QUICK START
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Download repository as ZIP. Copy paste scripts directory from repository to: C:\Users\User\Documents\ComfyUI_windows_portable
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Edit convert_spectral.bat — set your checkpoint filename: set "CKPT_NAME=FernflowerAI-2D.safetensors"
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Double-click convert_spectral.bat. Script will generate: -> your_model_long248.safetensors in ComfyUI\models\checkpoints directory
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Create directory sdxl_long_context in ComfyUI\custom_nodes directory
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Copy paste __init__.py and nodes.py to sdxl_long_context directory
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Restart ComfyUI
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Use workflow_sdxl_long248.json from examples directory
IMPORTANT
- Always convert from ORIGINAL checkpoint, not already converted
- Prompts up to 77 tokens = almost identical to original model
- Only 248 tokens is stable. 512+ breaks the model.
- Works with any SDXL checkpoint (base, fine-tuned, merged)
- VRAM increase is minimal (~0.5 GB)
LICENSE: MIT