LED Lighting in Today’s Museums: Scott Rosenfeld

-Music- -Applause- Good morning and welcome to the DW Reynolds center for American Art and Portraiture. Home to both the Smithsonian American Art Museum and the National Portrait Gallery. My name is Tiarna Doherty and I am the Chief of Conservation for the Lunder Conservation Center. Which is a visible conservation facility located on the top floors of this museum. Today’s Lunder conservation centers program has been made possible by the generous endowment that was started by the Lunder family. I proposed to organize a program around light-emitting diodes using museums for a number of reasons. The topic is one of interest to many museum professionals and different departments. We’re also at a moment where we’re not only able to reflect on reasearch that’s been done, but on years of practical experience. We have speakers today, and colleagues here in the audience who have about eight years experience working with LEDs, researching them and implementing them into the design of their museums. In my previous position at the Getty Museum, I was familiar with Jim Druzik’s contributions to LED research. When I arrived here at The Smithsonian American Art Museum in 2011, I became familiar with the work of Scott Rosenfeld, our lighting designer. And his collaborative efforts with not only Jim, but Naomi Miller from the Department of Energy. Therefore, it seemed only natural that our Lunder program on LEDs should begin with presentations from this group of colleagues. Some of the presentations in today’s program will be posted as a webcast in the near future. In addition, we’re very grateful to a group of colleagues here today, who have volunteered to work with Chris Wayner, our Program Coordinator, to write up summaries of the information being presented. These summaries will be posted on our website. And we hope they’ll be published in some form through some conservation professional news letters. Again, in the future. We’d like to thank members of the committee on sustainable conservation practice who are doing this for us, including Mary Coughlin, Sarah Nunberg, Robin O’Hearn, Jia-Sun TSang, and Betsy Haude. And guest contributor Patricia Silence for offering to write up these summaries. For today’s program, we’ve provided the silver folders that you’re holding. And they include a map that Scott Rosenfeld and intern Molly Trask made of the galleries and spaces throughout this building where LEDs have been installed. It also includes spaces like our museum gift shop. The map will also guide you to a multi-purpose room that’s located on the entrance level where you came in for this afternoon, Where Scott Rosenfeld has set up some demonstrations that will be open at 3pm. I had the chance to preview them yesterday and they’re really beautiful. Scott’s taken a lot of time to demonstrate different lighting conditions. In addition, there’s some practical information such as a restaurant list which will help you at lunchtime. We will be having a coffee break and that’s going to be again on the same level you entered the museum in our big courtyard space. And there will be staff helping guide you to that location. We’ve also provided a comment card that I just want to bring to your attention, now. We’d be very grateful if you would fill it out and at the end of today’s program, we’ll be collecting them at the doors. And we take these comment cards very seriously. We welcome suggestions for programming of any sort. Our professional programs can include lectures or symposium. Symposia and conferences. At this point I would like to thank Chris Wayner, whom I hope a lot of you have had the chance to meet. He is our Program Coordinator who has organized today’s even and taken care of so many details. Including registering all of you. This program has proven to be very popular and we are delighted that you have come to join us. We have guests here from Europe and I know a number from California. Chris and I would like to acknowledge a number of individuals who helped us today including Ali Jessing, Susan Edwards, Georgina Goodlander, Scott Rosenfeld, Taylor Blocker, Leah Bright and Gabby Irving. In addition, members of the Lunder Conservation Center are helping today and will be encouraging you to return to the auditorium after coffee. Before we begin our program I’d like to mention that bathrooms are located outside of the auditorium in the lobby, here. And in the event of an emergency you can exit the building the same way you came in or one of the staff will help guide you through the back of the stage. No food or drink of any kind is permitted in the auditorium and we need to be strict about that. And at this point I’d like to ask you to silence your cellphones. We actually have really good Wi-Fi in here so you will get phone calls and emails. They are hard to escape. So, without further ado we’ll prepare to begin. Our first speaker this morning is my colleague Scott Rosenfeld. Scott is the lighting designer at the American Art Museum and Renwick Gallery. Since starting at the Walters Art Museum over 20 years ago, Scott has designed lighting so museum collections can be better seen, experienced and preserved. The advent of energy-efficient LED lighting has led Scott to research new possibilities for manipulating the spectrum of light, to enhance vision and slow the degradation of light sensitive materials. Scott’s next big project is to work with Tom Gallagher and architects from WRL to renovate our Renwick Gallery with 100-percent LED lighting. Scott is chair of the IESNA Museum and Art Gallery committee. And Scott is the 2012 recepient of the Smithsonian’s innovation Spirit Award. Scott. -Applause- Good morning. Thank you, Tiarna. And I was so excited when Tiarna came and said we want to host a conference. And she had asked me to speak and I thought I knew what I wanted to speak about. This is gonna be great. I want to speak how to change a lightbulb. We’d already had really good success working with the Department of Energy. We had exhibits already reinstalled with retro Fidelity’s and retrofitting LEDS is pretty simple. You just take one of these lamps and you unscrew it and it actually goes like this. Yeah, there you go. And you just screw in another lightblub. So, that’s retrofitting it’s a pretty simple retrofitting process. And it had gone fabulously we had several galleries installed and our curators were happy. Conservation was quite pleased, Our Director, Our director for years have been asking us to find more energy solutions. And finally, we could offer something and they were very pleased with the quality. And again, the Secretary of the Smithsonian, the head of the Smithsonian had recognized this was a valuable effort. And everything looked like it was going to be easy and I just had to give you some ideas about how we do that. And then we sent some lamps out for testing and we put new light bulbs in. If we never sent lamps out for testing, we may never have noticed that the color was slowly changing. And the color we so carefully chose to begin with was different. Not necessarily, worse but different and not what we had originally chosen. So, I’m going to re-title this talk a little bit. So now it is The Agony and Ecstasy of LED lighting. Because after thinking about this and, I’ve been grappling with this issue of color change for a few months now. And, after coming, I’m not through it, but I’m working my way through it. I’m still convinced LEDs still provide great opportunities for museums. But, increased complexities and unknowns and when you’re in the place of and when you’re in the place of unknown or lighting designer and you’re not quite sure that, that specification for that product is going to be bulletproof and do everything that it says it’s going be. That’s agonizing. That’s a hard choice to make. For museums that aren’t currently happy with your lighting and you’re using an incandescent, you’re going to find this transition especially difficult. And that’s a lot of what I’m going to be talking about today is how you manipulate any kind of light. Whether it’s LED or incandescent and let’s start with LED. I wasn’t actually going to talk about this but I smashed a lightbulb the other day just to see what inside and it was so cool. I wanted to show you. So, this used to be a regular a-lamp that would throw light everywhere. And what I did was we smashed the front of it and we ended up with blue LEDs and a yellow phosphor disc. So you turn the blue LEDs on and I turned blue and you can see the phosphor disc is right there glowing. We bring that phosphor disc closer and it starts to glow as it receives enough energy from the blue LEDS. We totally cover the blue LED and now we’ve got white light. This process is basically the process for all interior white phosphor LEDs. Everything that you see on my test bed, and I’ve been testing a lot of LEDS, work using this principle. If you’re looking at the L prize lamp or these other phillips lamps. That’s remote phosphor technology. If you’re familiar with Satco it basically works in a slightly different way but similar to what I just showed you. These are what I’m calling chip one board LEDs. They’re taking the phosphor and they’re putting it close to the LED in a completely different way. But it’s the same principle about how we’re making light. Tiarna talked about how these presentations or several of these presentations will be available through the Lunder site. This is my own personal resources. So if you go to this website that will take you to a form we ask you to fill out and that form will send you a link. That link will send you to my dropbox and in that dropbox you’re going to find a few things. The way I just talked about creating light some people have questions about how you can make light this way and have it be high-quality. The way that I learned is by looking at vision calculators. They were very generously offered to this community by NIST. So, it’s the CQS calculator and it’s complicated to use, both calculators in this folder are, but it’s worth it to really understand how we see color. The SSL guidelines for museums is a great document written by Jim Druzik and Stefan Michalski. It’s a fat booklet but it gives you a lot of details about how to select products. The take away from both that and this talk is warranty, warranty, warranty. The department of energy has two great documents on both written by Naomi Miller. So, they are readable. We can actually make our way through these and learn a lot about design and conservation. The one for American art which, I’ll be going through today, is largely about design and from the Getty it’s more about conservation. And lastly, there’s been a lot of confusion about the damaging effects of light, of spectrum and Steve Weintraub wrote a, again a very well- written easy to read article that traces the history about how we calculate those energies and the standard museum practice. There we go. That’s what we use is lighting designers. These are the most common lighting sources for interior architecture Thankfully, there are not very many of them so it’s easy to get your head around. And they are all good in the right application. So, it’s a matter of matching the lighting source to the application. Of a few interesting things, it is important to remember that halogen is a subset of incandescent. I don’t distinguish them, particularly. I mix them, readily. They’re slightly different colors and I account for that. Fluorescent I don’t use much in the museum. It’s a little soft. It’s a little glarey. It’s got its applications but not in many of my designs. HID was actually an emerging technology which may have overtaken LED, but I think LED is a better lighting source for museums. It’s still used and i’m interested in using it for especially long throw applications where LED is not the best source. Then there’s LED and in my vote for 20 years in museums, I was actually locked into incandescent beacause of it’s properties. And LEDs the first time that I can take everything that I love about lighting, the way I like working with light. And use an emerging technology to accomplish all of my goals. Oh and then there’s, I talked about agony and ecstasy, we got that the agony was the color change. The ecstasy is tremendous energy savings 75% and 80%. Just on electricity alone by changing those lightbulbs. Managing humidity and temperature is enormously complicated in our museums. We can reduce HVAC costs by 25%. There’s a lot of benefit and and ecstasy to be had by grappling with the complexities of this emerging and disruptive technology. This is how I asses light. I was 17 years old in a theater class learning about light. This was the first thing I learned. I might ask how many people have actually heard of these qualities before, described in this way? I’m just curious. A smattering. They’re analogous to Aristotle’s poetics of drama. They’re analogous to the elements of design. This is what I control as a lighting designer and if I want to talk about lighting especially, this is what I talk about. So we can understand better that when we open eyes and see something, what is it that’s really providing that vision? So, let’s say you’re looking at me because well you’re looking at me anyway. I’m gonna go through these list twice, once now and once throughout the presentation. So, there’s a certain intensity of light hitting me and it’s feeling pretty bright. Movement. Does the light move? These lights are pretty static. The place that we see movement most often museum I would say is daylight. Just solar path through the day and how it changes through the seasons. there’s various angles of light There’s this light from the front which is kind of filling my face and allowing you to see me clearly. And there’s two lights behind me that are providing definition on my shoulders. This is pretty good lighting. I’ve done a lot of presentations and normally I’ve got this weird fluorescent blob of light to do this with. There’s distribution of light. All these lights have shutters so we can really carefully manipulate the light and shutter it down So, I’ve heard the secret of lighting design is to put the light where you want it and take it away where you don’t. All of that is about distribution and then there’s color. Things are changing and the colors just changed. This is incandescent so it dimmed down and got a little bit more yellow. But we have a variety of colors on one side is a little bit cool, the other side a little warm from the angles behind me. And the front of me is already warm. So, you can start to see deeper by looking at these qualities. I’ve heard it said that until you know how to control something, you may not even see it. And figuring out where we have agency in a situation, will allow so many more benefits and opportunities. This is a place I wanted to start and just briefly because it’s so important what we do and I think sometimes misunderstood. This explains the four factors of photochemical damage. Which is you have to assess how sensitive material is, choose an illuminance value and choose and exposure. How long to leave it on vie.w The last column exposure is probably where we can get some of the most benefit for both energy savings and damage Turning the lights off when people aren’t in the room is the best thing we can do to save energy and save our collections. When we renovate the Renwick we’re talking about adding occupancy sensors. At the Smithsonian we’ve got pretty steady visitorship through the day. So we may not, or we will not use those occupancy sensor through the day, but before hours when our cleaning staff is in? We can save three hours. We can reduce three hours of damage a day, or two hours. Just by adding occupancy sensors. For museums that have sawtooth vistorship unlike the Smithsonian, where they’ve got a lot of kids in the morning, then no-one, a few people at lunch and then no-one and then some people at the end of the day. Occupancy sensors can dramatically extend the life of our collections. I don’t know a better way to do it. Illuminance this is as what Gary Thompson says is the realm of controversy. This determining how much you want to see of the object and balancing that with preservation and that’s the trick. And these numbers are variable depending on who picks them out. But what is interesting is whether it’s a highly sensitive object or moderately sensitive, it’s the same illuminance values. We use the smallest illuminance values for those materials os we can really experience the objects. The fourth column that you don’t see is spectrum and that’s something that museums have typically not used as an assessment with this calculations. And there’s pretty good evidence that for a broad range of museum materials that, not all, but a lot, all of the LEDs that I’m putting in my museum are slightly lower damage potential than incandescent. That’s not for specific object that’s for the Museum as an aggregate. That does not mean these numbers go up no matter what numbers you choose to put there. These numbers are based on what are the smallest quantities we choose as a community to see these materials. And it’s very important to note that at the most sensitive levels, at that 50 to 75 lux or that 30 lux, whatever number you pick, does not protect the materials. At 50 lux, our most sensitive materials will fade, six months, does that sound about right? For my conservation community, less? we It’s hard to know but it’s very, very fast So, we’re talking about intensity. Having low illuminance values makes museums a particularly good application because heat is the enemy of LEDs. The lower the wattage the lower the heat. We’re using a par 30 scale fixture at this height. Worked great. We actually had headroom and added screens, added screens. My next generation of LEDS I chose, I chose twelve lots, more closely than I can match the illuminance to the application. The longer my LEDs will last. And the more energy-efficient. Higher ceiling 22 foot ceiling, I’ve increased the scale of my fixture to par 38. Again, saving 75% of the energy on these retro fits. I retrofitted all the lamps in this gallery. You see this great piece by Beth Lipman. I love this piece. So, what she did was, it’s about excess. It’s about having too much. She has the whole glassblowing community of Sheboygan, Wisconsin to help her craft these pieces. And when she asked me to light it, she wanted me to make it as bright as possible. She wanted this thing to glisten. The only time in my career that i just put up lights until I ran out of power was on this piece. So, you’re seeing an incandescent version now and with the magic of power point, there you go. Twenty percent brighter, 75% energy reduction. Working with the Department of Energy, I can’t express enough gratitude. The goal of our project was to find good applications in the museum for LED lighting. Because LEDs are so directional it seemed like a really good place to apply LED lighting, but we wanted to beyond that. We wanted to see if we could push LEDs beyond where they currently were to challenge the research and development community. And this has been a hallmark of the Department of Energy’s guidance to highlight the good applications, while continuing to press to do better and better; better color, better energy efficiency. And this is an example of where we had mixed results. 30% of this gallery was able to be retrofitted with LED, everything up to a 120 watts. My 250 watt incandescent floods we couldn’t couldn’t get there with LED, then. And actually, I don’t have any good products off the top of my head. Right now, we’re looking to renovate this gallery and HID is actually my best choice, right now. This was bizarrely enough our Waterloo, an eight foot ceiling. This is a different fixture, this is a MR16 fixture. MR16 fixtures, a little tiny and packing all that electronics and all that heat in such a little package was a bigger challenge, than, at the time two years ago, I thought LEDs were up to. There may be good products now and when we talk about flicker we’re talking about another quality. So, this is movement and I think we’re kind of evolutionary, predisposed to movement. You see a tiger in the grass you can see the tiger stripes moving and after it starts moving, you can see it. So, flicker we are particularly attuned to. This is what we call a flicker checker. I’m not going to be mentioning manufacturers names today, with the exception of rare exception of Sylvania. Because, they went through extraordinary efforts to get flicker checkers here today. Those trains, planes and automobiles and if you go up to the demonstration room after the presentations, we will have one for each one of the participants, thanks to Sylvania. It’s a little top, you spin it and if you see this little hex pattern, you’ve got flicker. This was originally developed to get rid of magnetic fluorescent transformers, ballasts. And it will let you know that, hey you have to retrofit your fluorescent technology, magnetic techology to electronic. And it works great and certainly gives a certain confidence to Sylvania products. So some of these MR16’s flicker. Some of them don’t. I don’t know if the current generation of Sylvania MR16’s flicker. I do know that the previous generation would flicker under an electronic ballast but not under a magnetic ballast. And this was a little trick that a lot of designers used, was they’d put a magnetic ballast with all their MR16’s. I can tell you now that sometimes that works, sometimes it doesn’t and it really takes quite a bit of testing to figure out how to work with these technologies. This is the Lincoln gallery with cable lighting and magnetic transformers. And I’m really looking for a solution that I feel confident enough to install in these galleries. This is our great courtyard designed by George Sexton and Associates. Where the lighting design was, it’s a Norman Foster architecture with Kathryn Gustafson doing the landscape architecture. For Sexton and Associates put MR16’s at 65 feet but we all did, I agreed to it, knowing how difficult it would be to change those lamps. It looks beautiful, you get this little star-lit quality and it provides good light. And I would think this would be a good application to install LEDs, they’re going to last longer. And I thought about it and I started researching it and I backed away from that when I didn’t see MR16s exhibiting this, but other retrofit lamps would start they call a catastrophic failure. I hate that word. When an LED burns out, it’s pretty rare but it has certainly happened. Sometimes instead of just burning out, they flash on and off. And if i have an little incandescent light burn out, It’s kind of a bummer, no big deal. If I had a light flashing on and off for a year before I could change it, that would be a deal breaker. We’re moving along, we’re up to angle. This is the only one of the five qualities which is about where you put the light rather than about the lighting source itself. This is a very typical application. The building that we’re in was, originially the old patent office. It was built as kind of nineteenth-century office building and you see this long corridor. It’s all there throughout the museum. If any of these lights were pointed toward you, you’d see that as direct glare. Almost all the lights are aimed perpendicular, straight at the wall. The choice of angle, we still have a few choices, allows you to reveal the sculptures three-dimensional, will determine how the frame shadow falls, the head shadow of the visitor falls. All this is the choice of angle. It will determine reflected glare or something called veiling reflections. On this artwork, the Lansdowne Portrait. It’s important that this is a Portrait Gallery piece. We are two museums that are completely separate. It’s 2 musesums that are completely separate I work for the Smithsonian American Art Museum and there’s The National Portrait Gallery. And we have two different staffs. This was originally hung in front of a bright window which where you’re getting that glare. A lot of people think if you see glare, it’s from the track lights. That’s a miss attribution and that’s one of the things I like so much about these five qualities; how to identify what those problems are. There’s also glare from above. As soon as you get something above your head, there’s inevitably glare. The Portrait Gallery has their own lighting designer and after many hours of work, the reinstalled it. After we actually closed for renovation and reinstalled it, and didn’t put it in front of a window, and with good lighting design there is very minimal glare. And I was saying Alexander Cooper is the lighting designer of Portrait Gallery, and he is considering LEDs. So far like other people in our design community, he has been much slower to adopt. He has been doing testing and he expects to do a gallery pretty soon. And that’s the way I urge most museums that haven’t started to proceed. Start with a gallery. Start somewhere and my experience is once you start somewhere and you start doing a gallery, you see that you can deal with these various complexities and you’ll want to do more for all of the benefits. These are qualities of light. This isn’t about good and bad, this is about determining what’s good and bad because you’ve got a full understanding of light. This is a great arts and crafts piece in my collection, American Art, by William Fosdick. Arts and crafts, so it’s wood with gold. I’m choosing the lowest angle I can to make this as reflective as possible using the smallest quantities of light. Another piece by Jocelyn Chateauvert at the Renwick. This is an artist installation where she put the artwork actually inside of her fiber. They were hers to damage. If you actually look over here still see another installation where she’s got an opaque backdrop with a scrim like material. She was very specific. She wanted the light between these two layers. It’s beautiful. Almost all the light you’re seeing as, seeing through, just a little bit of front light to get that red. So, mixing of angles. We purchased this piece, we reinstalled it. We did not have the opportunity to light it like she had originally wanted. And this is what it looks like. This is all incandescent options. And that’s important to know that I’m about controlling light. I don’t care what the lighting source is. I’m not particularly in the pocket of LEDs. I am right now most enthusiastic about LEDs because I think it’s the best source for museum applications, despite the complexities. but it’s not it’s not quite the same. But certainly worth seeing and seeing the craft of what this artist is offering. I want to take one photograph the flattest angle is if you put a light source next to your eyes like a camera flash and that’s what you get. We’re up to distribution, this is about painting with light, choosing one light at a time. Is it a spotlight, is it a floodlight, how to use these lights together a a system. This is a Western quilt exhibit and it’s work light, glary, work light at about fifty lux, the factor is roughly ten, give or take So it’s about five foot candles that’s the conversion. So, after a lot of work, designers coming in hanging lights very specifically, put the tripod in the same place, place and now we’ve focused the light, put the light where we want it and take it away where we don’t. This now has to be maintained and I owe an enormous debt of gratitude to our facilities management team, who everyday are in the galleries changing lights, lights and putting them back where they belong. This is enormously difficult and especially with incandescent systems that are burning out two or three times a year. It’s well, between one and two times a year is probably fair. It takes a tremendous amount of maintenance and this crew is there day after day making it happen. By transitioning to LEDs we do two things, we can reduce our labor costs by having two people in this building changing lamps every day to maybe, it’s an hour a day. And then every cycle, yet to be determined, we’ll have to do a group re-lamping of all of those 23 we’ll have to do a groupie lamping of all of those lamps. In 2, 3 years, I’m guessing. The other thing is I figured that if a visitor comes into a museum that may be the only time the see our collection. If a lamp is out they’re never going to see it. So, we have one shot and LEDs despite their problems, are much more reliable at staying lit. These are the choices we have and as a lighting designer I have basically been guided in my choice of lighting source by distribution. What allows me the most control and these are the two big segments that we’re choosing between right now within the lighting design community. We’ve got retrofit lamps which fit into our canisters. It took a long time to develop canisters that were low glare, that had good cross baffling, were open for a wall washing, and balanced that and gave us a range of tools of range of accessories. And my experience is whether the lamps look like this or an array of lamps, my experience is that they retrofitted very well. And they work very well with my lenses. Results may vary, you need to test on your own. There’s not a lot of competitors to Satco. I hear Phillips is making a remote phosphor source but I am honestly not seeing it in museum markets. They’re building a track fixture that’s pure LED, manages heat beautifully, and uses this module which we’ve got a lot of confidence will be more color stable. Just this week, I think it was Sunday night, Satco released a warranty which is another reason I don’t mind mentioning, for color stability. So, they’re willing to warranty that this product to only diminish color very, very slightly. The LED manufacturers for this type of technology, actually calculate about the same color change. But, they’re not willing to warranty it. So, I’m not going to mention their names. Demand warranty. As we manage these complexities and as we manage these warranties. We’re going from a light bulb that costs 5 dollars to a light bulb that costs 50 dollars. So all of a sudden we just can’t throw them away if they happen to burn out. Well, we can but you’re losing all of your payback and all of your investment. So, I think there’s going to be more paperwork, more litigation, and more arguing with the manufacturers. And my experience is a lot of manufacturers have been very good with the warranty but we really have to stick with it, read the fine print before you buy these products and then do your documentation. So, you make sure that they pony up if there’s a problem. It’s worth taking a moment to talk about how all this lighting stuff works. i started giving this talk when I was just working with incandescent. And this difference between low voltage and line voltage. It’s the same thing with LEDs. We start with a parabola, Can you see that? Let’s slow down a little bit. Whether it’s an LED or filament at the conjugal focal point, no matter where it bounces off the reflector it goes straight. We’re projecting the illuminant forwards. If the illuminant is tightly focused, it’s going to be a very tight spot. It’s actually more specific that it’s the ratio. Can you see that? Let’s slow down a little bit. Whether it’s an LED or filament at the conjugal focal point, no matter where it bounces off the reflector it goes straight. We’re projecting the illuminant forwards. If the illuminant is tightly focused, it’s going to be a very tight spot. It’s actually more specific that it’s the ratio. -long pause- Oh look at that. Thank you Naomi. It’s actually the ratio between the filament size and the reflector size. Let’s see some examples. This is one of my most common lamps. Five-and-a-half volt, PAR 36 pin spot. The color is extremely yellow. I think it’s below 2700 Kelvin and it’s what I’ve used in museums because it gives me my most narrow distribution. The light’s right there and it stops. This is about the same size reflector but with the larger filament. We’re looking at incandescents and you can see, same size spot but throws light all over the room. This is a Satco module. Satco used to just make 22 millimeter discs. The fixture designer would say you need to take a garbage cans size reflector to make this into a tight spot. You can see it’s got a spot but also throws light all over the room. Since then Satco started making a smaller module which will give us much better distributions. Now for the first time I can start saying that choosing between an inexpensive retrofit, and a much more expensive purpose-built fixture, whether it’s chips or remote phosphor, it becomes much more of an equal playing field with that remote phosphor thanks to this technology. This is an example of a 4-degree lamp. And now I’m going to compare that 4-degree lamp on my five dollar bills to give you scale. This is my old incandescent technology and this is one LED I found, the only LED I found, that gives me that four degree optic. And here it is. Unfortunately, this lamp has proven not to be very reliable after a thousand, two thousand hours, it’s going very yellow. Right now, I’m choosing to use it and I keep an eye on it and it goes yellow, I replace it. But of all the LED lamps this is the least reliable that I found. And what i’ve done here is i’ve just screwed into an existing AR111 can. And this is one of our challenges within the museum community is, I’ve been talking about medium screw base retrofits. This fixture compromises two-thirds of my fixtures and there are limited lamp options available for this fixture. I would direct you again to Department of Energy and they do caliper tests of different classes of lighting products. And they’ve evaluated the PAR 36, well actually AR111 series of LED lamps and again they came to the conclusion that, well, six months ago or a year there were very limited options. All of this is changing, everything is getting better and the options greater. But, Thanks to the Department of Energy we’ve got a better idea of how to keep track of what’s going on. These are the various beam spreads I’ve got good examples in both types of technology right now. And no really good quality LED solutions at four degrees. But I’m lobbying hard. If anybody has any ideas, my email address will be on the last slide, please contact me. Why is this so important? All of this distribution stuff? The next series of slides are going to talk about that. Great Sculpture by Paul Manship, Europa. I’ve got a Europa shape light on Europa. I’m going to turn it off, slide off to the left. And you can see how I’m pin spotting artwork. If I were to use the larger lamp, I get a big scallop on the wall behind it. This is the only way i know to make the artwork the brightest thing in the room, by matching the size of the light to the size of the art, or the size of the target, if it’s different types of material. It keeps my shadows small, my spill small and I think provides a really elegant installation. In the wayback machine we, go back to the 1990s, when we had one row of track. And most importantly, wht I want to show you is lenses on the front of the fixtures. When we renovated our museum the biggest thing we did was we pushed those lenses back and we reduced glare. This makes the fixtures more energy inefficient but it makes all the difference in the galleries. So I’m always balancing, I’m in a museum. I’m not in an office building. I’m not just looking at energy efficiency, I’m balancing the aesthetics and how we can do the best for our energy bill, our paybacks, and the environment. This is a neat thing I wanted to show you again. This is a second floor before installation you see the lenses on the front of the units. Different wall color. Different fixture.Very much cleaned up. This is a wall wash fixture which is open to the wall but closed and shielded to the viewer. This is what it looks like up close. This is the same idea in a different type of fixture. This fixture isn’t going to spread the light quite as high on the wall, both fixtures come with array of lenses. These are all asymmetric lenses. That is really important because when you just take a round distribution light and aim it at a wall, you’re going to get scallops. Let me show you what I mean. I don’t want to forget to tell you, within your maps you’ll see this is one of the galleries. This is all LED. This is the lamp, I pulled lamps out for testing. When you go up to the galleries, today, I left those left it raw, just like it is. So you can see the difference in some these color changes. That’s important because when you look at things in a lab and you look at thing just on a white wall, comparing things, sometimes they look worse than, when you go out in the real world and you see what those differences look like. This is an interesting slide, in that this is incandescent and this is led. Let’s take a better look at this wall and I’m going to show you how I light art. I’ve got two layers of light, a wall wash and spotlighting on the walls. Lighting the painting, very very specifically. I’m going to turn the spot lighting off, you just the wall wash. This is sometimes the only layer of light that you’ll see in museums. It’s a fine way to work. If I take those asymmetric lenses out, you get scallops. You see this in galleries all over the world to my mind this is not an okay way to work. I don’t think it says anything about the artwork’s composition and it says nothing about the architecture. So, I add the lenses back in. This I think is much more appropriate for at least this installation. And then I spotlight the artwork. The artwork itself is lower reflectivity so it allows me to light the artwork brighter without blowing out your eyes, by lighting that white wall super-bright. I do it very carefully with great attention to the composition of those paintings. And that takes us to color, and within my education of leds I learned more about color than any other attributes or controllable qualities. When I think about color and when I think about controlling color, I think of it in these three criteria, What is the chromaticity? I have to ask you again how many people have heard the word chromaticity? So a little bit more than the other. This is what is apparent about the color of light. You take it and aim it at a white wall, what color is it? I’m any color, the color white, the color blue, color green. Color rendering you need something with a broad range of colors in order to see. And damage factor is that last component which is how to spectrum effect damage potential. I found it enormously beneficial to have a spectrometer. There’s lots of different way to measure color, but with the spectrometer, you get all of the energies so you can calculate the damage function, you can calculate all of the various color rendering indexes and I’m very much balancing between looking at the metrics, doing mock ups in my lab and then testing in the museum and I think you need to do all three points. On the metric side it’s very important. I do not choose a lamp because it has a certain metric and I do not exclude a lamp because it has a certain metric. Because while the metrics are extremely useful they are limited in their ability to describe the full complexity of the human experience. So, welcome to my shop it’s a bit of a mess and this is where i sit for hours looking at colors. This is unprocessed looking at light. I’m assessing light just like color rendering index. This will work in the same way. I started talking to a vision scientists saying i’m doing a subjective test. And she said no. If you’ve got two of the same color samples, this is an x-ray color checker, you’ve got two of the same Kelvin temperature, you have the same illuminance, Kelvin temperature is chromaticity, I’ll tell you that in a second. Then you’re actually doing an objective test unprocessed by the real world and all those things we think about when we’re looking at art. So, this is color rendering. The splash of light around the colorchecker is chromaticity which is measured in two ways. Most of us are familiar with Kelvin temperature which measures how yellow to blue a lighting source is. This is my last question for you. and I’m and I’m interested because I’m an evangelist for these metrics. DUV. How many of you have heard of DUV? Oh this is great, I’m so glad I’m not mentioning it. So, Kelvin temperature is yellow to blue. DUV tells us whether it’s pink or green. Humans, that’s us, we are more sensitive to the pink to green switch, than we are to the yellow to blue. Yet, we only talk about Kelvin temperature and I have no idea why. So. in short if it’s a minus DUV, it’s pink. If it’s a plus DUV, it’s green. This isn’t good and bad. There’s strong evidence that humans prefer, especially at more common color temperatures, things to be a little bit pink. Daylight is on the green side. When I talk about chromaticity people have very strong feelings about it. I think it’s a design choice and we white balance, again as a species. So, if you give us any single chromaticity we will see white. If we’re in there long enough, if it we’re in that environment long enough, the only thing I do know, that is coming from the scientific literature, that Kelvin temperatures 3500 and above, you see more blue. I told that to my curators and director, the didn’t care. They weren’t interested in necessarily seeing more blue of their work. They didn’t want to increase the color gamut. They wanted more harmony between the colors. They wanted actually squash the color gamut. That’s fine. And actually, I’ve spent hours looking at what that means in the lab and it’s fine with me as a designer. I think it’s all a matter of preference and choice. It used to be a real problem having LEDs be different colors, lamp to lamp. Especially in our art museum where we’re doing wall washing. This is especially a great concern. I’ve had very little problems out of the box with lamps being different colors. There’s a few outliers, but for the most part they’ve been very good. And most importantly while I’ve had color stability problems, for the most part they’re all changing at the same rate. At least any one chipset of lamp is changing at the same rate. That’s what it looks like if you put it in the painting. Still matching the size of the light, now with an array of light, to the size of the artwork. Color rendering index, gets into complexity, understaing how this metric works is extremely valuable. And Joe Padfield will be getting deeper into that. I only wanted to say a few things about it. Color rendering index has a reference and a test. CRI just as a fidelity metric that measures the Delta between the two, what’s the difference? It does not capture through the components of saturation. Any difference in saturation is devalued in CRI. This is Delta chroma for a different color sample set of CQS. This I find to be an extremely valuable metric on its And it’s one you have to dig deep into that CQS spreadsheet to find. I don’t know where else to find it. I almost call this a cartoon index. On the extreme side, we can make things look a lot more colorful. On the other side, we can make things look more like, I don’t know, the USSR, East Germany, gray and pale. Roy Burns has actually done incredible work talking about this vision science and how we can start to manipulate spectrum. Color rendering index does not capture these aspects. The other thing that Roy Burns talks about is metameric pairs. I’ve never seen an assessment method for taking a lighting source and seeing how it’s going to render metameric pairs differently. I’m very interested in working on that research. Within making things with more colorful, I do wish I had more LED options available that increase saturation. That becomes a really tricky thing for museum and controversial. There’s artists that would love it, this is actually an installation by Olek. This is a 16 x 16 room, that’s a person all crocheted. If I could get a higher saturation color lamp in this exhibit she would love it. I’m running out of time so I’m gonna start popping through these. My big wish list is lamps that maintain color over time. I’m doing research on this constantly learning. The technology is getting better I’m hoping that the color changes that I’m seeing are because I’ve got LEDs that are two years old. They were made two years ago. It takes a while for them to get put into a lamp. I put them in my museum a year ago. They start changing color. Now, this same series LED is much better. So, the color changes that I was seeing, hopefully the next generation will be better. We just have to keep our eye on the ball, keep your eye on your payback periods. My gut feeling is that these lamps will pay for themselves, increase reliability, decrease HVAC costs. Take all of that into account, sharpen your pencils and do the math and I think LEDs will pay off for you. I think LEDs as a community are doing themselves a disservice by saying they’re gonna last 50,000 hours. I don’t expect that out of my LEDs. I don’t calculate my payback periods for 50,000 hours. If you think they’re gonna last 10 years, it’s disappointing to know that the marketing people are exaggerating a little bit. Or the LEDs will last 10 years but they’re not going to maintain their quality. The reason incandescent lights burn out is because they are designed to burn out before they look terrible. LEDs haven’t matured to make those very difficult choices yet. And if you look at my presentation you’ll see I’ve got tons of data showing this phenomena and how my lamps are changing color. It’s not just my museum, Hirshhorn is kind enough to let me go and take my spectrometer and measure. They’re seeing color changes there. They are also having quite a bit of trouble with lamps flashing on burnout. So is the Freer and Sackler. What’s interesting is actually these two museums have had more troubles with LEDs than I, but they’re still game to continue retrofitting lamps. They want to do more despite the complexities. National Museum of Natural History I have not heard any complaints because color is less of an issue. Because there’s so much going on in this museum. The flashing light is an issues for them as well. These are LED installations, come to the demonstration room we’ve got lots to show you. There are incandescent examples and LED examples. Some of them are just seeing how does incandescent light can change depending on the intensity. My intern Molly will be in the room to help you this is on the second floor. It’s interesting to note that this is hybrid. The wall wash is LED. The actual spot lighting of the artwork is incandescent. And I did this because the lamps that I used to use for the washing were discontinued. Instead of going to interim HIR, I went straight to LED. My third floor galleries, my contemporary galleries are all LED. And, Thank you, very much. -Applause- -Music playing-

Leave a Reply

Your email address will not be published. Required fields are marked *