Orion4D · Curves APP

If you've ever opened Photoshop or Lightroom, you already know how to use this node. Orion4D_FXMax_Curves (displayed "Orion4D · Curves APP") is a proper per-channel curves editor in the pack - the same tool colorists use for everything from a gentle S-curve to a full teal-and-orange grade. It's the most "classic editor" node in the Orion4D_FXMax pack, and that's exactly why it's so useful: no new concepts, just the familiar curve graph, in your ComfyUI graph.

How it works

The mechanism matters here because it's what makes the curves smooth. The node interpolates your control points with Catmull-Rom splines - the same smooth curve math the pack's README brags about - then bakes the result into per-channel look-up tables (LUTs) that get applied through PIL. Catmull-Rom means no sharp kinks at your anchor points: a curve you draw comes out buttery, which is why the presets feel cinematic rather than crunchy.

You get separate curves for RGB master and for the R, G, and B channels individually. That's the whole power: a lift in the RGB curve for contrast, a channel tweak for color cast, and you've done a grade. There's a curve_mode choice between Linear and Smooth interpolation, and the "New Preset" entry in the dropdown exists so you can save your own curve sets.

Inputs and outputs

Pack-standard schema:

• image - the IMAGE tensor.
• preset - Linear, Soft Contrast, Matte Lift, Negative, or New Preset.
• raw_settings - "Embedded JSON settings used for workflow portability. Managed automatically by the APP." The curve points serialize into here, so a shared workflow carries your exact curve.
• mask (optional) - apply the curve to only part of the frame.

Outputs: image and mask.

Performance reality check

This is one of the pack's heavy CPU nodes. The README is blunt: it's continuously converting between arrays and PIL objects to build and apply LUTs and blurs. Totally fine for standard image generation - but the pack explicitly advises against leaning on it in video batches, where the round-trips add up. For stills, and for a hand-placed grade after a generation, it's the right tool.

Install

cd ComfyUI/custom_nodes
git clone https://github.com/orion4d/Orion4D_FXMax.git
# restart ComfyUI

ComfyUI Manager search "Orion4D_FXMax" also installs it. No model downloads, Pillow-only.

Gotchas

Curves is where beginners overreach, so a tip: the photorealism playbook says AI images trend oversaturated and high-contrast - pull saturation down 5–10% and add a subtle cast rather than reaching for a dramatic S-curve. The "Soft Contrast" preset is a better starting point than "Negative," and the APP's split-screen preview will save you from curve-blindness. Also, curves + the DCTL Tone Mapper both do tonal reshaping - pick one as your tonal stage or they'll fight.