Final answer:
Edwin S. Porter was the key director/cameraman for Edison Co, known for directing the early influential film, The Great Train Robbery, in 1903.
Step-by-step explanation:
The most important director/cameraman for Edison Co was Edwin S. Porter. Thomas Edison's studios produced numerous silent short films in the early 20th century. One notable example is The Great Train Robbery, an action picture directed by Edwin S. Porter in 1903. This film, just over eleven minutes long and based on a stage play, is recognized as one of the early films featuring trains and is an important work in the history of cinema.