That intensity is heightened in 3-D; a process that involves filming images with two cameras simultaneously at a 90-degree angle using mirrors so that the viewer, wearing special glasses, sees a single three-dimensional image.

The proliferation of photographic and filmed images today has led to controversy, with some religious authorities stating, for example, that all television is un-Islamic; but this is not a widely held position.

They were my first professionally filmed images.

Filmed in 1957, the short film features inverted images of dancers (with choreography by Tudor) moving across a starry sky.

"They were my first professionally filmed images," he recalls in his book "Images," and he was terribly excited.

A similar effect occurs when filming projected images or movies off a projection screen.

Many historians give succinct lectures, which Mr. Grubin's team deftly illustrate with well-photographed works of art for the early periods, archival clips and cleverly filmed images of places and things.

Employing a technique of filming images in the space and then re-projecting those same images back into the space, the effect has been called "the blurring of our understanding of the physical and the mediated".

Eighteen American soldiers were killed, and a US television crew filmed graphic images of the body of one soldier being dragged through the streets by an angry mob.

Shahaf describes himself as "a scientist, a physicist specialized in ballistics and the technology of filming images."