The theatre I'm working for just bought 18 Elation Design 36 RGB LED fixtures and now that I've done a show with them, I thought I'd share.
In short, they aren't perfect, but I'm happier with them then I thought I'd be. We've got about a 20' throw, and the fixtures claim they have about a 45 degree beam. It is true that most of the light goes out in that beam, there is lots of spillage coming out of the fixture. Any ceilings and walls near the edges of the lens are lit, not well, but more than my pars or ERSs. Not surprisingly, looking only at the back of them, it's much more difficult to see if a particular instrument is on. Almost impossible, actually.
We are using them primarily as wash fixtures, with 6 as a front wash across ~30' stage width. The other 12 are used as side lights with the stage divided into thirds, and two on each side (US and DS). I have noticed very little of the triple color shadow from the difference LED colors. It's there, but either easily washed out by our conventionals or by the other LED fixtures. One of the problems with the space is that it has a low ceiling (~7'-9" to the grid), the stage is long and not very deep and there is about 7' of audience depth to work with. The six front lights provide an incredibly even wash over the stage with only two slight hot spots that probably has to do with the grid layout/instrument placement.
True to form, the instruments don't seem to put our any noticable heat, and they are plenty powerful enough to color the stage and compete intensity wise with the PAR38 instruments that are the primary light source for the space. With all three colors up at full, the instruments put out a slight purplish light. By varying the intensities, I have been able to find colors similar to the Rosco gels I'm using for the conventionals, and I feel reasonably confident that I could get close to simulating a no color blue, or one of the other high transparency gels if I needed to. I was also concerned about simulating the really saturated colors of the swatch book. I think the intensity of the color can be simulated, but the LEDs are just not dark enough to do it.
My one complaint is sort of big deal. The intensity curve on the LEDs is somewhat uneven. At low intensities, there are several thresholds where the individual LEDs jump from one intensity to another in such a way that it is clearly seen. Above about 30% it becomes less noticeable, but below that, it is a rather distracting effect. In fading in an instrument, the LEDs will turn on somewhere between 1%-2% then hold intensity until the DMX signal tells them they should be at about 5%, and the light jumps suddenly in intensity. This irregularity varies with each individual LED within the instrument and from instrument to instrument. It seems to me that it has to do with the fabrication of each LED being a bit different. I have heard that manufacturers make batches of LEDs, then discard the ones that aren't up to snuff. It seems to me that this problem is related to that procedure.
This jumping I have attempted to hide by fading in the LED fixtures (depending on total fade time of the cue) anywhere from 0 seconds to 1 second after the conventionals start fading, and timing it so the two fades end at the same time. Unfortunately, I didn't bias my plot with this in mind (because I wasn't aware of it), so the jumping is still quite noticeable.
It is possible that our control system is at least partially to blame. We're using an old version of Horizon on an old computer, and the refresh rates probably aren't what one might get with a modern dedicated board. However, my impression is that any difference that change would make would not entirely solve the problem.
I am happy with them, and they will add a great deal of much needed versatility to the future plots for that space, but I wish that they had a smoother fade.
In short, they aren't perfect, but I'm happier with them then I thought I'd be. We've got about a 20' throw, and the fixtures claim they have about a 45 degree beam. It is true that most of the light goes out in that beam, there is lots of spillage coming out of the fixture. Any ceilings and walls near the edges of the lens are lit, not well, but more than my pars or ERSs. Not surprisingly, looking only at the back of them, it's much more difficult to see if a particular instrument is on. Almost impossible, actually.
We are using them primarily as wash fixtures, with 6 as a front wash across ~30' stage width. The other 12 are used as side lights with the stage divided into thirds, and two on each side (US and DS). I have noticed very little of the triple color shadow from the difference LED colors. It's there, but either easily washed out by our conventionals or by the other LED fixtures. One of the problems with the space is that it has a low ceiling (~7'-9" to the grid), the stage is long and not very deep and there is about 7' of audience depth to work with. The six front lights provide an incredibly even wash over the stage with only two slight hot spots that probably has to do with the grid layout/instrument placement.
True to form, the instruments don't seem to put our any noticable heat, and they are plenty powerful enough to color the stage and compete intensity wise with the PAR38 instruments that are the primary light source for the space. With all three colors up at full, the instruments put out a slight purplish light. By varying the intensities, I have been able to find colors similar to the Rosco gels I'm using for the conventionals, and I feel reasonably confident that I could get close to simulating a no color blue, or one of the other high transparency gels if I needed to. I was also concerned about simulating the really saturated colors of the swatch book. I think the intensity of the color can be simulated, but the LEDs are just not dark enough to do it.
My one complaint is sort of big deal. The intensity curve on the LEDs is somewhat uneven. At low intensities, there are several thresholds where the individual LEDs jump from one intensity to another in such a way that it is clearly seen. Above about 30% it becomes less noticeable, but below that, it is a rather distracting effect. In fading in an instrument, the LEDs will turn on somewhere between 1%-2% then hold intensity until the DMX signal tells them they should be at about 5%, and the light jumps suddenly in intensity. This irregularity varies with each individual LED within the instrument and from instrument to instrument. It seems to me that it has to do with the fabrication of each LED being a bit different. I have heard that manufacturers make batches of LEDs, then discard the ones that aren't up to snuff. It seems to me that this problem is related to that procedure.
This jumping I have attempted to hide by fading in the LED fixtures (depending on total fade time of the cue) anywhere from 0 seconds to 1 second after the conventionals start fading, and timing it so the two fades end at the same time. Unfortunately, I didn't bias my plot with this in mind (because I wasn't aware of it), so the jumping is still quite noticeable.
It is possible that our control system is at least partially to blame. We're using an old version of Horizon on an old computer, and the refresh rates probably aren't what one might get with a modern dedicated board. However, my impression is that any difference that change would make would not entirely solve the problem.
I am happy with them, and they will add a great deal of much needed versatility to the future plots for that space, but I wish that they had a smoother fade.
