Why 3D displays are bad for you & your kids

[qubit]

Ok, this doesn't quite fit into any category on TPU and it's not general nonsense, but 3D is the next big thing and it affects anyone who's thinking of going 3D with their PC or TV, so I've put it under Graphics Cards. Perhaps we could have a new 3D graphics section?

This article talks about the dangers of excessive exposure to 3D displays and the potentially damaging effects of binocular dysphoria. In particular, it could potentially lead to lasting brain damage in kids. The author hopes that 3D TV dies a quiet death because of this problem.

I really like my nVidia 3D Vision, but has this effect on me too (feels odd and slightly disorienting and occasionally very mild 'virtual' nausea) leading me to want to dip in and out of it as on occasional treat, rather than get stuck in it for hours on end.

Virtual reality headsets use the same technique for displaying 3D as we find in movies or 3D television sets - parallax. They project a slightly different image to each one of your eyes, and from that difference, your brain creates the illusion of depth. That sounds fine, until you realize just how complicated human depth perception really is. The Wikipedia entry on depth perception (an excellent read) lists ten different cues that your brain uses to figure out exactly how far away something is. Parallax is just one of them. Since the various movie and television display technologies only offer parallax-based depth cues, your brain basically has to ignore several other cues while you're immersed in the world of Avatar. This is why the 3D of films doesn't feel quite right. Basically, you're fighting with your own brain, which is getting a bit confused. It's got some cues to give it a sense of depth, but it's missing others. Eventually your brain just starts ignoring the other cues.

That's the problem. When the movie's over, and you take your glasses off, your brain is still ignoring all those depth perception cues. It'll come back to normal, eventually. Some people will snap right back. In others, it might take a few hours. This condition, known as 'binocular dysphoria', is the price you pay for cheating your brain into believing the illusion of 3D.

ABC

 

[ShRoOmAlIsTiC]

3D shit never worked for me, Im blind in one eye.

 

[human_error]

Interesting read, i definately used to get the disorientation after i stopped gaming in 3D or watching 3D films (at home or in the cinema). One thing i have noticed however - since i use my 3d monitor a lot more now i'm finding that the 3d effect feels more real more quickly (under a minute now for it to feel natural) and after watching 3d content i almost instantly lose any disorientation, which used to take 10-15 mins to go sometimes.

I think our brains will do what brains do best - learn and adapt. If the brain knows it is watching fake 3d (from lack of cues or from a concious understanding) it will very quickly ignore the lack of other cues. When it realises it is now in a true 3d environment with proper 3d scenery (again from the sudden appearence of the missing cues or again from the concious knowledge) it will work with the full environmental awareness again. I have definately noticed my brain is "switching" (for lack of a better word) between the 3d screen and the real world as the 3d feels more realistic, and feels more real more quickly (the 3d looks more 3d to me now in the same games/films) and it feels more real more quickly. Also when i stop watching a 3d monitor/tv/cinema screen i seem to almost instantly switch back to real world mode.

I remember when i started playing long gaming sessions (on 2d tv/monitors 10-15 years ago) my eyes would be killing me after 3-4 hours and i would get headaches. Over time my brain got used to it and now i can play 20 hour sessions and feel fine (other than needing a good shower and some excercise).

 

[qubit]

3D shit never worked for me, Im blind in one eye.

Hey, I'm sorry to hear that, buddy.

Interesting read...

It looks like you've adapted to it very well there. So the electronic 3D now feels more 3D than before? And I'll bet it feels more 3D than the real thing you see every day (I know it does for me). Interesting.

Are you using 3D Vision - because that has a depth adjustment to it. This changes the amount of parallax, either making it awesomely more 3D or making you more cross-eyed.

Personally, I don't think people will end up "brain damaged" by it, but they may well develop various problems, such as vertigo and coordination problems to overexposure to it.

When playing shooters like Unreal Tournament, I find that it's actually slightly easier to aim when playing in 2D than 3D. Seems counterintuitive, huh?

 

[Papahyooie]

The wikipedia entry specifically says that 3D movies use Stereopsis, not parallax... And from reading it, stereopsis describes what 3D movies use better.

 

[human_error]

It looks like you've adapted to it very well there. So the electronic 3D now feels more 3D than before? And I'll bet it feels more 3D than the real thing you see every day (I know it does for me). Interesting.

Are you using 3D Vision - because that has a depth adjustment to it. This changes the amount of parallax, either making it awesomely more 3D or making you more cross-eyed.

Personally, I don't think people will end up "brain damaged" by it, but they may well develop various problems, such as vertigo and coordination problems to overexposure to it.

When playing shooters like Unreal Tournament, I find that it's actually slightly easier to aim when playing in 2D than 3D. Seems counterintuitive, huh?

Yes the electronic 3d does feel more 3d than before, possibly as my brain is no longer looking for cues which are not present. The visual i see seems to have the depth it just feels more real to me and so is "more 3d" (it's just more convincing and so i can feel more immersed in the visuals).

As for feeling more 3d than real life i think it does, but it is what i refer to as the hd effect - hd films let you see more small details than in real life as they are scaled larger ( a close-up of someone's face on tv is far bigger than you would see someone's face as being), so you see details you would not normally see due to scaling. With 3d the depth and pop effects need to be overdone so you get the 3d effect - this is because you are seeing 3d on a smaller screen (the cinema is a bigger screen yes, but the scenes are heavily zoomed in so like hd you get the 3d effect being enhanced due to image scaling) than what you normally see 3d on, so the depth is condensed into a smaller area (or scaled up), giving it a greater 3d effect.

As for the 3d tech i use i'm using an ati 5970 so 3d vision was never an option, but i don't like shutter glasses personally (worked with 3d tech at uni and although it is good moving my head quickly can give a flicker effect) so i use a passive polarised screen and tridef 3d drivers. The passive screen works by polarising horizontal lines of pixels differently - my left eye sees pixels polarised clockwise, and my right sees counter-clockwise polarised pixels. The polarisation switches every line, so my left eye sees 540 pixels (hd screen) and my right sees the other 540 pixels - the effect is very good to be honest as when your brain combines the 2 eye's images into one image you get a hd image which works as well as active shutter in my experience. The bonus i get is no flicker and i can game at 30fps since both eyes see every frame, so framerate requirements are the same as 2d gaming. I used to have the 3d turned to half way on the depth slider but as i have got used to it i now have the 3d slider turned all the way up.

As for aiming in fps games i completely agree with you - the problem is when aiming in 2d or in real life your crosshair is practically in the same place for each eye and you tend to aim with one eye as well. With current 3d tech the crosshair is usually split apart for each eye to see -the problem is you aim with your primary eye (my right eye for me) but unless you close your left eye the image your left eye sees "moves" the crosshair to the left, so you miss. Plus the 3d effect is more pronounced in 3d screens to get the wow factor so it is harder to aim. I would hesitate to guess it is just a matter of getting game engines coded correctly for crosshair placement (avatar:the game seems to do it fine as it has a native 3d screen supporting engine) plus we also need to adjust to be able to aim again - when i played 2d games it took a while to get my eye in, and that was a simple place crosshair over these pixels - now we have to not only re-learn, but also put the crosshair over these pixels for the left eye, or those different pixels for the right eye (which will take a lot of adjusting).

One advantage i get with 3d gaming is depth perception and trajectory tracking - in avatar: the game i can easily dodge rockets fired at me instinctivley and see where i am being shot from as my eyes can track the trajectory better than in 2d. I can also fire weapons which suffer from droop over longer distances as i can see how far i want to fire better and so can judge the droop to compensate for better. Platform games and games which rely more heavily on situational awareness and depth perception over precise aiming should do better with 3d gaming (assasins creed, prince of persia, portal are good examples of games which don't need precise aiming but do well having good depth perception for jumping over gaps).

 

[$immond$]

Our professors would throw any essay that had a reference to Wikipedia. I am not sure if I can trust it so much.

 

[Benetanegia]

After reading the wikipedia article I'm trying to find the cues that 3D display lack and I only found one of any significance..

The two binocular cues, stereopsis and convergence, are there on stereoscopic 3D.

And most of monocular cues are on regular ("faked") 3D computer graphics like: motion parallax, depth from motion, perspective, relative/familiar size, aerial perspective, occlusion, texture gradient (maybe disabling anisotropic filtering is better for our brain?? ), and lighting/shading. All those are there in standard computer (3D) graphics, at least in the latest games and they certainly are on films. The only two that are not are accomodation and peripheral vision (yet). Accomodation is certainly what makes it difficult to adapt to 3D, but I don't think it's that important or that we could loose the ability to focus.

I don't see peripheral vision as a problem either, since you are still seeing what's outside the screen and your brain should be able to process and differentiate what's outside the screen and what is inside of it. I know I do, and we know it's a problem to get completely immersed in the game/movie. Does Eyefinity make it better or worse? With Eyefinity you are faking a lot of peripheral vision so does it make better or worse? I think it's worse according to the article, at least until we can use 24 screens to cover 180º horizontally and vertically...

All in all, I think the ABC article is exagerating and a lot. There's absolutely no permanent problem there IMO. You will still have to accomodate your eyes when you go from real 3D to computer 3D and viceversa, but that's all.

 

[newconroer]

How many people here are suffering diminished vision because of staring at computer screens for too many years?
How many people here are not suffering noticeable vision loss, but have a problem refocusing on objects after sitting at a computer for a while?
How many people here have used virtual reality headsets, or simply headsets with lenses that lay flush on your eyes to create the immersion illusion? And consequently felt like passing out afterwards?

Now how many of us actually think 3D television (when people already watch way too much television already), is NOT going to have similar effects and results to the symptoms mentioned above that are a result of staring at monitors all the time? Hell, just watching normal TV can mess up your eyes, a computer monitor is worse, and 3d will be the next step.

I don't know if this article from a medical/science approach, is entirely accurate or entirely comprehensive, but it's touching on truths that we already know : Screens mess with your eyes, 3d will only make it worse.

And God forbid if 3d televisions kick off any seizures in small children(who weren't prone to epilepsy to begin with), who were having a nice time enjoying Barney in all his purple glory.

Anyways, 3D television still has a ways to go, before it's mainstream - not only in a sense of availability(Samsung has a few models out now, and LG's should be here in a month or so. Sony's 60" is apparently available, but hard to get a hold of), yet also it's application and ease of use.
There's still lots of arguments over active versus passive - just the fact that you have to wear any type of glasses to sit down and watch television while you eat, conjures up some image of a ridiculously corny 1950s science fiction film, about a family watching television, when all of a sudden aliens knock down their door.

I don't see 3D becoming popular in the home environment, until the panels are truly 'passive' - meaning no glasses or accessories are necessary. This does exist, but it's early days still, and there's lots of issues.
Though as a summary, the image would crumple in on itself, meaning the depth perception seems to go INTO the image on screen, rather than coming out towards you with a pop-up book effect.

 

[Benetanegia]

How many people here are suffering diminished vision because of staring at computer screens for too many years?
How many people here are not suffering noticeable vision loss, but have a problem refocusing on objects after sitting at a computer for a while?
How many people here have used virtual reality headsets, or simply headsets with lenses that lay flush on your eyes to create the immersion illusion? And consequently felt like passing out afterwards?

I'm totally skeptic towards the relation* of screens and eye problems. I'm 27 and I've been in front of a computer several hours a day since I was 10. I have no problem on my eyes except that I have low myopia, 1.5/1.75 diopters. My parents were myopic too (3-4 diopters), and my grandparents, aunts and uncles too, it's hereditary (my parents didn't have a TV until they were age 20 and the first computer was the one they bought for me).

Except for the fact that I need lenses my sight is perfect, as described by my oculist in more than one occasion, way above the average, included those without myopia. The funny thing is that my myopia stopped growing at the same time that I started being in front of the PC for several hours a day. I relate it to pure coincidence, but related or not, I can definately say that in my case, being in front of a screen several hours a day has not hurt my eyes, in any case quite the opposite. In my family I'm the one with better vision, with the exception of my brother who... try guessing... started on PC the same day I started, but being 3 years younger. In his case being a young kid didn't make him more exposed, it rather looks like he was more protected than me.

I'm not saying it's cause/effect, but it has not hurt us, definately. My parents and many of my uncles who never had a PC or even a TV until late have far worse vision than we have (I mean, they always had, at same age as me). Apart from that I know many people who have no problem and spend several hours in front of the screen and I also know people who don't watch TV and have "never" touched a PC or console and they have some problem, for example one has chronic eyestrain. There's no relation between exposure to a screen and vision problem in the people that surround me and that's why I'm very very skeptic. Probably or maybe helps develop an already existent vision problem, but I highly doubt that a healthy eye can get in trouble from being exposed to a screen.

And BTW I've always used and still use a CRT monitor, the most evil display that someone could have (at least that's what they say).

* Just to make it clear. I'm not denying a relation, but I do think it's not as pronounced as they make it to be. Far from it. IMO there's many other factors of far grater importance, probably environmental or genetic. At least from what I can see from all the people that surrounds me there must be something and it is not exposition to a screen.