Lesson 01
01. Prompt Basics: From Description to Image
Structure prompts with subject, environment, lighting, camera, and quality tags for Stable Diffusion.
Prompt structure
A reliable prompt reads like a shot list:
- Subject & action — who/what is in frame and what they are doing
- Environment — location, era, weather, props
- Lighting & mood — golden hour, neon, soft studio, dramatic rim light
- Camera / medium — wide shot, 85mm portrait, watercolor, cel shading
- Quality boosters — use sparingly (
sharp focus,high detail)
Weighting and negatives
Use parentheses for emphasis (red dress:1.2) and brackets to de-emphasize [busy background:0.8]. Negative prompts remove artifacts: blurry, watermark, extra fingers, text, lowres.
For SDXL, a short negative often beats a long laundry list. For SD 1.5, slightly longer negatives can help with anatomy.
Style vs. content
Separate content (what must appear) from style (how it should look). Example content: elderly baker holding sourdough. Style: warm bakery interior, flour dust, soft window light, documentary photo.
If style words fight the subject (anime + photoreal skin), pick one primary medium.
Debugging bad outputs
| Symptom | Try |
|---|---|
| Wrong subject | Move subject to the front; add (subject:1.2) |
| Flat lighting | Name a light direction and color temperature |
| Busy background | Negative prompt clutter; simplify environment |
| Wrong aspect | Match ratio to composition (portrait vs landscape) |
Exercise
Write three prompts for the same subject with different lighting only. Keep seed fixed if available. Compare how light changes mood without altering the subject.