added 28 March 2007

 

Using Video On The Stage
an article by Boyd Ostroff

In my job as Director of Design and Technology at the Opera Company of Philadelphia I've been fortunate enough to have the opportunity to explore the use of digital video on large screens in several of our productions. Each production has been a learning experience featuring both good and bad lessons along the way. In the following article I will share some of these experiences as they relate the choice of screens, projectors and media servers. While small scale projects can be mounted with inexpensive off-the-shelf consumer equipment, putting together a big production on a large stage with expensive union crews is another matter. If you ever find yourself in such a situation then perhaps some of my experiences will help point you in the right direction.

Projection Surfaces
One of the first considerations when using video on the stage is the surface you will project on. For productions of Il Trovatore and Die Walküre we used large (approximately 50’ wide x 26’ high) white sharkstooth scrims at the front of the stage with projectors located in the rear of the audience. Scrim is a seamless woven fabric which is often used to create the theatrical version of a crossfade or dissolve effect. When lit from the front it appears solid, but when lit from behind it becomes transparent due to the open spaces between the individual strands. This allowed us to dissolve between a projection at the front of the stage and live action behind the scrim. See this link for more information and pricing on scrims.

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Il Trovatore  ·  Opera Company of Philadelphia  ·  Director: Kay Walker Castaldo  ·  Scenery, Lighting and Projection Design: Boyd Ostroff

Another commonly used technique is rear projection. For a full stage projection about 40 feet wide we use a backdrop made of Rosco Grey RP screen material. The large screen is custom made to your specifications by “welding” multiple horizontal strips of 55” wide vinyl. The top of the screen is tied to a fly system pipe in the theatre and the bottom of the screen is constructed with a “pocket” to accept a long pipe as weight to stretch the screen.

For smaller screens we have built steel frames of welded 1”x2” rectangular steel covered with wood strips. The screens fabric is custom made to our specifications and we attach it to the frame by stapling to the wood strips. If your screen is small you can purchase rolls and cut pieces of either 55” or 110” wide material and eliminate the wait involved with a custom fabrication job.

See this link for more information about a are a variety of other screen coverings in addition to the grey material. And aside from traditional screen surfaces, remember you can also project on walls, floors and people!

Projectors
The most expensive component of the system will likely be the projectors themselves. It is hard to give a “rule of thumb” regarding the correct size projector for different applications. But my experience has been that you will want a 10,000 lumen unit if you want to cover a front projection surface in the 40 to 50 foot wide range. Ideally you might want a little more for a rear screen; we used 10,000 lumen LCD projectors for a 40 foot wide rear screen and were pretty happy with the results in a dimly lit opera. But to achieve an image that size from the rear in a more brightly lit scene I’d like something a little more powerful. For our production of Cinderella we were happy with a 5,000 lumen LCD projector on a 16 foot wide grey rear screen on a brightly lit stage. In Die Walküre we thought a 5,000 lumen LCD projector was fine on a 26 foot wide rear screen in dimly lit conditions. As they say, “your mileage may vary” so try to audition a projector in your own theatre if budget and time permit.

For Il Trovatore we used two Barco SLM-R10 10,000 lumen DLP projectors located in a balcony booth approximately 100 feet from the front of the stage. Although only one projector was needed, everything was duplicated in order to be redundant (which, in retrospect, was a rather expensive form of insurance). See this link for more information.

These projectors had an internal shutter to completely blank the output when not in use. This can be a serious issue worthy of consideration when planning projections on the stage. Even if you send pure black to a projector, it still emits some light. This varies with the technology – DLP projectors typically have blacker blacks while some (especially older/cheaper) LCD projectors don’t go any darker than a medium shade of gray. If the projections are used on a brightly lit stage then this might not be a problem. But if light levels are low, and if you want a true “blackout” then you will probably need some way to physically block the light from the projector.

If your unit doesn’t an internal shutter for then there are external “dowsers” which can be used, either under manual control or programmed by cues on a lighting board. For an example see: www.citytheatrical.com/la-dmxIris.htm#projector. Or, if the projector is easily accessible, you could just have a crew member put a piece of cardboard in front of it while not in use.

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House Electrician Tim Johnson next to two large Lightning 15-sx 10,000 lumen DLP units from Digital Projection in the close quarters of our lighting booth. This photo was taken during a feasibility study on the use of video projection back in January 2003. Newer units are smaller, lighter, less expensive and produce a better image than these old workhorses which weighed in at over 200 lbs each!

For recent productions we haven’t been able to justify the higher cost of DLP projectors and have turned to less expensive LED units. For Wagner’s Die Walküre at Teatro Colon in Buenos Aires, Argentina we used two Sanyo PLC XF45 10,000 lumen LCD projectors. One of these projected on a large front scrim while second projector was mounted on a truss at the back of the stage to cover a rear projection screen.

An interesting feature of these units is their design which includes 4 separate lamps which can be used in several combinations to provide different levels of output. We actually dialed the rear projector down to run on two lamps as we felt it was overpowering on the smaller screen in dark scenes, But the multiple lamps also provide redundancy in the case of a burnout; the projectors will continue to run at reduced intensity which is a great feature for stage use and provides a level of backup without the need to duplicate equipment (see this link for more details).

This same unit is also marketed under different brand names; we used the virtually identical 10,000 lumen Christie LX-100 “Road Runner” LCD projector for A Masked Ball –- see this link for more details.

For Cinderella we used three 5,000 lumen Sanyo PLC XF30 LCD projectors on different sized rear screens. These units are similar, smaller versions of the XF45 projector described above and also have the advantage of multiple lamps. For more information see this link.

While these 4:3 native 1024x768 LCD projectors aren’t as nice as the Barco DLP units, they represent a lot of “bang for the buck” and are widely used workhorses in the theatre.

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Cinderella  ·  Opera Company of Philadelphia  ·  Director: Davide Livermore  ·  Scenery Design: Santi Centineo Projection Design: Marco Fantozzi  ·  Lighting Design: Drew Billiau

Video Servers
You will also need a way to send video to the projector, and there are a lot of options here. The simplest would be connecting the projector to either a tape deck or DVD recorder. For a very simple production this might work, but experience has shown that neither of these systems hold up very well in demanding applications with lots of video cues. Another simple option would be playing the video directly from your NLE timeline on computer. This works, but is also awkward for complex shows. VJ software is yet another option that may be worth considering, although I haven’t personally tried this approach.

For complicated shows it makes things much easier to use a system specifically designed to present video in a theatrical environment. We’ve been using Catalyst Pro media servers from High End Systems recently and are really pleased with the amount of control and flexibility they offer.

Each server consists of custom interface hardware and software running under MacOS X on a dual G5 Power Macintosh. Depending on the format of your video content, media is stored on either internal SATA drives, external firewire drives or a disk array. Each server can drive a maximum of two screens.

The server software has a rudimentary user interface, but is not really designed for direct interaction with an operator. Instead, the server “speaks” the same “language” used by theatrical lighting consoles – the DMX-512 protocol. The Catalyst hardware includes a DMX-512 module which can either plug directly into a lighting console or a lighting network in the theatre. Once everything is properly configured, your projections can be treated as another element of stage lighting cues and controlled from the same console. The programming interface is very similar to that of moving light fixtures such as Vari-Lites.

Each screen connected to the server can have video loaded onto multiple layers which behave similar to layers in Photoshop. By controlling the opacity of the layers you can achieve dissolve and transparency effects between multiple clips. The clip speed, duration, size, in and out points are also among the attributes which can be varied on each layer, and all of these are accomplished in realtime by the server’s graphics cards. Multiple servers can be controlled from a single console and locked into sync if needed.

While it takes some study and planning to setup and program a system like this, the possibilities are endless. And the payoff is that everything is controlled by a central console using stored cues, so each performance will be consistent and repeatable.

For A Masked Ball we used a single Catalyst Pro server to drive both a front and rear projector. The server was controlled by the same console which ran the stage lighting which insured that light and video cues would always be in sync.

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A Masked Ball  ·  Opera Company of Philadelphia  ·   Director: Robert B. Driver  ·  Scenery and Projection Design: Boyd Ostroff  ·  Lighting Design: Drew Billiau

For Cinderella which had more complex video needs we opted to use a separate console to control 3 Catalyst Pro servers each of which drove a rear projector. We chose the Wholehog 3 console, also from High End Systems because of its user friendliness and integration with the Catalyst system. All of the server’s features are mapped to touchscreen functions on the “hog” which simplifies programming.

Another important thing to consider is how you’ll get the video signal from the server to your projector which may be a hundred feet away. For this we’ve been using a system which allows us to send the VGA or DVI output of the server’s graphics card to the projector over standard ethernet cable. Extron is one of several companies which make this kind of product.

Systems like this are getting a lot of use in theatrical productions and live concerts these days, and while they still aren’t cheap, rental prices are falling and most moderate sized theatrical rental houses will have them.

What Will it Cost?
Each year brings lower equipment costs, and we’re seeing a lot more capability for the dollar with each season. For example, renting two Barco 10,000 lumen DLP projectors and two Doremi hard-disk recorders for a month cost about $50,000 for our Il Trovatore in 2003. Our 2005 production of A Masked Ball consisted of two 10,000 lumen Sanyo LCD projectors and two Catalyst Pro servers. A one month rental came in around $36,000. For Cinderella in 2006 we had three 5,000 lumen LCD projectors, three Catalyst Pro servers and a Wholehog console for a month at a rental cost of about $20,000.

In the case of Cinderella we were able to work within the inventory of some Philadelphia area rental houses and get more favorable pricing than the previous examples which were provided by a New York City supplier. So as you plan a production a good first step would be a visit to local A/V rental houses in your area. If you can work within their limitations you can probably save some money. And it’s also nice to have a local company to turn to when something goes wrong!

Written by Boyd Ostroff.
Thrown together by Chris Hurd.

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