MixMod Options Mask

Global weight blending is MixMod's default, but sometimes you don't want every checkpoint voting on every pixel. That's what this option node is for: you feed it a MASK and it packages it into an OPTIONS bundle that, when attached to a component, makes that model guide only where the mask says it should.

The practical win: a background-focused base model and a character/foreground-focused model can each handle their own territory instead of arguing over the whole canvas. Because the mask is per-component, you can give different regions to different checkpoints in the same pass - model A owns the sky, model B owns the subject, and neither one's CFG leaks into the other's area. It's a coarse, static version of what the Dynamic Mask guider does automatically, and for cases where you know the layout, static is usually better.

Inputs and output

• mask (required) - a standard ComfyUI MASK. Draw it, load it, or generate it; the pack resizes it to the latent's resolution and normalizes it internally, so a rough hand-painted mask works fine.
• prev_options (optional) - chain another options node here. Options merge (later ones layer onto earlier ones), so you can combine a mask with a step range or scale factor on the same component.
• Output: OPTIONS, wired into the options input of a MixMod Guider Component or Guider Component Pipeline node.

One subtlety worth knowing: the mask option only takes effect in the team mode blending path. When any component in the chain carries a mask, the guider switches from global weighted blending to masked blending - each model's CFG'd prediction is applied inside its normalized mask region, and regions with no mask coverage fall back to shared weighting.

Installing

It's part of the ComfyUI-MixMod pack - nothing extra to fetch for this node. ComfyUI Manager → search "ComfyUI-MixMod" → install and restart, or:

cd ComfyUI/custom_nodes
git clone https://github.com/kantsche/ComfyUI-MixMod

No requirements.txt, no model files. The pack's optional companions (GGUF + ExtraModels for Pixart, ControlNet Aux for depth) only matter for those specific mixes.

Troubleshooting

The classic mistake is wiring the OPTIONS output into a guider directly - it won't fit; options belong on the component node, then the component goes to the guider. If the masked region looks like neither model actually guided it, check the mask's white/black polarity against which component it's attached to: white is "this model is active here." And if your mask is very high-res or hard-edged, blur it in another node before feeding it in - the pack's processing handles resizing, but soft edges prevent visible seams where two models meet.