Everything we see, we see twice. Everything is two images. Left eye, right eye. Our brains turn these two coincidental images into a single three dimensional image. Cover one eye and the world shifts.
The world around us is three dimensional. The world in film is two dimensional. So why should we want our two dimensional to be three dimensional?
When a 3D object leaps from the screen, your eyes turn slightly inwards to converge on it, but your lens stays focused on the light from the screen. This conflict can cause nausea. 1
Mars landers are fitted with stereoscopic cameras and therefore the images they send back can be used to make red/blue anaglyph 3D images. The phenomenal and the naff collide.
Concurrent. Synchronous. Coincident. Simultaneous. Blink.
“Two identical, adjacent, battery-operated clocks were initially set to the same time, but, with time, they will inevitably fall out of sync.” (see fig. 1)
A stereoscopic photograph of the sky taken on a clear day from planet earth. A three dimensional photograph of a blank surface that goes on forever. (see fig. 2)
Two stereoscopic photographs taken from an aeroplane flying at approximately thirty six thousand feet. One looking up and one looking down. (see fig. 3)
Everything is two images.