In this mod is a ppFilter and two required .ini-files. You don't have to use the ppFilter, but it is recommended.
There is no huge difference, but the colors are a little bit more powerful & realistic than the default settings.
Tested Assetto Corsa Version: 1.14.4
How to install:
Download the .zip-File and unzip it. Go to the folder "AGO_1.0" and copy the folders "cfg" and "system" into your Assetto Corsa directory (Allow to replace the previous file). (I also added the default file, if you do not like the AGO.)