# LED v Tungsten

#### Robert F Jarvis

##### Well-Known Member
Mentioning to a tech in anothertheatre I was currently "Gelling" some cycs, he commented on how old fashioned. I'm guessing he was running multicolor fixtures.

According my scant knowledge LEDs produce very narrow emission bands. Looking a spetral scan one would see very narrow red, green and blues popping up around 600, 540 and 480nm without much in between.
This means colors on stage in between these might not get lit correctly e.g. a yellow shirt (580nm). A spectral graph of a tungsten bulb on the other hand has a very wided emission spectra thus lighting a wider range of colored objects.

I know we now have amber and white LEDs and even ones with lime in to help broaden spectra. So my question is: are LEDs ready to completelty replace more conventional tungsten stage lights?

#### DaveySimps

##### CBMod
CB Mods
LED's have come a long way in recent years. I have not seen a theatre install in recent years that include many incandescent fixtures at all. Proper fixtures do really render great color, and are even friendly on skin tones. You do get what you pay for with LED's. In initial cost and conversion to constant power (if retrofitting) is an expense, but the flexibility can be wonderful. ETC ColorSource fixtures are king. That is what I am seeing most of, and what I liked best when I demoed fixtures. There are other that are great too, depending on your exact needs.

~Dave

#### MNicolai

##### Well-Known Member
Fight Leukemia
Agree w/ @DaveySimps. Whatever your impression of LED's is, what you've said is the mentality from a decade ago. You can still find bad/cheap fixtures that will mix to white and it will have that "Digital Nausea" look to them where they are distinctly popping R/G/B but missing all the wavelengths of color in-between. However, the more reputable modern fixtures do a pretty good job at smoothing out the color rendition across the color spectrum.

The primary area where LED's tend to struggle still is brute force output at pastels/white. ETC Series 3 knocks this out of the park but still doesn't quite have the shear output of a 750W Source Four. It is more comparable to a 575W fixture, which is what the vast majority of users are lamping at anyway. In a cyc application where strong colors are most common, this is a non-issue because that's where LEDs' additive color mixing gives stronger output in saturated colors than compared to the subtractive mixing of gels that are so saturated you'll burn them up in no time.

FWIW, many broadcast TV sets are now LED. Not much of the evening news or sports commentary segments are still happening with tungsten. I certainly wouldn't go so far as to say tungsten is dead, but most places that are investing in new fixtures are going LED.

So in general, where you will have trouble is largely if you're buying bargain bin fixtures for quantity-over-quality. Like any other technology, there will premium cutting edge products but those will never fully displace the market for cheap generic products at 1/10th the cost and reliability. Stay with something reputable and you'll be fine.

#### Robert F Jarvis

##### Well-Known Member
Excellent. We are a volunteer, none profit local theater so low/no budget for the better LEDs. But al you said makes sense and If/When  is there I will propose something along the lines of the ETC Series 3. I've heard a grreat deall about them. Thanks for the input. We are always learning.

#### almorton

##### Well-Known Member
It's definitely worth looking at colorsource, especially with the new colorsource V extending the colour gamut. We have original colorsource in our theatre and they're very good and a lot less expensive than the lustr 3 fixtures.

#### Lextech

##### Well-Known Member
If you need punch, Chauvet’s Reve 3 has more then anything else I’ve demoed and the color palette is great.

#### Colin

##### Well-Known Member
^ What they said, and replacing your cyc systems first is a huge benefit to your gel costs and labor, especially if you have far cyc types with a 1K lamp burning through a sheet of deep color in a few performances. Sometimes the big single expense of the upgrade gets help from a grant or donor, and then the gift keeps on giving. Where I am now, when I need to swap my top and bottom far cyc rows it's 36 sheets of gel, close to \$10 each now. Eliminating that cost is a transformative savings for a shoestring budget. I did it at my prior facility, switching (with help from a donor) from Altman Sky/Ground Cycs to ColorSource Cycs and ColorForce strips. That was the first phase of a multi-year upgrade where I swapped one rep plot system at a time, in order of their impact on production budgets and design: cycs, then tops/backs, then booms, then everything else. The "everything else" is perfectly happy being tungsten for as long as it needs to be, and I'd still keep a good stock on hand for now, but I was almost always satisfied using Series 2 Lustr from front angles and the reasons I'd use tungsten were usually about the brightness issue in those warmer pastels and whites. I'd been lamping mostly at 575W before the upgrade, with some 750W lamps available for special uses, but with the big energy savings after the upgrade, I felt okay swapping to primarily 750W, which maximized the advantage of keeping those fixtures around, and also I think helped balance the perceived intensity and "zing" between the tungsten and LED.

#### JChenault

##### Well-Known Member
One note to add. good color rendering needs multiple colors in the fixture.

cycs are usually l white or light blue. Color rendering is not as big a deal on a cyc

ie for front light I want 8 color emitters. For cyc three or four

that said, the standard blue is not very deep. I have a mix between CS deep blue units and Altman spectra cycs. The deep blue blows the spectra cyc out of the water

#### JonCarter

##### Well-Known Member
Since we're on the question of colors from tungsten vs. LED instruments, can someone fill me in on this. I know that the newer LED instruments use multiple LEDs in addition to the original R,G & B. I understand that we now have the addition of at least lime, amber and probably several more. But all of these are narrow bandwidth, and the sum definitely does not look like the continuous spectrum of a tungsten source.

For an LD used to selecting color media (for use on tungsten sources) from his favorite manufacturer's swatch book (Roscoe, Brigham, Lee, Cinemoid, Cinabex or whatever,) how does s/he duplicate the appearance on scenic elements and actors of her/his selected color(s) from a tungsten source when using LED instruments?

Somehow, I can't picture the poor LD spending days or weeks with a board of color swatches from the scenic designer plus an actor or 2 in makeup, and a pair of instruments, one gelled and one LED, tweaking LED colors until they match, then doing it for the next LED instrument, then repeating the process for all of the other selected gels and instruments to be used in the design. Have the LED manufacturers created color profiles for their instruments which match gel colors? If so there must be a lot of profiles out there!

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##### Well-Known Member
Fight Leukemia
The same question could be asked of tungsten vs tungsten with regards to variance from lamp to lamp or deliberate color temperature design. The same piece of gel changes with age. Add a white LED to the mix and the spectrum gets filled in by the phosphor, but white LEDs also vary in output across the spectrum. Gel varies from lot to lot so everything has tolerances, and LDs may be the most tolerant of the bunch.

LED manufacturers and console manufacturers have created color profiles and yes, there are lot of profiles out there, some better than others. I'm most familiar with ETC's attempts at calibration within the fixtures and color picker in the console that offers profiles for several gel vendors overlaid with fixture calibration from multiple fixture vendors.

If you want to get into the weeds on this, hunt up Mike Wood's Protocol articles. He's been covering the topic for decades. Gel Color Pickers - An Exercise in Futility circa 2012 may be the one that comes closest to addressing your question.

#### Malabaristo

##### Well-Known Member
Since we're on the question of colors from tungsten vs. LED instruments, can someone fill me in on this. I know that the newer LED instruments use multiple LEDs in addition to the original R,G & B. I understand that we now have the addition of at least lime, amber and probably several more. But all of these are narrow bandwidth, and the sum definitely does not look like the continuous spectrum of a tungsten source.

One of the really interesting things about the lime/mint and a lot of modern amber LEDs now is that they're not actually narrow-band emitters. They use a phosphor conversion similar to white LEDs to produce a wider spectrum. That's part of why they're such a useful addition to improve overall white and pastel color rendering. There's a whole lot of interesting color theory involved in choosing what mix of LEDs to use in a fixture...

Also, for amber the primary driver was brightness: you can get more light out of PC amber than a traditional amber LED.

As a lighting designer, I find that I don't think about gel colors at all when I'm designing with LEDs. I put everything in direct mode and use the hue/sat wheel to get in the ballpark, then tweak individual colors until I get what I want. This probably isn't true for everyone, but I've gotten quick enough at that where a lot of my final design choices happen in the space with real costumes and scenery in front of me during tech. The ability to do that on the fly and make a wide range of subtle color choices throughout the show without gel swaps vastly outweighs the loss of theoretically perfect fidelity with tungsten + gel (assuming you have decent fixtures to work with...) Also, you're never stuck wanting something between two standard gel colors. If it's in the gamut of the fixture, you just mix it.

#### ship

##### Senior Team Emeritus
Just a quick defence back to the McCandless advantage for debate. Three/four fixtures located in three locations for each color intended, for each position if even using McCandless concept for design; will help to sculpt better than a single dialed in light in a single position. Less fixtures might make placing shadows/scilpting harder.
I know I am old school and there is a beyond McCandless design new concept out there. Not familar with what it is or what book to read in the modern design concept.

#### JChenault

##### Well-Known Member
Somehow, I can't picture the poor LD spending days or weeks with a board of color swatches from the scenic designer plus an actor or 2 in makeup, and a pair of instruments, one gelled and one LED, tweaking LED colors until they match, then doing it for the next LED instrument, then repeating the process for all of the other selected gels and instruments to be used in the design. Have the LED manufacturers created color profiles for their instruments which match gel colors? If so there must be a lot of profiles out there!
actually this is what several broadway, professional designers do. Not with actors in makeup, but they will go to a rental house and create 30 to 50 color palettes of their favorite colors for all the instruments in inventory. When a new fixture arrives that they will be using, they add that fixture to their palette.

#### Lextech

##### Well-Known Member
I actually also make my own pallets, mostly to have different fixtures match each other in certain colors that I rely on. We have a mix of LED, movers and HPL lamped fixtures and even within the same manufacturer, EOS provided colors are not the same. For example I have Batten72s, S-PAR1s and Reve 3s. If I pick, say R80 in the EOS gel picker, I get three different shades of blue and none will match my top cyc lights which are gelled. Do I need every color to match perfectly, no, but some of them it does matter to my eye.

#### MNicolai

##### Well-Known Member
Fight Leukemia
As a lighting designer, I find that I don't think about gel colors at all when I'm designing with LEDs. I put everything in direct mode and use the hue/sat wheel to get in the ballpark, then tweak individual colors until I get what I want.

I found the transition to designing with and programming LED's to be much easier once I threw gel swatch numbers overboard. It's a crutch -- albeit a useful one to some, but very limiting. And when a designer wants Congo Blue, they're used to getting L181 through subtractive mixing at very dim intensity and in most cases with the gel already partially starting to desaturate. With LED's, you can get many times more intensity and you don't have to anticipate the color fading by the third performance. Using gels to determine designs for LED fixtures is like using a trying to drive down the highway with only a small peephole to see through in an otherwise blacked-out windshield.

I also found that older designers were in a habit of asking for "red @ 60%, blue at 30%", etc for cyc lights and such, and then weeding through gel numbers to get LED's to do what they wanted. As a programmer, I had to break some of that habit and just tell them to stop interpreting the programming for me. Just talk to me like an artist and tell me you want something more saturated, more purple, less green, a little darker, etc. Calling out exact levels for every color mix is exhausting and time-consuming. It's like trying to sink a putt uphill where the harder most people try to be technically precise, the farther away they actually land the ball from where they wanted.

#### RickR

##### Well-Known Member
IMHO there is a loss of color range and subtlety with LEDs. But only a few LDs (and no ME or Admins) are willing to trade that for LED benefits; wide color range in each fixture so fewer fixtures needed, no gel fading/replacement, last minute color choices, low heat on stage, simplified power...

#### Derickls

##### Active Member
Just a quick defence back to the McCandless advantage for debate. Three/four fixtures located in three locations for each color intended, for each position if even using McCandless concept for design; will help to sculpt better than a single dialed in light in a single position. Less fixtures might make placing shadows/scilpting harder.
I know I am old school and there is a beyond McCandless design new concept out there. Not familar with what it is or what book to read in the modern design concept.
I would say the less fixtures argument isn't about reducing the number of systems you have in your plot, just the number of fixtures in each system. For example, i no longer need 2 or 3 fixtures next to each other ultimately doing the same thing just will a different color gel.

#### Lextech

##### Well-Known Member
I found the transition to designing with and programming LED's to be much easier once I threw gel swatch numbers overboard. It's a crutch -- albeit a useful one to some, but very limiting.

I use gel numbers as a starting point. I have found certain colors that I know work well with each other and tend to rely on them. So if I want a light pink, I know my starting point in my mind is R33. It is faster for me to hit a button or type @5/33 instead of spinning encoders or a using a color picker. It's my work flow. I tend to have a lot of shows with very compressed time to program and every tool to make things faster is a benefit. If I have time to tweak, I do. You can call it a crutch if you want. My question to you as a programmer is how long is it going to take you to find my medium blue that I want if that is all the information you get at first? How fast can you get to R68 as a starting point? Numbers, to me aren't limiting at all, they are a way to communicate an idea to someone else.

#### RonHebbard

##### Well-Known Member
I use gel numbers as a starting point. I have found certain colors that I know work well with each other and tend to rely on them. So if I want a light pink, I know my starting point in my mind is R33. It is faster for me to hit a button or type @5/33 instead of spinning encoders or a using a color picker. It's my work flow. I tend to have a lot of shows with very compressed time to program and every tool to make things faster is a benefit. If I have time to tweak, I do. You can call it a crutch if you want. My question to you as a programmer is how long is it going to take you to find my medium blue that I want if that is all the information you get at first? How fast can you get to R68 as a starting point? Numbers, to me aren't limiting at all, they are a way to communicate an idea to someone else.

##### Well-Known Member
Fight Leukemia
How fast can you get to R68 as a starting point?
chan at 5/68 enter. How would you like it tweaked? I use numbers to rough something in then deliberately hide the numbers and dial things in with faders, wheels and encoders. Seening the numbers makes me want to round to the nearest 5, which may not be the desired outcome.

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