CA_HueQualifier — Compositing Academy
Free Nuke Tool

Hue Qualifier

Pro-grade color keying for Nuke — inspired by DaVinci Resolve.

Target colors with surgical precision using independent Hue, Saturation & Luminance qualifiers
Visual interface — see what you're keying instead of guessing with sliders
Lock all three falloff curves together for one-handed adjustments
Faster, cleaner secondaries than Nuke's built-in HSV Tool
Download Free

Nuke 16+ recommended · BlinkScript GPU · Requires NukeX Indie or NukeX Commercial · Linux, Mac & Windows

The Node

One node. Three axes of color.
CA_HueQualifier
Hue
Saturation
Luminance

Why H · S · L?

Three colors. One word in common.
Brick
wall
Sports
car
Wine
bottle

All three are "red." The hue is the same; the saturation and luminance are not.

A real qualifier lets you say this red, this vivid, this bright — and isolate exactly the surface you're after. That's how colorists work in DaVinci. Now you can work the same way in Nuke.

Adaptive UI

HDR-aware. Auto-fits to your plate.
SDR 0 → 1.0
0.00.250.50.751.0
Analyze
HDR 0 → 4.2
0.01.02.03.04.2

Working with log, ACES, or HDR plates? Toggle HDR Mode and hit Analyze. The luminance qualifier scans your image, finds the actual maximum pixel value, and rescales the entire UI from 0 → 1.0 out to 0 → max — so you can finally select highlights that blow past 1.0 without fighting the slider.

Features

Resolve-Style 3-Band Qualifier

Hue · Saturation · Luminance

Three independent qualifier bands in the spirit of DaVinci Resolve's HSL Qualifier — the industry standard for secondary color isolation. Pick a center, set a width, and shape the falloff on each axis.

  • Independent Hue, Saturation & Luminance ranges
  • Per-band center, width, and soft-edge falloff
  • Sample colors directly from the viewer
  • Output a clean alpha matte ready for grade or comp

Lock Falloffs Together

One slider, three curves

The signature feature. Link the soft-edge falloffs of all three bands so a single drag tightens or loosens the whole key in one move — perfect for dialing in a matte without juggling three sets of controls.

  • Symmetric or proportional linking
  • Unlock individual bands when you need surgical control
  • Reduces a typical 6-handle adjustment to 1

Visual, Not Numerical

See your selection at a glance

Nuke's HSV Tool gives you blind sliders. HueQualifier gives you visual qualifier bars — your selection range is drawn directly on top of the spectrum, so you always know exactly what's in and what's out.

  • Live qualifier bars over hue, sat, and luma spectrums
  • Soft-edge zones rendered as gradient falloffs
  • Matte-only viewer mode for fast refinement

BlinkScript GPU Backend

Real-time on 4K plates

Built on BlinkScript so the entire qualifier — three bands, soft falloffs, and matte output — runs on your GPU. Stays interactive on full-resolution plates instead of bogging down a Read > Grade tree.

  • GPU-accelerated on supported hardware
  • No external dependencies — single .nk install
  • Works in any colour space (linear, log, ACES)

Typical Workflow

1

Sample Your Target

Drop CA_HueQualifier on your plate and ctrl+click the colour you want to isolate. The three qualifier bands snap to the sampled hue, saturation, and luminance values automatically.

2

Refine the Key

Tighten or loosen each band visually. Lock the falloffs and drag a single slider to clean up edges across all three axes at once — no more bouncing between sliders to chase a fringe.

3

Grade, Comp, or Composite

Pipe the matte into a Grade, HueShift, or any downstream node. Perfect for sky replacements, costume re-colours, screen tints, neon isolation, blood-pass keys — anywhere a matte beats a roto.

The Best Way to Key Colour in Nuke

Free forever. No signup. Just download and drop into your .nuke folder.

Download Free

BlinkScript GPU · Nuke 16+ recommended · No external dependencies

Requires NukeX Indie or NukeX Commercial (BlinkScript is not available in Nuke Non-Commercial)