For the complete documentation index, see llms.txt. This page is also available as Markdown.

Signal Range

Full range vs Video range

Overview

When integrating OmniScope with OpenFX, users can choose between two signal modes: Full Range and Video Range. The choice affects how pixel values leaving Resolve are mapped into OmniScope's internal code-value space — and, as a consequence, what the legal-range graticules actually mean.

Signal range selection in OpenFX plugin settings

What "video range" and "full range" mean

Both modes use the same 10-bit container (0–1023 code values), but they scale the signal differently.

Mode
Black
Nominal white
Headroom
Footroom

Video Range (a.k.a. narrow / legal / SMPTE)

code 64

code 940

941–1019 ("super-whites")

1–63 ("blacker than black")

Full Range

code 0

code 1023

none

none

Video Range is the traditional broadcast convention inherited from analog composite video — the signal is delivered with deliberate headroom above and below the nominal 0–100 IRE window for analog over-/undershoots. Legal-range QC (EBU R103, SMPTE RP 2077) is defined on these ranges.

Full Range uses the entire code-value space. It's the native convention for computer-generated content, stills, and modern digital cameras recording in scene-linear or log formats. There is no footroom/headroom — code 0 is absolute black, code 1023 is absolute white.

When to use which

Video Range

Choose Video Range when your goal is to verify narrow-range legal delivery — i.e. you want to see the 64 / 940 guides on the waveform, catch super-whites that exceed 940, or fail pixels that punch below 64.

  • Use case: broadcast or streaming QC where the deliverable is Rec. 709 / Rec. 2020 narrow range and you need to match a spec like R103 or ARIB TR-B32.

  • Headroom and footroom are preserved and visible; you can observe the full 1–1023 excursion of the source.

Full Range

Choose Full Range in digital production pipelines where narrow-range legal checking is not the point — for example, grading ACES or DaVinci Wide Gamut timelines, working with stills or RAW, or checking CG renders.

  • Use case: scene-linear or wide-gamut grading where the signal has already been expanded to fill the full 0–1023 container.

  • The signal is clipped to 0–1023 in a 10-bit environment; anything outside that range in the source is lost at the transport boundary, so narrow-range over/undershoots are no longer recoverable once the signal crosses into OmniScope.

  • Legal-range graticules are meaningless in this mode because there is no deliberate headroom/footroom to check against.

Important: Video Range mode preserves the ability to detect super-whites; Full Range mode trades that ability for headroom-free signal fidelity. The choice should match the color-science stage you are measuring, not your personal preference.

Summary

Choose Video Range for rigorous adherence to broadcast narrow-range specs; choose Full Range for digital-native pipelines where every code value matters and there is no "legal range" to check against.

For additional support or to address any concerns, please contact OmniScope support.

Last updated