LG OLED C1/C2 RGB Range Washed Out: Match Full and Limited

Quick Answer

If black looks gray or shadows disappear on an LG C1/C2 connected to a PC or console, match the source's RGB/video range to the television's interpretation. Use Auto at both ends first. For a controlled manual test, set both ends to Full or both to Limited and verify with a trusted black-clipping pattern. Full is not inherently higher quality; a matched Limited chain can reproduce video correctly.

Do not raise or lower the TV's black-level control by eye until letterbox bars “look right.” A mismatch can make Full data interpreted as Limited appear washed out, or Limited interpreted as Full crush near-black detail. Fix the signaling pair before HDR tone mapping, color, brightness or calibration.

Symptoms of a Range Mismatch

OLED black and letterbox bars appear gray only on one HDMI source.

Dark detail is missing even though midtones and highlights look plausible.

Switching NVIDIA/AMD Output Dynamic Range immediately changes the black floor.

An internal LG app looks correct while the PC version is washed out.

A black-clipping pattern either shows every below-black patch or hides several intended above-black steps.

Desktop screenshots look correct on another display, while the HDMI presentation does not.

HDR and SDR behave differently because the source selects different range/format states.

Windows HDR desktop looks pale even with matched range. That may be SDR-in-HDR mapping, a separate issue.

Use a known local test pattern or platform calibration—not a compressed social image whose levels may be changed by browser/video processing.

Causes: Full and Limited Are Code Conventions

In an 8-bit representation, video Limited commonly reserves nominal code values around 16–235 for visible black-to-white, while RGB Full uses the wider 0–255 range. Higher bit depths scale the convention. Both can describe correct pictures when source and display agree.

When a Limited signal is treated as Full, nominal black is mapped above display black and shadows can be compressed incorrectly. When Full is treated as Limited, values near black/white can clip or remap. Labels are confusing: older LG menus may say Low/High, newer firmware may say Limited/Full/Auto. Use the on-screen description and pattern.

Chroma 4:4:4 versus 4:2:2 is separate. Chroma affects color resolution; range affects level interpretation. Bit depth is also separate. Changing all three at once hides the cause.

Step-by-Step Range Diagnosis

1. Establish one signal context

Choose SDR desktop or SDR video first. Record TV input, PC/console output, picture mode and whether the input is labeled PC. Reset only the affected picture mode. Disable Dynamic Contrast and Black Stabilizer during the test.

HDR10 and Dolby Vision load other contexts; do not use their result to judge SDR.

2. Compare an internal app

Play the same title/frame internally and from the external source. Correct internal black plus gray HDMI black points toward source range or receiver conversion. If both are identical, title mastering or room reflection is more likely.

3. Use a proper clipping pattern

Display a trusted SDR black-level pattern through the exact source. Darken the room enough to see near-black without reflections. Reference black should remain black; intended above-black patches should barely separate. Below-black values are not supposed to become ordinary picture detail.

Do not use a browser screenshot unless the pattern provider confirms browser-safe levels.

4. Start with Auto

Set source and LG range to Auto. Restart the playback app or HDMI output so metadata is renegotiated. Many consoles correctly signal range automatically. If the result is correct, keep Auto; manually forcing Full offers no benefit.

5. Test a known pair

On NVIDIA, use Change Resolution/Output Dynamic Range. On AMD, inspect Pixel Format and the RGB Full/Limited choice exposed by current Adrenalin software. Set the LG counterpart according to its description. Compare Full+Full and Limited+Limited, never Full at one end and Limited at the other.

On Xbox/PS5, use Auto first and verify platform calibration. Do not assume console “PC RGB” is better for video apps.

6. Remove intermediaries

Connect PC/console directly to TV. An AVR, capture card or converter can modify EDID or output format. If direct is correct, reinsert the device and inspect its video-range setting. Avoid “enhanced black” controls that change levels without clear documentation.

7. Verify white clipping and color

A range mismatch affects both ends of the scale. Use a suitable white pattern after black is correct. Then verify colored desktop text/chroma separately. Do not alter white balance/CMS to compensate for range.

NVIDIA, AMD and Console Caveats

NVIDIA settings can change when resolution is selected under a TV section versus PC section or after driver updates. Confirm active resolution/format rather than assuming a saved control persisted.

AMD names can vary by driver and display capability. Pixel Format choices combine chroma and range; read the complete label. Use a supported 4K120 combination within HDMI bandwidth.

Consoles may use Limited for video and Auto for games. Their system calibration assumes the chosen range. A game-specific brightness slider should be adjusted only after the chain matches.

C1/G1 use 2021 webOS organization; C2/G2 use 2022. The black-level item can be disabled or automatic in some HDR/PC modes. A grayed control often means the TV follows signaled range.

The PC input type helps preserve 4:4:4 but does not excuse mismatched levels. Dolby Vision uses its own pipeline and should remain on its intended automatic behavior unless authoritative device documentation says otherwise.