Scopes in an HDR project
In an HDR (HLG) project the scopes measure the HLG signal instead of Rec. 709, and their scales and targets change to match. Use them to see how far a highlight rises above white, and to check that titles and SDR clips sit at reference white.
- Menu
- View ▸ Scopes
- Keys
- ⌃⌘W
- Agent tools
render_frame
This page covers what’s different in an HDR project. For everything else about the panel, see Scopes.
Scopes read the HLG signal
Section titled “Scopes read the HLG signal”Turn the panel on with View ▸ Scopes (⌃⌘W). There’s nothing to set: the scopes follow the frame they’re measuring.
| What the preview shows | What the scopes read |
|---|---|
| An HDR (HLG) project’s picture | The HLG signal, with the scales on this page |
| The picture with Show Ungraded on | The HLG signal, of the ungraded picture |
| The picture with Show SDR Version on | The SDR version, exactly as they would in an SDR project |
Waveform and Parade
Section titled “Waveform and Parade”The Waveform and Parade label every line in cd/m², the same unit as nits. An SDR project labels only 0, 50 and 100 on the same five lines.
| Line | Label (cd/m²) |
|---|---|
| 100 % | 1000 |
| 75 % | 203, drawn dashed |
| 50 % | 51 |
| 25 % | 10 |
| 0 % | 0 |
Each figure is the light a grey at that level gives on a nominal 1,000 cd/m² display.
The dashed 75 % line is HDR reference white, and only an HDR (HLG) signal has it. Titles and SDR material sit on it, because they’re lifted to reference white. HDR highlights rise above it.
The red clip marks stay on the scope’s top and bottom edges, so in an HDR project the top one means a signal at the 1000 line.
The Waveform’s trace is luma, taken with BT.2020’s weights. The Parade shows the red, green and blue signals themselves.
Vectorscope
Section titled “Vectorscope”The vectorscope measures colour with BT.2020’s weights, and its targets are BT.2020’s too. That covers the six colour-bar boxes (R, Mg, B, Cy, G and Yl), the ticks on the rim that stand in for them at 2× and 4× zoom, and the skin line. Judge a colour against these targets, not against where it sat in an SDR project.
Histogram
Section titled “Histogram”The Histogram counts the HLG signal’s levels, and its luma line uses BT.2020’s weights. It has no cd/m² labels.
Captions
Section titled “Captions”Each scope slot’s caption names what it’s reading, so you can tell at a glance which picture you’re measuring.
| Scope | HDR (HLG) signal | SDR project or SDR version |
|---|---|---|
| Waveform, Parade | HLG · cd/m² | Rec. 709 · encoded |
| Vectorscope, Histogram | Rec. 2100 HLG | Rec. 709 · encoded |
With an agent
Section titled “With an agent”render_frame measures the same four scopes and gives an agent their numbers. In an HDR (HLG) project each scope’s JSON adds signal: "hlg", and the sentence that comes back names the HLG signal. The Waveform, Parade and Histogram also add scale:
| Key | What it holds |
|---|---|
unit |
cd/m² |
ticks |
Each line’s percent, level and nits |
reference_white_percent |
75 |
clip_percent |
100 |
Luma and the vectorscope use BT.2020’s weights and targets, and the vectorscope’s matrix reads “Rec. 2020”. A frame asked for as the SDR version gets an SDR project’s scopes, with nothing added. See Check the picture: render_frame.