
Environmentally Conscious Lighting
Special | 35m 37sVideo has Closed Captions
Scott Lind and Samantha Saeger explain how to fight light pollution with smarter lighting.
Scott Lind, electrical engineer and president of the Kickapoo Valley Dark Sky Initiative, and Samantha Saeger, president of DarkSky Wisconsin, explain how light pollution harms wildlife, ecosystems and human health, and share practical, affordable solutions to help protect dark skies without sacrificing safety and efficiency.
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Environmentally Conscious Lighting
Special | 35m 37sVideo has Closed Captions
Scott Lind, electrical engineer and president of the Kickapoo Valley Dark Sky Initiative, and Samantha Saeger, president of DarkSky Wisconsin, explain how light pollution harms wildlife, ecosystems and human health, and share practical, affordable solutions to help protect dark skies without sacrificing safety and efficiency.
Problems playing video? | Closed Captioning Feedback
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Learn Moreabout PBS online sponsorship[gentle music] - Sam Saeger: Hello, thank you everyone for coming today.
I'm Sam Saeger and I'm the president of DarkSky Wisconsin.
My connection to the Dark Sky began when I visited Newport State Park in Door County.
It's Wisconsin's only Dark Sky designated park, and it was there where I truly understood the power of the night sky, when I was standing under the star-filled sky... and while I was taking in the Northern Lights.
So, I'm fortunate today to be joined by a co-presenter who brings additional expertise and perspective, and I'll turn it over to him so he can introduce himself.
- Scott Lind: Hello, I'm Scott Lind.
I'm the president of the Kickapoo Valley Dark Sky Initiative in Vernon County.
Also an electrical engineer with Mead & Hunt in Madison.
And I have an electrician's license as well.
So, I do a lot of hands-on work with Dark Sky lighting.
And so, that's what I'm here for today is the part that I'll share with you is the how-to part after Sam speaks first.
- Samantha: So, why are we here today?
What I realized that night in Newport State Park is that many of us have slowly lost the experience of what true darkness is, and not because we intended to, but because of how we light our communities.
So, this has caused an increase in light pollution so much that it's increasing 10% every year and doubling every eight years.
We've seen even faster jumps of light pollution in Wisconsin.
The impacts of light pollution are well-documented and measurable.
But the good news is, is that it's solvable and reversible.
And the solutions are straightforward and they're practical, inexpensive.
And so, this means change can happen locally through our homes, area businesses, and in our communities.
So, we're here to create awareness and not to place any blame, but to show that reversing light pollution is practical and not extreme.
So, what is light pollution?
It's not just a lot of light.
Many people assume it's only a big city issue, something that only affects skylines or major metro areas, but it's actually a growing environmental issue worldwide.
And at its core, light pollution is simply light used where it isn't needed and when it isn't needed.
And most of the time, people contribute to it unintentionally.
And so, in fact, you've probably seen examples in your neighborhoods of light pollution.
So, there's four main types of light pollution.
And the first is skyglow, which is that bright dome that you see over communities at night.
It doesn't affect just big cities.
It's even small towns have skyglow.
There's also glare.
So, glare doesn't just create, like, visual discomfort.
It actually reduces our visibility.
When light is too bright or poorly shielded, it decreases that contrast and makes it harder to see clearly.
The third is light trespass, and this is one of the most common neighbor complaints.
And it's simply light shining where it doesn't belong, like into a bedroom window.
And finally, there's clutter.
And clutter is just too much bright light grouped together.
And it creates this visual chaos, distraction, and can actually reduce safety instead of improving it.
This image emphasizes misdirection of light and the overuse of lighting creating glare, light trespass, and the visual discomfort.
You can see the man saying, "Oh, my eyes!"
[audience laughs] Before we go any further, though, I want to reframe something.
That the night is natural.
It's not bad, it's not inherently unsafe.
It's essential for life on earth.
And darkness isn't an absence of something.
It's our natural condition.
So, life on this planet has evolved under predictable light-dark cycles.
And for billions of years, there was day and there was night.
So, when we use artificial light at night, especially in ways that are excessive or misdirected, like you just saw on that slide before, we begin to disrupt that natural rhythm.
And that disruption doesn't just affect the stars.
It affects wildlife, ecosystems, and it affects us.
And so, understanding that darkness is biological.
We've evolved under dark skies.
Our sleep cycle, our hormones, even our mental health are tied to all natural patterns of light and dark.
So, when we talk about environmentally conscious lighting, we're not talking about eliminating light.
We're talking about preserving the natural night and using light in a way that respects it.
More than half of the world's species are nocturnal.
And I really appreciate this quote from Travis Longcore.
He says, "We too quickly forget we don't perceive the world "in the same way as other species, and consequently, we ignore the impacts that we shouldn't."
What this reminds us is that we tend to design the world based on how we experience it, and we forget that other species experience light very differently.
And so, wildlife doesn't get a vote how we light our communities.
Modern lighting has largely been designed for human convenience, and humans are the only species that assume night should look like day.
And when we change the night, we're not just changing the sky.
We're affecting a huge portion of life on the planet.
Many of the impacts are invisible to us, but they ripple through entire ecosystems.
Artificial light at night is also called Alan, A-L-A-N.
It disrupts feeding, migration, and reproduction.
It interferes with that natural circadian rhythm, not just for animals, but for plants as well.
Insects are also extremely vulnerable.
Both nocturnal and diurnal insects are negatively affected by artificial light.
And you've probably seen this yourself.
When insects are trapped and they're circling endlessly around a bright fixture.
That behavior isn't harmless.
It exhausts them.
It makes them easy prey, then, and disrupts their pollination patterns.
And birds.
Birds are another major example, particularly during the peak migration periods in spring and fall of being affected by light pollution.
They navigate using the stars and the moon.
And so, when these bright city lights come in, it draws them off course.
It can lead to disorientation and fatal collisions with buildings.
It doesn't stop there.
There's the sea turtles and frogs and pollinators.
Many species experience light very differently than we do, and even those subtle changes in nighttime brightness can alter their behavior in ways that we never see, but still matter deeply.
And light pollution isn't just about losing the stars, which are great in the sky, but it has environmental consequences.
In the United States alone, wasted outdoor lighting costs an estimated $7 billion in energy every year, and that wasted light results in the release of about 66 million tons of carbon dioxide annually.
So, those emissions aren't coming from lighting that we're using to improve safety or visibility.
That's coming from light that is misdirected, excessive, and simply unnecessary.
So, in other words, the carbon emissions are a direct result of that wasted light.
Just as light pollution affects wildlife, it also affects, and the environment, it affects us as humans.
Our bodies depend on that natural light-dark cycle.
Our circadian rhythms, the internal clocks that regulate our sleep and our hormones and our overall health, really rely on that darkness at night.
That blue rich light that you are getting from your electronics and certain outdoor lighting is particularly disruptive after sunset.
So, it can interfere with melatonin production, impact your sleep quality, and increase stress over time.
And this is important to note because we are not separate from nature.
The same biological system that guides wildlife also guides us.
And so, this conversation isn't about fear.
It's about awareness.
And when we choose smarter lighting, we're offering practical solutions that will protect the health of people, wildlife, and our environment.
Losing the night sky isn't just environmental.
It's also cultural, emotional, and scientific loss.
Today, about one third of humanity, so that's roughly 80% of people in the United States, can no longer see the Milky Way from where they live.
And for most of human history, the night sky was a shared experience.
It shaped navigation.
It was storytelling, it was science.
And it was our understanding of our place in the universe.
And so, darkness inspires curiosity.
It sparks wonder.
It encourages stewardship.
And when we lose the night sky, we're not just losing the stars, but we're losing a source of that perspective, imagination, and connection that has guided humanity for thousands of years.
One important thing to remember is that light doesn't just stay contained to one property.
It crosses property lines, and a single poorly aimed light can impact your neighbors, as we talked about before, wildlife, and even the sky itself.
So, this isn't about individual perfection.
This is about collective awareness.
When communities work together and adopt thoughtful lighting practices, the impact is far greater than any one person acting alone.
And the good news is, is that communities can protect darkness while still maintaining visibility and safety.
Smart lighting allows us to do both.
When we talk about lighting, good lighting design, sometimes the best design is choosing not to light something at all.
And for example, choosing not to uplight a tree or architectural feature on your property, that can feel counterintuitive to people.
We've been used to thinking that adding light adds value, enhances beauty, or improves the space.
And for many people, the idea that not lighting something is a valid design choice, that can be the hardest choice to accept.
But in many cases, restraint is the most environmentally responsible option because it recognizes that darkness isn't something to eliminate.
It has intrinsic value.
So, what does it mean to actually not light beyond what's needed for safety?
It means being intentional.
It means lighting for a purpose, not simply lighting because we can.
In many communities, the most respected and beautiful properties aren't the brightest ones, but they're the most thoughtfully designed.
And so, choosing not to use excess light is-- It doesn't mean neglect.
It means that you've considered what's necessary, and lighting, understanding that lighting doesn't always communicate values.
In the past, more light was often associated with status or success.
But today, we understand that excess light doesn't equal quality.
Thoughtful lighting, light that is purposeful and limited to what's needed reflects a community that values both safety and stewardship.
There's a common belief that more lighting automatically means more safety, but we know that isn't necessarily true anymore.
Brightness alone doesn't equal safety, and safety isn't about flooding an area with light.
It's about using well-designed lighting that improves the visibility without creating visual discomfort and that glare that I mentioned before.
But with the well-designed lighting, we can improve safety.
So, where did this come from?
This brighter meaning safer?
And the idea isn't a bad assumption, that brighter is safer.
It's just an old one.
It's outdated.
When lighting and security technologies were more limited, they had to increase the brightness.
And it was the simplest solution and the most effective solution when those technologies were limited.
And historically it made sense, but our perceptions of safety have changed and no longer are shaped by those technological limitations.
So, today that leaves us with brighter does not mean safer.
It does not mean better vision.
In fact, excessive brightness is creating that glare that we've talked about.
It reduces that contrast and it limits our ability to see clearly.
Harsh lighting creates shadows, and overlighting can have the opposite effect and actually make areas feel unsafe because of the glares provided by that overlighting.
And this is a goodvexample of glare reducing safety and hiding those details.
So, there is a person standing at the gate in both of the photos.
You just can't see him in the first photo because of the glare.
So, you can see in the second photo by shielding the fixture with the hand, the lack of that intense glare means you can see him in the bottom photo.
So, today, technology has changed.
We have better fixture designs.
We have full shielding, adaptive controls, motion sensors, and dramatically improved camera systems.
And the tools are different now.
So, modern cameras no longer require overlighting to function well.
They-- without changing the equation.
So, security no longer depends on that constant brightness either.
The LEDs allow for precise control of direction, intensity, timing, and color temperature.
So, we've moved from a mindset of "light everything" to "light what matters."
And the rules have evolved, and it's time for our assumptions to evolve with them.
So, the mindset shift that we're asking and inviting you to is not a fear of darkness, but really confidence in smarter lighting.
We can rethink our old habits without sacrificing safety and security.
This is a new way of thinking about safety.
And instead of thinking we need brightness to feel safe, we want safety that comes from consistency and creating visibility where it matters most.
And with lighting that's even, that improves clarity instead of glare.
Confidence comes from this intentional design and the understanding that darkness and safety are compatible.
So, security today doesn't come from floodlights.
It comes from that visibility, that control, and intelligence.
So, when a neighbor believes that more light is better, one of the common questions we hear is, "What do I do if my neighbor's light is shining brightly into my window?"
And the first step is to assume good intent.
Most people, lighting issues aren't intentional.
They're often very easy to fix.
And instead of focusing on judgment, maybe focus on the impact.
And so, you might mention sleep disruption, some of the things you've learned today about glare or the effects on wildlife.
And rather than implying that they are doing something wrong, focusing on what the impacts are.
And so, it can sound as simple as, "I recently learned a little bit about Dark Sky "and lighting choices at the Garden Expo.
"I noticed some light from your fixtures shining into my window.
"I was wondering if you'd be open to adjusting it or using a warmer bulb."
And so, there's ways that we're trying to encourage people to have those conversations with neighbors, educating them.
And also, no pressure, but just making sure that they know that there are other opportunities and solutions.
So, it's not about confrontation.
We just wanna have conversation.
And the good news is that most of the solutions are simple.
And Scott's going to walk you through what those practical solutions are.
- Thanks, Sam.
Okay, so Sam has done a great job of introducing you to the overall problem.
And we'll talk a little bit more now about the details about how you can accomplish environmentally conscious lighting.
What are the practical details to do that and some examples of that.
So, it's lighting that's only used when it's needed.
It's lighting that's shielded.
It's warm in color, which most people aren't widely aware of how important the color temperature of light is.
We're gonna talk about that a fair amount today.
And then appropriate brightness, right?
So, these are the only three definitions we're gonna use.
We're gonna keep this as nontechnical as possible.
But we do need to understand some basic ideas.
So, I'm gonna talk about zero uplight fixtures, and the fixture on my right, your left up here is a zero uplight fixture.
There's no lens visible from the front.
I'll turn these on later for you.
The fixture on your right, my left is a very common fixture we see everywhere, which has a lens on the front, and we'll throw light directly into your eyes, unlike the fixture on the other side.
That's a very important characteristic to prevent direct uplight into the sky and to reduce glare.
The lumens, we all know about a 60-watt light bulb.
If I say 60-watt light bulb, for most people in this room, that means something to you visually what that means.
But if I said 900 lumens, does that register at all?
It probably doesn't, right?
Unfortunately, because the efficiency of light fixtures has changed over time, from incandescents to compact fluorescents to LEDs-- LEDs have continued to become more efficient-- if we think about lighting in terms of watts, we have no idea what that really means.
Even though we think we might know what that means, we really have no idea what that means.
And so, it's really imperative to start to think about what a lumen is.
What is 900 lumens?
And the best way I would encourage you to do this is to go to the hardware store and buy two or three light bulbs with different lumen outputs, and put them in a lamp in your house with the rest of the lights off in the house and turn them on, and just get a-- start to get a sense of what those numbers feel like.
It's really important to get to that point in understanding outdoor lighting, especially.
And the last definition is correlated color temperature, CCT, that's what the second C stands for.
But it's the color temperature of the light.
Has nothing to do with the brightness.
No relationship whatsoever about how much light you're getting.
It's strictly about what the color of that light is.
Okay?
So, I've got a picture of that fixture turned on in this slide.
And there's a couple of examples here of other types of zero uplight fixtures.
But there are many different shapes and many different forms available.
It's just an example that tries to show you that the lenses are always on the bottom.
If you look straight at that fixture and see any lens, it's not a zero uplight fixture by definition.
And this is how I try to represent lumens.
In other words, this is strictly quantity of light.
Ignore the glary street lights.
Ignore the fact that they're very, very white, right?
We'll talk about the fact they're too white a little bit later, but just look at the quantity of light in those two images, right?
That's all I'm trying to demonstrate for you.
And then, color temperature.
So, as we move through daytime into dusk, the middle of the day is roughly 5,000 to 6,500 Kelvins.
That's the measurement for correlated color temperature.
It's measured in Kelvins.
And then, as we get more and more towards night that Kelvin number decreases.
And so, if you go into a store and look at a light fixture box or a light bulb box, you'll see a four-digit number followed by the letter K. That is the color temperature of that light bulb or that fixture.
And the lower the number, as counterintuitive as this is, the lower the number, we describe that as warmer.
That's a warmer light, a warmer-colored light.
And that's the same transition that happens with natural light.
It starts out during the middle of the day, very, very blue, very high Kelvin number, and then goes down as we get closer and closer to night.
So, here are some images of different color temperatures.
And this fixture here will also demonstrate for you later, the ones that are in the room here, 1,800 Kelvin is about the lowest we can find today as a color temperature of light.
It's very gold, very, very warm.
2,200 Kelvin is the first light that the standards define as white light.
So, it's a very warm white light.
And 2,700K is also a warm white light, a lot like incandescent lamps.
If you think about incandescents, they're very close to 2,700 Kelvin.
Here's an example of an installation in La Farge, Wisconsin.
This fire station has 1,800 Kelvin lights on it.
In fact, the same light that's up here in front of you.
And the folks in town are extremely happy with that lighting.
And it's very, very warm and has very low glare and very low skyglow potential because it's such a warm light and because it's directed downward where it's needed on the ground.
So, why are we focusing so much on color temperature?
So, a higher color temperature scatters more.
There's more blue in those higher color temperatures and that scatters in the atmosphere.
It's called Rayleigh scattering.
The same reason the sky is blue during the day.
You take the full spectrum light of the Sun, blue light, short wavelength light scatters more in the atmosphere, and that's why the sky is blue during the day.
The exact thing hap-- That same thing happens at night when you take an artificial light that has blue light in it.
That blue light scatters more than the other colors do, so it creates increased skyglow because of that fact, even light that's directed down.
As soon as the light leaves that fixture, it begins to scatter in the atmosphere.
Species, humans, other species are sensitive to different wavelengths in different ways.
And so, the spectrum of light is really important, okay?
And then, higher CCT with more blue in it, as Sam explained, affects circadian rhythms and affects sleep patterns and has lots of other impacts to the environment beyond just scattering in the atmosphere.
So, that's why we're gonna focus a little bit on correlated color temperature.
And this graphic will just kind of show you as we go up in color temperature starting at 2,200 Kelvin, 2,700, 3,000, 4,000, 5,000.
That that dramatically raises the skyglow potential from those different color temperatures.
So, when you go out and buying a fixture or buying a bulb, every time you go up in number behind that-- or in front of that K number, you're increasing skyglow pretty dramatically.
Here's one example just comparing two different light sources, 2,200 Kelvin, and what a color chart looks like lit under that light source.
And what a 4,000 Kelvin, which is very, very common now, how that illuminates that color chart.
You can see the color rendering, how those colors appear to us under those different light temperatures.
But the most important number up there to me is the fact that 78% more skyglow from the 4,000 Kelvin image for the identical fixture, the same amount of light.
All you change is the color of the light.
That's it.
And it increases skyglow by that much.
So, the question I have to ask is at night, right, we're not picking out the clothing we're gonna buy, is it important to you to have slightly different color rendering if you know when you do that, you're gonna have 78% more skyglow?
That's the question about being intentional and being thoughtful about how we light at night.
That's one factor is the color.
So, the principles of being responsible with lighting at night really are to use zero uplight fixtures, first of all.
2,700 Kelvin is as high as I'd ever recommend you go, and warmer fixtures and warmer bulbs are becoming more available every month, right?
We started with 4,000 Kelvin when LEDs first came out, because that's all that they could produce.
They couldn't really add phosphorus to them at the time.
And as the years have progressed and technology has progressed, as Sam mentioned, we now have more responsible choices available to us.
So, certainly I would recommend nothing higher than 2,700K and ideally 2,200K or 1,800K, 'cause there are dramatic jumps every time you go up in temperature.
So, the lowest you can go, the better off you are.
The other key thing that Sam talked about, turning lights off, and that's also a big part.
Obviously, if the light is off, no matter what color it is, it's not gonna produce any skyglow.
It's not gonna produce any glare.
It's not gonna use any energy.
So, for commercial buildings in the state of Wisconsin, in most states, there are rules about turning things off.
And that's great.
And you should consider doing the same things on your own residential property, even though they aren't mandated unless they're mandated in the community you live in.
So, you can do that by motion sensing, which is ideal from the standpoint that any time of night, even in dusk, right, it won't be on unless somebody is there.
So, that's the ideal, but at a minimum, put it on a timer so that, you know, in the middle of the night when nobody's gonna be out there getting to the garage, for example, that light is turned off.
And then consider putting dimmers on.
So, regardless of whether it's on or off, most fixtures that I see are too bright.
Manufacturers will sell them as being brighter and better, right?
Not recognizing at all when they sell it what the application is.
Where is it gonna be installed?
Do you really need it?
So, by putting a dimmer on a fixture, you can choose how bright that fixture is.
And so, any time it's on, it's on in an appropriate light level.
Or you could choose to combine a dimmer control-- Not one of these, but a dimmer control with a timer so that some times of the night, it's brighter, and then it goes dim, or it's motion triggered so that it goes very, very dim unless it's motion triggered and then it comes up in brightness.
There's lots of options we have today with LEDs that we didn't have in the past.
And so, I'd encourage you to take advantage of those options and do a better job of controlling the lighting that gets installed.
So, simple actions you can take at home.
Obviously, again, using zero uplight fixtures, using the lower Kelvin temperature lights, using motion sensors or timers we just mentioned.
Really asking you to think about the intention of outdoor lighting that Sam mentioned earlier.
If you're talking about decorative lights only, lights that aren't trying to get you down the sidewalk, but just decorative lighting on your property or landscape lighting, think about whether that really needs to be on more than just very short time periods.
You have guests coming over, for example, or whatever it might be, think about limiting how much of that you have.
And then another contributor, Sam mentioned birds being in, having impacts with windows.
Another big contributor to outdoor light at night is actually interior light spill through windows.
So, if it's possible and you have blinds, consider putting your blinds down to reduce the amount of artificial light going outside.
So, that's individually.
What communities can do, I really encourage this.
We've done this in Vernon County, in the communities of Ontario and Wilton and La Farge and Cashton and Westby.
We've done places where we had public lighting, and we've changed that public lighting and used those as examples for other people to follow.
And so, the illustration that I'm gonna show you next is from the Ontario Fire Station.
That was the first project I did.
And having that example available in the community led to many other projects being done, because I can stand here and talk to you about this.
I can even show you a fixture in a lit room during the day, but if you walk by a building at night, that's been done in a way that's responsible and you like it, that's much more likely to have you say, "I don't mind that.
"That looks good.
In fact, I like it better."
And that's what I would encourage you to consider doing if you wanna have an impact on better lighting in your community is to pick one example, just pick one building, whatever it might be, and change that building and use that to educate your neighbors.
So, this is a before picture of this fire station.
It had a combination of unshielded, you know, I call them glare bombs with the lens on the front, like the one you see on your right up here.
High pressure sodium, which is the legacy technology for outdoor lighting.
And then, 5,000K LEDs, which is the middle fixture in this is 5,000K LEDs.
And this is the after picture.
This is 1,800K LEDs.
Again, using that same fixture that's in the room right here.
The light levels are still brighter than the standards would call for, okay, but they're identical.
I used dimmers to control them precisely.
So, I kept the light levels on the paved areas identical to what they were before, average and minimum.
And the uniformity, the light, how uniform the light is, which Sam mentioned how important uniformity is.
That's a kind of a gold standard for lighting designers is how uniform you can make that light to get rid of the bright and dark spots.
That improved by 35% just by changing the fixture from a glare bomb fixture to a controlled downlight fixture.
Energy use was reduced by 75%.
Skyglow was reduced by 90%.
Here's another example at Wildcat Mountain State Park at the entrance station, for any of you that have been there.
I call these interim changes because we're gonna do more changes to this building and make these fixtures even warmer.
But this was an interim step.
We changed all the LEDs, which were previously 5,000 Kelvin, as blue as you can get, practically, 5,000 Kelvin, to 2,700 Kelvin.
And we had dramatically less skyglow just from doing that.
But also, if you look on the picture on the left, you might notice there's a floodlight up lighting the flag.
In the revised version, we put a top mounted flagpole light on there.
So, we took what was, I think, 150-watt metal halide fixture shining up at the flag and replaced it with a, I think it's a 10-watt LED shining down on the flag.
So, that had a huge impact as well.
And many people have commented when we look at these images that the new image looks brighter than the old image.
And that's because the camera, when you take these images, reacts the same way your eyes do.
And so, that bright floodlight, right, that was shining at the camera lens, not directly, but indirectly at the camera lens, gives a different perspective on what the actual lighting levels are.
So, what are the benefits beyond just darkness?
There's obvious energy savings.
The Ontario Fire Station example that I gave, I installed those fixtures, I didn't charge to install them, had a two-year payback because of the energy savings.
Obviously lower utility costs embodied in that.
Reduced carbon emissions that Sam mentioned.
You know, we aren't storing much energy yet at night.
And as of today, most of the energy we're using at night is still carbon-based energy, you know, gas turbines or coal-fired plants for the most part.
So, all that light that we're using at night that's wasted is, for the most part, contributing to our carbon problem.
Better nighttime visibility, I talked about the improved uniformity, and when I turn these fixtures on here, I think you'll all experience, even in a room that's lit this brightly, but certainly from your memories at night when you drive, especially in the countryside, but anywhere, if you drive, especially in the countryside, these incredibly bright lights shining into your eyes, how that reduces your visibility, makes you think maybe that's a car coming down the highway, but no, it's just a barn with a light on it, right?
That kind of thing.
And then, as Sam mentioned, healthier ecosystems.
All the things that we're talking about will improve the health of the ecosystems in general.
So, how do you get involved?
Start by making small changes at your home, talking with your neighbors and community leaders.
We'd encourage you to initiate local Dark Sky efforts.
That has the highest chance of success.
If you can get involved in your local community, that's gonna be great.
And then share what you've learned today with other folks so they can benefit from this knowledge.
You know, darkness is not lost forever.
It really is not.
We have an opportunity by making good choices, simple choices, actually, we can restore the night for ourselves and for all the other species.
And that's why we're here today.
And we would encourage you to join us in doing that.
So, I think we have time before we do Q&A.
I will turn the light fixtures on if that's okay.
Those of you sitting directly in front of this one... If you'll be sitting directly in front of this one, might want to close your eyes just briefly, but.
So... Oh!
[Scott chuckles] [attendee exclaims] Yes, exactly, sorry about that.
I'll turn it back off again.
So, I'll just say that I've done calculations for buildings with those types of fixtures and with these types of fixtures on them, and I can achieve almost identical distance from the building light levels.
In fact, when I turned these on earlier, the question was, "Well, what about that one being on?"
It was on, right?
But because you don't see that direct glare, you don't realize how much light it's actually putting out.
That's the beauty of LEDs now is that with the LEDs mounted at the bottom of that fixture, each of those discrete LEDs has a lens on it that focuses light.
And so, that light, even though it has a lens in the bottom, is capable of throwing light out at very high angles, for better and worse.
But in the case of this, it's better from the sense of being able to throw light further out without giving you the direct glare.
So, that was the purpose of showing those two fixtures.
I can talk more about color temperature and so forth, but we've already covered that earlier.
All right.
Well, we thank you all for coming.
Sam and I are grateful for this opportunity.
[audience applauds]
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