Things You'll Need
Instructions
Download DIRT HDR Tweaker from Games.Softpedia.com and unzip the file. When asked where to unzip the file, point the unzip tool to the DIRT installation directory ("C:\Program Files\Codemasters\DIRT"). Navigate to the DIRT installation directory then double-click on the .exe file to open HDR Tweaker.
Click on the "File" menu then select "Backup Files," just in case something goes wrong and you have to restore from the default files. Move the slider all the way to the left, at "0.0," to completely disable bloom, then click on "Apply" or "OK."
Start the game to confirm that the lighting effect has been disabled. You can play with the slider to minimize the effect rather than completely disable it.