LED Par Cans

[justanothertechie]

Hello - I'm new here so hoping you can give lots of advice!

In our school we are discussing purchasing some LED Par Cans. We have typically used conventional cans with gels but feel that we could benefit from the use of new LED fixtures. However before we go out and buy any I wanted to know if we would need to buy anything else to make them 'work'? We have a lighting desk (Zero 88 Frog. NOT the fat frog version) but I wasn't sure whether this would support their coloring changing ability? Is there anything else we would need?

Thanks!
JAT

 

[techieman33]

Any console that supports DMX should be able to control LED pars to some extent, you may have to patch them like conventional fixtures and manually control all of their functions with the faders. You'll need plenty of DMX cable to run to them, not mic cable, but real DMX cable. If you don't have constant power available on your electrics you'll have to figure out how to get power to them. You'll probably also need an opto-splitter so you can split the DMX coming out of the console and have separate runs to the LED's and your dimmers.

 

[len]

Make sure you test drive the RIGHT fixture for your venue, your needs, etc. The quoted stats on a lot of the Pacific Rim products are not very accurate. However, there are so many products available, and at such little cost, you could buy one fixture of several different brands and test drive them very inexpensively. That's assuming you don't have access to some good retailers who could bring in a few products for you to sample. Once you find the one(s) that suit your needs you'd be good to go. Wiring a bunch of LED products is fairly easy. I don't know the theatrical wiring rules in the UK, but I run 10 - 20 LED pars on one circuit routinely with no issues.

 

[DaveB]

We have a lighting desk (Zero 88 Frog. NOT the fat frog version) but I wasn't sure whether this would support their coloring changing ability?

AFAIK, the basic Frog desk is designed for conventional dimmers, so it won't understand any intelligent features on LED fixtures (strobing, sound activation, macros etc). But as techieman says, you can easily dial in raw colours using your desk faders. It's likely the desk won't handle any control channels (strobing etc) correctly (since it probably treats everything like a dimmer) so you should switch any LED fixtures into a basic "RGB/RGBAW" mode, or avoid patching any DMX control channels into your desk - only patch the RGBAW channels (plus dimmer channel if necessary)

The Frog appears to only have 48 channels of control - not a lot when one RGBAW LED consumes 5 channels. So make sure the fixtures you're purchasing will fit into that restriction.

You don't mention what kind of fixtures you're considering or your budget. But as suggested, make sure you test drive a few first before committing to a big purchase. You may be disappointed by the limited colour range and lack of warmth of certain LED fixtures, especially as you are used to conventional gels. LED fixtures with amber or white LEDS (in addition to RGB) will help you create warmer colours and pastel shades. Of course you could always upgrade gradually, with some new LED fixtures for washes and backlight, and hang onto some traditional fixtures for actor-friendly front light.

 

[gafftaper]

Just found the Frog manual online. Dave is correct that it is limited to only 48 channels. That's going to make it very hard if not impossible to control a bunch of LED PARs. You could set all the PARs on one or two sets of DMX channels. You will lose individual control by doing this but be able to squeeze them in without eating all 48 channels.

How many dimmers do you have?
How many fixtures do you currently have?
How many channels do you typically use?

If you only use like half your channels then you could put the LED's into 3 or 4 groups of channels and be okay.

Does the problem we are pointing out here make sense to you or do you need further explanation about how addressing fixtures and using channels on the Frog works?

 

[BillESC]

This might be a situation where a second controller dedicated to your LED fixtures is warranted.

 

[mozsey]

AFAIK, the basic Frog desk is designed for conventional dimmers, so it won't understand any intelligent features on LED fixtures (strobing, sound activation, macros etc). But as techieman says, you can easily dial in raw colours using your desk faders. It's likely the desk won't handle any control channels (strobing etc) correctly (since it probably treats everything like a dimmer) so you should switch any LED fixtures into a basic "RGB/RGBAW" mode, or avoid patching any DMX control channels into your desk - only patch the RGBAW channels (plus dimmer channel if necessary)

The Frog appears to only have 48 channels of control - not a lot when one RGBAW LED consumes 5 channels. So make sure the fixtures you're purchasing will fit into that restriction.

You don't mention what kind of fixtures you're considering or your budget. But as suggested, make sure you test drive a few first before committing to a big purchase. You may be disappointed by the limited colour range and lack of warmth of certain LED fixtures, especially as you are used to conventional gels. LED fixtures with amber or white LEDS (in addition to RGB) will help you create warmer colours and pastel shades. Of course you could always upgrade gradually, with some new LED fixtures for washes and backlight, and hang onto some traditional fixtures for actor-friendly front light.

If I'm not mistaken, DMX is just a value. It's not like it says, "dimmer and only dimmer" or "this is intelligent." Strobe should still work because it's a value from 1-255 that decides how fast it strobes.

Correct me if I'm wrong, this is just how I understand DMX.

 

[shiben]

I suppose that probably is how it works but you wont get the encoders and the like to run it... Which can be a bit of a pain.

 

[gafftaper]

Bill's right. Ideally you need an entire new console but you may not have the extra cash for that. If you don't plan on a lot of fixtures, an ETC Smartfade ML for around $2500 would probably handle all your needs without breaking the bank. I'm not an expert on the Smartfade ML but I think it can independently control 24 LED fixtures AND still run 48 dimmers.

Somebody please confirm/correct me on that?

Or you could leave your existing console in place and add a cheap one next to the Frog just for the LED's. A Chauvet Obey 70 will independently control 12 LED fixtures for $150. An Elation Show Designer is a little better quality product and has some more features. It can independently controls 16 fixtures for $750. Neither of these is a high end product but they'll do the job.

Stepping up from there, a Strand Basic Palette 2 is the entry level into the real console world. I think they run around $3500... although it's been a few years since I checked. It only can handle 100 channels but you can increase that to around 250 (which should handle your needs) for around $500 more. That's a very nice easy to learn console that will do some really cool stuff controling both your existing gear and new LED's.

From there you get up into the ETC Element/Ion world and the rest of the Strand line. These are going to start around $5k.

You could go cheaper with a PC software solution. There are lots of cheap/free options out there (search here on CB there are lots of articles on this topic). I'm a big fan of buying something that has control handles. It's very frustrating trying to control multiple lights only one mouse click at a time. So if you go this route try for something like Chamsys MagicQ with a small fader wing for around $1k.

Don't go cheap on DMX cable! It may look the same but Mic cable is NOT an alternative you can rely on! Don't underestimate the expense DMX is going to add to the package! You can save money by using CAT 5 (or better) ethernet cable and RJ45 to DMX adapters like these. The adapters are around $13 each (for example $13.25 from production advantage). You need an in and an out for each section so you are looking at $26.50 + the cost of the cat5 cable. So you can make a 10' cable for under $30 with cat 5 and adapters. That's about the same price as a 10' DMX cable. Anything longer than that and you are going to save a lot of money running cat 5 and adapters instead. 100' 5 pin DMX cable is $91 at Production Advantage. Two adapters and a 100' Cat 5e cable from Monoprice will cost you $37. Buy a spool and make your own cables for even less. Also don't forget to buy a DMX terminator at the end of the run.

 

[DaveB]

If I'm not mistaken, DMX is just a value. It's not like it says, "dimmer and only dimmer" or "this is intelligent." Strobe should still work because it's a value from 1-255 that decides how fast it strobes.

Yes, DMX at its lowest level is just a dumb collection of 0-255 numbers. But at the higher level of programming a show, cue stacks and submasters would not behave ideally.

Say you have a simple look (some yellow LEDs strobing @ 4Hz) programmed into a submaster fader. When that submaster is pulled up to any brightness level, you always want a 4Hz strobe.

A simple desk like the Frog can't handle that. It will change every programmed DMX channel as you move the fader, so the yellow will fade in & out (good) but the strobe will speed up & slow down (bad).

A more advanced desk with fixture profiles would understand to snap the strobe channel to 4Hz and keep it there regardless of submaster level.

 

[len]

Programming LED pars is no big deal on any console. You could theoretically use one of these Pocket Console® DMX Wired Models : Baxter Controls, The Pocket Console DMX(tm) and be fine. Most LED pars have different modes, one that is just RGB, and then modes that use additional channels to adjust things like intensity, strobing, color macros and the like. But even so, running them with a 48 channel board is possible. Assuming a 6 channel product, I'd make 4 banks of LED, which would require 24 dmx channels. There'd still be 24 channels for the existing dimmers. Or break it down however. Or, if the Frog had dmx in (I doubt it) get another small console. Elation makes fader boards for like $300. Or get a pc based solution and use the Frog for fader input into that.

As for a specific personality, it's not really necessary. Just use a dimmer pack profile with the same number of channels and keep the fixture manual handy. The fixture doesn't care what the board thinks the fixture is, it only is interested in what dmx values on which channels it is receiving.

Any issues with programming and submasters, HTP, LTP, etc., would be there regardless of whether you were using a specific profile or some generic profile jerry-rigged to the purpose.