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What the heck is DMX?


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Posted

So I'm entering my second year in XMAS of 2015, and I had a question - what the heck is DMX? How will it improve my show? Is DMX for everyone?

 

LN

Posted

http://en.m.wikipedia.org/wiki/DMX512

DMX is a data protocol mainly used in the event and theater world. Think of it as another language to talk to lighting or other devices.

Does it improve your show? Well - if you ever want to dive into the world of pixels or anything without a LOR label you should get a little bit familiar with it. If you stick to anything LOR - no need to really worry about it.

  • Like 1
Posted (edited)

I think most who do this hobby will venture into DMX to some extent, even if it is just to do wall wash floods.

 

On my website I have several DMX presentations. Seasonal Entertainment, Geek My Tree and Holiday Coro all have material or videos explaining DMX.

 

It is the gateway into RGB & pixels as pointed out above.

Edited by zman
Posted

zman, viennaxmas,

 

Thanks! I wanted to explore with RGB some but I kept seeing/hearing DMX and needed some more info. I am so glad that there is such a large community that can help people like me out. Thanks for providing resources!

 

LN.

Posted

HI,

DMX is a very old protocol that is still used for controlling theater Lighting. With Current Changes in Technology, We are also using it in our displays as well. I would get the starter manual from http://auschristmaslighting.com/forums/index.php?topic=1211.msg9961#msg9961

 

You will have to sign up for an account (Free) 

 

DMX is used heavily with RGB either in E1.31 or in true DMX XLR Connections. The Dumb Strings (where all the strip/lights change to 1 color) use only 3 channels for the entire strip (these are the 27 channel controllers you see -Usually with XLR Connection- There is an adapter if you want to use ethernet instead of DMX Cable. ) The Intelligent Strings Use either Sandevices,J1sys or Pixelite and they are also DMX, just they use ethernet cable and the ethernet port (or switch) on a laptop and they increase your control and channel count quickly as each light on a strip/string is controllable.

 

Also take a gander at DIYLightAnimation.COM. They do a lot more DIY work. :)

 

Kip

Posted

Kip, Zman, and Vienna,

 

I can't express how grateful I am to have someone who can explain this so easily. I feel dumb now (as I always do when I realize it such an easy answer to an even simpler question), having looked into strobe lights and other RGB lights. Thanks for your advice. I will look at all the abundance of resources I have at my fingertips now.

 

LN

Posted

LN,

No worries. Everyone, and i do mean almost everyone who stands at the DMX door gets the shakes over it for some reason. Folks are fine with LOR, and it just takes a while for the light bulb to turn on around what DMX is, how it works, and how to get it working with LOR.

Keep asking questions.

Posted

Okay... so if I want to buy this strobe light (http://www.cheapdjlighting.com/Chauvet_Mini_Strobe_LED_p/ministrobeled.htm) [pictured, just one strobe in this example] and add it, do I have to buy a whole DMX console/controller? (e.g. http://www.cheapdjlighting.com/Chauvet_Obey_10_DMX_Lighting_Controller_p/obey%2010.htm )

 

 

ministrobeled.jpg                                                 obey10.jpg

 

Also... what do you recommend (retailer/brand) and (price) -wise for a beginning DMX user? Is there any additional software I need on my machine (other than LOR?)

 

LN

Posted (edited)

First of all, the strobe you list is not DMX if you look at the manual.

 

Next do you need a DMX console to run or test DMX fixtures with LOR? Well that depends, but mostly I doubt it. LOR within the Hardware Editor, has a software console built in that works great.

 

I have used a console when I am troubleshooting or learning a fixture, or if I need to get movement extents like on a yoke, and did not want to fire up the computer, hook up the DMX universe and play inside LOR.

 

Regarding brands/pricing. That is a personal preference. Most on forums and social media will tell you to go in a Do It Yourself (DIY) direction. I say do what you want. IMHO, I would look at American DJ products before Chauvet (I only say that because you listed a Chauvet strobe). ADJ has prolly better products and service.

 

Getting an inexpensive fixture is a good way to play with DMX and get used to it. To control DMX, purely a single or maybe 2 DMX Universes, LOR is fine and will do the job for strobes, floods, yokes, scanners, foggers, etc.... Once you get into RGB Pixels, decisions have to be made on both the hardware and software.

 

Keep asking questions

 

P.S. if you plan on using most DMX fixtures outside, you will need to weather/waterproof them. To buy weatherproof lights is very expensive.

Edited by zman
Posted (edited)

There are several posts in these forums about how to get dmx working.

But the quick rundown is, if you are using your pc you will need something to translate the protocol.

LOR is one protocol. Dmx another. They must stay seperate.

Most get an entec pro or entec pro compatible dongle that connects to your pc via a USB port.

If you are not using a pc then you have to look at the LOR iDMX or othe LOR to dmx bridges.

You of course could look at e 1.31 devices to add pixel control and dmx in one component.

Keep in mind that each dongle or the iDMX is just one universe. The e1.31 device could be 1 or more dmx universes.

Once you have your dmx universe, which is just 512 channels, then you add your dmx components or controllers. Rgb lights still will need a controller to function. But an rgb light and 27 channel controller is pretty cheap. On the other hand, you could purchase the dj components you are looking at and do some different effects other than just plain rgb. This can get pricey fast.

Zman is a good reference for your dj components. Not many in these forums use the dj components.

For pixels and just plain rgb....lots of info in the forums. Also great videos at holiday Coro to help you understand.

As far as software...you will need the advanced version of the LOR suite. The LOR software is all you need.

At times I think an external controller would be helpful. Guitar center has a basic 3 channel dmx controller for $50. But it is not necessary....especially if you are just doing rgb.

Edited by sax
Posted (edited)

Ok so this is a DMX-operated strobe (http://www.adj.com/freq-5-strobe). If I want to use this with my current show, which doesn't have any other DMX elements, what you're saying zman is that I most likely will NOT need a DMX controller/console. Am I correct in saying this?

 

FYI, I'm using a PC and two LOR controllers mounted to wood to run my show . I currently use 22 LOR channels. If I add the DMX fixture, that is equivalent to ... 1 LOR channel ... right? (My "light bulb" for DMX is like 70% on right now, slowly increasing. ;) )

 

Just trying to set the ground, so you can understand my perspective. It seems like RGB/Pixels is going to be out of my budget (I looked at GeekMyTree and they are quite pricey.) Has anyone considered using their lights to make their own Mega Tree? I was debating it... but still too expensive.

 

zman, I read your presentation on DMX Basics, which helped quite a lot, frankly. Thanks for the information. I use two separate computers (my father and I sequence separate songs and share them on the orange computer) to do the sequencing.

 

Thanks again, everyone! I really appreciate everyone's help.

Edited by lightingnewb
Posted

Re-read what Sax provided good info there. To do DMX you have to have a means of outputting DMX You need:

 

1. LOR Advanced software

2. DMX Dongle - This can be another RS485 - iDMX (LOR) - Enttec Open or Pro. The only "enttec" compatible DMX dongle I have experience that works without issue is, the DMX King. Lots of vendors say they have DMX dongles compatible to Enttec. Not to knock vendors, but there have been many a problem with said knock offs over the years.

3. Cabling appropriate to connect things up

4. A terminator at the end of the chain (some will argue this is not necessary, well, when y9ou are troubleshooting issues, this is the first thing to  potentially be the problem)

 

However all this said, you have mentioned, you are new to DMX, wanted to use a strobe, and now pixels (Geek My Tree)

 

Exactly what is it that you want to accomplish? The more you look, in this arena, the more slippery the slope gets, and the more complex it can become.

 

Sequencing is easy

Posted

Ok so this is a DMX-operated strobe (http://www.adj.com/freq-5-strobe). If I want to use this with my current show, which doesn't have any other DMX elements, what you're saying zman is that I most likely will NOT need a DMX controller/console. Am I correct in saying this?

That strobe can take DMX input (can be connected to a DMX network). Your current show does not have a DMX network, only an LOR network, which is connected to your 2 LOR controllers.

 

There are basically 2 ways to get your computer (with LOR software) to output to a DMX network:

  1. A DMX dongle can be plugged into a USB socket on your computer. There are several dongles that can be used. One is another USB-485 dongle like you are using to drive your LOR network, but this is not optimal, because it makes the computer do more work, which can result in timing problems (that was a problem in an earlier LOR version). The Enttec USB Pro is a good choice.
  2. To keep things simpler (on the computer side, at least), you can install a LOR-to-DMX protocol translator on your LOR network. 2 choices here are LOR's iDMX1000 or San Devices' ELOR.

 

FYI, I'm using a PC and two LOR controllers mounted to wood to run my show (see image). I currently use 22 LOR channels. If I add the DMX fixture, that is equivalent to ... 1 LOR channel ... right? (My "light bulb" for DMX is like 70% on right now, slowly increasing. ;) )

 

In a sequence, 1 DMX channel just like 1 LOR channel. For instance, that strobe you posted has different modes so it could be 1, 2, 5, or 7 channels, depending on how you configure it.

 

If you use a DMX dongle, then this adds a 512-channel universe. If you use a LOR-to-DMX protocol translator, then it adds 1 controller to your LOR network that has up to 512 channels. In that case, the sequenced editor/ hardware utility treats it the same as the other LOR controllers.

 

Just trying to set the ground, so you can understand my perspective. It seems like RGB/Pixels is going to be out of my budget (I looked at GeekMyTree and they are quite pricey.) Has anyone considered using their lights to make their own Mega Tree? I was debating it... but still too expensive.

 

Last year, I went big and built a 1200-pixel mega tree. It cost about $1000. Most of that cost was the pixels themselves.

  • Like 1
Posted

Re-read what Sax provided good info there. To do DMX you have to have a means of outputting DMX You need:

 

1. LOR Advanced software

2. DMX Dongle - This can be another RS485 - iDMX (LOR) - Enttec Open or Pro. The only "enttec" compatible DMX dongle I have experience that works without issue is, the DMX King. Lots of vendors say they have DMX dongles compatible to Enttec. Not to knock vendors, but there have been many a problem with said knock offs over the years.

3. Cabling appropriate to connect things up

4. A terminator at the end of the chain (some will argue this is not necessary, well, when y9ou are troubleshooting issues, this is the first thing to  potentially be the problem)

 

However all this said, you have mentioned, you are new to DMX, wanted to use a strobe, and now pixels (Geek My Tree)

 

Exactly what is it that you want to accomplish? The more you look, in this arena, the more slippery the slope gets, and the more complex it can become.

 

Sequencing is easy

So the strobe light is just a channel I want to add as a feature. The Mega Tree got a bit off-topic, but I wanted to build my own Mega Tree using Geek My Tree - pricing though, proves to be tough. I probably will not make the mega tree this year. I will at least buy some strobes (the first one I linked), since they aren't DMX [and are CHEAP!], so that I can research and learn more about DMX. I've been frightened, and a bit overwhelmed I think, about the whole thing with DMX... I'll give it a couple of weeks' rest while I prep for college starting again and finishing posting my website. I'll keep you all posted on where I'm swayed and what I intend to do in my next steps.

 

LN.

Posted

Z Man is the authority on DMX.  but maybe this will help a little.  

DMX is a protocol for sending data  like LOR is.  Think of LOR as English and DMX as French.   If the controller you are using speaks French (DMX) you will need to send it commands in French,  LOR can send out commands in both English and in French (if you tell it to) as well as sending out commands that can be packaged in French (E1.31).  

LOR tells the controller what to do and when, in the language the controller understands.  In order to get the data to the DMX controller LOR needs some additional hardware (since LOR only includes the hardware to speak to its own controllers).

You need to add a "Dongle" or crossover cable.  A DMX controller and power supply or DMX device that has its own controller and power  internally (smoke machines etc).

There is a single limit of 512 channels (DMX universe)per dongle.

E1.31 is a means if sending DMX data over the Ethernet connection on your computer. E1.31 does NOT require a dongle, only a E1.31 controller same 512 channel limit except E1.31 controllers can handle multiple universes of data and you can use a 'Switch" (think of it as a splitter) to connect multiple E1.31 controllers to the same cable (like you daisy chain LOR controllers but not necessarily daisy chained.

To use DMX over E1.31 you do NOT need a Dongle only a E1.31 controller and power supply. 

Of course you will need to setup LOR so it will know what to do  and how.

Sounds MUCH more complicated than it really is.

  • Like 1
Posted

Here is how I understand it, first and foremost you need to decide what items you want in your display.  If you just want blinky flashy with a few strobes then you may not want to dive into the DMX world just yet.  LOR has a controller that can control some DMX devices if you want.

 

Where DMX IMO is a benefit/cool has to do with the type of devices that are out there for it.  Stage and professional lighting tends to be DMX, the cool swivel lights you see at concerts, laser lights (ones with various colors, etc.).  things where you not only need to change colors but change directions the light is pointing.  Also most high end fog machines have DMX ports.

 

I would try to outline what props you are going to want first, then most on here can help with whether or not you should use LOR and its controllers, SansDevice, etc. or dive into the DMX world.  I have always thought of DMX as being used on high end lighting.

Posted

Jerrymac, are you speaking of an ethernet switch for splitting the lines to different DMX controllers?

Posted

An ethernet switch is used for to connect multiple E1.31 controllers, but NOT DMX controllers (unless you like letting the magic blue smoke out of something).

 

 

DMX and LOR ride on RS-485 serial.

E1.31 rides on ethernet.

 

Although both use Cat 5 or Cat-6 cable and may use RJ-45 connectors (DMX often uses a different connector), ethernet and RS-485 are not the same and connecting them together may let out the magic blue smoke.  Don't do it!  Personally I use different color Cat-5e cable so I can tell them apart.

Posted

Yes Ethernet switch (I just compare it to a splitter for ease of understanding). 

One thing you want to be VERY careful of with multiple protocols is NOT to get the cables mixed up.  I use LOR, DMX 512 with a dongle and E1.31 at the same time and use different Cat 5 cables for each.  Plugging LOR signal into a E1.31 or DMX device can cause failure (5 volts on different wires).

Posted

Plugging LOR signal into a E1.31 or DMX device can cause failure (5 volts on different wires).

 

E1.31 runs over Ethernet, which uses pulse transformers. Getting the typical failure current of these transformers is not easy, but modern Ethernet transformers are designed to be used with Power over Ethernet (PoE), which is typically 350mA. The auxiliary voltage pair from a LOR controller is 9v, and can probably supply over an amp, which is enough to destroy an Ethernet transformer.

 

Therefore, don't plug a LOR controller into an Ethernet device. It will probably destroy the Ethernet port.

 

On the other hand, the typical RS485 transceiver chip in a DMX controller has a maximum short-circuit current of less than 250mA, according to a data sheet I found online. This would probably not harm an Ethernet device.

 

Plugging a LOR controller into a DMX device also probably wouldn't hurt it, first because pins 3 and 6, where the voltage is present, are typically not connected to anything in a DMX device, and second because a RS485 receiver can handle 9v with no issues.

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