How to Train a Consistent Character LoRA for Stable Diffusion
The holy grail of AI art isn't just generating a beautiful image; it's generating the SAME beautiful person twice. If you want to create a comic book, a brand mascot, or an influencer, you need a LoRA.
Stable Diffusion is like a dream machine. It knows what "a woman" looks like, but it doesn't know what your specific character looks like. Every time you generate an image, you get a random face. This makes storytelling impossible.
The solution is training a LoRA (Low-Rank Adaptation). Think of a LoRA as a small file (usually 100MB) that "patches" the main AI brain. It teaches the AI one specific concept—your character—without retraining the entire massive model.
Step 1: The Dataset (Quality > Quantity)
Garbage in, garbage out. The most critical step is gathering your images. You don't need hundreds of photos. For a character, 15 to 30 high-quality images are better than 100 blurry ones.
Your Checklist:
- Variety: Different angles (front, side, looking up), different lighting, and different distances (close-up, full body).
- Consistency: The character's core features (hair color, eye shape, tattoos) must be visible and consistent.
- Crop: Crop your images to 512x512 or 1024x1024 pixels.
Step 2: Captioning (Teaching the AI)
You need to tell the AI what it is looking at. We use text files associated with each image.
The Golden Rule of Captioning: Describe everything except the character's unique traits. Why? Because you want the "Trigger Word" to contain those unique traits.
Step 3: Training Settings (Kohya_ss)
We use a tool called Kohya_ss. It is the industry standard GUI for training. While there are hundreds of settings, here are the ones that matter for 2026:
- Repeats: 10 (How many times the AI looks at each image per epoch).
- Epochs: 10 (How many full cycles).
- Network Rank (Dim): 32 or 128 (Higher captures more detail but risks large file size).
- Alpha: Usually half of the Rank (e.g., 16 or 64).
Comparison: Why LoRA Wins
Before LoRA, we used other methods. Here is why LoRA became the standard.
| Method | File Size | Training Time | Consistency |
|---|---|---|---|
| Dreambooth | 2GB - 4GB | Slow | High |
| Textual Inversion | 10KB | Fast | Low |
| LoRA | 140MB | Fast (20 mins) | High |
Using Your LoRA
Once trained, you get a `.safetensors` file. Place this in your Stable Diffusion models folder. To use it, you simply include the trigger word in your prompt.
Boom. The AI now knows exactly who 'sks_girl' is and will render her face perfectly, even though she has never been to the moon.
Conclusion
Training a LoRA is the gateway to professional AI artistry. It transforms you from a "Prompt Engineer" rolling the dice into a "Director" with a consistent cast of actors.

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