Friday, October 11, 2013

To LED or not LED

Ahhh... LEDs.  The really snazzy new lights that everybody wants to add to their hang.  LEDs are cool and awesome, right?

Yes and no.  As a designer I must admit that I am divided when talking about LEDs.  I love the color output.  You cannot believe how lovely these things are when they start scrolling through colors.  They pretty much blow conventional lights away when it comes to color.  We did a shoot out with the Source Four LED ellipsoidal and a regular Source Four ellipsoidal gelled with Rosco 27 (a deep, dark red).  To make the outputs match we had to pull the LED fixture back to about 40% output.  Gel works by filtering out part of the visible spectrum.  That means that gel is blocking light output.  If you will look in your handy dandy gel swatch book somewhere there will be a transmission number.  For Rosco 27 (that deep, dark red), transmission is 4%.  That means that 4% of the light generated will make it through that gel.  Not a lot, huh?  With LEDs you can match the color and still get 100% of the intensity output.  It is bright enough to make your eyes hurt.  What is not to love?  For a designer, the color of LED fixtures is the biggest selling point.

A Source Four LED ellipsoidal with a gobo

There are, of course, other things to love.  LEDs don't generate the heat that conventional lights do.  Your actors will love you for that and your HVAC costs will go down.  LEDs pull nominal power compared to a conventional light.  If you assume that most of your conventional lights pull at least 575-1000 watts, an LED pulling 80-140 watts is pretty fantastic power savings.  To make life even better, instead of hanging a three color down wash, you hang one set of fixtures that can be any color you want.  Your hang and focus costs are cut by two thirds.  Again I say, what's not to love?

Well.... there are still a few downsides to the LED.  The industry is working on the kinks and most of these babies are tons better than they were even two years ago.  But there are still flaws to keep in mind before you go crazy and throw out all your conventional lights.

My biggest gripe as a designer is the dimming curve.  LEDs have a different dimming curve than conventional lights.  We expect lights to fade evenly to zero percent when we tell them to fade out.  For the lower end and some mid-range LED products the curve is still problematic.  They fade to 1% or even a half percent and then they click off.  While small, it is still noticeable and, quite frankly, annoying.  I find it to be distracting both as a designer and as an audience member.  The higher end LEDs don't do this.  With LED fixtures you totally get what you pay for.  A $2500 light will just work better than an $800 light.  The $800 lights aren't horrible.  They just aren't as smooth as the $2500 lights.  

Which brings up problem number two- cost.  LEDs are substantially more expensive than conventional lights.  Are they worth it?  If you put in a good fixture they are definitely worth it in the long run.  You will save both time and energy.  The cheap LEDs will probably be more hassle than they are worth.  The exception there would be in special effects LEDs.  American DJ is making some interesting special effects that aren't horribly expensive and that work fairly well.  They have the best water effect I have seen in a while and it is super easy to use.  Plus it really truly looks like moving water.  You can also use it for a pretty easy fire effect.  Very nice.

Problem three is control.  You need a fairly smart console to run LEDs.  An old slider board or two scene preset isn't going to be enough.  Unlike conventional lights that just use one address, LEDs take multiple addresses.  The newer, nicer consoles see LEDs as one channel with multiple attributes or parameters.  Older consoles will see each attribute as a channel and thus a slider.  The LEDs will eat up your channel space.  If you are just using a few LEDs you possibly can limp by with your old console.  You would be better served to plan to upgrade your console when you purchase an LED package.

ETC Ion console in action

The last thing to keep in mind when contemplating an LED addition is that it is not a conventional light.  It is an entirely different type of fixture.  It’s not bad.  It’s just different.  The majority of LEDs are wash fixtures, but they are not fresnels or PARs and they don’t work like an incandescent source.  Unless you are going with one of the higher end units you can expect there to be more spill light than you are used to with a fresnel.  They just are not as controlled as a single source filament fixture.


So are LEDs worth dealing with?  Certainly so.  Technology is growing by leaps and bounds.  It seems like every day a new fixture is coming out that is bigger, better, stronger and cheaper.  We now have LED wash fixtures, LED ellipsoidals, LED zooms and even LED moving lights.  Eventually, the incandescent will go the way of gaslight and candles and we will all be using 100% LED rigs.   Won’t it be pretty?

 Live on the Green, an all LED concert rig

Live on the Green, an all LED concert rig


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