Conventional Fixtures - LEDs for the theatre

[Kelite]

So I asked myself the other day, "Why don't we see a few white LED PARs or battens offered to the theater crowd?"

Realizing the need for a full spectrum of color for gels to actually look like they are supposed to- who would be interested in these fixtures?


Let the games begin!

[Grog12]

Originally Posted by Kelite

So I asked myself the other day, "Why don't we see a few white LED PARs or battens offered to the theater crowd?"

Realizing the need for a full spectrum of color for gels to actually look like they are supposed to- who would be interested in these fixtures?


Let the games begin!

.....Wouldn't this be kind of contradictory to LED's being a "green" light? I mean kind of the draw of a LED PAR or ERS ect, to me at least, is A) Not having to replace lamps, B) Color mixing and not having to buy gel.

[Kelite]

< A) Not having to replace lamps, B) Color mixing and not having to buy gel.>


Yes, absolutely right. The replacement issue would save plenty of time, risk, and lamps themselves. Do you find the current theatrical offering of RGB LED's able to reproduce the gel colors you've grown accustomed to?

Wouldn't it be easier to use your favorite gel in the frame of the white light LED?

[porkchop]

In a house here in Wyoming there's LED mood lighting all throughout the house and the selling point on it and why it was actually installed (IMHO of course) was because the LD could go you know I think the house needs to be a soft blue for this show, and a few keystrokes later it changes from whatever color it was to blue. If they want to make slight changes no reordering or regelling necessary it can all be accomplished quickly and easily from the board (or a nearby computer in this case).

I could see the need for white LED fixtures if they are going to be used with glass gobos, or if you are going to try and use the conventional type of CMY color mixing used in most automated fixtures today that involves diachroic filters (they are diachroic right, that's what I've always called em).

I think the gobo option is a likely one that we'll see eventually in some kind of LED ERS type fixture. The filtered color mixing only make sense to me in a single white LED source intelligent fixture and I guess it is a possibility and in theory could give you more consistent lumens throughout the color range. But as for now I think that since color mixing is already easily accomplished through RGB (and sometimes A or W too) arrays of LEDs in the fixture that it is unnecessary until we have very good very bright white LEDs.

AFTER THOUGHT:
Kelite, after reading your second post (posted between the time I started this and posted it the first time) that actually does make a good bit of sense. To my knowledge white LEDs aren't actually able to produce the full color spectrum that an incandescent lamp does, but if it could my limited experiance with LED fixtures tells me that gel would last a whole lot longer as I don't think it would produce as much heat at the gel. I would file this in the some day file though because I really don't think that LED fixtures are cheap enough to make viable for that purpose. I think the upfront cost (including the R & D for the full spectrum white LED) vs a conventional PAR or Fresnel would more or less nullify the overall savings of virtually no lamp replacement. That cost statement has no statistical backing, but if I was wrong I think we would have seen a fixture of this type.

[Grog12]

Originally Posted by Kelite

< A) Not having to replace lamps, B) Color mixing and not having to buy gel.>


Yes, absolutely right. The replacement issue would save plenty of time, risk, and lamps themselves. Do you find the current theatrical offering of RGB LED's able to reproduce the gel colors you've grown accustomed to?

Wouldn't it be easier to use your favorite gel in the frame of the white light LED?

I don't find the current offering of LED's worth the price.

See that's the other thing...would this white LED A) Be punchy enough to compete with its incandescent bretheren and B) Be cost efficent up front and in the long run?

[gafftaper]

I'm brainstorming 10 years+ down the road here so nobody freak out on me. Let's assume that technology is able to create a true white LED source eventually. It's not there yet but there's no reason they can't figure out a way to do it... perhaps through an additive combination.

Then we could have a new LED Gel line that is tuned for LED's. I suppose it wouldn't work as each LED manufacturer has a slightly different color spectrum.
From there it seems like we would need a new USITT Standard for what is a "white LED". Then you guys could make Gel to match. The biggest problem for Apollo is that LD's will die of old age before the gel needs replacing.

[Kelite]

Originally Posted by gafftaper

The biggest problem for Apollo is that LD's will die of old age before the gel needs replacing.

Wow! If that's my biggest problem, I've got it made!

But seriously, the calibration of true white LEDs would have to be pretty consistant to allow general use. Assuming all challenges are solved and pricing continues to drop- would the energy savings cause more theaters to look seriously at LED use?

[Ross]

I recently was looking to replace my altman sky CYCs with an LED inventory, mainly as a long run cost saver but the cost per instrument is still too high and I believe that many LDs would want to suppliment the LEDs with the sky CYCs because of the limited mix range. Also, especially in those with only RGB (no A or W) the amber mixing is really lacking in my opinion.

[derekleffew]

Originally Posted by Kelite

So I asked myself the other day, "Why don't we see a few white LED PARs or battens offered to the theater crowd?"

Realizing the need for a full spectrum of color for gels to actually look like they are supposed to- who would be interested in these fixtures?...

The five-hundred year-old practice of depositing colored light on the stage via subtractive filters is inherently wasteful and inefficient, and will not/can not continue much longer. At some point sooner rather than later, Apollo Gel, Roscolux, Lee, and GAM will go the way of Brigham and Roscolene. Additive mixing may be the answer, but I suspect new light sources and fixtures, which haven't been developed yet will be the true panacea. Imagine sitting at the lighting desk, and typing in the nanometers of the color you want, the amount of lumens you want on the stage, and the size of the pool desired. Yes, all of this can somewhat happen now, but there are better ways of achieving the desired results--they just haven't been invented yet.

Sorry Keith, I find it short-sighted of you to even consider putting gel on an LED source--big step backwards. A forward step is to look at a fixture such as the CK IW ColorBlast 12, which has both "warm" and a "cool" sets of LEDs, and allows the user to select any desired color temperature from 3000K-6500K. I'm surprised no other manufacturer has yet to take up this idea and put it into a more familiar form factor, such as a PAR housing.

I also take exception to your phrase "for gels to actually look like they are supposed to-". Who's to say what gels are supposed to look like? Today's designers are quite adept at mixing T/H and Arc sources and balancing them with the wide range of color correction filters offered. It's ironic that in the old days we were told RGB rondels or gels did not mix to white because theatre filters were not "pure" enough. Now we have trouble because RGB LEDs are too "spiky," emitting only a narrow band of their portion of the visible spectrum. And so the RGBA, or Selador's R/RO/A/G/C/B/I X7 fixtures.

Many, as yet undeveloped, light sources are on the way, which I predict will invalidate the need for both subtractive and additive color mixing systems.

Oh, also. Gobos: on their way toward obsolence. Buy stock in Blue Pony. However, gafftaper and gafftapegreenia should be happy to hear that gaffer's tape will always be necessary, until we get that wireless power thing worked out.

[Grog12]

Originally Posted by gafftaper

I'm brainstorming 10 years+ down the road here so nobody freak out on me. Let's assume that technology is able to create a true white LED source eventually. It's not there yet but there's no reason they can't figure out a way to do it... perhaps through an additive combination.

At that point, especially if they got there through additive combination, you wouldn't need gel. If the light can additivly mix to white, why not spend the time to make it a full RGB/CMY (however they get there) instrument that color mixes on its own.

Not to hate on Apollo, Rosco and the others, LED's when they reach their hay-day, are cost effective, and are saturating the market there's not going to be a need for gel. Designers will have the option of mixing their favorite color on-board on the instrument.

Currently we have lights that do this...just not very well. While the development of a "true white" LED will be a great stepping stone I think research into a flexible fixture is the better road to travel.