A lot of us 20-somethings might remember reading dinosaur books that came with a pair of 3D reading glasses. The left lens was always red, and the right lens was always green. With this magical combination of opposite color spectrum lenses, we could view dinosaurs in glorious, jaw-dropping 3D. Of course, when you’re 5 years old, you don’t really think about how it actually works. You’re just relishing the awesomeness:
Eventually, you discovered that 3D glasses didn’t just turn pictures into 3D – they turned video into 3D, too. By the time Avatar came out and reinvigorated 3D for the silver screen, you were already a die-hard. The recent release of Gravity reminded you that Sandra Bullock is still relevant, and Alfonso Cuarón’s sweeping action-packed scenes that may or may not have defied the laws of physics were cool. You started believing that $30 for IMAX 3D was worth it…and all because of a pair of red and cyan glasses.
As it turns out, anaglyph technology has been around for about 150 years. No joke. The first anaglyph image viewable through a pair of opposite-colored lenses was created in 1852 by a gentleman named Willhelm Rollmann in Leipzig, Germany. 3D films came literally on the heels of his invention, and by 1903, a short called L’arrivee du train by the Lumiere Brothers terrified an audience somewhere in France because they really thought they were going to be run over by a train.
In the years that followed, more and more anaglyph movies were made. Then they became really popular in the 1970s. Then people got bored of them. Then James Cameron was like, “Hey…I’m going to made a 3D film version of Pocahontas.” And now we are in the second golden age of 3D films.
Which begs the question – how on earth did people make 3D films like the ones we’re watching now (minus all the CGI and ultra HD quality) 150 years ago? Answer: because red and cyan glasses existed over 150 years ago.
Basically, anaglyph technology is actually very simple. You know how when you look at, say, an apple, you can perceive its “3Dness”, but if you were to look at a photograph of the same apple, you wouldn’t? That’s because of 2 things:
1) The ability of our eyes to focus on specific objects in varying fields of depth, and
2) The fact that we aren’t Cyclopses.
In other words, having 2 eyes actually helps us perceive 3D. Don’t believe me? Go find an apple, stare at it, then shut one of your eyes. You’ll notice – almost immediately – a loss in your ability to perceive depth.
Cameras can also be adjusted to focus on specific objects, so the real reason red and cyan glasses work is because we have 2 eyes. An anaglyph image is basically a composite of two images 2.5 cm apart (the distance between our eyes) with the same focus. One of these images is shot in the red channel, and the other image is shot in the blue/green channel, because RBG. When these two images are alchemically welded together – you see this glorious piece of work:
Those dinosaur books were the same way – the dinosaurs didn’t make any sense without the glasses on. In fact, they were a painful eyesore, an eyeriot, if you will. But once the glasses went on, everything became glorious 3D. That’s because the glasses filter out colors and force each of our eyes to see one of the two color-channel images. At that point, the visual cortex of your brain goes, “Oh, that makes sense. I get that.” And, voila – 3D apples.
Why haven’t businesses gotten into the business of 3D video yet? Well, probably because not everyone owns 3D glasses. Only the cool kids do. Ideally, videos would be viewable in 3D without the glasses, but affordable monitors that do this have yet to be manufactured outside of the Nintendo 3DS. So it’s entirely possible that, one day, businesses will start making videos mostly in 3D. Now how cool would that be?