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Topic: Light Valve Projection???

Dave Bird
Jedi Master Film Handler

Posts: 777
From: Perth, Ontario, Canada
Registered: Jun 2000

posted 01-27-2001 10:11 PM

Check this out from the drive-in discussion list: We've all heard of the drive-ins that a re-opening, even some new builds that expand to multiple screens. But Barry with his twin going up in Tennessee and these folks below (near Baltimore) are building a couple drive-ins with the "multiple activities" and scope we used to see. Anyway, to my question, what exactly is this
"Light Valve Projection"? Another curiosity is why identical size screens for 500 & 150 cars, but hey, God love 'em, supposed to open July of this year.......

>>>We are building 3 screens, one at 500 cars, one at 350, and a small one at 150 cars, total 1,000 cars. We are using 35mm projectors and 16mm at all three screens. We will book most current movies as well as oldies.

At times we will be using new technology called Light Valve Projection, This projector is a full blown High Definition component video projector. We will be showing DSS, DVD, SVHS, and many other forms of video. Our screens will be 65 feet wide and 32.5 feet tall true cinemascope wide screen formats. Letterbox will also be used.

Sound will be wireless AM and FM as well as Dolby Surround Sound at our outdoor seating areas! Our concessions building will house our restrooms and arcade, approx 3,000 sq. feet total. We are building volleyball courts, horseshoe pits, two playgrounds, a few tetherball courts, picnic tables, and a covered patio. Our GOAL is to promote family-oriented entertainment!! For ALL AGES!!! Hope to see you at "Bumpers Drive-in Theater"<<<

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Scott Norwood
Film God

Posts: 8146
From: Boston, MA. USA (1774.21 miles northeast of Dallas)
Registered: Jun 99

posted 01-27-2001 10:24 PM

Light-valve projection isn't a new thing, though this particular implementation might be. It's basically a really, really big CRT. The original poster is probably referring to the Hughes-JVC ILA projector, which is a technology which is somewhat competitive with DLP for high-end video display on large screens.

Note that the video sources mentioned aren't at all acceptible for large-screen presentations. DSS and DVD have nasty compression artifacts, while SVHS is relatively low resolution (16mm is many times better). Betacam SP or 1" tape is probably the lowest you can go for largeish screens, and there are many expensive formats which are better. The best video formats in common use are still inferior to 16mm film, however (which, with DTS, can provide full 5.1 sound!).

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Josh Jones
Redhat

Posts: 1207
From: Plano, TX
Registered: Apr 2000

posted 01-27-2001 10:58 PM

Lightvalve Projection was used in large auditorium projectors in the 60's 70's
does anyone know how those babies worked?
If I can find a picture, I'll post it

Josh

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 01-28-2001 12:19 AM

Actually light valves do not use a direct projection phosphored type CRT. They utilize a special CRT in which a conductive oil film is continually circulated. This oil film is scanned by an electron beam to form an image and then relayed through dichroic mirrors to the projection lens. These projectors are very very complex and expensive to buy and maintain. They utilize a standard Xenon lamp for a light source. They are capable of ok looking 30'pictures. General Electric made allot of them both in Color and Black and White models. There was also the Ediphor projector from Switzerland which was similar but as far as I know was never sold but only rented. All of these have a built in vacuum pump to maintain the vacuum inside the projection tube which opens for servicing and maintainance. I have a friend that had a number of them in his rental inventory and he said they were a pain in the ass to deal with. He switched to the Hughes projectors and now to DLP.
Mark @ GTS

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Josh Jones
Redhat

Posts: 1207
From: Plano, TX
Registered: Apr 2000

posted 01-28-2001 01:13 PM

does anyone have a picture of it's innards?

J.K.

Josh

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Ian Price
Phenomenal Film Handler

Posts: 1714
From: Denver, CO
Registered: Jun 99

posted 01-28-2001 02:18 PM

It looks like DLP has killed the Hughes/JVC light valve. All of my old links to Hughes/JVC are dead and there is a note somewhere that JVC America has taken over that business.

We had a Hughes/JVC 320 at the United Artists Greenwood Plaza to use with their Proteus Network (Now called the Satellite Theatre Network.) Think large-scale video teleconferencing for rent. It was a great machine but it was difficult to fully set up properly. Now that I have played with the Digital Projection series of DLP "motion data projectors" I would never like to deal with a Hughes/JVC light valve again. The Digital Projection systems are plug and play.

You could make an argument that the Hughes/JVC looked better with video if you had it set up correctly and had a $20,000 Faruja line quadrupler attached. But the Digital Projection system doesn't need the Faruja system and makes computer graphics look great. The video doesn't suck either. The only thing that sucks is the price. Video projectors should cost less than luxury automobiles. When they cost like economy cars, more people and theatres will buy them. But so far the only way to make a profit with a large venue video projector is to rent it to other people for image magnification at conventions. I don't think any body has made a profit from a video projector in a fixed venue location, unless that venue is for rent.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 01-29-2001 07:46 AM

Here is a link to information on how "light valve" projectors like the Eidophor and GE Telaria work:
http://www.iao.com/howthing/eidophtm.htm

AFAIK, these are very complex devices that require quite a bit of "tweeking" and maintenance.

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

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Barry Floyd
Phenomenal Film Handler

Posts: 1079
From: Lebanon, Tennessee, USA
Registered: Mar 2000

posted 01-29-2001 07:46 AM

I too was curious about this "Light Valve Projection" system when I read about it over the weekend.

"If" they build everything they say they are going to, more power to them. My pockets aren't nearly that deep. With 35mm, 16mm & digital on each screen..... they either won the lottery, or the prize patrol showed up after the Superbowl last night. How can they plan on recouping the cost of such a facility? I'm doing well to figure out how we're going to make a profit with a twin running 35mm only.

Like someone said earlier on the drive-in discussion list.... it does almost sound like a health spa as opposed to a drive-in.

------------------
Barry Floyd
Floyd Entertainment Group
Nashville, Tennessee
(Drive-In Theatre - Start-Up)

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Ken Layton
Phenomenal Film Handler

Posts: 1452
From: Olympia, Wash. USA
Registered: Sep 1999

posted 01-29-2001 07:58 AM

Barry:

You're right. How can they make this theater profitable. The base costs are so much that it would take a long time to pay for everything. What happens when all those "gimmicks" wear off?

How is that expensive video projector going to stand up in the dusty environment of a drive in? It even uses MORE electricity than the 35mm projector!

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Dave Bird
Jedi Master Film Handler

Posts: 777
From: Perth, Ontario, Canada
Registered: Jun 2000

posted 01-29-2001 02:27 PM

I fall into the same "how are they financing this" camp. I just asked them a couple more questions on that list. They claim these things are "well under $100K." I wonder who makes the model they're buying.

Sure, more power to 'em. Imagine all the cool stuff you could bring back, all the "lost" intermission films, cartoons. But after the novelty is gone, I still think people want good movies in the comfort of their own cars, a playground for the kiddies, and good food.

You have to say that film (done right) is still state of the art for the "trifecta" of RELIABILITY, cost, and security (piracy) issues. We'll see what they say......

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Pat Moore
Master Film Handler

Posts: 363

Registered: Mar 2000

posted 01-29-2001 02:41 PM

I would think a big issue here would have to be the use of DVD's, etc., to project for a paying audience. Isn't that regarded as illegal? Certainly a bad plan if they plan to rent film in a normal manner.

Pat

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Ken Layton
Phenomenal Film Handler

Posts: 1452
From: Olympia, Wash. USA
Registered: Sep 1999

posted 01-29-2001 04:18 PM

What happens when the thing craps out on a busy Friday or Saturday night? How much will it cost to repair? How's availability of parts and/or a qualified serviceman?

What happens when there's a power surge, brownout, or electrical storm?

On the copyright issue, go ahead and run a Disney video and see what happens! You'll be either in the poorhouse, courthouse, jailhouse, or all of the above.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 01-29-2001 04:24 PM

You'd better know the technician in your area!! As far as the GE units go that division of GE was bought out by a number of its employees when GE shut down the division. I don't know if they still run it but I would think they would. There are more GE Light Valves in the world than any other type. It is extremely expensive torepair almost any aspect of them.
Mark @ GTS

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