The miniature stormy ocean is extremely well realised by Fred Sersen and crew. Particularly noteworthy is the camera which has the point of view of being mounted on the fishing boat with the realistic motion of being tossed about by the chaotic waves. This imparts a visceral sense of realism to the miniature shots.
I have recently found a better copy on youtube and have replaced the original pictures which were from a NTSC VHS to DVD dub from an Ebay vendor with the better resolution frame grabs.