public float speed = 3f;
public float mouseSensitivity = 5.0f;
verticalRotation -= Input.GetAxis(“Mouse Y”) * mouseSensitivity;
Camera.main.transform.localRotation = Quaternion.Slerp (Camera.main.transform.localRotation, Quaternion.Euler(verticalRotation, 0, 0), Time.deltaTime * speed);
Just change the ‘speed’ variable as you need to control how quickly the rotation reaches its destination.