Cat5 Controlled Stage Lighting

Kyle's icon

To Whom It May Concern;

I am a college student whom has just started to learn the ropes and bounds of MaxMSP through one of the courses I am taking for my Music Technology major. It seems like a very powerful program and I was hoping that I may be able to use it to accomplish the following project idea...

Well, I as well as a few other college students am responsible for helping to lead worship at a Campus House (college ministry), here on campus. We currently have a small stage setup, and most of all, our budget is pretty small. Currently, we have floodlights used to illuminate the stage, and these are wired into simple wall dimmer switches so we can change the brightness of the lighting. (The floodlights surprisingly provide adequate lighting and it looks decent too, since it is for a small scale stage/budget.)

As I and some other leaders of the ministry were discussing what we could do to better improve the ministry, one item that came up was to improve the lighting. This is when we started to share ideas we had for improving the stage. One item in particular was the current lighting we had, and how it wasn't flexible in the sense that it could not be controlled from back in the sound booth...that someone had to control them on the wall with all of the switches. Having worked with MaxMSP, I figured that this might be a type of project that would be suitable to be programmed in MaxMSP.

My vision would be to devise a way to build a few light racks/boxes (racks of 4-5 floodlights), all white in color, that could be hung from the rafters in our building above the stage. Then to choose colors, we could simply have the capability to drop gels in front of the white lights of our choosing. This would allow for more colors and color combinations that the current "red-only" lighting that we have to use. Then my thought was to somehow use inexpensive wiring (cat5 was my first thought) to interface with each floodlight or to interface with some sort of micro-controller that would interface itself with each floodlight). The Cat 5 or other type of cable could then be ran back to our soundbooth, interface with a computer, or the same hub that the computer is connected to, and then have a MaxMSP application running on the computer with sliders and toggles to control the lights. Functions that I can imagine that would need controlling are being able to adjust the brightness/dimness of each floodlight individually, the ability to turn it on or off, and also the ability to make different lighting sequences in MaxMSP so that different common lighting setups would be automated.

I am intending on speaking with my MaxMSP professor who is very fluent with this program. He is the one who had advised me to post ideas on the forum as several knowledgeable individuals would be able to help me brainstorm and offer advice or even other ideas along the process. I am also hoping to ask if he would be willing to help me out with diving into this project and programming it since it is pretty involved and I have never heard of it being done before. My only concerns that I have for pulling this off is how I would approach the concept of controlling each floodlight (it's on/off state, and level of brightness) individually. Obviously, Cat 5 cabling cannot handle high levels of current or voltage for that matter, so would I have to somehow interface the lights with some type of controller, transformer to amplify the voltage, etc? Or, could there just be a way to control the lights through Cat 5 that would interface to switches that would handle the larger current/voltage loads of the floodlights? Also, there would need to be a device/program that would be able to "send/push" data sent from the computer's USB into a device that would convert the signal to a RJ45 jack, etc. then send out different values from a MaxMSP program as some type of data value to the multi-controller/mini-computer, etc. that is connected to the floodlights, which would interpret the data and control the lights accordingly.

Please if anyone is willing to start brainstorm, I would greatly appreciate it. I am very eager to start to tackle this feat and I know that MaxMSP is definitely capable of pulling off a project like this. I know the majority of the hard work in pulling off a project like this will be all of the interfaces, wiring, and creating hardware devices, but if all of you wonderful MaxMSP geniuses out there would be willing to start contributing your ideas, and how you might approach, work on, and solve this project, I know I would greatly appreciate it.

Please let me know any thoughts, I already something like this is ridiculous, and we should just be purchasing real lighting, however, I am wanting the challenge of solving this problem differently.

Thank you so much for your time!
Kyle

Visibleman's icon

Am i right in thinking you just want to be able to dim the spots remotely?

Have you got a DMX dimmer (like > HERE <, can get them with the three-pin mains socket) on the lights? As that's the easiest way to go about it.

Once you have DMX you can either use a DMX desk/controller, like > SO < or you can get ethernet DMX boards and DMX Pci cards and then you could create a maxmsp patch to control the lights.

Another link worth looking at - > HERE <

Kyle's icon

Yes, I had thought about DMX, but our lights are simple floodlights (ie. 3-prong 120V plugs). How would I get those to interface with a DMX dimmer? Also, would there be some other feasible way of controlling the lights without using DMX or having to invest in pricey DMX controllers? Wouldn't there be a way to use switches and micro-controllers to control simple on/off and dimmer functions of voltage or current which would control the lighting? I am thinking something creating something with electronic components from scratch and having to solder, etc. I am interested in the dirty work of creating a system like this from scratch if someone would have ideas or a general idea of how to approach a solution to this project.

Please let me know if there's any other more 'crude' and primitive way of doing this without having to use costly DMX controllers/dimmers.

Thank you,
Kyle

Kessito's icon

Check this out:

It's great stuff (I've used the relays myself with MAX for a project) and very easy to control with RS-232 or ethernet or zigbee or bluetooth)
Their software uses a virtual COM port which you can use in MAX with the serial object and it is as simple as sending commands like this:
1 1 0 (lamp 1 of controller board 1 off)
1 1 128(lamp 1 of controller board 1 50%)
1 1 256 (lamp 1 of controller board 1 100% on)
etc.

good luck
Kessito

Visibleman's icon

I'm guessing your spots have plugs like > This < (they usually do on spots/floods, newer lights tend to use IEC/Kettle Plugs)?
You can get DMX dimmers that you plug the 3-ping plug into, like > this < - it's wired to the mains (mostly single phase, although bigger units require three-phase), and then each light is plugged into a socket and you have DMX connections (in and out - out is for chaining to other dmx dimmers) for control.
Check out ebay or the likes, might be able to pick one up cheap.

But yes you could go down the route of making something to switch/dim the lights. You'd need something like the DMX Relay Board or DMX Switch as shown on > this < site. Or something like > this < would work too, although a quick google doesn't seem to show anything about them.

What Kessito posted though, looks like it's a PWM board that switches DC (12v by the looks of it), useful for controlling LEDS or motors but you couldn't connect it to 120v/240vAC (could be wrong as i only quickly read it).

Personally i'd keep an eye out for a cheaper DMX dimmer and serial/usb to DMX board, and head down that route - it beats playing around with mains AC.

seejayjames's icon

Kyle wrote on Tue, 24 March 2009 17:34 I am thinking something creating something with electronic components from scratch and having to solder, etc. I am interested in the dirty work of creating a system like this from scratch if someone would have ideas or a general idea of how to approach a solution to this project.

Please let me know if there's any other more 'crude' and primitive way of doing this without having to use costly DMX controllers/dimmers.

There's always methods to do this, but I for one wouldn't recommend it for this application at all. Dealing with A/C and large currents, and custom electronic components, you need to know what you're doing, you'll definitely have problems, and it'll take a ton of time (and you can set things on fire, fry your circuits, etc.) So I'd say invest in a DMX controller which has enough oomph to run the power levels you need, and has been tested and rated fine. It's more than worth the money for the time saved and the safety issue.

Formatting the commands to go to DMX can be done in a lot of ways---I used Olaf Matthes' DMXUsbPro object (for about $15) which sends simple Max lists to your channels via USB, which the DMXUsbPro from Enttec then spits out as DMX. Yes it's more money but you're up and running in no time. Probably you can get one of the boxes cheap on EBay.

(If anyone knows of a simpler, USB to DMX solution, which you can simply send lists out of Max via the [serial] object and it magically becomes DMX, that would be great---it seems like such a thing should be straightforward and cheaper than what I've found.)

It's great that you want to get down and dirty with the electronics, and I encourage you to do that with things like the Make Controller, Arduino, or custom stuff. If you get the Enttec DMXUsbPro or similar, and get it working with Max, you can use it for other fun stuff like LED installations. You can learn a lot about Max at the same time through these projects. For high-current applications like this, though, I'd steer well clear of the DIY route for headache and safety issues.

Once you have your working patch, look into [pattr], [preset], [line], and [mtr] for cool control options. A bit of time here will make your show as awesome or as elegant as you want.

Tj Shredder's icon

this should get you going to connect it to Max...
(don't have one, but if anybody has experience with it, chime in...)

Stefan

the_man361's icon

midi to dmx with a midi controller with knobs on is an idea, also you could control the lights serially using an arduino with max for the physical interface (big knobs etc), flexible options for switches and whatnot