This ReShade was made from the ground up with Immersive Lighting, with the main goal of being lightweight and accessible. The intention was to focus on enhancing the already present, and pleasant visuals of Immersive Lighting. Softening colours, such as the sky and vegetation, whilst brightening and enhancing the visual fidelity overall. All while being non-intensive on your performance.

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Installation! 
- Download version 4.5.2 of Reshade, or current version of reshade.
- Uncheck all shaders when asked! Otherwise you'll get a hefty loading time, everytime you launch the game.
- Locate your bin/x64 folder; found here (C:\Program Files (x86)\Steam\steamapps\common\The Witcher 3\bin)
- Drag and drop my reshade-shaders and Escape.ini in. Replace any files if prompted.
- Launch the game for the first time and open Reshade with either Home or Shift+F2 (Depends on which version you use)
- Click the down arrow in the Home tab, and enable Escape.ini. (Dont forget to activate performance mode!)

Performance Cost: 
Roughly 8-10 FPS

In-Game Settings:
- Sharpening: Low
- Motion blur: OFF
- Vignette: OFF
- Chromatic Abberation: OFF
- Depth of Field: Optional (If you do wish to have it OFF, I recommend this Mod, which keeps DoF on in cutscenes, but off for gameplay.)

Notes: If you find the colors overbearing or too much, I recommend turning off or tweaking the Vibrance filter.
This reshade is not made for Toussaint, and I don't recommend using it for Blood and Wine; try out Verona or Serenity instead!

And you're done!

Update Log:
V1.0: Uploaded on 15th of January 2020.

V1.1: Uploaded on 13 of April 2020; 
Lowered the overall saturation considerably, no longer nearly as blue, and green. Dark areas are now actually dark, instead of artificially lit with a hazy purple. Adjusted blur that encompassed everything, image quality should be clearer. (Also managed to drop performance cost by about 4-5 frames.)

V1.2: Uploaded on 26th of April 2020;
Desaturated the colours further, skies have a soft blue and white hue. Ground, grass and trees are a lighter shade of green. (Once again managed to save 1-2 frames.)

Disclaimer;
Screenshots are almost entirely unedited, DoF, Letterboxing & Vignette were used to make a more cinematic shot. 

-Thanks to sanul17 from the GM Server for helping with this!

Link to the Gudmods Discord Server