserving your original intent. This is useful for:- Quick iterations without crafting detailed prompts
- Exploring creative variations from a short concept
- Generating richer output from a basic idea