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Poor Man's Stereoscopic Projection
Jed Link writes: "This summer I helped built a Geowall
stereoscopic projection (3D) system for the
Southern California Earthquake Center. Although there are no new
concepts involved with this system, what is new is that the system cost a
little over $10K and is comprised of materials that you can buy at any
computer-hardware store. A complete description of the system, as well as
a diary of its assembly is available here. Traditional stereoscopic projection systems like
The Cave which is
used primarily for new product modeling and on a few university campuses cost
anywhere from $150K to $1.5M. They are built into a fixed location, often
requiring significant architectural modifications, so transportability isn't
even an option. The Geowall, on the other hand, can be fixed to a cart
(like we've done) and rolled from room to room. The price-tag makes the
system feasible for undergraduate post-secondary education classrooms and even
high schools. The system is based on a very simple concept, and while its use is currently
primarily educational, I think it's only a matter of time before we see
something like this in the gaming or entertainment industries."
Not exactly poor man then. More like upper middle class.
Oh well, back to looking at my 14" screen.
I hope somebody really cares. There isn't any room for discussion here.
I couldnt really get it. This system works on using 2 lenses instead of one... in case of gaming much would depend on the monitor.
However i see a use in military tech coz a two eyed robot can really see better than one.
Also in case of volcano exploring robots, currently robots have one camera so judgement of distance has to be done by radar etc which is expensive... and extra cost. Such a system will birng the cost down.
But going by past expirience i guess the military will be the first to lap it up.
My Aurora : http://www.youtube.com/watch?v=o91ZsGwJYyg
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Bear with me here. I'm a little slow. Are you saying you could use this thing to turn a small room into a virtual environment (like the holodeck) for gaming? A room like my living room? For 10K? Cool.
Can I bum a sig?
I think that perhaps traveling systems like these could do wonders to teach and inspire children (K-12) about mathematics.
Maybe even get them fired up about graphics and visualization research.
At least it can be a cheap way to setup and show 3d movies.
One small step for man, one huge leap for Muppets in 3D.
-- dK
It costs 10K now, but once the p0rn industry gets into the market, we'll all, errr.. I mean, you'll all be able to buy it for under $1K with economies of scale.
...then open up your Q3A console and type "/r_stereo 1" followed by "/vid_restart" ;)
(change the value of cg_stereoSeparation to suit your taste)
Gotta buy one. I can't be the last geek in Michigan without one.
I use real caves on a daily basis. Looks like I'll try building this one at home to see if it can compare to the ones at work.
The biggest issue I see is having a room long enough to put the projector(s) behind the screen far enough to make it large enough to have fun with.
Gator/Claria is Spyware.
why would secondary school education need something like this?
some please point this out to me
The author is completely off the mark in comparing his "geowall" ($12k, mobile, stock parts) to a cave system ($120k, fixed, custom parts). The projectors are easy for a cave, too. They cost a few thousand dollars, and use the same NVIDIA trick as he does. What is expensive and difficult is the motion/orientation-tracking system. The last cave I was in used a magnetic field to precisely detect the position and orientation of the viewer, thus moving the image ot make it seem like you were crawling around inside the scene. This has to be pretty precise, IIR, or else it feels wrong. And getting a good rectilinear magnetic field the size of a room takes lots of metal -- hundreds of pounds of shielding, permanent magnets, electromagnets, etc -- positioned very carefully all over the room. Not to mention the sensors. This is the part that costs $100k.
You may not be aware of this, but there have been 3D porn movies for some time. The Egyptian Theater in Seattle sometimes shows them for their midnight movies on the weekends. Pretty goddamn amusing stuff.
My deviantArt site
Its a cool idea but I thought that the since our eyes are in a horizontal direction the projectors should also be in a horizontal direction. Whereas this system is putting the projectors in vertical direction. I don't know how it will look with the vertical projector placing. The main price of this setting is anyway getting the two projectors.
You could easily knock off another 1000 USD by building the computer yourself. That's one of the more expensive (read server) dualie boards out there.
Plus it would be nice to be able to script the creation of the images to make movies. Can The GIMP be made to do this? So if you were able to avoid using Windows XP and Photoshop, my guess is that you could really come close to having a sub-10k setup today.
To-do List: Receive telemarketing call during a tornado warning. Check.
I read this Licentiate Thesis work sometime ago, and if you are interested in getting to know virtual reality/environment techniques and CAVE construction it is excellent. It's PDF and over 700K, 146 pages.
Well, the ones who really need it (car designers, whatever) probably care about the 'minor imperfections' and are willing to spend the additional 140K. As for the others... well... i think i'd rather spend 10k on regular CRT monitors + stereoscopic glasses (the ones making your left/right eye see even/odd frames). I am too lazy to look up the price tags on these, but my guess is i can get a whole monitor + glasses set well under 500$. So, 20 sets that can also be used as regular monitors instead of one projection set seems a good deal to me.
Why would the military be interested in a cheap cart-mounted projection system? Are they going to run out to the battlefield with one of these in tow? And what does a projection system have to do with stereoscopic aircraft vision? Answer: nothing. These applications are far better suited to head-mounted displays.
And for games, why would you think you'd get rid of your monitor? That's just dumb. You don't sit the thing on your desk; you mount it anywhere you want, to project onto your wall of choice. Plus, all your points regarding gaming totally contradict your very first sentence.
I could go on, but I have this terrible sinking feeling that I'm responding to the most finely-crafted troll I have ever seen.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
And here I was thinking there's an easy and cheap way to make stereoscopic videos!
After reading it I think I'm gonna stick to my Asus 7700 with the polarizing lense that came with it.
eTrade SUCKS
These things are quite commonly build out of one expensive projector and an SGI box. There are many of these and they are mostly used for viewing 3D models (of geological surveys, cars, proteins, ...) for a group of people. If you are alone, then you can easily use active stereo on a big CRT screen. ... Maybe that would be a good training for geeks wanting to work for the FBI!
I think it is interesting that these people have done a cheap version of a one-wall cave, but caves are most impressive when you have more than one wall! I've personnaly used caves of 3 (floor and corner) and four walls (floor and 3 vertical walls, i.e. a room without ceiling and one wall), and I know of people who have played Doom in them. They told me that it was physically tiring because you had to move, duck,
I'll do it for cheesy poofs.
This system doesn't use a monitor, and it has nothing to do with two-eyed robots.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Course: How To Build a Slashdottable Site
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Use the homebrewed projectors "Slashdot|Homebrewed LCD Projectors" instead of off-the-shelf and the price should become pretty reasonable ($1-$2K tops I would think).
I've seen a fair few 3D systems lying around - already, universities have 3D projection systems, and these are often used in CAD visualisations.
To be able to view 3D images without 3D glasses is crucial to the success of such a system, especially if it is to be marketed to consumers. There are all kinds of systems involving glasses, from the basic red/green system to (I don't know if this has been tried; if not, I was there first!) using two projectors with polarising filters, and glasses with polarised lenses, which preserves colour.
I remember seeing on Tomorrow's World several years ago a demonstration of a 3D TV, which required glasses to view. Bizarrely, the footage of the TV displaying a 3D image appeared in 3D on my TV, without the need for glasses. What this shows (and, indeed, what projecting any 3D image on to a 2D surface shows) is that there must be a way of making a true 3D image on a standard CRT. Maybe the computational power is too much right now, but I can't help thinking that if you can get an image that looks 3D on to a flat surface, there has to be a way to display one on a monitor, without any special hardware.
Like car accidents, most hardware problems are due to driver error.
The two images are projected over each other, so it doesn't matter where the are, as long as they are close enough to each other (and there is enough room for ventilation and so - their first (plastic) polarizing filters melted from the heat).
Teenagers these days don't have as much sex as they want each other to think they do.
Since such projectors are likely to have a lot of compromises.
On the other hand, it's theoretically possible to make projectors more suited to a task.
Finally - Search hard enough and you can get used LCD projectors for $1000. Resolution will be a bit low tho. I'm assuming 90%+ of that $12k was for the projectors. (Maybe only 80% - They did use a Quadro4...)
retrorocket.o not found, launch anyway?
Your in heat? You stupid fucking moron. How about "you're" fucktard.
there must be a way of making a true 3D image on a standard CRT. Maybe the computational power is too much right now
Viewing 3D means that each of your eyes sees a different image. You can't do that on a standard CRT no matter how much computer power you throw at the problem. If you go to the linked site, on of the first things he does is explain how we see 3D.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
To be able to view 3D images without 3D glasses is crucial to the success of such a system, especially if it is to be marketed to consumers.
... Too difficult and intractable. How do you know you see a small tree from close or a large tree from far?
I don't think you are right. It's just an extra bit of hardware, like a mouse or kbd. The important thing is 3D images. As I said in a post below, these systems are used to view 3D models. Faking 3D from 2D images is something completely different.
if you can get an image that looks 3D on to a flat surface
Have you ever seen a movie? Doesn't it look 3D? Perception of 3D from 2D images is known since the renaissance with methods such as perspective. What you want is a real 3D model from a flat source. Then you have to estimate the respective distances between every points on an image and extrapolate what is on the other side of objects,
I'll do it for cheesy poofs.
Actually, I know they did: The Wedge. A much more immersive version of it too. Granted, the wedge uses the expensive Crystal Eyes glasses for stereo instead of polarised glasses/projectors, but the basic principle of cheap VR is the same. Why don't people who set out to make a cheaper better solution start by doing a bit of web surfing!?
omg. lol. I r L337. u r0x0rz.
Taco, we know it's you.
Try NetBSD... safe,straightforward,useful.
I found it interesting that they would pay ~$500 for a cart, ~$100 for a surge protector, and then be blocking up the projectors with dry erase markers and holding them in place with nylon straps. Some more careful management of budgets could probably bring this project in under $10K.
SablKnight
Sure you can. Get a stereo emitter and stereo LCD glasses (such as Crystal Eyes and a graphics card that supports it and off you go. Note that you'd like a CRT that goes 120 Hz, to reduce flickering, and that the graphics cards that support stereo are the pro cards, i.e. pretty expensive.
Bizarrely, the footage of the TV displaying a 3D image appeared in 3D on my TV, without the need for glasses
So - when you moved from one side of the TV to the other it looked different? Did it?
No.
It didn't did it!
doghty at school used to tell us his dad had a 2 wheel drive motorbike. Your not doghty are you???
hrm. I'm about 8 years out of the classes where I could have calculated this, but doesn't diffuse reflection (as used in projection) destroy polarization?
I had assumed that these guys used alternating l/r images and synced them up with lcd shutter glasses, but apparently not!
I don't think you are right. [3-D glasses are] just an extra bit of hardware, like a mouse or kbd.
The biggest problem with polarized or shutter glasses, as I understand it, is that there's enough "leak-through" of the other eye image to damage the 3-D illusion.
Head-mounted displays have no problems in this respect, but have the problem of making the focal distance far enough away from the viewer that they don't cause eye fatigue or destroy the illusion of distance to the objects.
Have you ever seen a movie? Doesn't it look 3D?
Apparently the video release of "Gosford Park" used some sort of post-processing on its images to try to enhance the 3-D feel of the movie. I watched it and can't say it really jumped out at me, but I would have liked to have seen split-screen or before and after demonstrations of the effect to get a better sense of what it did and how effective it was.
Ooh, a sarcasm detector. Oh, that's a real useful invention.
I bought the revelator stereo glasses from, ELSA I think? They work with almost any card, but definately any NVIDIA derivative. I got it originally with my TNT2 -- oh god that was useless! But still, with those you don't need the 'pro' versions.
Sure this is cool, but is it useful? 2D screens are old hat, and seem to work well. People play doom and other 3d games on them without problems, so we can fake the 3rd dimention if we try.
I can't be the only person who gets sick watching 3d films. I've only done it a few times, but that is enough that I refuse to considering doing it again. If 3d films become a major part of education, then I'm disabled because I cannot watch them.
Sure you can.
Minor mis-communication. Either I wasn't clear, or you missed the context of the post I was replying to. The parent poster was claiming he saw 3D on an ordinary TV. Read "standard CRT" as "naked CRT", no glasses.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
I bought a set of Revelators on their own before Elsa went out of business, and now I've got a GF4 and suitable new drivers they're working again in "bitchin' high framerate 3d" kind of way. Works in any opengl or direct3d game under windows - getting railed has never been so personal.
ahh...this reminds me of 10 years ago when I hacked an Amiga Video Toaster to record interleaved 3D video from 2 cameras and play it back through LCD shutter specs.
Those were the days...
"Follow your Bliss." -- Joseph Campbell
I bet you could do this with one projector if you could add three more signal components: polarization for R, G, and B.
Then you can have a graphics card that generates an RGBPPP signal from two frame buffers.
Then again, maybe you could accept two RGB signals in the projector and choose the polarization there.
If anyone wants to patent this, I demand a cut.
The $10K setup described uses polarized projection, which is pretty good but requires a straight optical path. To make a 6' image you need 8-10 feet of throw distance - no mirrors allowed. A full wall (8-10ft) requires even more (I dont have the ratio handy, see projector specs). Front projection means you can cast shadows on the screen, which might be used for tracking/interaction but interfere with the 3d immersion/presence effect. Multi-walled setups require a LOT of space - or active stereo, which means more expensive projectors ($50k+) and gen-lock sync between video sources (not available for nvidia, ati, matrox 3d cards - sorta see links below)
Tracking is another big problem left out in this implemenation. Mag trackers mentioned in another comment are one solution, although the interference problems are a big pain. My choice is the Intersense IS900, but it starts out at around $20k.
For more on low cost immersive projection environments see Dave Pape's course notes
For more info check out my Siggraph2002 report and my vr info site
Jerry Isdale
Oh, gotcha. My mistake.
"Sounds to me like you're a bunch of jealous incompetents... "
Shut up or we'll sue you!
I'd like to look it up.
My college had mobile projection systems somewhat like what you describe and a bunch of them were stolen last semester. Evidently their compactness and cost makes them a hot item. (" 'scuse me, young man, could you show me what is making such a large lump under your jacket? ")
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$10k? Bah!
Drew Olbrich has a much better idea. Nothing like 3D Asteroids!
- grueThis is rather like the random-dot stereograms, but inverted left/right from that arrangement. In the RDS, you RELAX your eyes, the opposite of crossing them. I personally find this difficult, so I swap the images so crossed eyes produce the correct left/right arrangement instead.
Incidentally, I used to fly Microsoft Flight Simulator back in 1988 this way - yes, version 1.0. I discovered that I could set two different forward views from the Chase Plane mode, with one plane offset slightly to the right and the other slightly to the left. By properly arranging the windows and crossing my eyes, I could fly around looking at the simulated world in true 3D. I believe you can still do this with the different window options available in Flight Sim, and you could probably do this in any game that allows you to set up multiple windows from different viewpoints.
Now, granted, it is tough on your eyes, and it's kind of hard to see any non-stereo items (like the control panel), but it IS 3D and requires NO hardware. From time to time I do this for other purposes - like the picture above.
You can also do this with any camera if you have a still (or mostly still) subject - take a photo, move sideways about four inches and take another. Then load both photos into your image editor of choice, position them side-by-side with the proper left/right orientation, and you're set.
--Brandon / Split Infinity Music
Tho I may have mispelled it. It's a mini-cave system, complete with tracker and small enough to fold into a crate for shipping.
CAVEs can also be shipped. Setup and teardown time is pretty harsh but it can (and has at NCSA/UIUC) been done.
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Hey,
"This summer I helped built a Geowall stereoscopic projection (3D) system for the Southern California Earthquake Center."
Do you need any help to test your 3D Quake Simulator? If so, call 1-800-GAMERSINC
Thanks,
Michael
"Goodness me, how unlike the FBI to abuse the trust of the American public." -- The Onion
Ouch! Slashdotting the scec.org website 4 days before our annual meeting. How am I going to find out what hotel I am staying in?
The basic idea is sound, but if you want a really cheap 3D projection system, use a couple of old LCD projection panels + overhead projectors. You can find a lot of these things on Ebay. Proxima made the best ones AFAIK. Overhead projectors are big and heavy so you might want to look at a local auction instead. So now, you're looking at a cost of perhaps..
100x2 lcd panels
50x2 overhead projectors
30-50 quality polarizing filters
5ea polarized glasses
50 old silver screen
150 dual-head radeon 8500
Around $500-600. Much better. Now it's truly a 'poor man's' 3D projector. And to think some people would spend that much on a 32" television!
It's been tried before, and done. The real problem is that an ideal stereoscopic projection is different for each viewer - it depends on the distance between the eyes. It's also difficult for an individual to judge when a stereoscopic projection is properly calibrated to their vision.
And if it's not properly calibrated, within half an hour, you have a real killer headache. Combine that with the fact that we are already really good at picking up 3-d visual information from 2-d projections, and I don't see this going much of anywhere in the near future. Especially at $10k.
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Avoid in general, mostly because its meaning is often confused. It means "include" or "contain." Depending on your meaning, use those terms or consist of or make up as appropriate. Do not use comprised of.
Karma
Have fun!
The problem has already been worked around, although in a reverse manner.
The autofocus and metering systems in modern cameras do NOT take kindly to polarized light.
So how do you use a polarizing filter? A circular polarizer. Basically, it consists of a linear polarizing layer followed by a quarter-wave retardation plate of some material that will take the polarized light passing through the filter and convert it to circular polarization. (Not sure of the exact mechanics of how it works, but in short they somehow convert a linear polarization to circular.)
So one would simply need to do this in reverse with an LCD projector - In fact, one might even be able to use circ polarizers designed for cameras.
It will probably have higher loss (reduced brightness) than a system with a DLP projector, but it should probably still work well.
I'll try it tonight with my 72mm circ and my projector.
retrorocket.o not found, launch anyway?
"Traditional stereoscopic projection systems like The Cave which is used primarily for new product modeling and on a few university campuses cost anywhere from $150K to $1.5M. They are built into a fixed location, often requiring significant architectural modifications, so transportability isn't even an option."
The CAVE is transportable. They have a version that SGI brings to a lot of military tradeshows, and I've seen it at the last few AUSA symposiums that I've been too. Its not _EASILY_ transportable, but they do move it around to different shows.
Has anyone produced a left-eye/right-eye differential version of DOOM?
Because 10k for stereoscopic DOOM is well... within the realm of daydreams at the very least!
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Now I could be wrong but as I understand the writeup the user is using a rather expensive converter to send the images to the projectors. Couldn't a Linux box with two xservers running and 2 video cards (or two linux boxes run by a master system, a mini cluster) do the same thing for under 4000?? I am not a Linux Guru by any streach of the imagination. But if that worked it would be a heck of a lot cheaper then the 12000 buck converter.
Take one of those 3 DLP projectors; remove one of the panels; make the remaining 2 panels full function color; and then put high-efficiency polarizing filters or splitters/combiners (preferably circular) into the internal projector path.
Now we would have a fully pixel aligned, efficient, single-box, passive stereo projector that could turn into a mass-produced item for us all.
Then do this for native 1920 X 1080 DLP chips...ASAP.
Would be sweet!
MJR
PS...More Geowall assembly instructions can be found at the eMedia Center Geowall/AGAVE Development Project site
It seems that, tho I like what they did, it could have been better.
The problem with the "no software implementation" for sending the images to different monitors? Tho still grounded slightly in hardware, wouldn't it have been easier to just use two cards?
And, tho i understand they can afford it, when I get around to trying this out, I'm making the projectors myself! A nice google search tells you all you need to know.
The first point I made solves this one: they didn't need to do so much image editing. Not to mention, aren't the image files timestamped? That should help with the ordering... And most camera software lets you specify filename prefixes.
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