How to know when camera stops rotating using lookRotation

Im very new to unity and javascript so I shall be asking some pretty dumb questions here for awhile so bare with me :) I am writing a script to drop onto the camera and the camera rotates to look at what ever the target object is and when the camera is finished rotating to the object i want to change the followTarget var to false. But I can seem to figure a way of knowing when the camera is finished rotating correctly. . I have the below code in the LateUpdate function and it eventually hits the followTarget = false but it takes afew game loops after the camera has stopped rotating. Can anyone tell me the correct way to do this? Or explain why it takes a few update loops more then it should to hit the bool assignment?

 var smoothRotation = Quaternion.LookRotation(target.position - transform.position);
  
  transform.rotation = Quaternion.Slerp(transform.rotation, smoothRotation, Time.deltaTime * damping);
  print("smooth rotation " + smoothRotation);
  if((transform.rotation == previousRotation) && (closeEnough == true)){
  followTarget = false;
  print("follow target" + followTarget);
  }
  previousRotation = transform.rotation;