стандартный скрипт в поставке юнити - SmootLookAt.cs 
 Код
 
 var target : Transform; 
 var damping = 6.0; 
 var smooth = true; 
 @script AddComponentMenu("Camera-Control/Smooth Look At") 
 function LateUpdate () { 
  if (target) { 
   if (smooth) 
   { 
    // Look at and dampen the rotation 
    var rotation = Quaternion.LookRotation(target.position - transform.position); 
    transform.rotation = Quaternion.Slerp(transform.rotation, rotation, Time.deltaTime * damping); 
   } 
   else 
   { 
    // Just lookat 
       transform.LookAt(target); 
   } 
  } 
 } 
 function Start () { 
  // Make the rigid body not change rotation 
     if (rigidbody) 
   rigidbody.freezeRotation = true; 
 }