Then, try setting it to 0? I'm pretty sure there's a way to turn it completely off. --- 2% of GameFAQs users have this in their signature. If you're one of the 98% that doesn't, copy and paste this into your signature.
Dude, I know exactly how to get rid of the slight movement inside the dead box, go to options, controller sensitivity, then change horizontal and vertical view to 1. Then the game will play more like cod for example, no more motion sickness