And Why the Industry Misses the Point

And why the industry misses the point time and time again.

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I am going to take a somewhat unpopular stance: I really like stereoscopic 3D. I also expect to change your mind and get you excited about stereoscopic 3D too – unless of course a circumstance such as monovision interferes with your ability to see 3D at all. I expect to accomplish where the industry has failed simply because I will not ignore the benefits of 3D in my explanation.

Firstly – we see a crisp image when our brain is more clearly able to make out objects in a scene.

We typically have two major methods of increasing the crispness of an image: we either increase the resolution or we increase the contrast of the picture. As resolution increases we receive a finer grid of positional information to place and contain the objects in the scene. As contrast increases we receive a wider difference between the brightest points and the darkest points from a scene which prevents objects from blending together in a mess of grey.

We are also able to experience depth information by comparing the parallax effect across both of our eyes. We are able to encapsulate each object into a 3D volume and position each capsule a more defined distance apart. Encapsulated objects appear crisper because we can more clearly see them as sharply defined independent objects.

Be careful with this stereoscopic 3D image. To see the 3D effect you must slowly cross your eyes until the two images align in the center. This should only be attempted by adults with fully developed eyes and without prior medical conditions. Also, sit a comfortable distance away so you do not need to cross your eyes too far inward and rest your eyes until they no longer feel strained. In short – do not pull an eye muscle or something. Use common sense. Also move your mouse cursor far away from the image as it will break your focusing lock and click on the image to make it full sized.

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Again, be careful when crossing your eyes to see stereoscopic 3D and relax them when you are done.

The above image is a scene from Unreal Tournament 3 laid out in a cross-eyed 3D format. If you are safely able to experience the 3D image then I would like you to pay careful attention to how crisp the 3D image appeared. Compare this level of crispness to either the left or right eye image by itself.

Which has the crisper picture quality?

That is basically why 3D is awesome: it makes your picture quality appear substantially better by giving your brain more information about the object. This effect can also play with how the brain perceives the world you present it: similar to how HDR tonal mapping plays with exposure ranges we cannot see and infrared photography plays with colors we cannot see to modify the photograph – which we can see – for surreal effects.

Let us completely ignore the difficulty of capturing a 3D image and pretend that we have a completely flawless method of getting from the camera or animation program to your display. Getting the information from the display to your eye is terribly difficult and almost always involves reducing your picture quality in order to make it happen.

Many televisions with passive glasses polarize every second line an alternating pattern of clockwise and counterclockwise circular polarizations. The passive glasses contain filters which block the incorrect polarization and allow the correct one through. If you were to wear these glasses and close one eye you would notice that every second line appears dark in what almost looks like a corduroy pattern.

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Why waste good work? Here's another UT3 3D pic.

So to get extra crispness you reduce your resolution crispness by a factor of 2. Sound counter-productive?

How about active shutter glasses? Well each pixel sends out an alternating image for each eye which the glasses correspondingly block in time. The problem is that you are losing at least half of the contrast which the TV is capable of providing and that assumes the manufacturer is able to prevent the wrong eye from “cross-talking” and leaking through the unintended lens.

What about passive holographic displays like on the Nintendo 3DS or upcoming glasses-free TVs? How these TVs work is they designate a pixel to belong to a specific eye and they use a lenticular effect to basically aim the pixel in the proper eye. You once again lose resolution on the display and get a holographic shimmery distortion over everything to boot.

Heck – just thinking about this is enough to make me go cross-eyed.

So we have not really found too many ways to get full quality 3D into your eyes without defeating the whole purpose in the process. Eventually we should find a way: whether it is the Oculus Rift, some form of laser display, or a lens made of distilled unicorn tears? Who knows?

Maybe we can trick the brain into believing in 3D some other way? Your brain can also acquire depth information by paying attention to the slight bobbling of your head. Some research has been done to track your head motions and adjust virtual objects in the scene correspondingly which your brain could use to build depth information. There was an old video demonstration of this effect using Wii remote hackery where it was even possible to make targets appear as if they were coming out of the screen and at the viewer despite being a completely 2D display. Maybe we need to completely rethink the problem in order to comfortably use 3D to increase image crispness? Maybe what we have just needs to get better?

There is a purpose for stereoscopic 3D. It just does not get considered very often…

Especially not by those who promote it.

As an aside: Remember how you can create surreal effects with 3D? Another problem with 3D is that some people get an equivalent of motion sickness. If you have not picked up on it by now: the human brain processes everything you do at all times. The brain is way more complicated than we give it credit for.

If you give your brain nonsensical 3D it will attempt to make sense of it in any way it can. One possible conclusion that your brain can reach is that the imagery is not the problem but instead that you are under the influence of a neurotoxin and cannot properly process the image. Of course you are not poisoned but your subconscious can think of no other solution. As such your brain will kick into survival mode and make you nauseous to eject the contents of your stomach.

This is just one example of how playing games with how your brain perceives the world can be difficult and require extreme care.