So it IS lenticular. Which I would have to see working (a video, not a still) to accept at this point. It certainly isn’t screening at anybody’s local cinema just yet.
I haven’t seen one displaying a video, no, and the imaging was rather crude. But seeing the scene appear to pop up out of the display left quite an impression on me.
Not to mention post #5
Apparently there were three different autostereoscopic (i.e., no glasses) 3DTV technologies at CES 2010.
Is this a woosh? I have two eyes but if I close one of them, making myself temporarily monocular, I can still perceive 3 dimensions just fine without moving my head.
You get a little bit of depth information from focus, but the majority of your depth perception is due to parallax.
Well, a big chunk is from context, too. If you see a person, for instance, you know about how big a person is, and you know from experience how far away they’d have to be to look that size. You could be fooled by seeing a giant at a greater distance, except that giants aren’t very common. There are also clues from things like the geometry of the surface you’re standing on, what obstructs what, etc.
That said, the non-parallax clues you get are all also present in a movie, even an ordinary “2-d” movie.
Or, put another way…
I don’t have stereo vision either. The concept of a “3-D” film just seems odd to me, because I’ve never looked at a normal film and thought “Yeah, okay, but it’s too flat.”
Parallax is present in regular 2-D films, of course, but only feels 3-D when your vantage point is moving. Parallax is the context that tells our learned vision (mono or stereo), what is closer or farther away.
But depth perception is only possible with stereoscopic vision. Each eye has a slightly different vantage than the other (thereby, giving each eye different parallax information), and it’s when these two sources are mixed in the brain that we feel depth-perception.
While parallax can have a dramatic effect when faking it on a 2-D medium, such as that cool youtube video in post #4 that BigT linked to, it requires you to constantly move your head, whereas stereoscopic vision doesn’t.
Think of it this way:
If evolution had given people only one eye, we’d have to be constantly bobbing our head back-and-forth to determine accurate depth.
However, given two eyes, separated apart slightly on the horizontal, this does the same job by taking two of the same images with slightly different parallax (essentially doing the same job of bobbing your head back-and-forth) and mixing them within our brain to create one coherent image, but with a profound and novel sense: depth.
The reason why stereoscopy is the winner when it comes to 3D viewing, is because most people already have two eyes, so the technology to create the illusion of depth is much, much simpler than to create the illusion of parallax (depth is arguably the cooler sensation, anyway). Now, what would be the ultimate? Depth + parallax.
Depth perception is anything that lets you determine the distance to what you’re looking at. Parallax, apparent size, and contextual clues are all elements of depth perception.
Parallax is depth perception based on the different views seen from different vantage points. This can be the different vantage points from your two eyes (stereoscopic vision), or different vantage points from moving your head.
All elements of depth perception except stereoscopic vision can be and are incorporated into normal 2D movies (in fact, it would take extra effort to not incorporate them). Even parallax can be introduced by moving the camera around. The only drawback to that is that it’s the director who chooses how the camera moves, not the audience.