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Craven Sound
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 Post Posted: Wednesday Oct 15, 2003 
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What's the dillyo with it? If I have 4 intelligent fixtures, do I need dimmer packs AND the lights? Or can the controller handle them by itself? Is there a limit to how many fixtures/dimmer packs you can daisy chain? How are the lights manipulated as far as controlling the features of the fixture? (ie, gobo, color change, mirror spin, etc.) Any other suggestions would be great. Thanks!
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facingwest
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 Post Posted: Wednesday Oct 15, 2003 
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Redawg would be the one to talk to about DMX lights. He's the one that spent all the work and time into The Castle Pub's system and knows it very well. dsolinski@hotmail.com is his email addy and I'm sure if you had any questions, he'd be more than happy to help you out with anything.
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Ron
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 Post Posted: Wednesday Oct 15, 2003 
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You shouldn't need dimmer packs with intelligent lighting, if they dim it will be done internally. You can buy DMX controlled dimmers for any par cans you may want to use.

There are a lot of controllers out there. In general, a DMX 512 based system can control 512 different channels. Some lights listen to more than one channel, but usually no more than four. The effects are generated by the controller and sent in a digitally encoded serial format (RS485) over a differential XLR line.

Think of DMX as working this way...

Let's say that you have three dimmable lighting fixtures. You assign each fixture a unique identification number, 1-3, and then wire them with DMX. Through DMX, you can then say "1:50%", and lighting fixture #1 recognizes his ID number and responds by dimming to 50% brightness. If you say "1:50%, 2:100%, 3:0%", the fixture with ID 1 goes to half-bright, ID 2 turns on full, and ID 3 turns off.

The ID number of a fixture doesn't necessarily have any relationship with its physical position. Fixtures 1 and 4 could be close together, and number two would be way far away.

There isn't necessarily a one-to-one relationship between ID numbers and lighting fixtures. You might have a dozen fixtures that are set to ID 3, all coming on, turning off, and dimming together. And you might have no fixtures at all set to ID 2. The control console doesn't care. It happily calls out "If there is anybody listening to ID 2, go to 75%!"

Now let's go a bit further with that.... Let's say that you have a lighting fixture that is not capable of dimming; it can't even turn on and off. But it can change color. This clever fixture might still be usable via DMX. All it needs to do is use the number that it is given and interpret it, not as a dimmer value, but as the color. Perhaps 0-33% means red, 34-66% means green, and 67-100% means blue.

So, what if you had a fixture capable of both dimming and changing color? Perhaps it listens for two ID numbers. ID 1 might indicate the intensity, and ID 2 tell the color. Thus the command "1:25%, 2:75%" means quarter-bright blue. And from a distance, you can send "1:50%, 2:50%", and the fixture cheerfully goes to half-bright green!

The best intelligent lighting fixtures dim, change color, move around, and project gobo shapes - all under DMX control.

That's the power of DMX - since the lighting fixture gets to decide what to do with the number that it is given, you can control almost anything - laser scanners, fog machines, mirror balls - just name it, and somebody probably has it running on DMX.

There are things that you shouldn't use DMX for. DMX has no error detection or correction, so it is possible that a glitch in the transmission might accidentally turn on something when it isn't yet ready. This isn't a big deal if the ID is assigned to a light, which might flicker, and probably won't even be noticed. But if the ID is being used to control pyrotechnic special effects or something else potentially life-threatening, a glitch in the line is potentially disasterous.

DMX should never be used to control dangerous things. Also, keep in mind that DMX only conveys the control information, not power. Every DMX fixture will also need a source of AC power.
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redawg
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 Post Posted: Wednesday Oct 15, 2003 
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Here is what I got out of all the time I spent with these lights. The Castle has DMX lights as well as par cans and dj lights. You don't need to plug any DMX lights into a dimmer pack (you just need to get power to them) but you need DMX dimmer packs in the chain if you are gonna use non DMX lights too. If you have just 4 DMX lights, you connect them all together with standard mic cables. If you want to add par cans or any other non DMX light, you need to have DMX dimmer packs (these are way cheaper than standard dimmer packs). You connect the entire show together with mic cables (in no particular order). This is where the dip switches come in. Every DMX light has 10 dip switches on it. The DMX dimmer packs are digital. This is so easy, it's great. Each dip switch represents a number. This is the standard formula for ALL DMX lights:

Dip switch 1 = 1
Dip switch 2 = 2
Dip switch 3 = 4
Dip switch 4 = 8
Dip switch 5 = 16
Dip switch 6 = 32
Dip switch 7 = 64
Dip switch 8 = 128
Dip switch 9 = 256
Dip switch 10 = 512

Now each dip switch needs to be in the on or off position. Say you want your first light in the chain to be on channel 10 on your light board. You would need to put dip switches 2 and 4 (the numbers on the right add up to 10) in the on position. DAMN I DON'T WANT TO MAKE THIS POST TOO LONG. Say you want your next light to start on channel 19 on the light board. You need to put dip switches 5, 2, and 1 in the on position (the numbers on the right add up to 19). You cannot overlap channels on the light board. The thing with DMX lights is they eat up channels on the light board. One of those Mighty Scans takes up 6 channels on the light board (thats only in program mode). Please don't confuse light board channels with DMX channels.

fader 1 is left/right mirror movement
fader 2 is up/down mirror movement
fader 3 is speed
fader 4 is color change
fader 5 is gobo change
fader 6 is dimmer/strobe

That ties in with what Ron was saying. When you slide the faders up and down. The mirrors move, the colors and gobos change and you can dim and strobe. All you have to do when you add DMX dimmer packs (selectable number of channels) is set the digital display to what ever channel you want it to start on the light board. I could go on about this. I hope I was of some help to you. Please feel free to e-mail me or better yet stop in the Castle Pub. I am there almost every day. I am running sound Friday and Sunday this week. I'll gladly take the time to show you anything you want to see.
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redawg
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 Post Posted: Wednesday Oct 15, 2003 
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But then check this out. Our front 2 DMX lights (the Rainbows) have the SAME dip switch settings so both lights act as one. Same with our drummer lights (Rainbows too). I never toyed with a light board with a joystick on it so I can't help you there. I recommend you get a light board with at least 48 faders on it. You'll be totally covered. The Rainbow lights are only 2 channels (2 faders, not 2 DMX channels) on the light board. 1 for dimmer and the 2nd for color select. Same for the DMX strobe lights. 1 fader for dimmer and the 2nd fader for strobe speed. Again the dip switch settings on the strobes are the same so fader 1 controls brightness for both strobes and the 2nd fader controls the speed for both strobes. There are other combinations for the dip switches as well. I doubt you'll ever have to go that route.
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Ron
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 Post Posted: Wednesday Oct 15, 2003 
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Good info redawg. The lights I've seen only used 9 dip switches. With 10 you can program 1024 DMX channels if the controller supports it.

Have you checked out any of the PC based controllers?

AxisDmx makes a 512 channel interface that plugs into your computer's USB port for $499. If you buy the hardware the software is free. It would mean an unlimited number of programs, and think of what you could do with game controllers! Razz The pros use the touch-screen interface, but they are pretty steep in cost.
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redawg
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 Post Posted: Thursday Oct 16, 2003 
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Hmm. Interesting. Now you have me curious. What kind of lights did you check out? WOW, 1024 DMX channels. LOL, I could get lost in that. If you only had 9 dip switches on a light and the numbers had to double themselves, how would you get to 512? Gonna have to do some research. We put those lights in the club this past spring. I think I still have a lot to learn about them too. I wish I could get my hands on one of those joystick light boards. I'd love to try the computer software. I was actually down at the End Zone in Port Matilda tonite (Thanx for letting me in for free Larry). My god he put thousands of dollars of Martin lights in his excellent club. He has the computer software to control his whole light show. All the Martin lights he had used digital display in place of the dip switches. Very neat.
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Craven Sound
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 Post Posted: Thursday Oct 16, 2003 
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The dips uses the binary number system; that's pretty easy to remember. Thanks for the info. Next time I'm at the Castle, I'll be sure to ask for a tour of the lighting.

Mike
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lonewolf
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 Post Posted: Monday Oct 20, 2003 
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DO NOT connect intelligent lighting to a dimmer pack channel. They need to draw 120 volts at their rated current to run the electronics. If you lower the voltage with a dimmer pack, you could fry the light's control electronics by drawing too much current or vice versa. You should use RELAY packs to turn intelligent lighting on and off. Same thing for other lights with transformers in them, like most low cost pinspots.

The easiest thing to remember: If an intelligent light has DMX I/O on it, you don't need a relay pack. If it doesn't have DMX I/O on it, you need a relay pack.
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Craven Sound
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 Post Posted: Tuesday Oct 21, 2003 
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I have an older 32 channel non-dmx NSI board, (plus softpatch= 128ch) and found this translator very interesting. The guy also makes a DMX to microplex translator as well. It's a whole lot cheaper than buying a new DMX controller!

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2566520462

Mike
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