It's very easy to find. Take your time, this guide won't be going anywhere.

1: Click on Options/Settings
2: Locate the "Video" tab
3: Click on "Advanced" (below "Adjust brightness levels" and above "3rd party technology credits)
4: Under "Motion blur," there's text above a button that says "High Dynamic Range"

You can adjust these settings to whatever you like. Some games require full, and some do not.

Image demonstration:

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