The 3D craze in all forms of entertainment has spread to the extent that the swag bags for journalists at Toronto’s G8/G20 summit include an iPhone cover designed to let you view 3D media. 3D is all the rage for movies and games, as consumers flock to something novel and seemingly high-tech and entertainment companies sense an excuse to boost ticket prices and (for now) offer something that pirated media does not.
I have one big problem with all of this: while it is easy enough to exploit binocular vision to produce the illusion of three dimensions on a flat screen, doing so doesn’t really take into account how people see. The effect works because of how our brain interprets parallax – the situation in which the perspective on a scene differs slightly when the viewpoint used changes. This is a problem for many point-and-shoot cameras, with viewfinders offset from the lens; you can compose a photo nicely as viewed through the former, only to discover that it doesn’t look so great when viewed through the latter. It also applies to the different perspectives offered by your two eyes. Your brain uses the differences between the two views as one source of information about how far away things are, feeding into our overall awareness about the three-dimensionality of the world.
Parallax is one important way in which our brains make sense of a three-dimensional world. Others include geometric cues, like how parallel lines seem to converge as they approach the horizon. Exploiting these sorts of cues allows artists to make works that seem to have depth. It is also one way in which optical illusions can be created. It is one reason why the very cool hollow face illusion works. Indeed, that particular illusion only works when seen without the benefit of binocular vision, which allows our brains to figure out that we are in danger of being tricked by geometry.
The trouble with 3D is what happens when our eyes go beyond perceiving a scene and into responding to it: specifically, by refocusing. When we see a rhino charging at us, the muscles around our eyes change the shape of our lenses so as to keep the beast in focus. Our eyes also turn inward, toward our noses. Unfortunately, when we are just looking at a false 3D image of a rhino, the re-focusing is not necessary. After all, we are still really looking at the same flat screen. This may explain why watching 3D movies is nauseating for some people; more worrisomely, it could cause people to learn to see in unnatural ways, in a manner that extends beyond the movie theatre experience.
This is not a problem that can be overcome, so long as our chosen mode of producing faux-three-dimensional images relies upon information displayed on flat panels. How important it ultimately will be, I can’t really comment on. Still, it is worth knowing that the exciting 3D experience consumers are being promised is premised on a limited understanding of how people really see moving images.
I loathe the new 3D trend. I watched Avatar in 3D and vowed then to never see another movie in that format. I had nausea and a headache for the first 20 minutes of the film (the headache persisted even after I’d left the theater), plus I had to spend the entire film holding the glasses up because they don’t fit properly on my face.
Roger Ebert pretty much sums up everything there is to hate about 3-D http://www.newsweek.com/2010/04/30/why-i-hate-3-d-and-you-should-too.html
Milan said: “Indeed, [the hollow face illusion] only works when seen without the benefit of binocular vision, which allows our brains to figure out that we are in danger of being tricked by geometry.”
Not entirely. Disney’s Haunted Mansion ride takes advantage of this illusion to make the face on a bust appear to follow the rider. The rider is far enough away that binocular disparity is minimized, but the illusion is still quite striking.
As for 3D, I haven’t seen any of the new 3D stuff and don’t have too much of an urge to. I don’t think that it is inherently bad but, as with the advent of CGI and increase in chroma keying, directors will come to depend on it at the expense of the plot.
I’ve experimented with 3D still photography of the red/ blue variety. You take one shot, move the camera over an eye’s width, and then take another. Then, in a graphics suite, you make one red and one blue and combine them.
It doesn’t make for ‘pretty’ photographs, but it is still quite satisfying to do. In my opinion, with a still image, it’s quite a different experience than with a movie.
Sega, one of the earlier pioneers with a stereoscopic 3D glasses addon to their Sega Master System in the late 80’s tried to develop a VR Headset for their next console, the Genesis, in 93-94 called Sega VR.
http://en.wikipedia.org/wiki/Sega_VR
At the time it was announced it was officially canned because execs were worried people would walk into traffic with the headset on, but rumour has it was really canned because testers complained it caused nausea, headaches, etc…
Which leads to another story I recently read cautioning about the long term effects of stereoscopic exposure.
http://www.abc.net.au/unleashed/stories/s2813511.htm
The guy is a 3D researcher and did work on the Sega VR system and mentions something call Binocular dysphoria.
http://en.wikipedia.org/wiki/Binocular_dysphoria
While I’d like to see some more peer-reviewed safety studies done, especially on long term effects before I say its dangerous., I think in the context of the occasional 2 or 3 hour movie I don’t think we risk permanent damage, however 2 to 3 hour daily exposure with 3D TV and video games is another matter entirely.
“Turns out 3D television can be inherently dangerous to developing children, and perhaps to adults as well. There’s a malaise in children that can prevent full stereopsis (depth perception) from developing, called strabismus or lazy-eye. It is an abnormal alignment of the eyes in which the eyes do not focus on the same object — kind of like when you watch a 3D movie. As a result, depth perception is compromised. Acting on a hunch, the guys over at Audioholics contacted Mark Pesce, who worked with Sega on its VR Headset over 15 years ago — you know, the headset that never made it to market. As it turns out, back then Sega uncovered serious health risks involved with children consuming 3D and quickly buried the reports, and the project. Unfortunately, the same dangers exist in today’s 3D, and the electronics, movie, and gaming industries seem to be ignoring the issue. If fully realized, 3D just might affect the vision of millions of children and, according to the latest research, many adults, across the country.”
Why Bad 3D, Not 3D Glasses, Gives You Headaches
“The most common complaint about 3D is that the glasses give you a headache, but that’s not actually true, according to the man who teaches the pros how to make better 3D. Speaking at the BBC in London, Buzz Hays, chief instructor for the Sony 3D Technology Center in Culver City, California, explained: ‘It’s not the technology’s fault, it’s really the content that can cause these problems. It’s easy to make 3D but it’s hard to make it good — and by “good” I mean taking care to make sure that this isn’t going to cause eyestrain.’ He went on to detail some of the mistakes made by inexperienced 3D film makers, from poor composition of shots, through uncomfortable convergence settings, to overuse of on-set monitors without viewing their content on a big screen. But the biggest admission Buzz made was that not even the ‘experts’ know all the tricks yet, which is why 3D should only get better from here. In the same seminar, Buzz also explained why 3D glasses are here to stay — at least for the next few years.”
3D Hurts Your Eyes
“After experimenting on 24 adults, a research team at the University of California, Berkeley has determined that viewing content on a stereo 3D display hurts your eyes and your brain. This can supposedly cause visual discomfort, fatigue, and headaches According to the article, 3D content viewed over a short distance (like with desktops and smartphones) is more visually uncomfortable when the stereo content is placed in front of the screen. In a movie theater, it’s the opposite: Stereo content that is placed behind the screen causes more discomfort than scenes that jump out at you. With the explosion of 3D-capable gadgetry such as televisions and mobile phones, understanding just what this kind of technology is doing to our bodies may help us better use it in the future. The only problem is that technology tends to far outpace research, and until we get a better handle on its effects, we’re more or less walking blindly into a 3D world.”
French Health Watchdog: 3D Viewing May Damage Eyesight In Children
A French health watchdog has recommended that children under the age of six should not be allowed access to 3D content. The Agency for Food, Environmental and Occupational Health and Safety (Anses) added that access for those up to the age of 13 should be ‘moderate’. It follows research into the possible impact of 3D imaging on still-developing eyes. Few countries currently have guidelines about 3D usage. According to Anses, the process of assimilating a three-dimensional effect requires the eyes to look at images in two different places at the same time before the brain translates it as one image. ‘In children, and particularly before the age of six, the health effects of this vergence-accommodation conflict could be much more severe given the active development of the visual system at this time,’ it said in a statement.