text: There was an example of this on a tv show few years back where they put up a 6 foot fake monster in the dark on the side of the road and asked them what they saw. The descriptions varied from like 10-20 feet, teeth and movement exaggerations, even adding wings and glowing eyes. 
  
  It's due to the fight/flight mode, you really have to be trained or train yourself to concentrate on details in a sudden/frightening situation.