Understanding a monitor's HDR
Blacks, highlights, and color: adjust the examples to see what each part contributes to the HDR image.
Range is more than the peak
HDR aims to preserve differences from shadows to bright highlights. Raising overall brightness does not achieve the same thing: blacks, detail, and light must work together. In the example, change the black level while keeping white fixed.
The same white, a different black
Raising black makes shadows look washed out and reduces their separation from highlights. The drawing's white stays the same.
Relative, exaggerated simulation with no assigned contrast ratio. The screen on which you read this guide also limits the black level you can see.
HDR10 and PQ
HDR10 uses PQ and static metadata. PQ describes absolute luminance and is included in BT.2100 alongside HLG, another HDR function. The PQ scale supports up to 10,000 nits; content and displays do not have to reach that limit.
Accepting HDR10 does not establish the contrast or brightness a panel can display.
What to look for
- Input and content compatibility.
- Measured HDR performance, beyond the accepted signal.
Avoid this confusion: Confusing the ability to receive HDR with great HDR reproduction.
DisplayHDR and True Black
VESA certifies multiple image requirements. DisplayHDR and DisplayHDR True Black are different families; the number on the label does not by itself summarize a monitor's behavior.
The criteria evolve. Do not assign the latest CTS version's requirements to every model carrying the same number.
What to look for
- Exact model and certification.
- Applicable CTS version and independent tests.
Avoid this confusion: Treating the name “HDR 1000” in a menu as proof of certification.
How much is illuminated, and for how long, matters
A star, a white window, and a snowy scene make different demands. First change the size of the bright area; then see why the initial peak and sustained level are different figures.
More area, less available intensity
A small detail can concentrate more brightness. Enlarge the window to see how the intensity decreases.
Illustrative relative brightness: it does not reproduce nits or a model's curve. It shows how OLED can reserve more intensity for small details. Area, APL, and test duration remain separate concepts.
A flash and a sustained scene make different demands
The maximum is reached at the start. A figure taken only here does not tell you how long that brightness is maintained.
Schematic curve with a constant pattern and mode. The 60 seconds are this drawing's scale; the shape and duration of the drop do not describe a specific panel. Comparisons require the window size, mode, and measurement protocol.
Brightness, windows, and APL
A 10% window is a pattern occupying that portion of the screen. APL is the average picture level according to the method used: it is not simply the percentage of bright area. Size, background, distribution, and duration affect the test.
A small, brief peak does not describe a sustained bright scene. Two measurements using different patterns may not be comparable.
What to look for
- Small windows, medium windows, and full screen.
- Initial peak and sustained luminance in the same mode.
Avoid this confusion: Comparing figures without knowing the pattern, or calling any 10% window “10% APL.”
ABL and brightness changes
The automatic brightness limiter can reduce luminance as power demand increases. On OLED, it is often noticeable when expanding a bright area. It is different from time-based dimming of a static image.
A uniform-brightness SDR mode can reduce variation by limiting the maximum. It does not increase the panel's sustained brightness capability.
What to look for
- Variation when moving or enlarging windows.
- Differences between modes, changing content, and static images.
Avoid this confusion: Attributing every brightness drop to ABL or recommending disabling protections without distinguishing their purpose.
Lighting pixels or illuminating zones
On OLED, each pixel emits its own light. With Mini LED, a backlight zone serves multiple LCD pixels. This structure helps explain both brightness and halos around small objects.
Where the light comes from
With Mini LED, a zone can cover many LCD pixels. The precision of the two controls is different.
Functional view: it does not show every physical layer or its thickness. Colors identify each function, not the emitters' spectrum.
Small lights against black
The light is the same on both screens. With Mini LED, some illumination spreads into the background; change the zone size to compare the halo.
Visual blooming simulation without showing zones as blocks. Actual halo intensity depends on the panel, algorithm, brightness, and viewing angle.
Local dimming and Mini LED
Local dimming controls backlight zones. Mini LED describes the small emitters; IPS and VA describe the liquid crystal. That is why both IPS Mini LED and VA Mini LED monitors exist.
LCD contrast, zones, and their algorithm work together. More zones alone do not guarantee a better result.
What to look for
- Small objects against black and subtitles.
- Zone response in motion and preservation of dark detail.
Avoid this confusion: Presenting IPS and Mini LED as mutually exclusive categories.
Blooming and halos
On an LCD with zones, an illuminated region can also affect nearby dark pixels. Perception changes with viewing angle, scene, and room lighting.
An algorithm can hide halos by also dimming small details. Both effects should be evaluated.
What to look for
- Stars, subtitles, and moving elements.
- Photos with exposure specified: a camera can exaggerate the halo.
Avoid this confusion: Judging the result solely from an overexposed photo or the zone count.
More colors, even when they are bright
Gamut describes the chromaticities a display covers. Volume adds how much brightness it retains in those colors. First compare gamut boundaries, then raise the example's brightness.
Which colors each gamut includes
The triangles share a scale. Each one's area shows its chromaticity boundaries; protruding areas show where the gamut expands.
Wider does not mean identical
P3 expands particularly on sRGB's reds and greens. Adobe RGB extends farther into greens and cyan. Neither P3 nor Adobe RGB fully contains the other.
CIE 1931 xy primary coordinates, not monitor measurements or a representation of all visible colors. Line colors only identify the gamuts. DCI-P3 and Display P3 share P3 primaries, but not their entire definition. References: sRGB, Display P3, Adobe RGB, BT.2020.
Color has a third dimension: brightness
At moderate brightness, both examples can show similar colors. Raise the level to see why gamut coverage alone does not describe color volume.
Three-dimensional diagram and simulated colors, with no units or measured volume. It does not assign a result to WOLED, QD-OLED, or Mini LED. White brightness and saturated-color luminance are separate measurements; the screen you are reading on limits the representation.
P3 coverage and color volume
P3 coverage indicates how much of those primaries the display covers under the measurement conditions. For monitors, distinguish P3 primaries from the other parameters of the cinematic DCI-P3 standard. Color volume adds the luminance dimension.
A display can cover much of P3 yet lose saturation in very bright colors. A high white peak does not prove high color brightness either.
What to look for
- Coverage, accuracy, and measurement conditions.
- Luminance of saturated colors, not just white.
Avoid this confusion: Equating 99% P3 with perfect accuracy or high color volume.
Rec.2020
An HDR signal can use BT.2020 primaries even when its actual colors occupy a smaller area. Accepting that signal does not mean the display covers the entire space.
The signal container and reproduction capability are different things. The usefulness of a wider gamut also depends on the content.
What to look for
- Measured coverage and the method used.
- Accurate reproduction within the gamut, as well as its extent.
Avoid this confusion: Reading “Rec.2020 compatible” as “100% coverage.”
Respecting the signal and preserving highlights
A display can reach a high peak while darkening midtones. The curve shows that difference. When content exceeds the available range, tone mapping can compress highlights to preserve their detail.
The curve: how much brightness the signal requests and how much is displayed
when the signal requests 300 nits
Output matches the target. The example's midtones are neither lifted nor darkened.
For easier reading, the horizontal axis already converts the signal into its target luminance. A typical PQ EOTF uses signal level on that axis. These are invented teaching curves, not product measurements. Peak tone mapping is not evaluated here.
Preserving differences in highlights
When highlights are compressed, different levels remain distinct. Their brightness relationship changes to fit the display.
Illustrative curves and levels, with no nit scale. Actual results depend on content, metadata, and monitor processing.
PQ / EOTF tracking
The EOTF relates the signal to light output. On a PQ graph, measurement deviation shows where the display brightens or darkens relative to the target. The upper end may adapt to the panel's physical limit.
A single curve does not explain color, halos, or every scene. It must be accompanied by the test conditions.
What to look for
- Shadows, midtones, and the point where highlights begin to compress.
- Changes with other pattern sizes or HDR modes.
Avoid this confusion: Assuming every deviation near the limit indicates the same problem.
Tone mapping and clipping
Tone mapping adapts content to the output range. Roll-off progressively compresses high values; clipping removes the distinction between values above a threshold. Some of this work may happen in the game and some in the display.
The combination of settings determines which details are preserved in clouds, reflections, or fire.
What to look for
- Game patterns and detail in familiar scenes.
- Monitor mode and any active conversions.
Avoid this confusion: Changing several controls at once and attributing all improvement to peak nits.
Applying it to your monitor
Check the monitor's HDR mode and the display selected in Windows. Adjusting SDR desktop comfort is different from setting a game's HDR maximum. A “Peak” or “True Black” name does not replace comparing the modes.
The path in Windows
Open Settings → System → Display. If you use multiple monitors, select the one you want to configure before opening HDR.
Illustration of the path, not a system screenshot. Layout and names may vary by Windows version. Microsoft reference ↗︎
Monitor HDR modes
Some OLEDs include modes called True Black 400 or Peak 1000. These are examples of menu names, not two universal categories for all OLEDs. Their response depends on the model and firmware.
A mode can achieve more brightness in small highlights while displaying darker midtones in another scene.
What to look for
- Mode comparisons for the specific model.
- Sustained brightness, EOTF, and scene changes.
Avoid this confusion: Claiming that a mode is always more accurate or brighter because of its name.
The SDR desktop inside HDR
Windows combines SDR and HDR content and offers an SDR content brightness adjustment. Desktop appearance is not a complete test of the monitor's HDR reproduction.
You can separate desktop comfort from HDR content calibration. Whether to leave HDR enabled or toggle it depends on your hardware, applications, and preferences.
What to look for
- The correct display and selected picture mode.
- Applications that respond to the change and the game's own controls.
Avoid this confusion: Trying to fix an SDR window's brightness by changing a game's HDR peak.
From the example to your screen
To configure your system, follow the Windows HDR guide. To evaluate a model, see its measurements or use the monitor comparison tool.
The illustrations explain concepts; they do not make this page an HDR test or replace each monitor's measurements.