Meant to be Seen

Many thanks for the reply

Again excellent information I am getting from you guys as always.

One thing that I need to take into account, how much would such a setup cost me?

Is it okay to use two 1024x768 monitors? That would give a combined resolution of 2056 x 1536

another question, I have a sanyo PLV-Z2 LCD native 60hz 1280x720p projector. It can also do a resolution of 1280x1024 85hz, is it possible to get another one of these and do circular polarized passive projection or even just use the one to do active projection?

Many thanks in advance

Lcd's and active solutions haven't gone together well but this has changed lately! The only way to be sure is either ask someone with experience of active with the specific projector you have. If it handles 85 hz it means that it takes 85 hz as input. NOT that the screen itself necessarily refreshes 85 times a second! If you have shutters you can try, the only other way is to ask someone with experience of the specific projectors. Generarly i have the impression that dlp-projectors have higher compability with active shutter designs than lcd's.

What 3d-projectorsetup to choose depends on how much money you wants to spend.
For an active solution you need a compatible projector and shutterglasses. This is the cheapest and probably a more ghostingfree solution (depends on the hardware used though) than a passive setup. You'll loose quite some light so you need a dark room. A pair of shutters is needed for each viewing person. A maximum of light throughput is 23% to each eye because the shutterglasses only let through 45% light max when "open". Reason why shutters do this is simply that they're using polarization (45% loss) to shut on/off. Since the eyes has to share the total light the total result is only 23% each eye.

A passive solution is expensive because: You need two projectors, silverscreen and projectorsfilters. One simple pair of polarized glasses is needed for each viewing person.
According to my experience you can use simple polarized filters with the angles 45/135° with lcd'projectors (tried with mine) with good results. If the projectors have 45/135° native angles for the colors this don't work. Then you have to use 0/90° glasses and filters.
You'll loose some light (45% max light throughput each projector) but since you have two projectors you'll have double as much light as with shutterglasses.
If you use special stereopol filters (only works with lcd's) you'll get a very high light throughput: 75% and greater to EACH eye! I have them and gaming on 100" with 2000 lumen projectors in fully daylight is no problem.
If you ask me ghosting is no problem in a passive polarization rig and you can also check the picture in the link above.
Tip: If you're going to use ordinary polarizers from polarization.com or whatever: Keep them at a few cm's distance from the beamerlense since i fried a pair of cameralenses trying. I had them very close to the lense at this time though (5 mm's )
Be sure you have keystone correction on the projectors! Otherwise you'll have to live with a scewed 2d-vision with your screen. It still works ok in 3d though. It's also a slight bit tricky to align and trim the projectors right in a passive rig but that's a part of the sport.

Sidenote: I think you can try out how your projector works with a curved screen if you take some white bed sheets and hang them on a curved structure (metalbar or whatever you have in your possesion). Then you should be able to try how your projector optically behaves with such rig.

Cheers!

Many thanks for the replies

I will have to do that white sheet method to see the sort of curve I can get from my projector, could you tell me please can you use shutter glasses to do active stereo on two LCD projectors, or with two is it always only polarized 3d?

sorry for all the questions

If my LCD projector turns out to be able to see stereo 3d, then I was thinking of buying the Nvidia sutter glasses when they are released, do you know if they would work with their new drivers on on LCD projectors? From articles I have read there is no mention of projectors, only LCD and DLP monitors, they say you need true 120hz monitors, it sounds like it's not absolutely needed only if you just want the best effect, can you verify as well if it's okay with a projector that's capable only of 85hz?

One other thing, I just read of sanyo coming out soon with a true 120hz refresh rate LCD 1080p projector, it's going to cost $3350 that's pretty incredible as I could use them with Nvidia's new solution for active stereo, I may have to hold off from doing the full curved screen setup as it seems to be quite costly, so I could instead work on building up to it, start with one projector and a flat screen and then after as I got more money work towards getting 2 projectors the curved screen, the custom made metal projector framing etc

Lastly I just read on this forum that when you do two projector setups you don't double the refresh rate, it was my understanding that if you use a single projector that has true 120hz refresh rates then each eye sees 60hz if you use two 60hz LCD or DLP projectors you then get 120hz (which is the same as 60hz for each eye, simply one projector for each eye, each projector being 60hz or 85hz)

Sorry for all the questions but I do hope you can answer them

Many many thanks in advance

No problem. I'll answer those i can but now it's starting to be difficult. Not because of the questions, rather that i don't know the answers.

I'm not sure if get it right with using two projectors in an ACTIVE config. The only way i can think of it is using them in span-mode so you get a very wide screen which should be possible, even in 3d using shutterglasses. I have no practical experience in a setup like this though but i think i've seen such a setup in a thread somewhere. Of course both projectors need to handle active 3d for this to happen.

Regarding the new nvidiadrivers i don't think anybody else than nvidia know refreshratelimitations or anything else with their new drivers. It would be strange though if other refreshrates than 120 Hz can not be used but it's an open question so far.

I don't know any ways to see how a projector manage active 3d with shutterglasses without having shutterglasses themselves so i can't really give an answer here. But: These are lcd-projectors and they're most probably not able to handle active 3d.

And yes: It's true that two projectors does not increase the refreshrate in stereo. The shutterglasses works the way that they cut off one eye when the image for the other eye is shown and vice versa. This means that if you're using two projectors they still have to shift images at the refreshrate to work properly. This is also why i cannot see any other practical solution than spanmodes for multiple projectorsolutions with shutterglasses. Having two projectors beaming at the same area on the same screen will increase the light, not the refreshrate.

Many thanks again for your reply sorry that I was late to respond. I think I am going to have to sit down and do some extensive research and a lot of reading before I go spending any money. I will need to find just the right setup and see what I can do on a budget. But anyway thank you very much for all the replies you guys have all being very helpful.

Hello. Im in the prosess of putting up my 3d rig. Ive used this great guide as help. I use a harkness 3d screen. My problem is that it is much brighter in the center than in the edges. Is there a way around this? projectors further away, or sitting further away? the last one seems til help a bit.

edit; I used tips recived from Yahun, and now it works great

I also have that phenomena but strangely enough i only noticed it after i took a picture on it and looked at the picture.
I believe it depends highly on the screen used though. Myself i use a silverfabric screen and i don't feel a need to try anything else.

I have now put up my own 3d projection rig using your great guide. And the result exeeds all my expectations.
I bought a harkness hall spectral 3d silver screen. It only costed 158 euros, including boarders and eyelets!
roughly 2,1 * 1,2 meter. thats not twice the price of the silver fabric.
the price for the exact same size and features from silverfabric was 497 euros (also including straps).
Felt the need to correct the pricing information. I recommend harkness 3d screen. Both for price and for 3d quality.
Thanks for a great guide

Thanks! I sooner or later will replace mine since i have some wrinkles on it won't go away (mishap first time when too eager to set it up ). How is the harkness in characteristics? The silverscren is like a textilebase with a thick silvercolored plastic coating. It's elastic which is ok to use with my rollercurtain. You think a harkness will do as well?
I've mailing them now and see if i might get a sample from them.
Thanks for the tip btw. I'll let you know what it's gonna be.

I have no experience with other silver screens, but I think it is great. Nearly no ghosting. I even use it for linking (2 xbox 360 linked together, using only one screen, with modified glases that have the same polarization) There is some sparkling to be noticed, but only on even coloured areas as mentioned.
It looks like a reguler strechy material with some sort of spray paint on. I think it has to be streched to a frame to work the way it is ment. Then you get no wrinkles. The viewing angle and polarization ratio is also great btw. peak polarization is 140:1, and viewing angle is 24 degrees off center. (i think silverfabric is 80:1 and 17 degrees). Looking forward to hearing of your findings with the sample.

how much did the op spend on this passive setup?

epsen83 wrote:I have now put up my own 3d projection rig using your great guide. And the result exeeds all my expectations.
I bought a harkness hall spectral 3d silver screen. It only costed 158 euros, including boarders and eyelets!
roughly 2,1 * 1,2 meter. thats not twice the price of the silver fabric.
the price for the exact same size and features from silverfabric was 497 euros (also including straps).
Felt the need to correct the pricing information. I recommend harkness 3d screen. Both for price and for 3d quality.
Thanks for a great guide

Thanks for the info, not sure why it mismatches yours.. My original info in the first post is getting a bit old but that's a huge difference. Perhaps transport costs were high, or I just had a very pricey reseller But that 158 euros is very cheap, nice!

Perhaps by now there are so many sellers, and buyers, that prices are getting more sensible. In the end, it's not superspecial material and has existed for a while.

smoothy wrote:how much did the op spend on this passive setup?

Hmm didn't I write that down up there?
I guess 2x 1.2k for the projectors was by far the priciest part. Guess some 500-1000 extra euros for screen, filters and a pretty good aluminium frame... So 3.5k tops?

Projectors are cheaper now and the screen can be stretched onto a board (is better too, I just needed easy mobility) and with a 158 euro screen price mentioned here I guess it can be done verywell for <<2k euro's now.

Hi to all I'm new but very interested....
I read the forum, reply and posts but I'm still confused probably because my english isn't perfect..
A question: I have an hitachi pjtx300 and soon another one (tx100 or tx 200 or tx300), can you explain me exactly what I must have/buy and where? and how to assemble all?
Sorry for my bad english and thanks to all!!
great site!!!!

Hi
has anyone tried Screen-Tech screens?
http://www.screen-tech.de/" onclick="window.open(this.href);return false;
they have front and back projection passive screens
The rear projection ones look interesting because they are rigid and can be ordered with frames
and not too expensive for the smaller sizes. I am thinking of converting a rear projection television
chassis to passive back projection

Peter m

Umm , where one buys harkness screen for 158 euros...

Huh ??? that rigid front projection screen from screentech seems very interesting.
I was about to order from Harkness but suddently I have like a small doubt.

Edit : the price list is for small screen size, unroll the screen size list far on the right on the order page, the prices explode with bigger screen sizes.... sad I was about to be convinced.

I ordered one of the Screen-Tech back projection passive screens I mentioned and it came promptly (to Australia) from Germany
and it works ok. About $650 US including shipping to Australia for a 1.3m wide screen
It is a thin rigid gray plastic material like a Stewart back projection screen. Unfortunately it was damaged in
transit (inadequate packaging and lousy handling) so it has a hole in it -- so they get no points for packaging and choice of a courier -- but the actual
screen has good extinction. And the level of hotspotting is ok. I chose the framed version -- brushed black aluminium and that is very nice.
The projected image is not terrifically sharp (though I chose the thinnest of the materials) but I think
that might be how these things are -- maybe the 3d Virtual Black
http://www.berezin.com/shop/1603" onclick="window.open(this.href);return false;
which I understand to be a thin foil -- might be sharper.

Peter M

Have any of you guys here tried other methods of passive 3D like Dolby? or the Omega 3D filter system ? it dose not need a silver screen.

http://www.youtube.com/watch?v=RiWf_69x ... ure=relmfu

Anyone tried the (new) solution from Omega Optical (Depth Defining 3D)?
Seems to have many advantages and is quite cheap, but maybe it would be too good to be true ...
I would be delighted if somebody could share its experience with this system.

Hello all,

I'm intending to upgrade to the Omega Optical (Depth Defining 3D) system, and that means that my awesome Harkness Hall screen will soon be possibly up for sale.

Is there a market for second-hand silver screens that are in great condition?

here is a new offering as a package with the omega 3d system kits. the geobox 501 dual projector demultiplexor with curved screen warping, edge masking, geometry correction and will do 60 FPS at 1080p from a pc,

http://www.youtube.com/watch?v=o0OWvLBOYZM

Cool.

Hey motorman... how much is the demultiplexor?

Sorry this took so long but i can now sell the demultiplexer as a kit with the omega 3D filter set and 12 pairs of glasses. ive been playing with an Xbox 360 with kinnect and my 3D passive dual projector rig. one question i get is alignment of hte projectors. so i made a video of the demux box alignment tool on a 12' white matt screen and i played some 3D games on it with the Kinnect. pretty fun really.

http://www.youtube.com/watch?v=yLqkZ45AW-c

the same rig works great with a PC and a single DVI output as long as you can have the game put out SBS or some format of 3D, the Geobox will auto select the right setting for putting out the two images to the projectors.
the demo is on a 12' screen and im no more than 8-10 feet away using the kinnect.. i need COD black ops now lol.

oh and for the cost ?? well there is a link under the video of what we can offer the set for

Hey motorman! I would like to test your system Omega DD3D! I intend to purchase of 2 large filters and 9-10 pairs of glasses for my 3D rig with 2 LCD projector Panasonic PT-AE 3000E. This system is still in production or you planning to produce a new (improved ) version perhaps? It is possible to find system somewhere in Europe (I'm from Romania) and how much it cost? Thank you.

Hi. we sell the filter system on ebay.

http://www.ebay.com/itm/Depth-Defining- ... 0386486843

this one has the larger projector filters you just need to tell the ebay seller you want LCD filters. and it comes with 10 pairs of glasses.
there is no new generation as i spent several years perfecting this system for cinema and it is refined as it can get.
ask me any questions you may have and i can help.