A photographer who specializes in making ferrotype photographs, or the equipment used to produce ferrotypes.
From 'ferrotype' + '-er' (agent noun suffix). This occupational term was common in the 19th century when ferrotypes were the dominant form of affordable photography.
A ferrotyper was essentially a 19th-century portrait photographer—they'd set up shops in towns and cities offering quick, cheap ferrotype portraits for working-class people who couldn't afford more expensive photographic methods.
Complete word intelligence in one call. Free tier — 50 lookups/day.