Character consistency is hard because video models are optimizing for motion, not identity. Without clear anchors, faces and outfits drift across clips. The good news: you can dramatically reduce drift with a repeatable prompt structure and a few stability locks.
This guide explains why characters drift, how to lock a consistent identity, and how to fix drift when it happens.
Why Characters Drift
- Prompts describe the scene but not the identity.
- Style and lighting change between clips.
- Motion is too aggressive for close-up faces.
- Background complexity distracts the model.
Prompt Patterns for Consistency
- Repeat a short identity line in every prompt.
- Use a single wardrobe descriptor (color, fabric, silhouette).
- Keep the camera move the same across the series.
- Anchor the subject with "stable face, preserve features."
A close-up portrait of [character identity line]. Camera: slow push-in. Soft studio lighting. Stable face, preserve features, consistent style.Style and Lighting Lock Techniques
- Use one lighting phrase across all clips (soft studio lighting).
- Keep one style label (cinematic realism, documentary, etc.).
- Stick to one framing (close-up or medium shot).
- Reduce motion strength for face stability.
Do and Do Not Checklist
- Do: reuse the same identity line in every prompt.
- Do: keep backgrounds simple and consistent.
- Do: use slow push-in instead of fast tracking.
- Do not: change style keywords every clip.
- Do not: mix wide shots with close-ups in the same series.
- Do not: stack too many descriptive adjectives.
Fixing Drift (Step-by-Step)
- Reduce motion strength and switch to slow push-in.
- Add "stable face, preserve features, no distortion."
- Remove extra style words and keep one style label.
- Use a simpler background and stronger lighting cue.
- Regenerate with one change at a time.
Related Resources
- Style consistency: style consistency
- Troubleshooting: common failures and fixes
- Image-to-video: image-to-video
- Text-to-video: text-to-video
FAQ
What is the best framing for consistent characters?
Medium shots and close-ups are most stable. Keep framing consistent across clips.
Should I repeat the same prompt every time?
Repeat the identity line, lighting, and style. Change only the action or scene.
What if the face still changes?
Reduce motion and add stronger constraints like "stable face, preserve features." Use simpler backgrounds.