Flex Mask Opacity ⚡🅡🅞🅣🅘

This is the simplest node in the Flex mask family, and that's exactly its use case: a single knob that caps how strong a mask is allowed to get, with the option to let that cap move over time instead of sitting fixed. Think of it as a volume control for a mask's visibility rather than anything that reshapes it.

How it works

max_opacity sets a ceiling on the mask's output strength - the mask's own values get scaled so nothing exceeds that cap. On its own that's not much more than a strength multiplier, but wire in an opt_feature and set feature_param to max_opacity, and the ceiling itself can rise and fall with an audio or motion signal - a mask that fades in and out with a beat, or dims and brightens with scene brightness, without you hand-keyframing a single value. feature_mode decides whether that modulation is relative (nudging around your set ceiling) or absolute (scaling from zero up to it), and feature_threshold gates how strong the incoming feature has to be before it's allowed to move anything at all.

Inputs and outputs that matter

• masks (required, MASK) - the mask to scale.
• max_opacity (default 1, 0–1) - the ceiling on the mask's output strength.
• opt_feature (optional, FEATURE) - connect to let the ceiling pulse over time.
• Output - a single MASK.

Installing it

Via ComfyUI Manager: search "RyanOnTheInside," install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/ryanontheinside/ComfyUI_RyanOnTheInside.git
cd ComfyUI_RyanOnTheInside
pip install -r requirements.txt

then restart. Pure scaling math - no models involved.

Common issues & troubleshooting

Mask barely visible even at max_opacity 1. If your source mask's own values never reach full white to begin with, capping at 1 won't brighten it - this node only ever scales down, it can't push a mask brighter than its own source values. If you need it stronger than that, look upstream at whatever produced the mask, or layer FlexMaskBinary first for a hard cutoff instead.

Feature-driven pulsing looks flat. Check feature_mode - relative centers the modulation around your set max_opacity, so if that value is already near 1, there's little headroom left for the feature to push it any higher; try absolute if you want the full range from zero to your ceiling to be in play.

Reactivity seems inert. As with every Flex mask node, confirm feature_param is actually set to max_opacity and not left on None - a connected opt_feature with no target parameter does nothing.