Special effects work continued on the film, with Tippett's unit adjusting to new technology with Dinosaur Input Devices:[33] models which fed information into the computers to allow themselves to animate the characters traditionally. In addition, they acted out scenes with the raptors and Gallimimus. As well as the computer-generated dinosaurs, ILM also created elements such as water splashing and digital face replacement for Ariana Richards' stunt double.[9] Compositing the dinosaurs onto the live action scenes took around an hour. Rendering the dinosaurs often took two to four hours per frame, and rendering the T. rex in the rain even took six hours per frame.[34] Spielberg monitored their progress from Poland during the filming of Schindler's List,[35] having teleconferences four times a week with ILM's crew. The director described working simultaneously in two vastly different productions as "a bipolar experience", where he used "every ounce of intuition on Schindler's List and every ounce of craft in Jurassic Park".[36]
Along with the digital effects, Spielberg wanted the film to be the first with digital sound. He funded the creation of DTS, which would allow audiences to "really hear the movie the way it was intended to be heard". [36] The sound effects crew, supervised by George Lucas,[37] were finished by the end of April.[38] Sound designer Gary Rydstrom considered it a fun process, given the film had all kinds of noise - animal sounds, rain, gunshots, car crashes - and at times no music. During the process, Spielberg would fly during weekends from Poland to Paris, where he would meet Rydstrom to see the sound progress.[36] Jurassic Park was finally completed on May 28, 1993.[38]