About 13 minutes in, a keeper lights his pipe by striking a match on a matchbox. The film is set in 1801 and striking matches were not invented until 1826; they were very expensive until mass production many years later.
The Fresnel lens seen in the film was not installed until about 1817.
The costumes of the two leads don't match anything that seamen would be wearing at the time, especially the bowler hat which was invented in 1849.
The movie takes place in 1801. The light in the lighthouse is a Fresnel lens which was not used in lighthouses until 1823 and that was on the French coast.
Modern matches were not invented until 1805, and were not common place until decades later. This came after the 1801 setting of the movie.
In 1801, the lighthouse at South Bishop Island was not yet built. It was built in 1839.