Please create an account to participate in the Slashdot moderation system


Forgot your password?
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. ×

Screen With 180 Degree Field of View 191

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.
This discussion has been archived. No new comments can be posted.

Screen With 180 Degree Field of View

Comments Filter:
  • by ZonkerWilliam ( 953437 ) * on Monday May 12, 2008 @04:21PM (#23383242) Journal
    How much more for the projector? won't come cheap no matter how you look at it.
    • Well, you can get projectors that do 800x600 for ~$500. Yeah, this idea seems made of fail. Projector =/= good gaming experience.
      • by twistedsymphony ( 956982 ) on Monday May 12, 2008 @04:55PM (#23383764) Homepage
        It depends on the game. I've been using a Projector as my main gaming screen for the last 7 years or so. My current setup is an Optoma HD-73 throwing on to a 94"x94" Dalite Glass Bead Pull-Down. I use an Xbox 360 for most of my gaming.

        some games become much easier to play, Fighting games, Racing Game, and Turn Based Role players. Other Games take some getting used to like FPSs and the Tony Hawk Series are nauseating at first due to the fast movement of the entire picture at once. Once you get used to it though, it's no different than playing on a normal screen.

        Some games do suffer though. For instance I do much worse when playing FPSs or DDR games on the projector because I have to move my eyes around the screen to see everything. On a normal screen 100% of the on screen activity is in my field of view 100% of the time. Also playing the Wii on the projector is difficult, for one you often find yourself casting shadows on the screen, and there are other issues associated with the IR pointer that make using that aspect of the controller difficult at best.

        Even still all Games are much more engaging and immersing on such a large screen IMO... I wouldn't trade my gaming setup for any alternative... Playing on a normal screen after the projector just seems cheesy by comparison.
        • That's interesting, but don't you have problems with the brightness in a well-lit room? Or do you game solely in the dark? Or have projectors gotten to the point in recent years where they can match the luminescence of a TV?
          • Re: (Score:3, Informative)

            Projector's aren't designed for well-lit rooms. My setup is in my basement and I have a more traditional well-lit "living room" on the main floor of my house where I watch TV on occasion and have the Wii hooked up.

            Newer Projectors do much much better in terms of displaying in a lit room... but they'll never reach the same visibility as a traditional screen.

            Think of it this way... The screen you're projecting on is white... The color of the screen when the projector is off is the darkest black you will
      • by KidKadaver ( 1099449 ) on Monday May 12, 2008 @06:03PM (#23384656)

        Projector =/= good gaming experience.

        Im not sure where this is coming from. I bought a mitsubishi 720p project for $800 over a year ago, and aside from a few key difference its pretty much equivalent to an lcd tv.
        The main hassel with a projector is that you need a sound system and you have to deal with light levels.Keep in mind that whatever your wall/screen looks like is what blacks are going to look like.
        I was worried about bulb burn out when I got my projector, but out of the projected 2000-3000 hour lamp life, ive only clocked ~650, so in my case ill likely replace the projector before the bulb.
        If you can take care of all that then its basically a 90+in lcd tv for a fraction of the cash.

        Some people mention resolution concerns, but for console gaming almost no games render at anything above 720p. Even games like gta4 that support 1080p just upscale.
        If 1080p movies or PC output are a requirement then theres always 1080p projectors, their still around $2k but that price has been dropping quickly. I assume if youre playing Crysis at 2560x1600 that price is no object.
    • by Toonol ( 1057698 )
      It needs to be viewed as just an neat, inexpensive accessory to an already-existing projector. It looks like a good device, but I doubt it will cause anybody to rush out and spend $1000 on a projector.
    • Re: (Score:3, Informative)

      by Maxo-Texas ( 864189 )
      $369 for a great 800x600 projector from Fry's.
    • by Venik ( 915777 ) on Monday May 12, 2008 @06:09PM (#23384746)
      I have a Mitsubishi HC4000U and a 120" screen. After trying a couple of rather expensive but unexpectedly lousy screens from a local home theater store, I made one myself using screen material I got on eBay. For about four hundred bucks in tools and materials it turned out better than a three-thousand-dollar screen from HTX.

      The setup works great with xbox 360 and PS3. Some people get dizzy playing Battlefield II or GTA 4, especially after a cigar or a couple of martinis :) The way to solve this problem is to lay off the booze and move a little farther away from the screen. From the very start you need to carefully choose the size of the screen that's appropriate for your projector and the size of your theater room.
    • I predict this will be bought up by a few gamers with disposable income, and then never heard of again. Alternatively, assuming the creator doesn't have any ethical problems with the idea, he'll add three zeros to the end of the price and sell it to the military for training simulators.

  • 180 degrees? (Score:5, Insightful)

    by Lilith's Heart-shape ( 1224784 ) on Monday May 12, 2008 @04:23PM (#23383280) Homepage
    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?
  • 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.
    • Erm... and how exactly could you set up a 180 degree FOV on a flat monitor? You'd need an infinitely-wide screen.
    • eg. [] ...not sure what graphics card I'd need though.

  • by arthurpaliden ( 939626 ) on Monday May 12, 2008 @04:26PM (#23383334)
    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.
    • by JCSoRocks ( 1142053 ) on Monday May 12, 2008 @04:32PM (#23383448)
      Yeah, the image quality doesn't look that amazing. I haven't looked at projectors recently, but last time I did, they couldn't put out the 1600x1200 that I currently play at. So you've got a lower resolution display, being stretched over a huge surface with distortion at the edges... It's an interesting idea but it doesn't look like a real improvement.

      If I were going to invest in tech like this I'd rather play on one of those wrap-around style displays that are basically just a semi-circular monitor... better image that way.
      • by Animaether ( 411575 ) on Monday May 12, 2008 @04:36PM (#23383512) Journal
        ...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.
        • Re: (Score:3, Insightful)

          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.

          Not really, this transformation can be done easily by lookup table where each pixel of distorted destination bitmap is mapped to one pixel in the source (undistorted) bitmap. Remember Second Reality Demo and bald guy? It worked smoothly on 486 (AFAIK).

          • I most certainly do - Future Crew was awesome :)

            However, just the "render a hemicube" bit is 'expensive' in its own right - this isn't a hemicube for some localized lighting effects that can be done in very low resolution - you need to do this in high enough a resolution that you don't get severe smearing at the peripheries. Don't get me wrong, if a game runs at 90fps (wtf) and with this it'll run at 40fps.. I, for one, won't care. But many gamers seem to... or they don't want to sacrifice particle effect
      • by im_thatoneguy ( 819432 ) on Monday May 12, 2008 @04:55PM (#23383770)
        Yeah the edge distortion is the problem. If they were really serious about delivering something of value they would also include a DX Scene shader to distort the image to compensate. The edges would be lower resolution but they would at least not look stretched.

        It would also require some really careful calibration by the user.

        All around.. product gets a big thumbs down from me as well.
        • by aliquis ( 678370 )
          They? It only seems like a single guy who has gotten this idea and talked about it with "Almi fÃretagspartner" which is a government own organisation which tries to help individuals realise their ideas and if possible start a new company in the end. And then Almi probably helped him a little with how to get the patents and prototypes and such. But for all I know he may not even be a coder at all, and he probably have no equipment for making the product either.

          If he started to build them on a bigger sca
    • Re: (Score:3, Insightful)

      by bugnuts ( 94678 )
      Aye, and due to the hemi-spherical display, the pixels will be stretched significantly at the edges.

      It'd still be good enough to give you plenty of peripheral vision, but you can't turn your head to focus on it ... you have to rotate your game character so that you get good resolution from the center.

      The pros are kind of cool - you can set your FOV in-game to 180 degrees (which normally gives a fish-eye look) and this projection will get rid of the fish-eye and put it back into normal viewing. This will gi
    • I suspect it has a better effect in person. The video camera only has a flat field of view, so it is transforming the curved surface into a flat representation. It may look more natural in person. That said, it doesn't look really revolutionary, just projecting onto a mini and inverted omnimax screen, and relying on the FOV setting in games to add the additional depth.
    • Re: (Score:2, Informative)

      by svnt ( 697929 )
      Yep. There are obviously simple lens options to get around this, but he doesn't make any mention of using one. All in all pretty boring. And donations? For something he's going to make a profit on? Where I'm from that's called an investment.

      These guys at CMU did some (I think) cooler work [] a while ago.
      • Re: (Score:2, Informative)

        by svnt ( 697929 )
        Jesus, I should have looked deeper. He just patented this []. And it's been discontinued.
  • a $200 umbrella? (Score:5, Informative)

    by smallshot ( 1202439 ) on Monday May 12, 2008 @04:27PM (#23383366)
    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.
  • I've always wanted an HMD... now that I've seen this, I think... I would still rather have an HMD.
  • It's impossible to get a 3D stereo setup with a non-planar display like this. One is better off spending their money on an autostereoscopic LCD monitor instead, which is more immersive.
    • Re: (Score:3, Informative)

      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?
      • by Prune ( 557140 )
        Then why do only flat IMAX screens support stereo 3D? IMAX Dome theatres can't display it. IMAX now uses digital projectors, so if it were as simple as you imply, they'd have implemented it.

        The fact is the problem is one of geometry, not technical issues of polarization. The parallax will only be correct for a very small sweet spot. The user of such a device would have to hold their head motionless, save for turning it.
        • by grumbel ( 592662 )
          When everything fails you could always just install a webcam, TrackIR or Wiimote and do some headtracking.
        • There are geometry problems: You get different results if you swivel your eyes and if you swivel your head.

          But flat screens have the same issue. Hasn't stopped using them for 3-D. B-)

          Since this is a single-user display you could use a head tracker to adjust the parallax depending on his head position, to avoid distortion, eyestrain, headaches, and barfogenisis. (This would not work for IMAX, because there are multiple viewers with distinct head positions.)

          Of course with only a hemisphere viewscreen you c
          • by Prune ( 557140 )
            In the end it's the wrong solution. Feeding directly into the eyes not only avoids these problems, but it's also the most efficient way to do it. It's pretty much the same situation with audio. For spatial accuracy, on the one hand you have Ambisonics with its spherical harmonics encoding, and the more speakers you use the better the spatial resolution gets, and unfortunately the smaller the sweet spot gets--plus you're chaining a bunch of speakers around a sphere. The flat screen analogy to audio then b
  • Correct me if I'm wrong, but wouldn't this require a specialized video card as well as software that's intended to make use of peripheral vision. If you don't have these things, it seems like they're just taking parts of the screen that would normally be inside your field of vision and moving it to the edges. The end result looks like you'd just have to turn your head to see what you'd normally be able to anyway.
  • Motion sickness? (Score:5, Interesting)

    by LilGuy ( 150110 ) on Monday May 12, 2008 @04:33PM (#23383474)
    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.
    • 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.
    • by aliquis ( 678370 )
      Tried playing at fov 145 on a regular monitor? Up to 115-120 or so in quake is ok but then it gets hard for me (thought I'm no pro.)
  • It seems pretty basic. You have a projector and a screen that resembles a halved sphere. Set the game to a wide FOV, project that onto the screen. The sides are distorted, but you get the kind of peripheral vision that you have in real life, except more distorted than normal, especially to the sides. Presumably you could compensate for that with software to some degree. Immersive gaming on the cheap is what this amounts to. It seems like a good idea in theory.

    Would this be worth it, though? What does it get
  • Donate?? (Score:3, Insightful)

    by Anonymous Coward on Monday May 12, 2008 @04:40PM (#23383566)
    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.
    • How about donating your time with quality assurance by testing and bug reporting or submitting patches to fix bugs or add features or writing documentation and howtos and faqs or helping other users in the community out reducing their support costs so the for-profit business can thrive.. oh wait; that describes Red Hat, Mysql AB, Whatever the company it is that is behind Ubuntu. etc. :) Giving money is just one step past that! 8^)
  • Excellent! (Score:3, Funny)

    by idontgno ( 624372 ) on Monday May 12, 2008 @04:50PM (#23383696) Journal
    The perfect display for playing Duke Nukem Forever on my Phantom console!
  • by dpbsmith ( 263124 ) on Monday May 12, 2008 @05:08PM (#23383928) Homepage
    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.
    • Re: (Score:3, Insightful)

      by hob42 ( 41735 )

      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.
      I don't think anyone sinking a whopping $200 into this should reasonably expect a high-quality experience comparable to IMAX.
  • by Alzheimers ( 467217 ) on Monday May 12, 2008 @05:11PM (#23383962) []

    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. //holding out for the 5760x1200 version
    • by karnal ( 22275 )
      LED and DLP = projector I'm guessing.... even if it's rear projection.

      And probably x4 of them, since the comments I see state that you can see the separation...
  • It's 2 sr FOV
  • ...misunderstandings arising from the way he pronounces the product name.

    There's a good chance that interest in his "Gaydome" may come from from somewhat different quarters than he had in mind.
  • This thing won't work. Increasing the FOV already causes terrible distorted images along the edges of your imagery. The very reason that I took back the Matrox Tripple Head2Go device a while back.

    Now you take this stretched image and project it onto a dome. The stretched images get further streched as it is smeared along the edges of the dome.

    Yes it is true that you don't see much detail in your periphery but you will be perfectly capable to interpret the direction of movement in your periphery vision. Beca
    • Now you take this stretched image and project it onto a dome. The stretched images get further streched as it is smeared along the edges of the dome.

      Right... the video card needs to provide exactly the opposite kind of stretch to pre-invert the distortion that the dome projection will cause. I play Q3 at 120 degrees FOV which gives me just a bit more 'around the corner' view than default, but not enough to really distort things. The downside is that the objects at the center of attention are proportionall

  • Now, we just need to expand that out to 360 degrees, and we'll finally have a linear cockpit!
  • donate? (Score:3, Interesting)

    by $random_var ( 919061 ) on Monday May 12, 2008 @05:42PM (#23384400)
    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: []

    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.
  • by nick_davison ( 217681 ) on Monday May 12, 2008 @06:16PM (#23384836)
    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.
    • 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 display is 180 degrees for the observer because the observer is not at the center of the sphere. The observer is between the sphere's center and the projection surface, the image can fill 180+ degrees of the observer's view without fully covering the entire near hemisphere.

  • ... it will only display the letter "I", sans serif.
  • 1) You'll get incredibly low resolution at the edges of the screen (think of the light rays gradually becoming tangents as they approach the edge of the "screen"). The very last six inches probably only has a couple of pixels covering it.

    2) You need stand in the middle of nowhere with two or three meters of empty space between the projector and the screen. How many people could fit that into their living space?

    3) Most of the screen is wasted. Humans have nearly 180 degrees horizontal FOV but only about 45 d
  • As many others have pointed out, this is a truly lame implementation of dome projection. He doesn't even try to transform the image properly for projection onto a sphere.

    It's not a bad idea; it's just done badly. It would make a nice arcade game if done well.

    You need to go into the game code to do this right, because you need a bigger field of view, and that affects the calculations of what's visible. This can create more work within the game. Not just rendering work, either; NPCs have to be active

  • shit right now.
    He needs some extra magic to add inverse-fisheye to the image coming out of the projector to make it appear correct to the user.
    • by anothy ( 83176 )
      see, this is why starting a sentence in the subject and continuing it in the body is a bad idea. i just used the toilet less than an hour ago and there's nothing left in my bowel. and why do i need you scheduling my bodily functions for me, anyway?
  • Scam.  Nothing to see here, move along.
  • by NimbleSquirrel ( 587564 ) on Monday May 12, 2008 @10:10PM (#23386916)
    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 (, 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 (, 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.

"The eleventh commandment was `Thou Shalt Compute' or `Thou Shalt Not Compute' -- I forget which." -- Epigrams in Programming, ACM SIGPLAN Sept. 1982