Showscan is a cinematic process developed by Douglas Trumbull. Similar to 70 mm wide-screen processes, it uses 65 mm film, but photographs and projects it at 60 frames per second – 2.5 times the standard speed of movie film. It renders a picture that is not only extremely high in definition, but is dramatically smoother and more realistic in its rendering of motion, similar to that seen in video.
Trumbull had first come to the public's attention for his work on the ground-breaking special effects in movies such as 2001: A Space Odyssey, The Andromeda Strain, and Close Encounters of the Third Kind. He also directed 1972's Silent Running, widely considered a classic of 1970s film science fiction.
The Showscan Film process was developed in the late '70s and early
'80s by Trumbull, when he became interested in increasing the fidelity
or definition of movies. Similar to the quality issues addressed later
by high-definition television, the then-state of the art of movies suffered from the limitations of the medium. When projected onto a large screen, the film grain of 35 mm film stock
is often quite visible, which reduces the quality of the displayed
image, a problem further exacerbated by the larger grain used in the
fast film stock often used to capture high-speed action. Trumbull chose a
65 mm film stock for his new process to address this, providing a
higher resolution image.