Hi all,

I've been using 85hz DLP projectors exclusively for my 3d solution over the last 2 years, and some of you may have already seen the latest thread for my sterescopic home simulator project which all of this has yielded:-

viewtopic.php?f=3&t=2907&hilit=home+simulator

There were a bunch of issues to get around to make all this work with the greatest effect, a large one of which was the slight timing differences (and eye reversing etc) which are inherent with using consumer 85hz DLPs (which have different signal propogation times in their electronics). This would result sometimes in significant ghosting and inverse parallax, which could all be resolved with some circuitry to delay this signal.

Following this I sat down with a friend who is an electrnoics engineer and he offered to put together a delay controller with me to test - this was completed a few weeks ago and yielded such excellent results he's offered to build these to order for anyone that wants to use 85hz dlp's with shutters.

This dongle works with all 3d-capable 85hz dlps I've tested (namely the Infocus X1, Sharp XR10-x, BenQ MP721 and others, the full list can be found at:- http://www.stereo3d.com/cgi-bin/discus/ ... ?3177/3347). The great thing about it is it has a standard VESA output, meaning it will work with shutter glasses such as the following flawlessly, you just plug this into your vga port then your existing IR emitter straight into it:-

* nvidia 3dvision - Plug the output from this into the VESA input in 3dvision glasses to resolve sync issues using these with 85hz DLP projectors (this is a great solution, as there is significant ghosting and eye reversal when using 3dvision without this).

* eDimensional (wireless) - replaces the eDim VGA dongle completely, just plug your little IR emitter into it.

* Stereographics CrystalEyes (2/3 etc)

* ELSA revalator

In all the time I've spent using DLP's such as this, this is the product I've been looking for and finally all my glasses technologies (CrystalEyes, eDimensionals and 3dvision) work flawlessly with all my projectors (Infocus X1, Sharp XR10X and BenQ MP720P). Personally I will _NOT_ fork out thousands of dollars for a DEPTHQ with inferior lumens output, and 85hz is extremely comfortable for me, I personally notice no flicker in 99% of scenes and can use it for days on end without any kind of headaches or eyestrain.

If anyone would like one of these, I've asked Neil if it was OK to post a link here - they are built to order with a lead time of 2 weeks and the order / pricing info is on the following page:-


http://nextstepsolutions.co.uk/home/node/11


Hope this helps, finally I have flawless projected 3d using my GTX280 on 3 screens, hurrah! Any questions please feel free to PM me or contact James at the link above.

Happy big-screen 3d'ing!
Chris

Wow. Sweet.

I know my projector does 85hz at 1024x768.. but it's an LCD3 projector from my understanding.

Do you think it would work ??

http://www.tigerdirect.ca/applications/ ... CatId=1755

Cheers !

Hi, afraid not - you need to use DLP projectors due to slow LCD response times - any of those on the page I referenced will work great and can be picked up on ebay these days very cheaply

thanks for the link Chris! I will be ordering one .Finally I dont have to wear the glasses upside down and having my wife laugh at me ......well not as much. I assume this works with the Matrox THTG.

Hi,

Yep - works fine with TH2G (I am using it with a TH2G digital).

Hope this helps,
Chris.

I will be ordering one as well, still don't have the 3d vision, but it has appeared on ebay, so I'm debating whether to get a set of glasses that way, or wait to see if the rumored april release in Europe is true...

Just to confirm, if you don't have this dongle, you will still get stereoscopic - it's just there might be some ghosting issues etc? Many people have reported using 85hz projectors (without this hardware), is this because they're using the old stereoscopic drivers (Geforce 7xxxx)? I read the latest Geforce cards don't have the stereoscopic drivers required for this setup, so is this dongle used to get the latest Geforce cards working with Nvidia 3D vision? Will Nvidia 3D vision work at all without the dongle (on an 85hz display)?

Also Xerion you mention in your sig "E-Dimensional & AnotherEye 2000 wired shutters with Sharp XR-10X". What are the current problems with this hardware configuration, that the dongle will solve (as you're interested in getting one)?

I'm looking at getting the Sharp XR-10X, just wanting to know what hardware is required - I couldn't seem to find any user guides on how to set up an 85hz projector for stereoscopic 3d.

Finally, are the CrystalEyes better than the Nvidia 3D vision?

Cheers

Hi,

Yep 85hz DLP's can be used with the older nvidia drivers without so many problems (though there are some projectors even with these drivers which yield a little ghostinig only correctable with a delay dongle). With the new 3dvision drivers, there is a more noticable delay which results in significantly more ghosting, certainly on the projectors I have which are the Infocus X1, BenQ MP721, MP720p and Sharp XR-10X (the XR10X is the worst actually). Just to give you an idea, what you are speaking about here is the exact solution the dongle was built to fix in the first place (from my personal perspective) - to get the 3dvision solution usable with 85hz projectors. With this dongle, you can either use your own VESA glasses, or plug its output into the nvisions VESA input (overriding the sync signal coming through the USB line). You will need this kit for the following reasons:-

1) So you dont have to wear your glasses upside down if using the 3dvision ones.

2) To elimiate the ghosting which is enough to make games as good as unplayable in my experience.

3) If you want to use other glasses with 3d vision via the VGA port. The main reason is you can never predict which eye will be in which frame buffer when a game starts, so sometimes the eyes are reversed, sometimes not - you therefore need the quick toggle switch to flip them correct again and they will stay the right way round until control returns back to Windows. It is also for this reason that you cannot use any other existing VGA dongle without a reverse switch (e.g. eDimensional). The 'eyes reversing' wasnt so much of an issue with older nvidia drivers, as there was a DDC square wave signal output on the VGA port to indicate to a VGA dongle (such as the eDim one) which eye was which - this sync signal does not exist with the new 3dvision drivers (as they only 'officially' support the USB dongle and not other glasses), so the quick reverse switch is needed. Again, it is important to note once the reverse switch is flipped to get the eyes the correct way around that they will remain correct until the game is fully exited (I have tested this thouroughly and not once had a problem).

In terms of CrystalEyes vs nVision, CrystalEyes have always been, and still are the best at the moment (which is why they cost $600 or so just for the glasses). BUT, 3dvision are definately good quality and worth the money, plus they have their own rechargable batteries and decent sized LC panels - however they ghost slightly more than the CE's and the CE's give a more natural color result.

I've been trying all types of different combinations for the last couple of years, and my highest recommendation in terms of value for money / performance currently goes with the 3dvision solution used with the VESA delay / reverse dongle - it is a solution many people have been looking for for some time now.

Hope this helps,
Chris

I sent a mail to order one. The reasons have been explained by Chris well enough

Thanks, that was just the detail I was looking for.

I believe you've mentioned the SharpXR-10X (not XL) to be amongst the best projector for stereoscopic (at least with Geforce 7xxxx). For Nvidia 3D vision with this dongle, what projector would you recommend out of the models you listed (Infocus X1, BenQ MP721, MP720p and Sharp XR-10X). Is there much of a difference?

Cheers

Hi,

To be honest there is not a lot of difference - the XR-10X strengths are its 4x colour-wheel speed mean a perfectly even colour balance in each eye (there is a slight colour difference between eyes for the BENQ's and Infocus, as these use a 3x color wheel speed which results in an uneven colour-pass), but at the same time the XR-10X lamps are quite a lot more expensive and it has a slightly lower lumen output. I find the BENQ's to give an overall slightly more natural colour result but that is a matter of personal preference. I can't really recommend between the 2, depends what the best deal you get is I suppose - they both yield fantastic quality results at the end of the day

One thing to note if you do opt for the Sharp - be sure to confirm it is definately the XR-10X model and NOT the XR-10XL as this is incompatible with 3d @ 85hz (and there are sellers out there who have been known to sell the XR-10XL as the XR-10X as it is approx the same in terms of specs).

HTH,
Chris

hi Chris,

So you are Saying with one of these Gizmos I will be able to use the new nVidia 3D Glasses and my DLP Projector?? I will still need to use Vista as well??

Hi,

Yep thats right (assuming it is on the list of known 3d-compatible 85hz consumer DLPs) And yes, unfortauntely you will still need Vista until Win 7 is officially supported, by which time anyone using Windows XP will prob want to move to Win 7 anyway, being a superior operating system!

Although NVIDIA state support is only for '120hz CRTs', these glasses do actually operate perfectly at 85hz also.

Chris.

Hey Great glad but I have 1 problem I have the XR10XL Version Projector and can Only game @ 75Hz really for me it isnt bad I barely Notice the difference Lucky for me so will the Glasses still work in 3D with this model Projector??

I can game now in 3D @ 75 Hz and it works for me..I know 85 would probally be better but I dont notice the difference is there more flicker or something Please Explain the difference..

I am trying to get a 3 Projector setup and going to buy 2 more XLs but if this will NOT work with the new Glasses I am going to have to get the BenQs or something what do you reccomend??

Semms you caught some crap from someone over at the nVidia website Poor Fool doesnt even know what he is talking about.. he must have some very Sensetive eyes to see the flicker at 100hz and still noticible at 120hz ??? you played it out nicely Good Show

hehe yeah I know, I have to admit I was surprised to read what he was saying, in another thread he was asking if the glasses could be pushed upto 160/180hz - I think he really just needs to try the projector method out, I personally can't bare to use a CRT and all sorts of things give me headaches there!

Re: using 3xXR10XL's at 75hz - I don't really see too much of a problem with this, however you need to confirm the 3dvision glasses will operate at that frequency first. The dongle should without a problem (drop Jim a mail at NextStep Soltutions for verification), afaik it should work 60-120hz without issue. So long as both these come good then using 3x10xl's should be fine. One thing about using BenQ's with a triple setup is sometimes its a little fiddly due to the colour difference between each eye - worst case scenario is 2 will be in sync and one not (ie 2 are slightly bluer in one eye and redder in the other, and the other is the reverse) - to rectify this you need to unplug and replug-in the VGA lead to the projector (or switch it off and on again) until it comes back into sync with the others. However, you at worst only need to do this at the start of a gaming session (they will stay sync'd until control returns to windows). With the XR10/XR10XL's you have no such issue. If you can though, do try and get a couple of XR10x's instead of XL's cos you may always be thinking 'yeah but it could be slightly better' else

Incidentally, many people on these forums will already be aware of this excellent whitepaper, but if anyone here would like further information about any of the tested / supported projectors and issues discussed here please refer to the following:-

http://cmst.curtin.edu.au/publicat/2007-05.pdf

Hi chris, out of interest have you tried this delay box on some standard lcd screens/projectors? Assuming the polarization is sorted out maybe adjusting the delay could get some result with a lucky lcd?

Hi Otka,

I wouldn't rule it out completely, but that wasn't really the intention of the original conception - others have asked this already, but I would have thought with LCD's the problems lie more in the issues discussed in the artilcle I've referred to in my last post. I haven't tried anything personally yet may give it a go if I have some time to toy in the near future.

Sorry I can't help more with this,

Chris

Yeah i did read that paper some time ago but it would be fun to try some lcd's. Who know's, maybe some screens can give a decent result. Could do wonders for the delay box sales, I would love to have shutters working on my 28inch

Hi Fellas,

It's nice to see you got everything working chrisjarram.

FYI for everyone, I uploaded the schematics of exactly such a device back in the stereovision forum days, and again here when this board came to life. The post can be found here:

viewtopic.php?f=26&t=25

If you are confident enough with a soldering iron then the obvious advantage is that it costs about a dollar to build. Signal is on Pin 12. The signal flipper is just any run of the mill inverter chip... you can get about 8 inverters on a single chip for a few pennies.

Also at the bottom are notes on how to convert it to make a stable signal generator to remover flicker issues as in "error in the signal" (not the other type related to low refresh rates). This generates a constant signal for perfect stereo, and syncs to the display by using the DDC signal as a "Reset".

Obviously as with anyhing else this is always an option if you are an experienced engineer and want to cut costs (a 'dollar' is a bit optimistic here though I have to say! ) - however please be aware the unit for sale is of an extremely high quality using surface mount components, and is built and housed in a high quality casing by a fully qualified professional electronic engineer, which is where the additional costs are incurred - the actual markup is not that great on the finished unit. It is also assured to be safe and has been thouroughly tested in multiple situations, and is excellent value for money compared to some other similar commercially available dongle solutions on the open market. IMPORTANT - if you are considering building one of these yourself, be warned it is EXTREMELY easy to permanantly damage your graphics card if you do not know exactly what you are doing, as GC's are highly susceptible to poor earths, static discharge or incorrect line voltages; it does certainly require more than just confidence with a soldering iron, as a number of people have discovered the hard way in the past with costly results (which is precisely why I personally chose to leave it to an experienced professional rather than zap my GTX280!). Many people purchase the 3dvision solution these days to use with high-end graphics cards like 8 series and above which are not cheap, so do so at your own risk!

Not quite that risky in my opinion as you are using the voltages supplied by the graphics card itself. Granted, if you have other voltages from elsewhere with which to short something with, there would be a danger. But there is always an element of risk in any DIY project. In fact, i would go as far as to say that it is part of the fun.

But I digress. What I want to ask you is, how do you deal with the yellow tint in one eye at 85Hz on the 720p? At 60Hz, the colours are fine - I find myself using 60 Hz for gaming over 85 as I would rather have flicker than colour tint.

Perhaps you don't find it distracting or have managed to fix it some way?

If so, I would love to know how

I can't see that frying a $600 graphics card could be a great deal of fun but that's all you! In terms of other voltages, it really depends what kind of emitter hardware is being used and what precautions have been taken against static discharge overload, and I know from first hand experience the dangers of doing this (a couple of years back I blew a 7 series g-force with worrying ease from just such a thing) - anyway it is just a warning to anyone tempted to try... If you want a high quality product that works well and is safe, this is a good choice... I am making no money out of this and the engineer building them is being paid a nominal fee for his time, it is definately extremely good value for the quality of product you will receive (no breadboard here!).



There is no fix for that no, if you read the whitepaper there is a good explanation as to why this occurs (it is a physical hardware limitation). 99% of the people I've spoken to do not find this distracting at all, as the brain balances out the colours between the eyes rendering it as good as unnoticable anyway (certainly I cannot tell unless I close each eye and explicitly look for it). If it really bothers you that much, I'd recommended getting your hands on an XR-10X which does not suffer this issue (or fork out $6000 or so for a depthQ HD! ). Personally I'd take the 85hz with slight colour inbalance over 60hz any day, I simply cannot bare to play at 60hz!

Colour difference is the big thing that bothers me... I can get used to ghosting, low refresh...

It all started when I bought an i-Glasses SVGA 3D - the worst 3D purchase that I ever made. The colours above 60Hz were unbelievably bad, and they didn't tell you about it.

Then it happened on the 720p... and on the iZ3D. I wonder what it is that causes all these technologies to turn one eye specifically a darker yellow colour... perhaps I will read that white paper you mention.

Luckily though, iZ3D sent a few of us some Beta glasses which completely fix the tint and now im a happy gamer on the iZ3D. But if I can get most of todays modern games to run at over 60FPS with everything maxed then I would play on my projector again.

Tell me Chris, Can your engineer friend design or modify the current design to encorporate a chip which will sample the colour lines and refresh signal, and combine them to detect the iZ3D colour coded frame output for pageflipping, and then output a DDC square wave signal to an emitter or a wired dongle so that each frame would always be in sync to the correct eye even at frames below 60fps with minimum possible signal related flicker at point of inversion?

You obviously need a data capture oscilloscopes to work with for diagnostics etc, which I don't have or I would make one of these.

If you can make it, it wold be infinitely more useful to us and be in BIG demand (looking at the shutter glasses thread in the iZ3D section).

I would happily pay £200 for such a device.

After the initial microcontroller program has been designed, the production costs of multiple items would be minimal.

Perhaps speak to your engineer friend?

If he thinks he has the time, perhaps you can start a new thread and gauge interest in the device. I honestly think that it would be a rewarding and proffitable venture for the time and effort you would put into it, and a great thing for our community and Stereo3D in general

-- Shahzad.

Hi again,



Well, with my MP720p's (all 3 of them), the only slight colour anomoly is one eye is slightly bluer than the other, that's it. It is not remotely noticable unless you are looking for it, the colours are as good as flawless - so perhaps there was something wrong with your projector also? :-/ One thing that may be worth noting is a lot of colour anomolies can also be caused by shutters themselves - for instance I get significantly more natural colour results with my CrystalEyes than with the 3dvision glasses (which are more yellow), but even this is only noticable when comparing the glasses directly side-by-side. Just seems a bit strange what you are saying as it really is very, very minor indeed for me - to the point of being a non-issue.

The colour difference between the eyes is easily explained for DLP projectors at least, it is simply a result of an uneven colour-wheel segment pass per eye, due to the timeslicing of the individual frames - this is explained diagramatically in the whitepaper referred to. In terms of iz3d polarization, I don't really know (other than it is for completely different reasons) - all kinds of colour effects can result from polarising light so it doesnt surprise me.



I actually worked with iz3d at the early shutter support stages to get this working with the stereographics seteroenabler, with reasonable results. It is not a _bad_ solution, and works ok for some glasses, however the main issue is there are many LCS glasses which simply do not operate below certain frequencies (the CrystalEyes being one for example, which stop working altogether at below about 70hz). This means that if your framerate does drop below 70hz your glasses stop working, and in practice this renders games unplayable. From all the testing I have done, by FAR the best solution is to use the 3dvision glasses in conjunction with the existing VESA dongle described here. Yes, you lose openGL support for now (which is a shame as I like that about iz3d), but you always get flawless refresh rates completly uninterrupted, and there is no problem with eye-ordering as you simply flip a switch _once_ if a game starts with the eyes on incorrect sides, and do not have to worry about it again until control switches back to windows and you load another game. For most people, gaming at and below 60hz is impossible, and I'm not sure by your comments (e.g. 'minimal signal related flicker at the point of inversion') that you've fully understood the issues there are with such a solution. At the moment, all that is needed is a stereographics stereoenabler (I still have mine) - I do not see how there is anything you could add to this to acheive better results, unless I am missing something? We did originally consider making this unit to be a VESA pass-through in order to support conjunctive use with something like the stereoenabler, but that requires a separate VGA pasthrough dongle to pick up the V-synch and convert it to VESA - and all it would gain is the ability to delay the VESA output signal slightly. If there is something I've overlooked please do elaborate however, if there is anything that can be done to improve on existing technologies I'm definately all ears!

Thanks for the input!
Chris J

Hi Chris,

I had emailed James and he said he did Not know if his Gizmo will work @ 75Hz he said he will ask you do you know if it will work @75Hz??

If you do Not know Who can I ask??

Perhaps I was a little unclear.

3dvision is not an option for me, and I believe for most stereogamers, as it requires Vista, which we are not willing to "upgrade" to.

From what I understand, the stereographics StereoEnabler only generates a square wave which mimics the signal on the DDC line sent via the old nVidia stereo driver but does nothing in the way of fixing the LRLR sync issue with the iZ3D page flipping mode when FPS drops (or does it? I've been happily gaming on the iZ3D for so long that I have lost track of new S3D developments).

I use Elsa revelators and ED glasses which have no problem with 60Hz.

I want something more. I want something which will automatically detect which image is intended for which eye and automatically adjust the flickering of the shutters accordingly. I don't want to do it using a manual switch and I want it to work with glasses that do not use line coding - only the square wave on the DDC line.

From what I understand, the blue line coded shutter mode in the iZ3D driver displays a blue line code at the top of the screen in a frame intended for e.g. only the right eye.

This means that, with the help of hardware which can sample the current refresh rate, the blue line can be sampled to see if such a line exists at a point in the image. If it does, then the frame is intended for the right eye and it can generate the square wave in such a way which allows the shutters to automatically adjust the sync so that the image will indeed be only perceived by the right eye. When there is a glitch i.e. low fps flips the images, the glasses too will automatically be inverted so that a seamless stereo image is presented.

So, now where previously the screen will be displaying:

RLRLRLLRLRLRLR
-_-_-_-_-_-_-_

the signal will automatically change to:

RLRLRLLRLRLRLR
-_-_-__-_-_-_-

Do you see what happened? Please tell me if I need to make it simpler.

This is the part where the flicker related to bad DDC signal comes in. When it is consecutively low, the glasses hardware might not be able to handle it instantly and might freeze/shut off for a length of time while it re-adjusts, where the glasses will seem to cause a "flash" because of the lost sync. We want to eliminate this possibility, or minimise it to as much an extent as possible.

Still with me?

The obvious problem is that we seemingly need to buffer some frames so that it will always be in sync - The frame will always need to be in the process of being output while it is being sampled and we will not know if it is a correct sequence or not until 2 consecutive frames have finished being transmit - at which point we can flip the signal if both the previous frames contained a blue line or did not include a blue line but it is now too late as a wrong frame has already been transmitted into the wrong eye.

To overcome buffering, I suggest we ignore the single frame altogether - i don't think it will be very noticeable at even 60fps.

What we will have to do is sample the refresh rate and work out the time for each complete frame. From here, we calculate what fraction of the screen the blue code is, and by multiplying this by the time for each frame, we will get a value for time that the blue colour transmit line needs to be sampled from the top of each frame to see if there is blue code at the top of the frame or not - we will need an MC capable of analogue to digital conversion for sampling the blue colour line of course.

So, in the end, this is what will be displayed on the screen and what the square wave that is output will look like:

RLRLRLLRLRLRLR
-_-_-_--_-_-_-

At the second consecutive L, the signal cannot flip because the frame that is being sampled is already being transmit. But, we can then flip the signal for the next frame, assuming that it will be R.

So what would happen if there are 3 consecutive Ls?

RLRLRLLLRLRLRL
-_-_-_--__-_-_

What we see is that the sync will always be correct no matter what happens - minus one frame which will have to be displayed in the wrong eye (unless we use frame buffers which will add too much complexity), which I hope will be un-noticeable.

Please tell me if you don't understand a part and I will try to make it more clearer.

I think we can both agree that having to manually flick a switch every time the display sync changes would detract from the game experience - the whole point of s3d being immersion.

-- Shahzad.

Hey Chris

I totally down on getting one of these if you can say it can use both the Nvidia Glasses and the Edim Glasses at the same time with no cross interference. Have you tried this? I have a Benq721 and the Nvidia glasses suck with it (reverse and ghosting). If I can get both glasses working same time this is the perfect item (although I dont think this will work.)

Cheers
Damien

Hi again Shahzad,

Thanks again for your input, in terms of the stereographics stereoenabler - you are misled, its pupose is to detect marked frames (using the stereographics BLC format) to identify which frame is which per eye - the bottom raster line is 1/3 black for the left eye (and 2/3rds blue), and the opposite for the right eye.. in terms of the other points you raise, fortunately it just so happens I have James with me now so here is his response to your queries:-

Hi all.

Shahzad, I see your point about losing sync but I doubt that a VGA card would stall in such a way. I may be wrong but...

In terms of getting the right eye on the right frame, I see current systems as, shall we say, sub-optimal. The problem is that (for some reason) there is no single signal in the VGA set which flips on alternate frames. If there was, and there's plenty of scope to do so - the depracated ID lines for instance, then life'd be much easier.

We're currently working on a device that can understand blue-line keying and we'll keep you all informed on our progress.

ATM all one can do is run off the VSYNC line and accept that for 50% of the time you'll be on the wrong frame - that's what the switch is for! Having got it right once, the whole game session should be right until you return control of the card to win"$ws. Thereafter you might need to switch again... The concern you have about dropping single frames, causing de-synchronisation, is valid but not likely as far as I can see.

I'm surprised about your comments re DDC. As far as I'm aware there's no synchronous involvement between the graphics signals and DDC. DDC is just a version of I^2C and is used to detect monitors' capabilities. If it is used, and it could be, for sync'ing tasks then I've missed something so please let me know.

All the best,

J

Hi Chris,

Thanks for the reply and clearing up the StereoGraphics option. Like I said, I have been happily gaming on the iZ3D for a long time. The only thing that peaked my interest in projected Stereo3D again was the nostalgia from the ghosting fix device.

This device may just be exactly what I am describing. Please can you elaborate on the format of the sync signal produced? Is it a square wave?

The website does not seem to go to any great depth - What I want to know is will it work with cheap ED/ELSA Revelators or only their $600 glasses





I guess you would have to be a stereogamer to know but this is exactly what the DDC signal is modified by the nvidia cards to do:

nVidia Stereo3D and ELSA stereo driver used to use one of the DDC lines (specifically pin 12) to generate a square wave form such that High was a signal to the emitter/dongle that one eye should be closed on the glasses, and low would be a signal for the other eye. Flipping this signal would obviously invert the parallax.

In fact, in my design of the ghost removing circuit, this is the signal that is being modified - I do not reference the VSync - perhaps why it is so cheap.

The signal on the DDC line with Stereo enabled on the old nVidia driver would look like this if you were to put an oscilloscope on it:

-_-_-_-_-_-_-_-_

The ELSA revelators and ED glasses (not sure how many others, if any) used this signal to sync to the display.

Advangtages being that no hardware was needed to convert the VSync signal to the square wave form which the emitter could understand, and the frame sync would be correct for parallax 100% of the time at game start (which I am not concerned about). As James said, there is no signal that is flipped on alternating frames in the VGA set, but the nVidia/ELSA driver modified it to be so.

Please allow me to be clear on one point. I am NOT talking about flipping the switch so that at the beginning of each game session there would be correct parallax for the rest of the session. The problem that I am concerned with is when using page flipping mode with the iZ3D driver and at any point in the game where there are low FPS, there is a chance for the frames intended for each eye to miss sequence ie instead of RLRLRLRLRL it might show RLRLRLLRLRLR. The 2 Ls mean that at any given point in the game where the FPS drops, the parallax is inverted because the square wave being sent to the dongle is not corrected for such a mistake. The sole purpose of the hardware that I am talking about is to correct this issue only - to correct this anomaly in page flipping mode when using the iZ3D driver.


If this signal was to be altered to be compatible with the iZ3D Blue Line code AND to keep sync even if the frame sequence were to falter at low FPS, it might look like

RLRLRLRRLRLRLRL <-- faltering sequence
-_-_-_-__-_-_-_ <-- signal adjusted to prevent parallax inversion

The consecutive lows (or consecutive highs) might cause the glasses to freeze/shutter garbage, or desync for a fraction of a second while the dongle readjusts - it would be the hardware in the glasses dongle that interprets this signal that would mess up, not the graphics card. This is just conjecture of course, but it is a big possibility. It might cause a flash and that is what I want to avoid.

If the stereographics enabler generates a square wave such that it would be compatible with the ELSA/ED, then this is exactly what I am looking for and is exactly the hardware that I described in my previous post.

If not, then I am optimistic about:



That is pretty much what I would be looking for - my previous post was largely a description of a method to make such a device. I hope there would be a version available which does both ghosting removal and blue line code

Thanks again,

-- Shahzad.

Hi again,

Yep the Stereoenabler outputs a standard VESA compliant signal, so will work with all VESA compliant emitters (including revalator, edim, crystaleyes etc). I have one here but don't use it due to the frame rate / refresh issues - still though you may have better luck.

HTH,
Chris

Does it have to be a hardware dongle for the blue line code? If someone knew how to wire some glasses to a usb port we could write some software that grabs the screen an interperates the blue line code to turn the shutters on and off at the correct frequency.

That would be ingenious.

Would you be able to get low level access to the data lines on the usb interface to make it generate a square wave signal which looks like this:

-_-_-_-_-_-_-_-_

I believe the DDC signal was +5 and 0v, exactly what the USB provides

Hi Chris, so I've got a Sharp XR-10X on it's way, and I'm looking to get the delay dongle as well - now it's just the glasses. I was going to go with the NVidia 3D vision, until I saw the price - US$325 on ebay (that's nearly more than the projector [EDIT: RRP is actually $199, seems I just found some overpriced units]). So my question is, what is your recommended solution for the glasses, if I want to run on the latest video card hardware?

Can the NVidia 3D Vision drivers be used with competing brands of shutter glasses? Any comment on the quality versus say the edimensionals (I expect little difference based on what I've read).

I've read on another forum that the iz3d drivers work with shutter glasses (which support latest hardware/games) - should I just purchase these drivers and use something like the edimensional shutter glasses? This setup definitely works, I'm just not sure how it all ties in together with the delay dongle (which I figure is the component required to get the 85hz projector working cleanly with the iz3d drivers).

Cheers

You got the xr-10x cheap then, or was it without a lamp?

WRONG ThREAD..

I picked it up from ebay for US$380, mentions 80% bulb life remaining - though one with no bulb went for US$170.

You mentioned you're looking to get the 3d vision glasses (with this delay dongle), even though you already have the e-dimensionals. Have you tried the iz3d drivers - meaning do you definitely need the NVidia 3d vision package?

EDIT: further investigation shows NVidia 3d vision kit RRP is $199, the ones on ebay are just marked up - this price is a lot more palatable

Iz3d shutter mode only works properly if your framerate stays on or above the refreshrate. Since I want to actually use my gtx280 instead of the 7950GT, I need the newer nvidia drivers which will only work with the dongle from the 3dvision package. I already have mine on their way, for too much money, but I am not gonna wait for a european release which has been delayed from the previous rumour according to a new rumour

Also I should get my 2nd XR-10X tomorrow, now just have to find a 3rd. I was actually bidding on the bulbless one before, but I lost track of time before it ended so I lost :/

Apart from the 3rd XR-10X I'll need to get a triplehead2go. And then I need to actually get some proper screens.

Ontopic: James mailed me the manufacturing of the dongles is delayed because of the manufacturer of the PCB's easter timetable. No biggie for me as my rig won't be complete for a bit anyway

OK, So I finally got 3dvision working yesterday, by installing vista. Oddly enough it won't work on either of my computers on win7, eventhough it works fine for others. Today I got the delay dongle so here are my experiences so far.

First I tried it on my CRT monitor, because I hadn't setup my projector yet. The only thing it managed to do on my CRT is create a horizontal bar that I could move where the image above is parallax inverted to the one below the bar. Rather odd behaviour, not what I expected. So then I set up my XR-10X on a temp location just to test. Tried it in the nvidia logo test. On the projector it does seem to do what I expected, but it only seems to increase ghosting and mess up the colors when I move the dial any higher than completely counterclockwise. The parallax flip works as it should though, so the dongle is at least useful in making me not having to wear the 3dvision glasses upsidedown

@Xerion:
Did you use the VESA input of your 3dVision Controller? Sounds weird that when you increase the delay of the glasses the ghosting gets more?! Could you at least fix the ghosting problems with the dongle for your XR-10X at all

Jan

Xr-10x's ghost? Mine doesnt.