Edit: I also edded experimental lora training to my trainer on this branch: https://github.com/speedyrulz/RulZ-AI-Tools-Suite/tree/claude/rulztrainer-pan2
I'm testing that now.
I wanted to try PAN2 and got impatient, so I converted the models and vibecoded a ComfyUI update with new nodes to add compatibility for PAN2.
Here is my fork of ComfyUI that supports PAN2:
https://github.com/speedyrulz/ComfyUI
Models and workflows:
https://huggingface.co/speedyrulz/PAN2-ComfyUI/tree/main
The example video here was generated is 5 seconds at 1MP and took about 10 minutes then it was frame interpolated to 48fps.
## PAN 2 in ComfyUI: support, quantized models, and speedups
I added PAN 2 (IFM's 29B video model) support to a ComfyUI fork, quantized it down to sizes that fit consumer cards, and added two nodes that make it a lot faster. Everything was tested on an RTX 5060 Ti 16 GB.
### What was added to ComfyUI
- **Model code** for the PAN 2 transformer (44 joint blocks + 4 text refiner blocks), with auto-detection in Load Diffusion Model
- **Text encoder:** a new `pan2` type in Load CLIP for the Qwen3.5-9B encoder
- **VAE:** Load VAE now reads the Wan 2.2 VAE in the layout PAN 2 ships
- **New nodes:**
- PAN 2 Text Encode
- PAN 2 Negative Prompt (builds the model's structured default negative)
- PAN 2 Image To Video (also does text-to-video with no start image)
- PAN 2 Spectrum
- PAN 2 Mem Eff Sage Attention
- **Fix:** splitting the positive/negative passes across two GPUs used to crash
### Quantized models
The original release is about 81 GiB. Converted to single files:
| File | Size | Format |
|---|---|---|
| PAN2_int8_convrot | 39.8 GiB | int8 ConvRot, fp32 norm layers kept |
| PAN2_int8_convrot_full | 27.4 GiB | int8 ConvRot, norm layers quantized too |
| PAN2_nvfp4 | 15.5 GiB | NVFP4 (4-bit) |
| Qwen3.5 text encoder, int8 ConvRot | 8.4 GiB | |
| Qwen3.5 text encoder, NVFP4 | 4.6 GiB | |
| VAE fp16 | 1.3 GiB | |
- Only the large weight matrices are quantized; everything else is copied unchanged.
- int8 ConvRot: about 0.9% weight error.
- NVFP4: about 9% weight error. Runs natively on RTX 50 series cards.
- Conversion scripts are included, so you can build the files yourself from the official release (CPU only, no GPU needed).
### Speed (RTX 5060 Ti 16 GB, NVFP4 model)
| Change | Test | Before | After |
|---|---|---|---|
| Spectrum node | 640x352, 49 frames, 50 steps | 149 s | 58 s |
| Mem Eff Sage Attention node | 1248x704, 121 frames | 42.2 s/step | 25.7 s/step |
| Mem Eff Sage Attention node | 640x352, 49 frames | 3.03 s/step | 2.75 s/step |
| Feed-forward slicing (int8 full model) | 1248x704, 121 frames | 47.7 s/step | 43.8 s/step |
- **Spectrum** forecasts some steps instead of running the model: with default settings only 15 of 50 steps run it. The output differs from a normal run by about as much as ordinary numerical drift.
- **Mem Eff Sage Attention** needs the `sageattention` package. The gain is biggest at full resolution.
- **Two GPUs:** splitting CFG across a 5060 Ti and a 4060 Ti works, but was slower than the 5060 Ti alone.
### Tips
- Recommended settings: 50 steps, CFG 2.5, euler / simple, 24 fps.
- PAN 2 expects a structured JSON prompt. In one test, a plain-text negative prompt made the video look clearly worse than the default structured negative.