How to check near-black detail after switching HDR

After switching HDR on or off, dark areas in a game, video, or desktop may look crushed, washed out, or nearly unchanged. It can be hard to tell whether the mode changed the display, a setting is interfering, or the content itself is simply dark.

Compare the same dark shades in both modes with the Display Test. This can help you spot changes in near-black detail, but it cannot certify HDR performance: a browser test may show SDR content even when HDR is enabled.

Compare near-black detail in both modes

1. Open the Display Test on the screen you want to check. If you have more than one screen, make sure the test is on the display whose HDR mode you changed.
2. Use the test's color patterns and look at the darkest gray shades. Check whether neighboring dark shades are distinguishable, especially near the edges of black areas.
3. Note what you see, then turn HDR off or on in your system display settings. Keep brightness and room lighting the same for the comparison.
4. Reload the test after changing modes and inspect the same dark patterns again. Give your eyes a moment to adjust, and avoid switching back and forth quickly.
5. Repeat the comparison in the app or video where you first noticed the problem. A browser pattern and HDR video do not necessarily use the same display path.

Do not judge the screen from a phone photo. A camera may change exposure, contrast, and color, making dark shades appear different from what you see in person.

What the result means

Dark shades look distinct in both modes

The display can show some separation in the test pattern, and the mode change did not obviously hide those shades in the browser. If a particular movie or game still loses detail, check its HDR setting, brightness controls, and the way it handles dark scenes. A browser result does not guarantee that HDR content is mapped correctly.

Several dark shades merge into black in one mode

The mode change affects how dark content appears, but the test alone cannot identify whether the cause is the display, graphics output, or system tone mapping. Check that you selected the right screen and that settings such as Night Light or a monitor's black-level control did not change between comparisons.

Dark shades look raised or gray

Black may be displayed as gray because of a brightness, contrast, or black-level setting, or because the screen is in a different picture mode. Compare the same pattern in the same room and inspect the monitor's own controls before deciding that the panel is faulty.

The browser test looks similar, but HDR video does not

That can be normal. The test may be rendered as standard dynamic range, or SDR, which does not exercise the full HDR signal path. Use the browser pattern to check general dark-shade visibility, then use a known HDR video or game to assess that app's HDR behavior.

The result changes each time you look

Ambient light, screen brightness, adaptive display features, and your eyes adjusting to the room can all affect the comparison. Repeat it under steady conditions before treating a small change as a fault.

How to fix it

1. Keep the comparison conditions steady. Use the same screen brightness, room lighting, viewing angle, and test page in both modes. Turn off automatic brightness or adaptive brightness temporarily if it changes the screen during the comparison.
2. Check the HDR switch for the correct display. In Windows 11, open Settings › System › Display › HDR and confirm the selected display and HDR setting. On macOS, open System Settings › Displays, select the display, and check whether an HDR option is available. The option depends on the display and connection.
3. Turn off screen filters while testing. In Windows 11, check Settings › System › Display › Night light. On macOS, check System Settings › Displays for Night Shift and True Tone, when available. These features can alter the screen's appearance, so keep them in the same state for both comparisons.
4. Check the monitor's picture settings. Use the monitor's physical controls to review its picture preset, brightness, contrast, and black-level setting. A reset to the monitor's default picture mode can be a useful comparison, but note the original values first.
5. Reconnect or change the display connection. If you use an external monitor, reseat the cable and try another port or a direct connection instead of a dock. Some adapters and connection settings limit which display modes are available.
6. Restart the app or computer. A game or video player may not apply a changed HDR mode until it restarts. If the issue persists across apps, restart the computer and repeat the comparison.

When the display may be the problem

If the same dark shades remain merged in several sources, modes, and connections, the display may have limited shadow detail or a hardware fault. Check another input or device, and review the monitor's support or return options if it is new. A browser color pattern can reveal a visible problem, but it cannot determine whether the panel meets a particular HDR specification.

Why an HDR switch may not change a browser pattern

HDR describes a wider range of brightness and color than standard dynamic range. Turning HDR on changes the operating system's display pipeline, but an ordinary web page is not automatically HDR content. The system may continue to display the page as SDR while handling HDR video or games differently. For that reason, use the Display Test to compare general screen behavior, not as a final HDR certification test.

For a more controlled dark-room comparison, also keep the room lights consistent, as explained in how to compare screen contrast with room lights off.