Vectorscope

The Vectorscope plots chrominance on a circular graph — hue as angle from 0°, saturation as distance from the centre (which represents grey). Use it to evaluate colour balance, skin-tone accuracy, and broadcast-legal saturation.

The classic vectorscope is a plot of the Cb / Cr plane of Y'CbCr — the two colour-difference signals that, together with luma (Y'), fully describe a video picture. "Zero chroma" is the centre point, which is why neutral grey, white, and black of every level all collapse to a single dot there.

Vectorscope with 75 % targets, skin-tone line, and I/Q guides

Vectorscope features: Color Wheel mode, hexagonal rings, trace outline, skin-tone tolerance band, improved target indicators, and I/Q lines

Transform Modes

Mode	Description
YUV	Classic broadcast vectorscope (CbCr plane). Default.
HSL	Saturation-weighted projection — useful for look-dev work

You can switch Orientation to the alternate rotation mode in either transform mode. For a color-wheel-style orientation, use HSL transform with the alternate orientation mode.

Zoom

Zoom into the centre of the plot for fine colour-balance work or expand to see the full gamut.

Input	Action
Mouse wheel	Zoom in / out (continuous)
Middle-click or Double-click	Reset to 100 %

Zoomed vectorscope for precise colour balance inspection

Context-menu presets: 100 % and 200 % for quick switching.

Input Gain

Boost the trace intensity to reveal low-saturation detail.

Input	Action
Mouse wheel (with Mouse wheel gain enabled)	Adjust gain (1×–5×)
Middle-click or Double-click	Reset gain to 1×

Enable Mouse wheel gain in the scope settings to switch the scroll wheel from zoom to gain control.

Graticule & Guides

Graticule and guide settings

Graticule Style

Style	Description
Standard	Circular rings with crosshair, I/Q lines, and target boxes
Hue Vectors	Gradient-based hue visualisation with directional vectors
Color Wheel	Full colour wheel background for intuitive hue reference

Hue Vectors graticule style

Color Wheel graticule style

Guide Elements

Guide	Description
HUE Ring	Colour wheel around the outer edge. Can be dimmed for less distraction.
Crosshair	X/Y axis lines through centre
Rings	Saturation reference rings. Toggle between circular and hexagonal paths.
I/Q Lines	In-phase / Quadrature axis guides
Outer Scale	Tick marks around the outer ring
Vectors	Broadcast colour-bar target markers
Skin-tone Line	Configurable reference line at a user-defined hue angle (default 123°)

Skin-Tone Indicator Band

The skin-tone line can be expanded into an optional tolerance band. This helps you quickly see whether skin hues stay close to your chosen reference angle.

Setting	Description
Show Fleshtone Line	Enables the skin-tone reference axis
Fleshtone Angle	Sets the reference angle (0–359°, default 123°)
Show Tolerance Band	Draws a shaded angular band around the reference line
Tolerance	Band half-width in degrees (±1° to ±45°; common values are ±10° or ±20°)
Tolerance Band Color	Adjust band colour and opacity for visibility

Skin-tone tolerance band on the vectorscope

Interpretation: trace energy inside the band is within your current skin-tone tolerance; trace energy outside the band indicates hue drift from that reference.

Broadcast Targets

Target	Description
75 %	Standard 75 % colour-bar targets (default: on)
100 %	Full-level colour-bar targets

Target colour and position are derived from the active colour space.

Trace Presentation

Setting	Description
Colorize	Tint the trace with per-pixel colour (vs. monochrome)
Linearise trace ("De-gamma")	Apply the inverse EOTF to the trace-density accumulator so that the visual brightness of the plot follows light-linear energy instead of the non-linear R'G'B' code values. Makes shadow-region and highlight-region saturation appear with similar visual weight — useful for log or HDR signals where a raw trace would be dominated by midtone density. It does not change the chroma position of any sample, only how brightly it is drawn.
Smooth Trace	Temporal blend for a cleaner, less noisy look
Enhanced Render	Line-strip rendering instead of point cloud
Gain	Master trace brightness (0.02–3.0)
Enhance Centre	Extra gain applied to the low-saturation core (0–12)

Highlight Trace Edges

Render a coloured outline at the outermost boundary of the trace — highlights the signal extent at a glance.

Trace edge highlight showing signal boundary

Split Tones (L/M/H)

Split the trace into three independent Lows / Mids / Highs buckets, each drawn in its own circle. Buckets are defined by luma (Y', the weighted R'G'B' sum — not scene-linear luminance), so the split follows the same tonal perception a colourist uses when talking about lift / gamma / gain. This reveals how colour shifts across shadow, midtone, and highlight regions.

Vectorscope in L/M/H split mode

L/M/H split with Color Wheel graticule

Setting	Description
Split L/M/H	Enable the three-way split
LM ratio	Boundary between Lows and Mids (default 33 %)
MH ratio	Boundary between Mids and Highs (default 66 %)
Ring brightness	Adjust graticule brightness per bucket
Enhanced render	Sharper rendering for split view

L/M/H Preview

Hold Alt to see a false-colour overlay on the Source Signal showing which pixels fall into each luma range — blue for lows, green for mids, red for highs.

L/M/H preview overlay showing luminance ranges on the source image

Zoomed L/M/H

Use the standard vectorscope zoom controls while inspecting the split circles.

Zoomed L/M/H split — focus on mids

Luma Range Clamp

Instead of splitting into three buckets, clamp to a single luma range using the Min / Max sliders. Only pixels whose Y' falls within the range are plotted — useful for isolating the colour of skin pixels, of highlights alone, or of a specific zone of the image without masking.

Saturation Alerts

Set thresholds to flag illegal or excessive saturation levels.

Saturation alert ring and max ring indicators

Alert	Description
Alert Ring	Coloured ring at a configurable saturation threshold. Signal exceeding it triggers a visual warning. Drag the ring interactively to reposition.
Max Ring	Tracks and displays the absolute maximum saturation contour in real time
Outline	GPU-rendered trace boundary with anti-aliasing. Use the Outline Thickness slider to adjust the rendered width (0.5–5 px).

Each alert has a customisable colour.

Low-Pass Filter

Enable Low-Pass filter to apply a horizontal box blur to the trace, reducing noise and making trends easier to read. Adjustable kernel size (0.5–20).

Global Targets

Global targets appear as RGB reference points on the vectorscope, providing shared colour targets across all scopes and layouts.

Color Pins

When colour pins are placed on the Source Signal, they appear as markers on the vectorscope at the corresponding hue/saturation position.

Colour pins reflected on the vectorscope

Right-click any colour pin on the vectorscope to Set as custom target — a quick way to turn a sampled colour into a global target without manually entering values.

Right-click a colour pin to set it as a custom target

Colour Space

The vectorscope defaults to the working signal. Use Color Space Transform override in Source & Input to evaluate the trace in a selected working/display transform.

Skin-Tone Practice

Skin tones usually align close to the skin-tone axis, a reference direction inherited from the NTSC I/Q colour-difference system. I and Q were axes rotated 33° from Cb/Cr to align the high-bandwidth I (In-phase) axis with the orange/cyan "memory colour" line that human vision is most sensitive to — and the -I direction corresponds roughly to human skin. Most properly exposed skin falls within ~10–20° of that axis regardless of complexion; only hue balance differs, not the underlying axis.

Creative and regional preferences still apply, so use the tolerance band as a visual guide, not a hard rule. A heavily stylised grade will deliberately pull skin off-axis.

Keyboard Shortcuts

macOS	Windows	Action
Mouse wheel	Mouse wheel	Zoom (or Input Gain if enabled)
Middle-click	Middle-click	Reset zoom / gain
Alt (hold)	Alt (hold)	Preview L/M/H split ranges

StreamDeck / Action Editor

Action	Description
VectorScopeZoom	Button: toggle 1×/2× zoom. Dial: fine zoom (±5 %, 35–500 %)
VectorToggleLmh	Toggle Split L/M/H mode

Related

• Global Targets

• Gamut Check

• Skintone Scope

• Available Actions