Dustin Hoffman expressed some disappointment with the film. He felt it wasn't yet ready to be released when it was. There were many more issues that needed to be addressed, but they didn't have the time to cover them all. They had to deliver what they had, for the release date, which he felt was an incomplete film.
The film was shot in warehouses with specially constructed water tanks, rather than being filmed on the high seas because Warner Bros. didn't want to repeat the debacle of Waterworld (1995). Filming it on the ocean, would have sent the budget into the stratosphere, which is what crippled Waterworld's chances at the box-office. They managed to trim the budget by twenty million dollars, but despite all their precautions, Sphere (1998) still died a quiet death at the box-office.
The jellyfish attack sequence used a combination of puppets, computer graphics imagery, and footage of real jellyfish, filmed at a nearby aquarium. The footage of real jellyfish was played at three to five times its normal speed, to make the jellyfish appear more aggressive.
In the book, the sphere was supposed to be visualized as a "chrome colored ball bearing" with "grooved convolutions" that acted as a door opening so that people could enter. The movie originally had planned to use a sphere that had the same qualities (chrome ball bearing) but soon found out that if it was placed in a dark room, the reflection would look almost entirely black and not as impressive. The special effects designer and director eventually decided to go with a "champagne" colored sphere due to how it looked on screen.
The Navy men subplot, that was featured in the book, was slated to be included in the film as well. The original script had Norman talking to three mysterious men, appearing abruptly without explanation, who promised to rescue them. While Norman was talking to them, the Navy men faded out and finally disappeared. Apparently, this was another manifestation caused by the Sphere's powers. This scene was streamlined for the final shooting script by having Norman simply waking up and realizing that the Navy men were just a dream. The subplot was dropped from the finished film.
Sharon Stone and Peter Coyote both starred in movies released in 1992, which had an erotic nature. Stone in "Basic Instinct", and Coyote in "Bitter Moon". Incidentally, like Sphere (1998), the latter movie was set at sea, and both are adapted from novels, "Sphere" by Michael Crichton and "Lunes de Fiel" by Pascal Bruckner. What's more, "Basic Instinct" and "Bitter Moon" (in flashback sequences) take place in cities with world famous landmarks, which are San Francisco with The Golden Gate Bridge, and Paris with the Eiffel Tower.
Order, and reason, in which people enter the sphere in the movie: 1.) Harry - Mainly from curiosity. 2.) Norman - Accidentally while tending to an unconscious Harry. 3.) Beth - To spite Norman, and out of curiosity. Reason which people enter the sphere in the book: 1.) Beth - Presumably just to gain power over the men on the crew. 2.) Harry - From curiosity. 3.) Norman - Specifically to gain "the power" to combat Harry and Beth. Harry enters the sphere first in the book as well, followed by Beth and lastly by Norman.
Originally, the special code that Harry used, to make contact with Jerry, would be comprehensible only to him . Therefore, Harry would have the exclusive privilege of typing questions and answers . This was changed for the film, and consequently all the crew were able to communicate with Jerry. However, the original conception would account for the discrepancy in the code, since Harry's mind projected on the computer screen whatever he wanted to see.
Beth was totally distrustful of Captain Barnes in the early stages of scripting. She believed that he was responsible for their predicament. In a critical flooding scene, Beth intentionally locked Barnes inside a tank, and left him there to drown. In the final script, this subplot was scrapped, and the death of Barnes was altered to an accident, with no involvement from Beth.
Total body count in the movie - four. Barnes - Cut in half by the closing door. Ted - Burned by the fire during the giant squid attack. Teeny - Killed by attacking jellyfish. Edmunds - Pulverized by the giant squid. Total body count in the book - six. Ted - Killed by the tentacles of the squid. Barnes - Killed by the giant squid, after trying to kill the squid himself. Teeny, Edmunds, and Tina Chan (not in movie), Rose Levy (not in movie).