It's among the list of graphical features you can tag on or off at the buttom of the graphics options (in the game, of course). It's there along with Depth of Field.. and 2 other options I can't remember atm.
The HDR part is basically my whole point of the post so I'm not surprised you're not yet excited if you haven't found the option yet to disable it in the first place. Give the options another look, let me know if it helped!
