Sikkmod is a general enhancement mod for id Software's 2004 FPS: Doom 3 and its expansion pack: Resurrection of Evil. Its main purposes are to update visuals of Doom 3 to a more modern level and to allow the user to customize various aspects of the game to suit their preferred styles all while maintaining the core mechanics and aesthetics originally put in by id Software. The mod also includes a number of fixes to and better organization of stock files in order to create a clean and more stable base for future mods
Random screenshots from Resurrection of Evil...
I downloaded it .. not everything works so well as here
You need to tweak the mod options the default ones don't work the same for all, for example to me it made the game dark for others they made the game bright, just spend some time on the mod menu changing values and you will be surprised.
I am not so fond of the brown filter honestly. :/