William Hurt was offered the role of Dr. Grant, but turned it down without reading the book or the script.
Harrison Ford turned down the male lead.
Richard Attenborough's first acting role in 15 years.
Michael Crichton's agents circulated the book to six studios and directors. Warner Brothers wanted it for Tim Burton to direct while Columbia was planning it for Richard Donner. Fox was also interested and was intending the project for Joe Dante, while Universal wanted 'Steven Spielberg' to direct. Crichton was reluctant to submit to a bidding war, He instructed his agents to put a set price on the film rights and he could decide who was more likely to actually get the film made. After interviewing all the prospective directors, he agreed to sell the rights to Universal and Steven Spielberg, who was already his first choice.
In Michael Crichton's novel, John Hammond proudly says that the narrator on the prerecorded park tour is Richard Kiley. Later, Kiley was hired to play himself in that role for the movie; possibly the only instance of a celebrity appearing in a book, and then later cast as him or herself in the film version.
The glass of water sitting on the dash of the Ford Explorer was made to ripple using a guitar string that was attached to the underside of the dash beneath the glass.
Director Steven Spielberg was worried that computer graphics meant Nintendo type cartoon quality. He originally only wanted the herd of gallimimus dinosaurs to be computer-generated, but upon seeing ILM's demo animation of a T-rex chasing a herd of galamides across his ranch, he decided to shoot nearly all the dinosaur scenes using this method. The animation was first plotted on an Amiga Toaster, and rendered for the film by Silicon Graphics' Indigo workstations.
Generally speaking, any shot of a full dinosaur was computer-generated, but shots of parts of dinosaurs were of animatronics.
The full-sized animatron of the tyrannosaurus rex weighed about 13,000 to 15,000 pounds. During the shooting of the initial T-rex attack scene that took place in a downpour and was shot on a soundstage, the latex that covered the T-rex puppet absorbed great amounts of water, making it much heavier and harder to control. Technicians worked throughout the night with blow driers trying to dry the latex out. Eventually, they suspended a platform above the T-rex, out of camera range, to keep the water off it during filming.
A baby triceratops was built for a scene where one of the kids rides it. Special effects technicians worked on this effect for a year but the scene was cut at the last minute as Steven Spielberg thought it would ruin the pacing of the film.
The park software is written in Pascal; a program is clearly visible in one of the monitor close-ups on the UNIX system. The graphical interface recognized as a UNIX system was a fictional Silicon Graphics 3D File System Navigator, a real-life version of which was later written in response to the film. The version number of the Silicon Graphics UNIX Operating System is 4.0.5 and is visible in one of the close-ups in the operating system's shell window (command program).
In the egg-hatching scene, a new-born baby triceratops was originally supposed to come out of the egg, but it was changed to a velociraptor.
There were so many wires and rigging to control the velociraptor animatrons in the kitchen stalking scene that the child actors had to literally step over and around them while the scene was being filmed. The kitchen set was greatly expanded from the original design to accommodate the velociraptors. Some reports say that all of the dinosaurs in the kitchen scene were computer-generated.
Many errors were corrected digitally: some stunt people were made to look like the actors, and in one scene an entire Ford Explorer was digitally generated.
The first film to use DTS digital surround sound.
To study the movement of the Gallimimus herd, the film's digital artists were ordered to run along a stretch of road with some obstacles, their hands next to their chest.
At one point Lex is hanging from a floorboard between stories. She looks up for a moment. The stunt double looked up accidentally while filming and Ariana Richards' face had to be superimposed in post production.
Fred Sorenson was the pilot who flew the crew off Kauai when the hurricane hit during production. He played Jock, the pilot who flew Indiana Jones away in the opening scene of Raiders of the Lost Ark (1981), also directed by Steven Spielberg.
In this film, Steven Spielberg directs the man who beat him to the Best Director Oscar in 1983 (Richard Attenborough, whose film Gandhi (1982) also beat Spielberg's E.T.: The Extra-Terrestrial (1982) as Best Picture).
The computer in the back of the computer room with the many (65536) red LEDs is actually a real computer: The Connection Machine CM-5 made by Thinking Machines. It contained many SPARC 2 RISC processors and the LEDs were added to make the machine more aesthetically pleasing than their previous models. Unfortunately, it was not actually a very good supercomputer and the company failed not long afterward. The comment about networking eight connection machines is pretty superfluous as they were meant to be used like this. The bigger problem was writing programs that efficiently mapped onto the data parallel architecture.