Reduced clause

  1. The boy who (took)/(takes) the picture is one of my friends.
  2. The boy who is taking the picture is one of my friends.
  3. The boy taken the picture is one of my friends. (=Reduced clause)
  4. The boy taking the picture is one of my friends. (=Reduced clause)
    Please correct and comment.
    Thanks.

3 is incorrect.