Build Your Own: Wall-Sized 3D Gaming, Just Like Theaters Do It

[mdrejhon]

I should do this sometime.

I was on the 3D home theater bandwagon 10 years ago, in year 2000 with an NEC XG135 CRT projector on a 92" screen, and an Asus V7700 Deluxe 3D kit (designed for 3D on CRT monitors, but worked perfectly on a CRT projector). This is 60 Hz shutter glasses 3D, with 30fps per eye. I loved playing Star Wars Episode 1 Racer in full 3D on a wall sized screen 10 years ago!

 

[mdrejhon]

Oh, here's the Toms Hardware article 10 years ago about the Asus V7700 3D glasses
http://www.tomshardware.com/reviews/video-excursion-asus-v7700-deluxe,223.html

 

[cleeve]

[citation][nom]post-it[/nom]unfotunately you need to do a bit more resaerch on theatrical display systems to provide correct info[/citation]

Not really.

As I mention on page 2, "Please keep in mind that we'll focus on the core points for the sake of simplicity."

I don't see much value in adding more layers of complexity to an already confusing subject, so I watered things down. If you have extensive knowledge of dual-projection and polarized systems already, then this article wasn't targeted at you in the first place.

 

[Guest]

This article got me thinking.
I read once a while back about a guy who built a large projector display by using an overhead projector like the ones used in classrooms, and then dismantling a LCD monitor and using the screen on the overhead to get a high resolution large projected image.
Since you can pick up 2500+ lumen overhead projectors for a couple hundred bucks, and used LCD screens for very cheap I am curious if two of them could pull off a 3D image for much less money that costly projector units.
I am tempted to try it myself but such a set up would be quite large and I live in a very small home.

 

[micksh]

Here are more applications for this setup. Stereo Movie Player and Stereo Movie Player
http://stereo.jpn.org/eng/stvply/index.html
http://stereo.jpn.org/eng/stvmkr/

They claims to work with iZ3D monitor and dual projector setup.
Can display side-by-side and interlaced 3D file formats. Some movies can be found in this format on the internet.
Stereo Movie Player can play Fuji FinePix Real3D W1 camera files.
It is also possible to convert anaglyph movies to real 3D avi.

 

[Humans think]

[citation][nom]Cleeve[/nom]unfortunately, no. Dual-projector systems are the redheaded stepchild of 3D displays and nobody in the industry wants to talk about them. The only feedback I got was how horrible the crosstalk is and how much better 120 Hz AFS displays are.We'll see if that's true in the follow-up... I'm still hearing a lot of comments about 120 Hz glasses causing headaches and being hard to watch for long periods. We'll see...[/citation]

From a medical perspective 2 things can be said:
1) The strain to the eyes and brain should resemble a CRT running at 60Hz which to my personal experience is horrible
2) Additional strain should also be in effect due to the glasses forcing the eyes to desynchronize image sampling from each other so from a physiological standpoint it should be logical to produce extra strain

The only thing that can be done to improve the technology is achieving RR of 200Hz for example

The only way to hit the industry trend is by reviewing the effect of the system on the brain, I searched for medical publications on the field but I found nada... Unfortunately ophthalmology and neurology are not my field so I can not be of any help :S

 

[codealdente]

Re: medical perspective

1) I also find a 60Hz CRT unpleasant. I also don't like working under fluorescent lights. Different people have different flicker sensitivity, so for many people this isn't a problem. As I recall, 80-90 Hz is the about the maximum sensitivity reported for primates. Flicker is more perceptible in the visual periphery, and would thus be a greater concern for setups with a wider field of view.

2) Desynchronized sampling would compound the problem if you can see 60Hz flicker, and you could probably add some sort of aliasing to the list of issues. If you can't see at 60Hz, then your limitation is almost certainly happening before binocular information is combined in the visual pathway (i.e., the retina, and probably its photoreceptors IMO), and the sampling shouldn't be an issue.

Of course, all this assumes that a 120Hz refresh rate is the true refresh rate of the system. I'm no expert here in this regard, but if, for example, the time course of the transition from a bright pixel to a dark pixel happened to be different than the transition from dark to bright, then more artifacts could arise.

 

[codealdente]

Cheers for this excellent article! I'm thinking of building one of these, but I'd like to do it at 1080 resolution, and have it work well for both movies and games. Looking at projectorcentral.com, I see a few 1080 models with brightness in the range 1700-2000 lumens (BenQ W1000, Optima HD20, Epson PL Home Cinema 8100, etc). Does anybody have a feel for how games perform at this brightness? How much more visible is the lower-res, brighter option used here?

 

[stephen0983]

The e7200 and GPUs make what would've been the most interesting read of the year a little less than. Really, who's going to spend 2700$ and go cheap on a CPU and GPU?

 

[Guest]

This article has a factual problem - RealD uses alternative frame switching and not dual projectors. They fit a polarization modulator over the projector so that you don't need shutter glasses, but only polarized glasses. The project itself run at a very high framerate (144 fps) show each frame 6 times, 3 times for one eye and 3 times for the other eye alternatively and they normally use silver screens to compensate for the loss of light to each eye.

 

[cleeve]

[citation][nom]annoyedjohan[/nom]This article has a factual problem - RealD uses alternative frame switching and not dual projectors. They fit a polarization modulator over the projector so that you don't need shutter glasses, but only polarized glasses. The project itself run at a very high framerate (144 fps) show each frame 6 times, 3 times for one eye and 3 times for the other eye alternatively and they normally use silver screens to compensate for the loss of light to each eye.[/citation]

As mentioned in the article, I have kept some aspects simple in order to keep the detals from overwhelming the point. However, I will say that silver screen's primary function is to keep the polarization of the light intact, not to compensate for the brightness. The polarization is lost on a normal screen.

 

[hixbot]

I'm curious about frame per second values when dealing with stereoscopic benchmarks.

For example, L4D with tridef driver gets 54fps, is that per eye (or per projector if you'd rather), or the combined total? Is game rendering 108fps total, half of which are meant for one eye (projector), and the other half for the other eye? Or is it rendering 54fps total, and each eye is receiving only 27fps? yes i realize this is then delivered at a higher refresh to avoid flicker, but i'm just not sure about what the renderer is delivering, (motion resolution).

For instance, in order to see 60 unique frames per second in each eye, the game must render at a total 120 frames per second. What i'm not sure about, is whether the benchmarks show total frames per second or for just each eye.
The difference is of course, huge! You'd need 60fps to be playable if it's a total number, but 30 fps is ok, if its per eye.

and what if one game measures it per eye, but the another, total?!

you say 20fps is playable for burnout, so i'm guessing that game is giving fps per eye.

 

[cleeve]

[citation][nom]hixbot[/nom]I'm curious about frame per second values when dealing with stereoscopic benchmarks.For example, L4D with tridef driver gets 54fps, is that per eye (or per projector if you'd rather), or the combined total?[/citation]

The value is for both eyes, the same as if the game were run in regular 2D mode.

 

[Guest]

Technology is still far away from perfect. The fps and resolution are still way too low for this kind of cash down. And the hassle of dealing with two type of games with games that not fully support the display seems like a headache by itself. I'll look into this when it becomes mainstream... but the idea of putting on glasses just to watch a movie sounds ridiculous to me... i'm tempted to wait for Holographic displays ;p!

 

[hixbot]

thanks for the clarification cleeve.

 

[Guest]

isn't that 60 pics per eye due to 2 pics per frame i.e. 1 left eye 1 right eye as opposed to 120 actual frames per second

 

[digitalprospecter]

Cool, but expensive!

 

[cleeve]

[citation][nom]river-runner[/nom]isn't that 60 pics per eye due to 2 pics per frame i.e. 1 left eye 1 right eye as opposed to 120 actual frames per second[/citation]

If the benchmark says 60 fps, then each eye experiences 60 fps.

That's not 120 fps, there's no value doubling that. The point of the benchmark is to demonstrate how smooth the experience is for the viewer, and so the result should be comparable to the standard we're used to.

 

[dlapham]

As pointed out, most theaters do not use dual projectors. They use either color wheels (Dolby 3D) or A push-pull electro-optical liquid crystal modulator placed over the projector called a ZScreen (RealD). All using alternating left eye, right eye frames (just like shutter glasses) on a single projector.

IMAX 3D still uses dual projectors and polorizers as mentioned here.

Some theaters use XpanD 3D which uses expensive shutter glasses.

 

[cleeve]

[citation][nom]dlapham[/nom]As pointed out, most theaters do not use dual projectors.[/citation]

I know! As I responded a few posts above, I left out some of those details for the sake of simplicity. I'm dumbing down the technical aspects a little because most of the audience is goming in from ground zero and I don't want to confuse them.

Having said that, I've gotten enough comments about this that I've amended the article to make this clearer. Hopefully that clears things up.

 

[Guest]

I don't want a 3D system I think cross viewing is the next rage. Never heard of it before but pretty cool hope my eyes don't get stuck.

 

[Guest]

I think there should be a follow up review comparing the polorized setup to the projector's built in shutter glasses setup. Not having a HQFS dvd is not an excuses since iz3d provides support for pageflip in games and you can download many sample videos from 3dtv.at and play them as pageflip with their player. While they are at it they should buy one more w600 and try out Nvidia's Surround Vision using all three projectors in 3d. Optoma's HD66 is another competing projector with all these same capabilities.

 

[tosvus]

I'm confused. In Wikipedia, RealD states ONE projector is used. This article appears to say that two projectors are needed. If it is true they can manage with one in the cinema (and spectacular results), what is the problem in doing similarely at home? It seems ideal to have 1 projector and $1 glasses.....

 

[cleeve]

[citation][nom]tosvus[/nom]I'm confused. In Wikipedia, RealD states ONE projector is used. This article appears to say that two projectors are needed. If it is true they can manage with one in the cinema (and spectacular results), what is the problem in doing similarely at home? It seems ideal to have 1 projector and $1 glasses.....[/citation]

As the page says:
"IMAX 3D, RealD, and Dolby 3D all use a variation of this 3D display technology (there are some technical differences but for the sake of simplicity we won't go into those details here)."

The RealD and Dolby solution does not have a home equivalent, unfortunately. The only way to do 3D with a single projector in the home is with the Nvidia solution AFAIK.

 

[Guest]

BTW - not entirely true that our ability to see 3D is based on requiring both eyes... Even with one eye, we still have 3D vision ability (though definitely not as "rich"). This is due to our eye slightly moving back and forth to get a slightly different view of the scene, which our brain combines into a 3D image.

Certainly this is not as "rich" of a view if you have only one eye open as it would be if you had both, but you do technically still get some the 3D perception even with one eye, even if you're focusing on an item. Try it and see.

That said, you won't get this ability from a 3D TV or with 3D glasses, these DO require BOTH eyes...