It's based on an excellent book, of the same title. The book delves into the social structure of Nantucket society and the whaleship crews, the personal backgrounds of many of the officers and men, and the details of the whaling business.

I don't remember if the film showed this, but the captain had to go home and tell his sister they ate her son, his nephew. It was second disastrous voyage, if I remember correctly, and it was the end of his career. No one would risk a whaling ship under him again.