what techniques were used in the film to bring the creatures on the screen?
Computer-generated imagery (CGI), animatronics.
Jurassic Park III
As with the previous films, Industrial Light & Magic (ILM) provided dinosaurs through computer-generated imagery (CGI), while Stan Winston and his team provided animatronics.
what is compsognathus? A genus of small, bipedal, carnivorous theropod dinosaur. how does it look like? Chicken-sized, small, bipedal, long hind legs; the forelimbs were smaller than the hindlimbs; the hand bore two large, clawed digits and a third, smaller digit that may have been non-functional; delicate long narrow skull with tapered snouts. who discovered the species? Joseph Oberndorfer were there any films or literature which speaks of these species? Yes - in Children's dinosaur books, in the movie - Jurassic Park III
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Jurassic Park III [SEP] Creatures on screen
As with the previous films, Industrial Light & Magic (ILM) provided dinosaurs through computer-generated imagery (CGI), while Stan Winston and his team provided animatronics. The animatronics were more advanced than those used in previous films, and included the ability to blink, for an increased sense of realism. While animatronics were used for close-up shots, other scenes used sticks with pictures of dinosaur heads attached, as placeholders to which the actors could react. Puppeteers worked together to create the "T. rex", "Spinosaurus", and "Velociraptor" movements. Multiple puppeteers were assigned to operate different parts of each animatronic dinosaur, and in some cases it would take hours of practice for a dinosaur's puppeteers to perform in sync.