RGT Screen Dimmer & Blue Light Filter 1.4.2
=============================================

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HOW TO INSTALL
--------------
1. Unzip this folder anywhere you like (your Desktop is fine).
2. Double-click "RGT Screen Dimmer & Blue Light Filter.exe".
3. The control panel opens by itself the first time. After that, click the
   amber icon by the clock, or press Ctrl+Alt+D.

There is no installer to run. Nothing is written to your Windows folder and
nothing is added to your registry unless you tick "Start automatically when I
sign in" in Settings.

Windows may show a blue "Windows protected your PC" box the first time,
because this is a new program from a small publisher. Click "More info", then
"Run anyway". This is normal for any new app that has not yet built up a
download history with Microsoft.


TWO DIFFERENT JOBS, TWO SEPARATE CONTROLS
-----------------------------------------
These are not the same thing, and the app keeps them apart on purpose.

  A blue light FILTER changes the colour of the screen. It shifts everything
  towards warm orange, which removes the short-wavelength blue light that
  keeps you awake. It does not make the screen any darker.

  A screen DIMMER changes how much light the screen actually puts out. It
  lowers the backlight, and then keeps going with a dark layer once the
  backlight has bottomed out. It does not change the colour.

In a dark room you usually want both: warm colours so your body still thinks
it is night time, and low light output so your eyes are not being blasted.
Either one on its own only solves half the problem.


HOW TO USE IT
-------------
The app lives next to your clock, at the bottom right of the screen. Click
its amber icon to open the panel. You will see the two controls separately.

  Blue light filter   Pick a preset, or drag the strength slider. The app
                      tells you roughly how much blue light you are cutting
                      and at what colour temperature.

  Screen dimmer       One slider per screen. Drag it down past the little
                      tick mark and the screen keeps getting darker, well
                      past the lowest setting your monitor allows on its own.


KEYBOARD SHORTCUTS
------------------
  Ctrl + Alt + Up / Down    Brighter / darker
  Ctrl + Alt + D            Open the panel
  Ctrl + Alt + 0            Put everything back to normal (panic button)
  Ctrl + Alt + B            Turn the filter on or off
  Ctrl + Alt + T            Show true colours for a moment


IF THE SCREEN STAYS TINTED OR TOO DARK
---------------------------
It cannot get stuck. Two things protect you:

  * If a change makes the screen very dark, a message appears and everything
    goes back to how it was after 10 seconds unless you confirm.
  * Ctrl + Alt + 0 restores everything at any time, including the colour.

The colour shift is a display setting, so if the program is force-closed or
crashes it can be left behind. Starting it again and pressing Ctrl + Alt + 0,
or simply signing out of Windows, clears it.


IF YOUR MONITOR'S BRIGHTNESS WON'T MOVE
---------------------------------------
Some monitors do not let software control their backlight. The app notices
this and dims those screens in software instead, so it always works. If you
would rather have real backlight control, try these in order:

  1. Look in your monitor's own menu (the buttons on the monitor itself) for
     a setting called "DDC/CI" and turn it on.
  2. Connect the monitor straight to the computer rather than through a
     docking station or USB hub.
  3. Try a DisplayPort or USB-C cable instead of HDMI.

Monitors connected through DisplayLink adapters cannot be controlled this way
at all. Software dimming still works on them.


SOMETHING NOT WORKING?
----------------------
Run the app with --diag to produce a report:

    "RGT Screen Dimmer & Blue Light Filter.exe" --diag

It writes screen-dimmer-report.txt to your Desktop and opens it. Send
that file with your question and we can usually tell you what is going on.


REQUIREMENTS
------------
Windows 10 or Windows 11. Nothing else to install.


UNINSTALL
---------
Delete the .exe. If you turned on "Start automatically when I sign in",
turn it off first, or delete the "ReadyGoScreenDimmer" entry from
Task Manager's Startup tab.

Your settings live in:
  %LOCALAPPDATA%\ReadyGoTools\ScreenDimmer


readygotools.com/software/screen-dimmer-blue-light-filter/
