Ethernet

[iamchristuffin]

OK, so first I think I should mention that I have searched for this topic, but it only return topics of why you could use Ethernet, not how.

 

Anyway, after seeing in Product specs that many desks can 'control xxxx fixtures via DMX, expandable to xxxxx via Ethernet', I got to wondering how this was done.

 

Hazarding a guess (it is just a guess though), I assume there is a single 'ethernet out' per dimmer rack/room, which all the dimmers somehow link into, which is then taken to near the desk, and converted into DMX?

 

Or it goes straight into the desk as an Ethernet connection?

 

 

Thanks very much guys!!

[johnhuson]

The most common scenario is to run Ethernet from the desk at FOH/Control to the stage and then have a series of Ethernet to DMX converters, each one giving you a number of DMX universes. The number of converters depends on the number of outputs on each one, number of required universes and the maximum number of universes the desk can produce.

 

Some consoles (the Hog 3 as an example) use remote boxes connected via Ethernet to actually do some of the processing, where as others are simply protocol converters which take a data stream produced by the console then split and convert into DMX universes.

[gareth]

Firstly, the way you appear to be thinking about the whole scenario is @rse-about-face. A dimmer rack (or other device) wouldn't have an 'ethernet out' - it would have an in. (Edit : well, OK, it might have an 'out' in the sense of a pass-through connector - which would have to be derived from some sort of internal 3-port switch built into the device.) Likewise, you wouldn't convert from ethernet to DMX then stuff it into a desk, as you seem to be implying ...

 

By and large, systems like this tend to work by taking a network output straight from a control desk, and running that to somewhere useful. This then goes into a node of some sort, which turns the information which is coming in on the ethernet connection into one or more universes of DMX, which you can then send to the devices that you're controlling. Many of the major console manufacturers build desks with the ability to work this way - MA, Flying Pig (sorry, I still find it difficult to think of Hogs being made by High End ...), Chamsys, etc. Many manufacturers work to the ArtNet protocol, as developed by Wayne Howell of Artistic Licence. Wayne's also written a book about this very subject, which would be a worthwhile avenue to research if you're really interested in finding out more about this sort of thing.

[Bryson]

Some, fancier, dimmers (and even a very few moving heads) will accept ethernet straight, too.

 

There are conflicting implementations, though. It's not as standardised as DMX. Yet.

[Tomo]

It's not as standardised as DMX. Yet.

It is now!

However the ESTA Streaming ACN standard was only ratified this year, so some manufacturers are only just starting to implement it.

 

The common protocols you'll see are:

 

ArtNet from Artistic Licence as mentioned above.

ETCNet 2 from ETC

MA-Net from MA Lighting

Streaming ACN (sACN), the new ESTA standard for DMX-over-Ethernet.

 

Many consoles support multiple protocols - for example Congo can produce ETCNet2, ArtNet, Avab IPX (rare in the UK) and sACN.

 

The big advantage of using Ethernet for lighting control is fairly obvious - if you're controlling a big rig of moving lights, and you've got a couple of media servers and a few hundred ways of dimming, you can either:

 

A) Run five or ten DMX cables up to the control position, and fit loads of DMX splitters around the venue.

B) Run ONE ethernet cable to the control position, put an ethernet switch rack by the stage, and fit several DMX output gateways around the venue.

 

This is especially handy when the control position moves...

 

The less obvious advantage is that the DMX output gateways are configurable - so every Universe of DMX is available at every gateway.

If you need Universe 5 on Stage Left, without the network, you'd need to find the DMX splitter for Universe 5 and run a DMX cable.

With DMX-over-Ethernet, you simply reconfigure the Stage Left gateway to output Universe 5 on an unused port.

 

Most gateways can also be reconfigured to act as inputs for when someone brings a console that doesn't support the local network standard, or doesn't support networking at all.

 

Finally - Cat5e is cheap. Really cheap.

And it's extremely easy to terminate (females) - I can do a good one in about 20sec, and I'm really slow.

My soldering is pretty good, but it takes me a good few minutes to properly terminate a DMX cable - mostly unwinding the braid...

[Jonny DMX]

I would assume you have already read this thread about entertainment ethernet control, if not then I think it raises some interesting points about ethernet based control networks like ACN. Additionally it sounds as if the OP's fundermental understanding of DMX is a little thin (my apologies if in fact you are an expert) you and others interested in DMX and ethernet based DMX may find Nick Mobsby's book Practical DMX ISBN: 1-904031-36-6 if interest.

 

http://images-eu.amazon.com/images/P/1904031366.02.MZZZZZZZ.jpg

 

Jonny

[David Buffham]

I think that DMX-over-Ethernet will become commonplace and I think its just a matter of time before Ethernet will be an integral part of lighting control infrastructure in the majority of theatres - and another skill required by lighting technicians.

 

We've just bought a relatively new console (ETC EOS) that doesn't have a single on-board DMX port! Just Power-Over-Ethernet ports for connecting over Ethernet to DMX gateway boxes using ETCNet2 or Net3 (ACN) protocols (with other protocols to follow, I believe). With the gateway configurability that Tomo mentions this offers great flexibility in system layout and also redundancy. Admittedly our system is quite small, but along with back-up processing we're able to quite easily put together a network infrastructure that means our overall lighting control system has no single point of failure, without undue complexity or cost.

 

However although CAT5e is cheap, what isn't cheap at the moment are POE switches with Ethercon connectors. We saw one 4-port switch at PLASA listing at around £400+VAT! I don't suppose there's anything particularly special about them; just that the connectors are more geared to this industry? Any reason why we couldn't build a standard Netgear ProSafe POE switch into our system rack and connect it to panel-mount Ethercons - for a small percentage of that cost?

[dosxuk]

And getting hold of Cat5E flexible black cable is a pain at the moment. Both Canford & SLX have had trouble getting hold of any for us.

[Pete McCrea]

Flexible black CAT5- Try TMB.

 

Ethernet switches with Ethercon ports would be ideal- not just lighting but video is starting to use ethernet hardware for both IP traffic as well as propriatry formats. I think for a while the cheapest option will be an ethernet switch with a second patch panel for ethercons.

[Grum]

Ethernet has been common place (in a way) for several years already.

 

I was working for an installation company as far back as 2001 and every installation we did included at least a basic ethernet run with tie lines around the building in at least 3 places (the control room, the dimmer room and one at stage level).

The more advanced installations included a full network including:

 

Switchers

Tracking back up PCs (for when your desk crashes)

File server PCs (so that in a studio complex you always have access to your show files even when you're in a different studio)

Dimmer monitoring software (to allow you to edit the dimmers softpatch, back up memories and even do a lamp round form your PC!!!!)

 

But then Nick Mobsby was one of our project directors.

 

At first I was very anti ethernet, I just didn't see the point when it was a case of using the same network as all of the office PCs, also I wasn't keen on the idea of having somany extra links in my control chain or converting my control signla form one thing to another and back again. I like to keep thing as simple as possible to minimise the chance of things going wrong.

These days however I've now seen enough ethernet systems in use to have faith in thier reliability, however I would still only use a completely closed network and I'd stay well clear of WiFi, with so many gadgets using it these days you can bet your @ss there'll be someone trying to hack your network just to try and get some free internet from your dimmers.

[Lee House]

And getting hold of Cat5E flexible black cable is a pain at the moment. Both Canford & SLX have had trouble getting hold of any for us.

 

 

Please contact me at Lee.House@aclighting.com and I will be able to help you with your Cat5e troubles.

 

Kind regards

 

Lee House