• purpose: stop lg ultragear gaming monitors from dimming under static or semi-static content by constraining the panel's effective luminance range.
• method: apply and set a custom icc/icm color profile that limits the tone response so the monitor's firmware auto-dimming heuristic doesn't trigger.
• platform: windows 10/11 using windows color system (wcs).

• many ultragear models dim when average picture level stays high or content looks static.
• a tailored color profile reduces the effective range windows drives the display through, preventing the firmware condition that triggers dimming.
• software-only mitigation: nothing on the monitor is flashed or permanently changed; you can revert at any time.

limitations of other approaches

• disabling power-saving, abl or similar osd options often does not fully disable dimming on ultragear models.
• changing windows/gpu settings (disabling adaptive brightness, cabc, toggling hdr, etc.) commonly fails to stop the firmware-level behavior.
• firmware updates would be ideal, but many screens either have no user-feasible updates or the update tools are not publicly available. the profile-based approach works immediately without firmware changes.

• lg-ultragear-full-cal.icm — custom icc/icm profile that constrains luminance.
• install-lg-ultragear-no-dimming.ps1 — installer that finds "lg ultragear" displays, installs the profile, associates it, and sets it as default.
• install-full-auto.bat — one‑click bridge: auto‑elevates, uses a temporary execution policy bypass, and runs the installer end‑to‑end.
• release artifacts — packaged zip and a single‑file executable built from the installer for easy distribution.
• scripts/ — helper scripts:
  • scripts/local-ci.ps1 — run format, lint, test, build locally (skips steps if tools not installed)
  • scripts/clean.ps1 — clean common build/test artifacts (dist, logs, coverage, etc.)
  • scripts/embedder.ps1 — regenerate and embed the profile (Base64 + SHA256) into the installer

option a - one-click batch (recommended)

• double-click install-full-auto.bat (or run from command prompt). it will:
  • request admin (uac),
  • run powershell with -executionpolicy bypass (no permanent policy change),
  • call the installer with defaults.
  • at the end, it will prompt: "press enter to exit...".

option b - powershell (manual)

• open powershell in the repo folder, then run:

  Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass -Force
  ./install-lg-ultragear-no-dimming.ps1

  • the installer auto‑elevates if needed and, by default, prompts: "press enter to exit...". add -NoPrompt to skip.
  • tip: you can probe first with:

  ./install-lg-ultragear-no-dimming.ps1 -Probe

option c - single executable (no powershell needed)

• download install-lg-ultragear-no-dimming.exe from the releases page and run it (uac prompt will appear). it behaves like the powershell script and will prompt to press enter at the end.

  note: when using the executable, open powershell as administrator and run it from your downloads folder so elevation works reliably:

  # start powershell as administrator, then:
  cd $env:USERPROFILE\Downloads
  .\install-lg-ultragear-no-dimming.exe

what happens

• the profile is copied (or refreshed in‑place) into %WINDIR%\System32\spool\drivers\color.
• displays with friendly name containing "lg ultragear" are discovered via wmi.
• the profile is associated with each matched display and set as default.
• the sdr pipeline receives an explicit default association (hdr/advanced-color is also updated unless -SkipHdrAssociation).
• system color settings are refreshed.

if you prefer not to run any scripts, you can apply the profile manually using the built‑in color management tool.

pre‑requisites

• get the lg-ultragear-full-cal.icm file from this repo (clone or download the zip).

optional: copy to the system color store (admin)

• open file explorer as administrator.
• navigate to %windir%\system32\spool\drivers\color.
• copy lg-ultragear-full-cal.icm into that folder. (you can also keep the file anywhere; the ui lets you browse.)

associate the profile with your lg ultragear

• press win + r, type colorcpl, press enter.
• go to the “devices” tab.
• from the display dropdown, select your lg ultragear monitor. if you have multiple displays, ensure you select the correct one (use windows settings → system → display → “identify” to confirm which is which).
• check “use my settings for this device”.
• if lg-ultragear-full-cal.icm is not listed, click “add…”, then:
  • if you placed the file in the system store, pick it from the list; or
  • click “browse…” and select the .icm file from wherever you saved it.
• select lg-ultragear-full-cal.icm and click “set as default profile”.
• repeat for any other lg ultragear displays you want to fix.

optional: set system‑wide default (all users)

• in colorcpl, click “change system defaults…”.
• repeat the same steps under the “devices” tab for the target display(s).

finish and verify

• close the dialogs. some apps pick up changes immediately; others may need a restart or sign‑out/in.
• to verify, open colorcpl again and confirm the profile is the default for your lg ultragear.

• default: ./install-lg-ultragear-no-dimming.ps1
• match different text: ./install-lg-ultragear-no-dimming.ps1 -monitornamematch "lg"
• use a specific file: ./install-lg-ultragear-no-dimming.ps1 -profilepath ./lg-ultragear-full-cal.icm
• also associate per-user: ./install-lg-ultragear-no-dimming.ps1 -peruser
• do not set as default: ./install-lg-ultragear-no-dimming.ps1 -nosetdefault
• skip hdr association: ./install-lg-ultragear-no-dimming.ps1 -skiphdrassociation
• install only (no device association): ./install-lg-ultragear-no-dimming.ps1 -installonly
• probe only (no changes, list monitors and matches): ./install-lg-ultragear-no-dimming.ps1 -probe
• dry run (simulate actions; same as -WhatIf): ./install-lg-ultragear-no-dimming.ps1 -dryrun

console output

• the installer prints clear, colored progress with console-safe labels (e.g., [STEP], [INFO], [OK]), lists all detected monitors, and highlights which ones match the friendly-name filter (default: "lg ultragear").

• -ProfilePath <path>: path to ICC/ICM file. Default: ./lg-ultragear-full-cal.icm.
• note: the installer uses the embedded profile at runtime; the -ProfilePath argument is kept for compatibility but is ignored during install/association.
• -MonitorNameMatch <string>: substring to match monitor friendly names. Default: LG ULTRAGEAR.
• -PerUser: also associate the profile in current-user scope.
• -NoSetDefault: associate only; do not set as default.
• -SkipHdrAssociation: skip the HDR/advanced-color association API.
• -InstallOnly: install/copy the profile into the system store without associating.
• -Probe: list detected and matched monitors; no changes.
• -DryRun: simulate operations (equivalent to WhatIf for actions).
• -NoPrompt: do not wait for Enter before exiting.
• -SkipElevation: do not auto-elevate (useful for CI/testing).
• -Help (aliases: -h, -?): show usage and exit.

local dev helpers

# run all (format, lint, test, build)
pwsh -File scripts/local-ci.ps1

# treat linter warnings as errors
pwsh -File scripts/local-ci.ps1 -Strict

# clean artifacts
pwsh -File scripts/clean.ps1

# update embedded profile (base64 + sha256) inside the installer
pwsh -File scripts/embedder.ps1 -ProfilePath .\lg-ultragear-full-cal.icm

# or specify a different main script path
pwsh -File scripts/embedder.ps1 -ProfilePath C:\path\to\your.icm -MainScriptPath .\install-lg-ultragear-no-dimming.ps1

idempotency

• if the profile file is already present in the system color store, the installer compares hashes and overwrites only when content differs; no duplicate files are created.
• associations and "set default" operations are safe to repeat; the script aims to leave a single effective default profile per device.

• classic ui: press win+r, run colorcpl -> devices tab -> select your lg ultragear -> ensure lg-ultragear-full-cal.icm is present and set as default.
• settings: system -> display -> advanced display -> pick the lg; verify behavior under hdr if applicable.
• visual check: leave a bright, mostly static window; dimming should be gone or greatly reduced.

• switch back: colorcpl -> devices -> select display -> choose another default or uncheck "use my settings for this device".
• remove association: in colorcpl, select the profile and click remove.
• remove file: delete it from %windir%\system32\spool\drivers\color (admin required).

• uses wcs (mscms.dll) via p/invoke:
  • installcolorprofile to install the icc/icm (or we overwrite if already present),
  • wcsassociatecolorprofilewithdevice to bind it to the display's device key,
  • wcssetdefaultcolorprofile to make it default,
  • colorprofileadddisplayassociation best-effort for hdr/advanced-color displays.
• monitors are discovered via wmimonitorid to match user-friendly names like "lg ultragear 27gn950".
• a wm_settingchange broadcast prompts windows to refresh color.

• installing into the system color store and setting defaults requires administrator. both the batch and the powershell installer auto-elevate (uac prompt shown if needed).

• see license.md for licensing details.

• downloads & releases

• automated ci produces versioned releases named yyyy.n (example: 2025.1). n increments for each release within the year.

• each release includes:

  • lg-ultragear-dimming-fix.zip (scripts, exe, profile, readme, license)
  • install-lg-ultragear-no-dimming.exe (standalone executable)