question: Was M1 's cinematographer a person whose employer produced M2
query: SELECT count(*) WHERE {
  ?x0 a ns:people.person .
  ?x0 ns:film.cinematographer.film M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company ?x1 .
  ?x1 ns:film.producer.film|ns:film.production_company.films M2
  }