Free, open source, works on any GPU. A single app that replaces Night Light, f.lux, VibranceGUI and a trip into the NVIDIA control panel: warm your screen at night, lift crushed blacks in a dark game, boost saturation, switch resolution and refresh rate, and bind it all to a hotkey.
Download for Windows · macOS · Linux · Features · FAQ · Build from source
Lumen is a ground-up rework of a small Windows-only gamma tool. It keeps the original idea, quickly nudging your display's gamma, and grows it into a proper cross-platform utility.
- Three controls, not one. Gamma (contrast and midtones), brightness (output scale) and colour temperature, 3000K to 10000K, like Night Light or f.lux.
- Digital vibrance. VibranceGUI-style saturation control, 0 to 200% where 100% is neutral and 200% is the maximum GPU boost. NVAPI on Windows,
nvidia-settingson Linux. - Resolution and refresh rate switching. Searchable picker for any mode, separate Default / Stretch / Center scaling, and a confirm-or-auto-revert safety net.
- Per-app game profiles. Add a process, with a built-in explorer to pick from running apps, and Lumen applies its vibrance and optional resolution when the game launches, then restores your desktop when it closes.
- Live preview. A gradient bar shows the exact effect before it hits your eyes.
- Presets. Night, Reading, Normal, Vivid, Gaming and Movie, one click each, plus a copy in the tray menu.
- Global hotkeys. Bind keyboard combos or mouse buttons, including Mouse 4 and 5, to toggle a profile and back.
- Day / night scheduler. Switch profiles automatically at the times you set.
- Launch at startup. One toggle, or an installer checkbox. Per-user, no admin or root needed.
- Polished UI. Frameless window, sidebar navigation, a glowing circular gamma dial, gradient sliders, animated transitions and five accent themes.
| Lumen | Windows Night Light | f.lux | VibranceGUI | GPU control panel | |
|---|---|---|---|---|---|
| Colour temperature | Yes | Yes | Yes | No | Partly |
| Gamma / midtones | Yes | No | No | No | Yes |
| Software brightness | Yes | No | No | No | Partly |
| Digital vibrance | NVIDIA | No | No | NVIDIA | Vendor only |
| Per-game profiles | Yes | No | No | Yes | Vendor only |
| Resolution + refresh switching | Windows, Linux | No | No | No | Yes |
| Hotkeys, incl. mouse buttons | Yes | No | Partly | No | No |
| Runs on macOS and Linux | Yes | No | Yes | No | No |
| Open source | MIT | No | No | Yes | No |
Lumen talks to the operating system's gamma ramp APIs, not a vendor SDK, so it is GPU agnostic. NVIDIA, AMD and Intel all work the same way.
| Platform | Backend | Notes |
|---|---|---|
| Windows | GDI SetDeviceGammaRamp |
Full per-channel ramp. |
| macOS | CoreGraphics CGSetDisplayTransferByTable |
Full ramp on Apple Silicon and Intel. |
| Linux | X11 XRandR via ctypes, xrandr CLI fallback |
Full ramp on X11. Wayland uses the fallback where available. |
Some laptop panels and a few drivers refuse hardware gamma ramps. That is a driver limitation. On Windows, running as Administrator can help.
Vibrance and resolution: digital vibrance needs a vendor colour API, NVAPI on Windows or nvidia-settings on Linux. AMD and macOS are not covered yet and the control hides itself when unavailable. Resolution switching works on Windows and on Linux via xrandr.
- Download
LumenSetup.exefrom Releases. - Run it. Tick Launch Lumen automatically when Windows starts if you want autostart.
Or run the portable Lumen.exe, no installation required.
Lumen is not code signed, so SmartScreen may warn about an unrecognised app. Download only from this repository's releases.
- Download
Lumen.dmg, open it, drag Lumen to Applications. - First launch: right click, Open, since the build is unsigned. Enable autostart from Settings → Launch at system startup.
Download lumen-linux-x86_64.tar.gz, extract, then:
./installer/linux/install.sh # install for current user
./installer/linux/install.sh --autostart # install and launch at loginNeeds an X11 session for full gamma ramps (libX11, libXrandr). Global hotkeys need elevated permissions on Linux.
- Control — pick a display, drag Gamma / Brightness / Temperature, or hit a preset. Apply to all monitors in Settings fans changes out to every screen.
- Hotkeys — choose Keyboard or Mouse, set the target gamma, brightness and K, click Record Hotkey, then press your combo or click a button. Triggering it toggles the profile, triggering again returns to neutral.
- Schedule — turn on day/night and set profiles and times.
- Settings — autostart, restore on exit, keep on top, start minimised, smooth transitions and accent colour.
Settings live in:
- Windows
%APPDATA%\Lumen\settings.json - macOS
~/Library/Application Support/Lumen/settings.json - Linux
~/.config/lumen/settings.json
Yes, for gamma, brightness and colour temperature. Those go through the OS gamma ramp, which every GPU supports. Digital vibrance is the exception: it needs a vendor colour API, so it is NVIDIA only for now and the control hides itself otherwise.
No. Setting a gamma ramp writes a lookup table once, then the display pipeline applies it. There is no per-frame work and no overlay.
For colour temperature, yes, and it adds gamma, brightness, vibrance, resolution switching and per-game profiles on top. Run one of them, not both, or the two will fight over the same ramp.
Some games and anti-cheats reset the gamma ramp on launch, and some fullscreen exclusive modes take over the ramp entirely. Per-app game profiles exist for this: they reapply when the process appears. Borderless or windowed mode is the reliable case.
Partly. Wayland does not expose the X11 ramp API, so Lumen falls back to xrandr where a compatible layer is available. X11 is the supported path today.
No. Brightness in Lumen is a software output scale on the ramp, which is why it works on desktops and external monitors. It does not drive a laptop's hardware backlight or DDC/CI.
Yes. Pick a display per adjustment, or turn on Apply to all monitors.
Installation and autostart are per-user, no admin or root. Admin is only ever useful on Windows when a driver refuses ramps. Everything runs locally, there is no telemetry and no network access.
git clone https://github.com/JirkaachS/Lumen
cd Lumen
pip install -r requirements.txt
python -m lumen # run directly
pip install pyinstaller
python scripts/build.py # standalone bundle for the current OS, into dist/
iscc installer/windows/lumen.iss # Windows installer, needs Inno SetupPython with CustomTkinter for the UI, pystray for the tray, keyboard and mouse for global hotkeys on Windows and Linux, and a per-platform backend module under lumen/backends/.
Issues and pull requests are welcome, especially AMD vibrance support, Wayland ramps and DDC/CI backlight control. Open an issue first for anything large.
MIT © JirkaachS
Also useful if you searched for: monitor gamma tool, screen brightness software for desktop PC, colour temperature app, blue light filter for Windows 11, f.lux alternative, VibranceGUI alternative for Windows 11, digital vibrance without NVIDIA Control Panel, redshift GUI for Linux, refresh rate switcher, per game resolution switcher, night mode for macOS.