fal-ai/qwen-image-2512-trainer-v2

Qwen-Image-2512 Trainer V2

Fine-tunes the Qwen-Image-2512 model using LoRA to teach it new subjects, objects, or styles from your images and captions.

Input Parameters

image_data_url (required)

URL to a zip archive containing image + caption pairs. Each image (e.g., photo.jpg) should have a matching caption file (e.g., photo.txt).
Supported formats: .jpg, .jpeg, .png, .webp, .heic, .heif, .avif, .bmp, .psd, .tiff

default_caption (default = null)

Fallback caption for images without a .txt file. If not set and a caption is missing, training fails.

steps (default = 2000)

The ideal number of training steps depends on the difficulty of your task.
Simple tasks (e.g., learning a basic object or loose style) often work well with 1000–2000 steps.
Complex tasks (e.g., accurate character likeness, detailed faces, or precise artistic styles) usually require more steps — commonly 2000–4000+.
Tip: Start with the default (2000) and experiment. Train a few versions with different step counts, then compare the results. More steps can improve learning but may cause overfitting if your dataset is small or not diverse enough.

learning_rate (default = 5e-4)

Use 1e-4 for slower/conservative learning, 1e-3 for faster/aggressive learning.

How the Training Works

Image-caption pairing: Each image (e.g., photo.jpg) is paired with its caption file (photo.txt or photo.TXT).

Aspect ratio bucketing: Images are assigned to the nearest bucket matching their aspect ratio, preserving natural proportions.

Caption dropout: 5% of the time, captions are dropped during training to help the model generalize.

Tips for Good Results

Dataset

• Size: 5-10 images minimum, 15-30 optimal for subjects, 20-50 for styles.
• Quality: High resolution images (1024px+) with good lighting and no watermarks.
• Variety: Different poses, angles, lighting, and backgrounds for better results.

Captions

Write clear, descriptive captions in a consistent style:

• Good: a golden retriever sitting on a red couch, soft afternoon lighting
• Bad: dog

Tip: Use an image caption model like Moondream-3

Trigger phrases: For subject training, include a unique trigger word or phrase in every caption (e.g., a photo of ohwx person). Use the same trigger when generating new images later.

Troubleshooting