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Screen With 180 Degree Field of View
emj writes to tell us project jDome has started actively soliciting consumer feedback and, of course, donations. They are currently promising to deliver their "180 degree FOV monitor" this year for a pricepoint of around $200. The videos and talk have been circulating for the last couple of weeks or so, but they have added a video of the supposed tech in action. Buyer beware, but I would love to see a couple of reviewers get ahold of this and let us know what the story is.
How much more for the projector? won't come cheap no matter how you look at it.
You're not going to be able to see the whole screen without turning your head. Isn't the average human's field of view between 120-140 degrees?
I write sci-fi for metalheads
This looks interesting, but I'm not sure I'd bother buying it. Setting the FOV to 180 and using it on a normal monitor seems to give nearly the same amount of benefit without the absurd footprint. This device doesn't look like it does much for smoothing out wide angle aspects, which would be the only reason to purchase one in my opinion.
I just watched the video and it looks to me like all the have done is stretched the standard view to fill the 'dome'. This results in all objects that are at the edges of the dome to be stretched and way out of proportion. The "man at the right" is a prime example of this.
Undetectable Steganography? Yep, there's an app fo
It's a $200 white, round umbrella. Then you still have to buy your own projector? I don't see anything new, apart from a new use for an umbrella.
That looks like it would give me motion sickness for some reason. Maybe it's due to everything being stretched out of proportion and whenever you turn it's constantly shrinking and expanding. I don't know but that looked like a piece of crap to me.
You're nothing; like me.
...although it might be possible with a pixel shader, the hardware would really need to support other projection types than just standard 3-point (and with some hacking the transformation matrix, 2-point) perspective.
For a dome projection, you essentially need a linear fisheye projection out of the card, and the cards just don't do that.
You could do it in software, render a hemicube in the buffer, use a pixel shader to map the appropriate pixels onto the circle, done. Except that to get to 'done', you have to go through some very expensive (in terms of performance drop) steps.
It's impossible to get a 3D stereo setup with a non-planar display like this.
Polarized projectors and glasses works just fine on a curved surface. (Computation's a tad different, but so what?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Let me get this straight...this guy wants people to DONATE money to help him produce something he intends to sell to others for a profit? Start talking about shares in the company and we might have something to talk about, but I'm not going to donate money so this guy can build a "community" to help him start a for-profit business.
178 degrees viewing "angle" on LCD motitor means a totally different thing. It means the angle you can look at an LCD and still see the screen. Nothing to do with field of vision.
The perfect display for playing Duke Nukem Forever on my Phantom console!
Welcome to the Panopticon. Used to be a prison, now it's your home.
FPS games give me motion sickness already, but that's because the distorted areas of the game are projected onto a plane, and when I track something to the side or bottom of the screen I look directly at them. Having them off in my peripheral vision would seem to reduce that. Having the game create a sphere map instead of one plane of a cube map (which is what it's effectively doing when you expand the fov inside the game) would be even better, because it would eliminate the corner distortion.
That totally reminds me of This
1) rear projection onto a deeply curved screen? Getting even illumination at the edges, where the light is striking at an angle, is going to be quite a trick, due to Lambert's law.
2) How are they going to avoid the problem of washout and reduced contrast due to light from one side of the screen reaching the other side? This is always a problem with deeply curved screens. It's very noticeable in IMAX Dome (Omnimax) screens. The only system I've personally seen that avoided it was the original Cinerama screen, which was a very specially built screen made of hundreds of individual strips. And that only worked because the screen was huge and you were sitting very far from it.
Cinerama and IMAX screens are huge and far away. They're almost at optical infinity. The texture of the screen is invisible. There's very little binocular depth cues to tell you that you're looking at a flat screen, and if you move your head (as you always do unless it's in a clamp), that doesn't give you any parallax cues to speak of. This means that the screen itself is hard to see, and there are practically no binocular depth cues. That in turn means that there's nothing to contradict the numerous depth cues you get from any flat picture (light, shade, interposition, etc.--see any perceptual psychology text). The screen itself falls away, the non-binocular depth cues dominate, and you have a distinct feeling of being in 3D space.
But this is a small screen a short distance away from you. That means:
a) The texture of the screen may be visible unless they're using some rather special screen material.
b) Again, because it's a small screen a short distance away from you, there will be enough binocular disparity between your two eyes for you to form a stereo image: that will tell you that you're looking at flat image in a bowl, and in the battle between those cues and other cues, it's not clear which will win. The same thing will happen when you move your head. In fact, if you move your head a few inches, you will probably be far enough from the center, as a percentage of the radius, that the image will show geometrical distortions.
I am very, very, very skeptical that this system will produce a high-quality 3D-like image in the way the IMAX does, or Cinerama did.
"How to Do Nothing," kids activities, back in print!
http://hardware.slashdot.org/article.pl?sid=08/01/08/1257258&from=rss
//holding out for the 5760x1200 version
3 feet wide, 2880x900 resolution, and no projector necessary.
Of course, it might be a bit pricy, but them's the breaks for something nice.
Most 3D games won't let you set the FOV to 180 degrees, since it's impossible using flat (pinhole?) projection that most of them use. This choice of projection is also why things look so distorted at the edges of the screen with a high FOV, and is why objects that are near you appear larger than objects in front of you, even when they're the same distance away, among other visual quirks. In order to show such a wide angle (approaching 180 degrees or above), you'd need to use a projection that's not limited to showing objects on one side of a plane, such as fisheye projection. This isn't normally done because it's technically simpler to do 3D rendering when straight lines in the world correspond to straight lines on the screen (that's the simplified explaination).
See this page for a visual comparison.
Duct tape, XML, democracy: Not doing the job? Use more.
Welcome to jDome, the world's first charity for supporting gamers developing substandard implementations of a cool idea. I know I wouldn't throw free money at a guy just so he can continue developing what is essentially a curved white surface. He doesn't even acknowledge that the distortion caused by projecting a flat image onto a curved surface is a problem, as one of his forum users brought up: http://www.jdome.com/phpBB3/viewtopic.php?f=8&t=8
Of course, if this guy does pull it off by sheer balls, and perhaps sometime down the line starts actually selling a decent product, more power to him. I just hope a bunch of hopeful gadget addicts don't end up tossing their money down a drain.
Combine a superior implementation of this idea with Johnny Lee's Wii head tracker and you'll have an amazingly immersive experience.
I remember playing with something pretty identical to this at E3, several years ago, a while before Flight Simulator X came out.
As I recall, it was more like 120-140 degrees rather than pretending it was full 180. Then again, I'm not convinced the jDome is true 180 either - think about it, one point, relatively close, projecting on to a hemisphere, by definition, can't get to the outtermost edges.
The experience was certainly cool and definitely added an immersive element.
It wasn't quite as cool as it promised to be though for the following reasons:
Projector resolution generally sucks - even now, 1080p projectors cost several thousand dollars vs. about $400 for a basic 24 inch 1920x1200 LCD monitor. Most likely, you're going to be hobbled with 720p which is on the low end of most gaming systems these days. Now factor in that 1280 horizontal resolution has to project both the normal ~60 degree view AND the sides. You're now at maybe the equivalent of 800x600 for the area your cheaper 1920x1200 monitor is showing. Sure, you get the edges - but at a massive cost to the center's clarity.
Whilst edges are nice, down is often pretty pointless. It looks great if you're flying with the instrument panel turned off. The moment you turn it on, that whole bottom half of the screen is now filled with your control panel and your legs. You've gone to all of this trouble and you see... a big grey panel and a nice rendering of legs moving pedals. Most FPSs are relatively planar and so, most of the time, all you see is the ground running underneath you. Sure, it's nice when you're shooting around an industrial complex with people above and below... but most of the time you're just trading resolution for watching empty space above and very close ground below. You'll notice our eyes are horizontal, giving a much wider field of view than a vertical one.
You generally need your input devices resting on something. Unless you spend a fortune on custom controllers, odds are you're going to need a keyboard and mouse for most FPSs, a keyboard, throttle, yoke and mouse for menus for flight sims. The table you need to put all of that on ends up obscuring half of your downward view anyway. Plus it tends to really suck, trying to use most input devices while standing anyway.
It's a fun concept. Much like shutter glasses and TrackIR, it's one that can add a whole lot of wow factor, albeit at the expense of real practical use. On the flip side, for those with money to burn, a 1080p projector, a fast gaming rig, shutter glasses to make it 3D as well and TrackIR to make swaying your head from side to side have a difference... it could be the ultimate show off gimick. Hopefully it'll be easy to wash, when motion sickness makes people vomit, too.
Oh dear. I was thinking this was something really cool like a peice of hardware or software that remapped the image for projectong onto a curved surface. Nothing of the sort: it is just a dome screen. All he does is run Crysis with a custom field of view. There is no perspective correction, which mean that straight objects like trees and cranes are bowed on the screen. On top of that, his idea increases the viewable area, but not the pixel count. Indeed the pixel count would be less, unless you could afford a projector with the same resoultion as a decent LCD monitor.
You either need a fisheye lens to snap on to the projector, or some kind of computational remapping. One of the only games I know of that remap the image in this way is Fisheye Quake (http://strlen.com/gfxengine/fisheyequake/index.html), and it is much more computationally intensive than regular Quake. I'd imagine Fisheye Crysis would be a nightmare to get running at a decent framerate.
This product is limited to games only, and games that allow you to modify the fov at that (changing the fov doesn't make the image fisheyed). I'd quite happily pay for something similar that I could use every day for CAD/CAM work. I think if he could find/make a fisheye lens that snaps onto the front of a projector, and market it for a bit more, he'd be onto a winner.
Fisheye lenses are very expensive, so the only cheap solution would be projection off a hemispherical mirror (http://local.wasp.uwa.edu.au/~pbourke/projection/meshmapper/), but I can see a way of doing that by rear projection.
Anyway, I would be wary of buying something that the manufacturer admits is "simple wire-frame and scotch-taped numerus badly cut letter-sized papers". I can't really see how this has been patented, as there is plenty of prior art for rear projected domes out there.