[David600]

I'm not kidding guys. I know Stewart does the TORUS stuff. i wonder what would be the cost.


It has to do with my BIG project for 2003: giant screen, JBL cinema speakers, QSC DCA rack, 30 seats.


So, Don (if I may ) if you log on, thanks for any price range on such screen and structure. The screen material will need some gain, around 2.0


check my yahoo home theater album
http://photos.yahoo.com/bc/huntforpr...heater&.view=t 5 (especially the last two, nice curved but not Torus screens )





David

 

[Vern Dias]

Perforated screens are not used for Torus designs, since the curve is obtained by applying a vacuum to the rear of the screen to make the screen shape conform to the proper curves.


Vern Dias

 

[CINERAMAX]

David:


For the third TIME!




The TORUS is a VACCUM SCREEN. One little hole and it will deflate like a spinnaker without air>


At the risk of being reprimanded for promoting something for it's righteous properties instead of greed...this is my TORUS website.

http://www.xtremedtv.com/torus.htm


Don does not have time for it so he let me handle the TORUS application devlopment. My clients both paid 27,000 $ for it in 1994. I believe I can produce these easily for 9 grand max.


Stewart woould supply all the propietary technology and licensing me and another forum member handle the wood part and final installation.


I just saw K-Pax at the Sunset Theaters down in South Miami.


It was well focussed so it looked awesome on the TORUS. The TORUS demands perfect focussing, otherwise it is wasted.


With perfect focussing however it blows away IIMAX on 35 mm. And aproximates reg 35 mm on HD.



Since I can make more money selling high end plasma systems, and prefer not to subject myself to the collective mood swings and menopausic school fish behaviour that the general members of this forum sometimes exhibit, I am a bit stand offish about pursuing the torus now . Probably in the summer i will continue.



I have the two finest CRT projection systems in the world installed here in Miami. Both Torusses


The better one has a JBL SYNTHESIS ONE mounted bellow the 11 foot wide screen


Come to the TRO PIC and experience the TOP PIC.


I am writing 48 hours before Hurricane Michelle hits Key Biscayne!!

 

[David600]

arf!! How ignorant i was! did not know the "vacuum=no perforation" issue


Peter: argh! I'll stick with plan A then, standard curved screen


But I sure do imagine it must look awesome on your systems.


cheers

David

 

[David600]

Peter: holly shxx !!!! just saw you torus site! awesome.


ok, let's see where I will be in 2003 and we'll talk again maybe

 

[Jeff Smith]

So how do comercial torus screens arrange their front speakers if they are not behind the screen? Its hard to believe they can get good imaging with speakers so far out to the sides.

 

[Vern Dias]

Either above or below the screen in the AMC Torus theaters that I have seen.


Vern

 

[CINERAMAX]

Are those where the speakers are also placed on the sides of the screen.


Both at Home and at the CINEMA.


When you place the three speakers DIRECTLY above or bellow the screen you will get cancellations in between the left and right channels that smear the stereo imaging.


If you place the left and right FLANKING the TORUS hang on for the ride of your life.


The Center channel above or bellow works quite well though unless you have reflections from the back wall which must be absorbed.


There are three types of AMC TORUS THEATERS, the Best is the Older Larger Squarish SDDS 2.35 theaters with a slight slant and the screen up 10 feet high. On sdds there are three speakers on top and two on the side. These theaters present the best compromise between picture quality and sound quality.


The smaller 1.85 rooms have the screen occupying most of the front wall, except with a piece on the side where the exit door is.


These rooms are my least favourite except for SHREK where the image was good. The worst flick in 1.85 was jurassic park three.

These 1.85 theaters have less powerfull lamp houses too.


The latest incarnation of TORUS is the Magnum 2.35 Stadium seating occupying the Entire front wall. Sadly, the final incarnation in Large Venue. There will not be any more new TORUSes in Movie theaters in the foreseeable future, probably ever.


This is the piece the ressistance for the VIDEOPHILE, that follows protocol. See PROTOCOL Bottom.



Case in point last night at the SUNSET 24 in Miami, K-Pax. A visual enjoyment like only the Torus can offer.


The sound? If the entire front wall is a concave structure obviously, you don't need a Russ Herchelman to tell you that there are going to be problems.


The anamorphic 2.35 really rocks on the TORUS


David, Mon Ami, To be perfectly blunt: A one way curved screen is a piece of crap, it creates a vertical hotspot in the center. It may sound good and look cool while you project ciclorama lights before the movie but it does not do didly squat for the actual picture quality.


An example of a great sounding Movie Theater with the TORUS is the Older large Squared rooms with 50 foot wide 2.35, high on the wall and 2 speakers flanking.

------------------------------------------------------------------------------------

PROTOCOL FOR WATCHING A TORUS MOVIE:


Call ahead and (LIE) inform the management that you are fed up with their projectors being out of focuss, that you are coming to see such a movie and that you expect it to be perfectly focussed.


If you cannot get a hold of the management by phone , make your request in PERSON.


Poorly focussed 35 mm projectors, benefit from the screen perforations of the CINEMA perfs screens to create a pseudo-sharpness. Somehow this phenomenom that I call NEGATIVE LIGHT MATRIX works well in the Brain. Not unlike the Fresnel lenticular Black Matrixes used in rear projection.



The TORUS screen does not have this negative llight matrix effect.


THE WORST ENEMY of the TORUS screen, the finest screen for front projection is TEREFORE: a slightly out of focuss lens.



Here is a link to amc theaters:

www.amctheaters.com


Find one near you and ask if they have the Torus. Only 550 of them do.


It certainly sounds like the one in SWEDEN does have it. With the very curvy sounding name like "Kungens Kurva". The one in Dunkerque sounds like an awesome theater but I see no reference to the curve. Good luck to those who call.


If you do follow the protocol, you will be pleasantly surprised.

 

[KBK]

I am going to be designing and publishing a cheap DIY toridial section hardscreen system soon., if it prooves to be too much of a PITA to manufacture and ship as a finished item.

 

[David600]

yo!


speaking of such large screen (6meter wide), and using 1.85 anamophic and 2.35 anamorphic lenses, are these foot Lamberts nrs correct and adequate for a nice home cinema viewing ?

I rule out CRT evidently and will stick to second hand 3DLP or 6segments DLP projector or 3LCD with high contrast ratio and adjustable blacks and Mila technology, with HTPC or Vigatec SDI source and making sure the image is in the middle of the optics to go with curved screens:


width: 6meters curved non Torus

areas:

2.35:1: 2.55meterx 6meter=15.31sq meters (165sq feet)

1.85:1: 3.24x6meter=19.45sq meters (209sq feet)

projector: typical 2000ANSI real ( more of 3DLP evidently)

screen gain: 1.8-2.0 microperforated

lenses: either ISCO or Prismasonic

estimated reflected brightness: 3500 ANSI ( = x +/-1.75 ?)

estimated Ft lamberts for 2.35 format: 21.21 FtL

estimated Ft lamberts for 1.85 format: 16.74 FtL


is this right ? As for the results, 15-20 fits the best SMPTE recommendations, right ?


Note: of course I know CRT is the best for life like realism but for such large screens, it has to be ruled out. I look for cinema-like images, not CRT like.

 

[KBK]

The lensing required for short throw, large screen toridial section... hmmm... I don't know if a sharp image can be obtained without the advantage of the 'outer focus ring' that CRT lenses have. If there is a single lens equivalent, well, only peter would know,as he has been looking at this for quite some time. Peter? Got an answer for the focus problem with large toridial screens, and single lens PJ's?

 

[CINERAMAX]

as a percentage of throw distance.


Torus screenscan vary between 70 and 94%. For Home 85%. At the Movies (INCLUDING CINEMA DLP) the radius is closer to 94%.

 

[KBK]

So, basically, what this means is that witha single lens PJ (digital type) you will have to go long throw to make sure your focus quality stays high enough to be acceptable. Short rooms need not apply. The CRT unit has the capacity to go short throw.

 

[Brett]

Darn it Ken,


Just when I had finally decided to go with a single curve along the vertical plane, you come up with this convex DIY project!





Hope it is something one can make on this side of the pond, ie not requiring fancy equipment only open to the aerospace industry or whatnot.


This thread is one I'll be spying with intensity!

 

[CINERAMAX]

I think I have made it very clear what a TORUS IS and what it is not.


The real genius of the TORUS is the custom Ray Traced curvature, and the reverse plenum design. That intellectual property belongued to GERALD NASH, who passed away on 10/29 of Brain and Lung Tumors.


This is a great loss to humanity, personally as serious a blow to Videophiles as it can come. He was the Cristopher Columbus of projection screens. Because front projection screens have to be Round and not FLAT.


I knew about his disease, that is what prompted me to create the webiste in hopes to beat cancer to the punch, maybe he could have seen the reality of the home TORUS project kicking?


So I am mad. Apparently the archetypal French bad manners have rubbed on real good, with our friend here.


I have asked repeatedly that the term TORUS be used correctly.


A solid toroidal screen is just that. And I wish KBK great success...


You know what Brett...?


I am fed up of your insinuendos that the TORUS is ellitist...


I am a videophile first, and seldom moved by material incentives.


your thriftiness has lowered you below any semblance of humanity in this case.


For the last time I request that you stop bellitling the memory of the GREATEST man in the history of projection television by misnorming the word TORUS ever again in this forum.



Don Stewart and I will carry on this TORUS thing, It will be as affordable as possible, but your negativity is most unwelcomed !!!

 

[KFung]

Ken,


The problem with short throw CRT's and toroidal screens is that you need a much larger curvature to direct the light to the audience. The advantage of a longer throw is increased focal depth and a shallower curvature. Ideally, you'd like to curve the screen less if possible to reduce geometric distortion.


I'm not to familiar with the focal range of CRT's, but I imagine that it could accomodate the curvature and correct for geometric distortions. A longer throw digital projector should not need these corrections, which is good because they don't have them! To paraphrase you, shorter throw digital projectors need not apply...


Both should work, but I would generally prefer a longer throw for the above reason of geometric distortion.


Regards,


Kam Fung

 

[CINERAMAX]

In fact you took the words right out of my mouth.


At first, the most necessary application for the TORUS seemed to me for obtaining larger brighter 9 inch crt's. A NECESSITY.


The real market opportunity exists in the 2.35 wide anamorphic projection of wxga panels. More OF A LUXURY, but quite an attractive one.

 

[KBK]

I am very sorry tohear of his death Peter. I had no Idea. I also stopped speaking of, and considering designs, as per ypur request. I will pursue agin, and publish results, and perhaps create something that can be used byall of us. Many will decide to go the pre-fab route, for sure.


At the very least, it will be a difficult undertaking, as a DIY project. But, I am fully convinced it can be easily done, with the right preperation and system in place, and the math of nature on your side.

 

[Brett]

Quote:

Originally posted by Brett Hope it is something one can make on this side of the pond, ie not requiring fancy equipment only open to the aerospace industry or whatnot.

Hi Peter,


Happy to hear from you - its been eons.


First off, sorry for unsuspectingly usurping dedicated terminology - a solid torroidal screen being just that and thus not a TORUS (tm).


I'm not much one for quoting myself, but upon re-reading my post I guess it was more ambiguous than I expected. What I meant was NOT that a manufactured commercial TORUS screen was something overly expensive or elitist, requiring high tech manufacturing open only to the most wealthy.


I only was refering to the limited availability of specialised tooling for rental here in France for do-it-yourselfers. For example, there are no projector lifts for rent here such as those Wm uses in the US. I can't locate a Wagner airless sprayer for rent to use with Ken's screengoo.


Therefore, there are some types of processes and tooling which are at the fingertips of DIYs in the USA which over here are only at the disposal of the specialized technical teams of large industrial groups. This was in no way a remark aimed at you or Don Stewart, nor your projects or dynamic involvement in furthering this noble cause destined to a deserved success.


A "true" TORUS screen, built by you as a justified hommage to your deplored friend and brilliant inventor Gerald Nash, is most likely a much more sensible purchase (in terms of value for the dollar spent) than many others that we Home Theater enthusiasts sometimes make. Its projected pricing is quite cheap when compared to the high-end projectors or to the top video processors, and it definitely is in their league. So I'd be the last one to knock it.


Then you've got the logistics of it: I'm a the top of a building with very limited staircase access - no way to get an RPTV up here. So being able to assemble a screen on location from parts is a major consideration. Notwithstanding the numerous problems I've had in shipping things from the overseas: projector dropped from a forklift, LD players with bent internal parts from shocks, etc. not to mention the lovely folks down at customs who get a kick of charging up to over 40% duty. So this rules out importing big ticket items.


As with many DIY types, there are a couple motivations at play. One is finding a way of reaching a goal that you couldn't otherwise achieve. Anyways, if you ever need a beta tester over in these waters, look no further, I'm your man!


Cheers,

 

[CINERAMAX]

Dear Brett:


Sorry to take Gerald's death out on you with such DRAMA.


I want you to think of something regarding this beta test with wish perhaps I could come and assist myself. If I sell plenty of plasmas this x'mas.


The Torus screen is particularly easy to implement in European Flats, because it is assembled on site. If you can get a Christmas tree up your stairs you are in business, then.


Although "officially" this is speculation, Imagine that you could purchase from an outfit like AVSCIENCE a Torus kit.


The Kit would include a Meticulously packed Stewart screen.

A set of electronics. not larger than a briefcase. A set of plastic parts about the size of a golf Bag. And detailed instructions.


Where in America the kit would include the screen frame made out of wood or Corian (very expensive); Since you are in Europe you would supply your own carpenter to build the frame.


The Screen assembly would take one to two days.


The 1292 is ideally suited for a TORUS SCREEN, somewhere in the CRT forum Chris Williams explained that the lenses on the 1292 are optimum for a curved screen.


But in order to have maximum success you really have to think 3-d and supply us all the details of the viewing environ. To have the light serve the audience.


For example I think that the more practical sizes for the TORUS Screens start at 9 feet wide 16 by 9. In Europe your needs could be less. Please refer to the first TORUS table in the website for light output figures.


We need to know how high the projector is mounted. What the seating area etc. etc.


So think about these issues, and set aside the cost for a moment, there are 5 of us, whom you all know, working hard to make Gerald's Legacy, a reality for the Home.


As for the timing, Sometime after the American launch , your Beta site will make sense.


Regards


Peter