Most 3D operates on a single basic principle – tricking our dumb, binocular brain into interpreting a 2D image into one with depth. The most basic way to do this is stereoscopy, which is essentially showing a slightly different image to each eye which the brain mashes together into a 3D image. We’ve broken up the million different ways to do 3D in a few broad categories.
It’s easiest to do stereoscopic images with glasses or other nerdtastic eyewear to change how you see stuff – hence there are a lot of variations in 3D glasses tech.
• An anaglyph image is the old school 3D we all know and got headaches from: An image has two different colour layers, one for each eye, with slightly different perspectives and when we look at them through those awesome plastic glasses (usually with red and blue lenses) that block one layer in each eye, our dumb brain takes the resulting separate image from each eye and mashes them together to make a 3D scene in our head.
• ChromaDepth is perhaps the fanciest glasses tech using micro-prisms and whatnot (hello red and blue again), but all it essentially does is slightly shift the way colours are perceived in each eye, so they see different things and boom, 3D. The major limitation of the tech is that if you change the colour of an object, you also change how its depth is perceived, since it’s all based on colour. (Check out the video above, done in ChromaDepth, to see what I mean.) [Thanks David!]
No Glasses Required
OK, so you don’t wanna wear glasses. No problem – you just move the one-image-per-eye dance to the display itself.
3D in 3D
So far, we’ve just talked about 2D images on a flat screen, which your brain is fooled into thinking are three-dimensional. The other side is creating images in real 3D – you know, meatspace. Still, most of them make use of lighting and projection tricks too.
• Heliodisplay actually creates a surface in mid-air to project an image onto, which allows you to do the “Help me Obi-wan Kenobi” type of floating holograms that look 3Dish, though they’re actually planar (2D) images. Yep, it’s expensive.
FAKE FAKE FAKE
There are lots of suggested 3D images out there that aren’t any kind of real 3D – video games are, of course, the most obvious. But why pick on them when you can pick on CNN?
• Sorry Wolf, but we gotta hit people with the truth: CNN’s “holograms” are totally fake. We already explained this before, but no one was projected in front of Wolf Blitzer. He was looking at a wall. What we saw at home as computer-generated: A bunch of HD cameras filmed the hologramee from all sides, computers crunched that data and delivered whatever angle the studio camera needed at the time. As long as the source angle was synced to the studio angle, it looked, to viewers at least, like a 3D “hologram”. Nice try, Wolfie. Call us when you score an R2 unit.
– With Reporting by Seung Lee. Post updated with two additional 3D technologies.