In computer graphics the graphics Turing test is a variant of the Turing test, the twist being that a human judge viewing and interacting with an artificially generated world should be unable to reliably distinguish it from reality.
[1] The original formulation of the test is: The "graphics Turing scale" of computer power is then defined as the computing power necessary to achieve success in the test.
Actual rendering tests with a Blue Gene supercomputer showed that current supercomputers are not up to the task scale yet.
[2] A restricted form of the graphic Turing test has been investigated, where test subjects look into a box, and try to tell whether the contents are real or virtual objects.
For the very simple case of scenes with a cardboard pyramid or a styrofoam sphere, subjects were not able to reliably tell reality and graphics apart.