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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.
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.
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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.
...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?
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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.
$369 for a great 800x600 projector from Fry's.
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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.
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I don't know how much experience you have with projectors and gaming, but apparently it's not enough. I have a 3 year old BenQ projector that does 1080i or 720p HD at 1700 lumens. I have it on my wall at about 80" right now.
I have absolutely no artifacting, coloring, or whatever issues with the projector playing GTA IV on my PS3 connected to it. Sure, it's analog input so I'm not getting the best experience, but there are projectors from BenQ today for less money than I spent 3 years ago, that would do 1080p at digital input.
Anyway... just saying you're wrong that projectors aren't good for gaming. That was true 10 years ago with those old big-screen rear projection TVs... but those days are LONG gone.
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.
You can find your own FOV:
1. Draw two dots on a white board and measure the distance between them
2. Stand in the middle of these two points, but far away from the board
3. Start moving closer until the two dots disappear from your vision (of course, keep looking in the middle)
4. Measure your distance to the board when the dots have disappeared
5. Use middle-school math to figure out the angle
I found mine to be roughly 120 degrees
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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 ever achieve. If there is enough light in the room that the screen is clearly white with the projector off then you're pretty much guaranteed that the image will look washed out, even if the projector is bright enough to overpower the light in the room.
I seem to remember some "black screen" tech that Sony was showing off a few years ago, so maybe we will eventually get projectors that will work in daylight, but if you want to use a projector one of the trade-offs is that it will always look best in complete darkness... they're not built to be installed in your family room, they're best served in a purpose build room.
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