Flux NF4 - Upscaler Workflow in Comfy
🕑 Added 2024-08-14 11:34:27 +0000 UTCDOWNLOAD BELOW!
Video: https://youtu.be/L5BjuPgF1Ds
With this workflow you'll be able to upscale your newly Flux generated images, and if you follow the video guide, I will show you how you can upscale infinitely (if you have time to wait for the generations).

Download the latest Flux NF4 model: https://huggingface.co/lllyasviel/flux1-dev-bnb-nf4/tree/main
Place in /models/checkpoints/
For troubleshooting, see my getting started with Flux NF4 guide.
Settings
For this upscaling process we'll use the Ultimate SD Upscale node. As we're using Flux, make sure to have relevant values.
Upscale by is the X multiplied. So Upscale by 2 would give you twice the original image size.
Euler at 20 steps
CFG of 1
Tile width and height is 1024
Denoising around 0.15-0.4 are good values. Higher value means more change and detail in each tile, but can also introduce issues like seams or weird generations.

We're adding a new text encoder (prompt) and using no prompt for the upscale. You CAN use a prompt, but it might introduce new generations in each new tile if the denoising is set too high.
The upscale model can be set at your preferred upscaler. Here we're using 4x Ultrasharp. Other notable mentions are 4x AnimeSharp, Realesrgan, NMKD Siax, NMKD Faces.

Generate and achieve amazing upscales!
Don't have hardware to run Flux NF4 or the upscaler takes too long to finish? Use https://thinkdiffusion.com/ experimental Comfy 24gb Turbo machine and drop the workflow there.
TROUBLESHOOTING - NF4 Not loading after all steps completed:
Double check you have installed bitsandbytes (pip install -r requirements.txt)
Go into the folder for the Manager, edit the config.ini and change the security setting from 'normal' to 'weak'. Run Comfy, go into the manager, change the channel to 'dev' then search for the node 'NF4'.
Comments
Olivier E
Hey, have you seen/tried this upscale method that's supposed to give amazing results by just setting the steps to 1 and the tile size to the targeted upscaled image size? https://www.youtube.com/watch?v=oVnTZLRgUC0
Sebastian Kamph
TROUBLESHOOTING - NF4 Not loading after all steps completed: Go into the folder for the Manager, edit the config.ini and change the security setting from 'normal' to 'weak'. Run Comfy, go into the manager, change the channel to 'dev' then search for the node 'NF4'.
Plutos Aurum
Sebastian Kamph
Hey, here's troubleshooting on that https://www.patreon.com/posts/flux-how-to-for-109332332
Sebastian Antony
Hi Seb - What is the URL to "getting started with Flux NF4 guide" - I need to troubleshoot. Thank you.