Stage Video Relay Link
Providing a visual link for stage use can be used from theatre for musicians to time to a conductor, through to a corporate awards where the guests in the green room needs to see the stage to see what is happening. Any situation requiring a visual relay needs to be simple, be seen and most importantly of all with minimal delay.
Modern HD video systems provide great crisp images however they have one flaw, they all take too long to process the information and cause delays of up to 500 microseconds ( half a second). This kind of delay causes issues with singers and bands. Old CRT TV screens were great as the systems are analogue there is virtually no processing causing minimal delays. The only problem is that old CRT monitors are becoming hard to get, and hanging a larger than 21″ screen proves tricky due to its size and weight.
We keep to a simple system using traditional CCTV analogue cameras and distributing the video signals over analogue VGA cable and composite coax cable with the images being viewed on fast refresh rate LCD monitors ranging in size from 19″ up to 50″. Our monitors can be supplied with either freestanding floor stands, or angle brackets which fix to standard scaffold bars.
It’s often useful for members of the cast of a musical or stage production to be able to see the conductor to keep timing and provide a closed loop system.
Another view is from the conductor who may be in the pit, off to one side of the stage or even in a back room to be able to see the whole stage from the audience point of view. A cue starts when the principal character walks upstage left, the cue needs to fit perfectly to when they walk out of view.
50″ Relay monitor Freestanding floor stand
21″ Bar Mounted Relay Front of House
Cameras and options
Our simple cameras are usually fixed focus and can either be hung on a lighting scaffold bar, or screw onto a microphone stand and are easily adjustable to get the best image. We can provide IR illumination which will turn the cameras black and white but will enable you to see perfectly clear on a blacked out stage or orchestra pit. Infrared illumination is a popular choice for stage managers to see the stage to make sure set has been struck or to ensure all cast are in place before running lighting cues to start.
Is there a problem with delay?
With HDMI and digital signal processing there is always an element of delay. In the old days of theatre relay screens would have been analogue CRT monitors which provide virtually no, but still some delay. The only downside is that a 27″ screen took at least 2 people to move, and was physically very big. We use LCD digital monitors however still run the majority of signal processing in analogue. Sure this has an effect up close on the screens where the image may not be HD crisp, but from 5-8m it’s perfectly fine, and the trade off of image v’s the minimal delay in our eyes is well worth it and has never caused a problem. Even for the most critically timed MD. Take a look at the video to the right to give you an example of the delay, which is about the same time for a DSM to recognise a cue then issue a go command.
