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.

Ya $200 bucks and...

How much more for the projector? won't come cheap no matter how you look at it.

Re:Ya $200 bucks and...

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.

Re:Ya $200 bucks and...

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.

Re:Ya $200 bucks and...

ah, but look, my penis is longer still

tosser

Re:Ya $200 bucks and...

After playing an hour of Yoshi Touch&Go on _THE_ throne at the NDS 3" 256x192 LCD your big screen options seems rather crappy.

Projectors and 30" monitors may be great and all, but how do you get them into the toilet? ... I guess if I had a keyboard and mouse I could fold out from the wall, the machine built into the wall, screen ceiling mounted, oh wait, never mind, 30" is the shit!

Re:Ya $200 bucks and...

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.

180 degrees?

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?

Re:180 degrees?

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?

That's why you have a neck.

Re:180 degrees?

That's why you have a neck.

Hey! I'm John McCain, you insensitive clod!

Re:180 degrees?

Aw, shit, you mean you'd have to turn your head once in a while to see your surroundings? What the hell kind of realism is that?

rj

Re:180 degrees?

Peripheral vision doesn't really count though. While you're technically seeing that area, it's more of a dinosaur-esque movement detection than anything else. Have someone wave their hand around to the side of your head and you'll see it. Then try to count how many fingers they're holding up. Good luck.

Re:180 degrees?

I don't disagree. But its certainly more immersive to have something moving there than not.

Re:180 degrees?

That's why I have people waving their hands right at the edge of my FOV at all times.

Re:180 degrees?

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

Just flat projection on a doomed surface

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.

Re:Just flat projection on a doomed surface

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.

The flat projection is partially hardware...

...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:Just flat projection on a doomed surface

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.

Re:Just flat projection on a doomed surface

It can definitely be done well; NOAA/NASA's "Science on a Sphere" projector creates beautiful, seamless projections on a spherical screen (using 5 Linux boxes and and four projectors, but the project itself is closed source) http://www.nasa.gov/centers/goddard/visitor/exhibits/footprints.html [nasa.gov]

better video of the sphere in action:
http://learners.gsfc.nasa.gov/mediaviewer/sphere2/ [nasa.gov]

a $200 umbrella?

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.

Motion sickness?

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.

Maybe less motion sickness.

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.

Texture; parallax; uneven illumination; washout...

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:bad image, bad lighting

That totally reminds me of This [inktank.com]

The issue is the projection

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 [strlen.com]. 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 [strlen.com] for a visual comparison.