The center of the optical sight below the center of sight. Whenever I line up my actions relative to the center of focus (point on the screen) applicable to the object / target, the action is an adventure on an iron sight, or on an optical sight, focuses the center of the sight well below the object / target. This is inconvenient in twins, when using an optical sight with a high magnification - the target is beyond the scope of the optical review.
Exit from the action "sight" has the same effect, the focus of view remains above the object / goal.
According to the sensations in the game, the aiming process occurs without tactility. When I want to look through the sight of a weapon, I do not lift a weapon to the head and eye lines, but lower my head to the weapon and the line of the optical center, losing the objective / object of observation from view.