Film-Tech Forum ARCHIVE: Automation + DMX lighting control

This is topic Automation + DMX lighting control in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by David E. Nedrow (Member # 4981) on 06-10-2009, 04:46 PM:

Does anyone have experience with integrating DMX lighting controllers into a projection automation setup? At the least, into the show start/show end queuing?

We'll be using programmable LED fixtures for house lighting and auditorium wall washes.

For now, we're looking at a Kelmar Series IV but that may have to change depending on the requirements of the integration.

-David

Posted by John Walsh (Member # 168) on 06-10-2009, 06:12 PM:

Most dimmers used for theaters are very generic; simply make a connection between two terminals and they operate. The automation must output 'dry' contacts which operate for 'bright' , 'mid' , etc.

A quick look at the DMX; it seems to be a programmable unit. A better question right now might be; what projector automation are you using?

Posted by David E. Nedrow (Member # 4981) on 06-10-2009, 09:34 PM:

quote: John Walsh
Most dimmers used for theaters are very generic; simply make a connection between two terminals and they operate. The automation must output 'dry' contacts which operate for 'bright' , 'mid' , etc.

Right, and that's how the theatre currently "works".

Basically, we're replacing incandescent (and mechanically "dimmable") wall wash lighting with LED lighting that can't be mechanically dimmed. It requires a DMX protocol command that sets the level of the light. These commands come from a DMX light (or show) controller and are transmitted over a DMX control cable, which is basically a multi-wire cable with XLR connectors.

I know that the automation system we're looking at (Kelmar Series IV with changeover) has dry outputs, etc. I'll probably have to fabricate something to take the high/low from the automation and convert it into a DMX trigger signal that is then sent to the lighting controller, which will then take the appropriate action with the lights. The projection, curtain, and masking would remain under the control of the projection automation. I may be able to leverage pre-existing serial to DMX converters.

I just wondered if anyone had set something like this up before.

DMX512-A
Kelmar Series IV

Posted by John Walsh (Member # 168) on 06-10-2009, 10:16 PM:

OK, got you now.. you need something to take in an I/O input and output a DMX protocol serial string using the RS485 interface. I admit I don't know much about DMX, but there should be something like that. A call to DMX might help; they may have gone through this and have something that lets you hook up something with dry contacts. I would guess that a cheap 'black box' (like a simple Microchip microcontroller product) can do this, but that would require you to do your own programming.

I wonder if a Strong CNA automation could be mde to directly output a serial string, I think it uses RS449, which (electrically speaking) might convert easily to most balanced lines using op amps. But you'd have to pay someone to write the code.. expensive.

Posted by David E. Nedrow (Member # 4981) on 06-10-2009, 10:31 PM:

Cool, thanks for the info. I also tracked down a lighting controller that appears to be able to handle analog triggers (dry contact), which might simplify my setup. I need a controller to program the lighting and one of these would remove the need for something between the automation and the controller.

Zero 88 Controllers

.... Hoooboy!, but not for $15,000

Here's a device from Lanbox that should be adaptable to what I need and is reasonably priced (US$450).

Lanbox-LCM

Posted by Tristan Lane (Member # 1169) on 06-10-2009, 11:44 PM:

I'm working with similar lighting on a new project where our sconce lighting will be LED, requiring a 0-10v dimming signal. DMX isn't totally needed as there are many cheap 0-10v controllers out there that will allow you to program set points and use contact closure to initiate those presets.

This is all assuming that your LED lighting is utilizing 0-10v for dimming. If it is in fact DMX, the lanbox won't work as it does not give any provisions for dry contact closure.
Check Lutron and ETC for those. Theatrical lighting isn't my specialty, hopefully someone else can chime in with more detailed info.

Posted by Demetris Thoupis (Member # 833) on 06-11-2009, 02:05 AM:

Sunlite provides a very convenient box which has trigger relay inputs to recall "scenes" programmed via USB. I've used them several times and they work flawlessly. They even have FADE times and preprogrammed scenarios for lighting changes. Check this site for more info