Ethernet and Projectors for HS Theatre

[Luke_R]

Hi all!
I am currently involved in trying to figure out our projections for our fall play. Due to the length from our operator to the positions on stage, HDMI and other connections are unfeasible. Given our recent experience with livestreaming and NDI video, my TD and I have tried the native LAN connection on the back of the projectors but cannot get it to display anything more than a mirrored desktop, if that. My question is: without dropping a lot of money on converters or specialty computers, is there any way to use more than one projector from the same computer with ethernet cables?
My apologies if this has been covered elsewhere, but I haven't seen anything yet.
Also, inexpensive projections software recommendations are welcome!

 

[DrewE]

What are you trying to project: static images, full-motion videos, short video loops, or...? How many projectors? How tightly do they need to be synchronized to each other? How fast is the ethernet connection in question?

For the software: what capabilities do you need it to have?

My hunch is that it's not practical to do what you'd like to do, unfortunately, but I could be wrong. At the least I think you'd need some sort of a computer or dedicated receiver/decoder box at each of the projectors. Others here are more versed in such things than I am. If you can get a separate ethernet cable run to each projector, you could use one of the (pretty inexpensive) video over CatX (X = 5e, 6, 7, etc.) cable converters available; Amazon has some (of possibly uncertain origin and quality) for roughly $30 a set.

 

[Luke_R]

Ideally for our production it will be a combination of static and video loop cues. We were looking at five projectors, with three rear projecting for ground mounted walls, and two front for the 'cloud' that hangs over the set. They should ideally move together. By ethernet, I was referring to cables that appear to be some form of CatX cable. Ideally the software would be able to coordinate the projectors to achieve the desired synchronization, and to spread an image/video across two projectors. Due two computer requirements, I realize that we may have 2-ish computers to run this, but that is better than our current plan, which is to use a computer for each screen running google slides.
I will look into the converter boxes for driving the screens, as that seems like a reasonable way to achieve the desired runs.

Thanks for the help!

 

[dbaxter]

If I understand you, something like this: https://www.amazon.com/dp/B08TLZ13WN/?tag=controlbooth-20 will address the transmission of the video signal to the projectors. You still have to generate the video content with a computer and software of some sort. Both Qlab for Mac, and Cue Player for Windows can do the job of generation and synchronization. At this time, Qlab has better video features for edge blending to spread an image than Cue Player. Both solutions will be able to drive more than one projector. I am currently setting up a 5 projector design for the play Silent Sky. Stay in touch and I'll let you know how it goes.

 

[Jay Ashworth]

If you're going to have 5 projectors, I'll assume you're renting.

Rent projectors with SDI inputs, and the relevant HDMI (or whatever) to SDI converters and coax, as a package. You'll be much happier with SDI transport than HDMI over Cat; the latter can be pretty flaky. I'm not fond of flaky transport, if I have a way to avoid it.

 

[rsmentele]

Another option, and how I transmit my signal, is HDbaseT. Many projectors are beginning to accept this protocol, which is transmitted via ethernet and can send control and video signal. So I just have a signal injector at my source and run directly to the projectors

 

[Jay Ashworth]

Another option, and how I transmit my signal, is HDbaseT. Many projectors are beginning to accept this protocol, which is transmitted via ethernet and can send control and video signal. So I just have a signal injector at my source and run directly to the projectors

One clarification: it travels over Category 6 cabling, not over Ethernet.

I haven't worked with it, though it does sound like a neat approach.

 

[danTt]

One clarification: it travels over Category 6 cabling, not over Ethernet.

I haven't worked with it, though it does sound like a neat approach.

To make It more confusing, I think it can carry Ethernet as part of the HDbase-t signal

 

[Malabaristo]

To make It more confusing, I think it can carry Ethernet as part of the HDbase-t signal

Correct, and also RS232 for control commands. The key point is that it can't be connected to regular Ethernet switches--just direct, point-to-point cabling that happens to use the same type of cable.

 

[Jay Ashworth]

Correct, and also RS232 for control commands. The key point is that it can't be connected to regular Ethernet switches--just direct, point-to-point cabling that happens to use the same type of cable.

Correct; that's the distinction I was trying to make: Ethernet travels over Category cabling, but not everything that travels over Category cabling is Ethernet PHY.

 

[macsound]

If it's over 100 ft for most of the video runs from the booth to the projectors, you might think about your Qlab computer or computers to be mounted in a central location between the projectors. Then a single piece of cat to the booth for control. You could then either use remote desktop/vnc or the Qlab remote to fire the cues.