Happy Winter Solstice

December 23, 2011 / no comments

Lam Partners

Yesterday was the winter solstice. It is a time that we often associate with Christmas, Yuletide, Hanukkah, or the Feast of Saint Lucia. Candles are lit, trees and rooftops are decorated with strings of light, parties are held, and gifts are exchanged. The lighting of lights to relieve the cold and dark of this time of year symbolizes hope and perseverance. It might be surprising, then, to learn some of the other ways that the longest night is celebrated throughout the world.

Lam Partners

The word “solstice” is derived from Latin words meaning “the standing still of the sun”. While the winter version is most commonly referred to as the shortest day of the year, it is actually a point of inflection which occurs at a specific time: this year it was December 22 at 5:30 UTC. The time refers to the precise moment when the northern hemisphere has reached its furthest distance from the sun before dramatically shifting directions.

Historically, celebrations surrounding the solstice are as much about this critical turning point as they are about darkness and light. Many, such as Goru among the Dogon people of Mali, mark the end of the harvest season and the beginning of winter.

Other traditions, however, reflect the transition by taking on a subversive form, where participants engage in activities that upend the standard order. Bacchanalian festivals in Ancient Rome and Greece such as Brumali or Saturnalia were times of casting off social restraints, of drinking and merriment, and of some other, more unusual, customs: slaves would enjoy a banquet served to them by their masters.

Lam Partners

Lam Partners

This reversal of order is achieved elsewhere by wearing disguises. In the Junkanoo festivals celebrated in the Carribbean, parades feature elaborate, symbolic costumes. The Cornish custom on Mummer’s Day is to march through town with blackened faces or masks. In several traditions, ghost stories are told, and spirits are said to haunt the living, as in the Scandinavian Feast of Saint Lucia, during which the demon Lussi is said to frighten children who have not been good.

Lam Partners

Lam Partners

Other cultures simply embrace the longest night by staying awake for its duration, such as the Persian festival Yalda, or Shab-e Chelleh, in which families gather together to feast on pomegranates and dried fruits, stay up all night, and listen to poetry. Celebrating throughout the night was also the custom of the Inca and of the Mapuche of Chile (though their rituals for the longest night of the year in the southern hemisphere took place on the opposite solstice in June). The observers would stay up several nights waiting for sunrise, celebrating the assurance that the sun would return.

The eventual triumph of light over darkness and the symbolism of renewal are some of the strongest themes prevalent in these celebrations. Sol Invictus from the Roman Empire translates as “the undefeated sun”. The Kurdish _ewy Yelda portrays the sun as being reborn after the solstice. In contrast, Dong Zhi in China celebrates the “arrival of winter” and the interrelationship between darkness and light as part of the yin and yang philosophy. Families gather, and a sweet soup made with pink and white rice dumplings is served.

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While we often think of the winter solstice as simply the shortest period of daylight in the year, throughout history and the world, there is a richer picture. However you are celebrating, have a happy solstice.

Photo Credits: NASA Goddard Space Flight Center (1), Andrea Rota (2), Antoine-François Callet – Musée du Louvre (3), MissChatter (4), Fredrik Magnusson (5), Eliza Tasbihi (6), Oranje (7)

Dispatches from Lightfair

May 31, 2011 / no comments

Every year, many of us here at Lam attend Lightfair® International, an annual lighting trade show and conference, allowing us to keep up to date with products from hundreds of lighting manufacturers, as well as design tools and technologies, standards and practices, and industry-wide trends and innovations.

The following are some of our impressions of this year’s event:

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Lightfair seems to be turning into more of an electronics show than a lighting show. But, I saw a lot of LED products this year that gave me hope about LED lighting in general. My favorite: retrofit LED lamps that are actually a good replacement for incandescent lamps! Sure, these things have been around for years now. They cost a fortune, last about a month, produce hardly any light, and the light they do produce is garish. But what I saw at Lightfair was lamps that dim, have good color, produce useful light, and are affordable! This is very encouraging. There are lots of wonderful products that can produce a low-power-density lighting design for a new project – but the majority of square footage in the world is not new, it’s existing. Affordable retrofit products that are actually starting to look good is a great step forward. We may even be able to reach the Architecture 2030 Challenge!

Other LED products I saw that give me hope are interchangeable light engines. They’re like LED light bulbs. There’s an industry-wide movement, called Zhaga, that is trying to standardize the specifications for the interfaces of these light engines. So instead of throwing the whole luminaire into a landfill, we can now recycle and replace just the LED module.

The trade show itself was also encouraging. I was in New Orleans to attend the AIA convention the week prior, where the floor was dead compared to Lightfair. Is it because architecture is still hurting economically and there were just not as many people attending? Or is it that architects are chasing CEUs and attending more seminars rather than walking the trade show floor? Either way, Lightfair was wonderfully crowded and vibrant this year. People in almost every booth gave me hope that the industry is coming back. I ran into a lot of colleagues who said work was picking up, or that they were very busy. A sense of optimism seemed to be the brightest luminaire at Lightfair this year.

– Keith


I had two basic missions at Lightfair. The first was to check out innovations in current and upcoming lighting design software, and the second was to attend the IES Daylighting Metrics Committee meeting.

Tools to evaluate lighting are in a state of flux. Some lighting and daylighting metrics have progressed in sophistication, but the software has not yet been developed to employ all of them. Revit is becoming not only popular, but required on many projects, however, coordination of lighting into Revit models is still far from commonplace. This was clear in the short session I attended about BIM modeling, which showed many important capabilities of a variety of softwares, while also showing that in practice, transferring information between programs can be tedious and time-consuming (though one particularly bright spot revealed at Lightfair is a plug-in being developed for Revit which allows lighting analysis of Revit models without manually transferring the model into AGi32 and back).

On the other hand, there are good software tools available, but most designers have not yet learned how to use them. Researchers have developed robust and valuable new daylighting metrics that can only be used by a select few with advanced expertise of difficult, esoteric software. This is especially problematic when working with codes like IgCC and LEED. Better metrics can help foster better design, but it’s impractical to require compliance based on software that’s not widely known or easily available. Furthermore, as the Daylighting Metrics Committee discussed, there is a need to standardize metrics so that everyone is working from the same basic assumptions.

The rise of Revit and BIM provides new opportunities as well as challenges. In principle, it should facilitate coordination among architects, engineers, and consultants, but in its nascent stages, there are still a lot of hurdles to clear.

– Kera


After walking the many aisles of lighting booths at Lightfair, I was left with a feeling of brightness. Not with a sense of novelty or originality, but literally, glaring brightness. There was a vast display of LED site lighting pole fixtures looming above, packed with bright LEDs, and causing overpowering glare at almost every corner. As manufacturers touted the universal suitability of LEDs, the fixtures actually on display overwhelmingly revealed some of their biggest disadvantages, with high-angle glare and excessively cool color temperatures.

Even though it was slightly frustrating to walk around the exhibition hall, squinting my eyes to dodge bright LED fixtures, I found the experience to be, in a way, eye-opening, as the ever-present LEDs on display demonstrated the need for much continuing development and innovation before these products become practical.

On the other hand, it was interesting to see some of the manufacturers that are implementing LEDs into thin forms and planar fixtures, taking advantage of LEDs’ unique characteristics and compact quality.

The part of Lightfair I enjoyed the most, the part that left the biggest impression on me, was the keynote speaker luncheons. I enjoyed the camaraderie of sharing design experiences, and learning about the design process from visualization to concept to schematics, mock-ups, and final design. It’s great to simply get to know other designers, and to appreciate the projects from various points of view, with more than just a final photo of the result.

– Amber


My biggest impression at Lightfair was “who are these guys”? There were so many companies that I had never heard of. Seems like everyone sees this big market opportunity in LEDs, and if they can stick a chip into something and make it glow, they are a lighting company!

I was happy to see the development of small-aperture LED recessed fixtures with a choice of beam-spreads, as an alternative to MR halogen fixtures. They are still much more expensive, but the price should come down, and potential payback in energy savings can help. Of course, the lack of standardization in outputs and beam-spreads continues to be frustrating.

Speaking of lack of standards, let’s talk about controls. Unfortunately in this country there is no standard lighting control architecture or protocol. Add to this some really fascinating out-there control systems (low-voltage DC power, power-line carrier, wireless) and it gets really crazy. It will be interesting to see how this will settle out – but in the meantime, we’ve got to design control systems… sigh.

As usual I was disappointed by the lack of new, innovative fixture designs – sure, there were a few things, but none of my colleagues I bumped into were saying “you’ve got to go see this!”. And when it comes to LED (which is pretty much all anyone was showing), this means that I saw very few fixtures that took advantage of the unique form and electrical characteristics of LED. Sure, we need (cost-effective) LED downlights and troffers – but come on guys, use a little imagination!

– Glenn


Meh. Let me put my curmudgeon hat on:

Unfortunately, I feel this way more and more about each successive Lightfair I attend. Perhaps it’s because Lightfair happens too often (try a two-year rotation), but the last three I’ve seen have been dominated by the same theme: everyone trying to convert their standard products to LEDs. The problem is that LEDs are STILL only half-baked as replacements for standard sources and, until the industry agrees on some basic standards (like a replaceable LED module), it’s just the Wild West out there.

What’s more is that everyone is jumping on the bandwagon and copying everyone else. Where there were once two or three LED downlights, now there are 50, all making crazy claims of energy savings and unrealistic lifespans. The copy-catting was so bad this year that I had to walk up and down the aisles ignoring any company I hadn’t heard of before, because the probability is high that you won’t see them at the next Lightfair.

It’s not even a fad, it’s a frenzy. Most don’t even try to innovate – they just use the same old housings and stuff LEDs into them. Those that did their LED homework and are doing some ground-breaking stuff command some respect, and I was impressed to see their recent improvements. Still others, who have built their companies around standard light sources, are proceeding more cautiously, and I can respect them for that as well. But those that simply do it because everyone else is doing it – both specifiers and manufacturers – may end up getting burned in five years when everything needs to be replaced. There will be a glut of crap out there for several years to come. I’m not an LED hater. They have their time and place, but proceed with caution – now more than ever.

Curmudgeon hat off, optimist hat on:

I did see noted improvement in the more design-ey LED stuff. Some manufacturers have embraced the LED’s discreet nature and have developed fixtures around new forms. I saw some three-dimensional forms, curves, planes, stuff sandwiched between panes of glass, and other crazy shapes that really catch your eye (not like those that try to snare you into their booths by impairing your vision with LED headlights). That’s the kind of ingenuity we need to see.

As for controls, I saw a marked improvement in promotion of digital addressable systems, which are definitely game-changing technology. Just like for LEDs, there is currently no regulation or standardization out there, but those manufacturers that really get it are making significant headway. It’s a lot to sort out, but we’re finally seeing progress where for twenty years there had been none. Keep it coming.

– Matt


Image credit: LIGHTFAIR® International (photo by Lam Partners)

Season’s Energy Code Greetings

December 13, 2010 / no comments

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With the onset of the holiday season, we have also come to the end of the three-year energy code development season. The new 2010 version of ASHRAE/IES Standard 90.1 has been published, and IECC-2012 will be published in April 2011. (No, that’s not a typo. IECC-2012 will be published in 2011. Don’t ask, I have no idea.)

It will be a while – years, probably – before IECC-2012 is adopted by states, and at least a year before 90.1-2010 is incorporated into LEED, but the code development community is already looking towards the next versions of these model energy codes: 90.1-2013 and IECC-2015. So, while designers are currently practicing under energy codes that are at least three years old, code geeks have their heads three years in the future. So, what gifts might the next code development season bring us?

Watch the IECC

Historically, the IECC relied on 90.1 for energy code content. With IECC-2012, the IECC lighting section takes on a life of its own. Expect that trend to continue. While 90.1 will likely remain influential, since the IECC is the actual code that states adopt, the IECC may be where the action is in the future.

Stretch Your Codes

Energy codes only set a minimum acceptable performance (the worst possible building that you can legally build?). Institutions, corporations, and governments that understand this are looking for ways to push their energy use even lower. One way to do this is with “stretch codes” such as the Massachusetts Stretch Energy Code which has been adopted by over forty Massachusetts communities. This Stretch Code is an appendix to IECC-2009 that increases stringency.

Another way to go beyond the minimum is through green building codes such as the new International Green Construction Code (IGCC). Green building codes are intended to have energy performance provisions that are more stringent than base energy codes. Because of this, new energy regulation ideas are being proposed in the IGCC development process. Keeping an eye on the development of the IGCC’s energy chapter may give us an idea of what future energy codes will look like.

These advanced code programs, if adopted widely, will make the designer’s job more complex. Not only will they have to keep track of the applicable energy code in each state, but they will have to know if the municipality is using a stretch energy code or has adopted a green building code with its own separate energy provisions. And they may struggle to design to different and potentially conflicting requirements.

Squeeze Out More – a Lot More!

The pressure is on and will almost certainly continue for the energy codes to be more “efficient”. For the last code cycle, the goal was 30% more “efficient” than 90.1-2004. We don’t know what the target off of 90.1-2010/IECC-2012 will be, but I wouldn’t be surprised if we see a proposed target of 30%. Those of us who have been thinking about this don’t see how this will be possible with typical building technology, design solutions, and energy code methodology.

Lighting Power Density is currently the preeminent tool for regulating lighting energy use. The push for more efficiency in codes means pressure to lower LPDs even more. But barring an unforeseen leap in technology, we can probably only squeeze a little bit more out of LPDs if we are to maintain high-quality lighting. We may be able to eke out some more savings by expanding even further the requirements for occupancy sensors and daylight responsive controls. But how do we make big reductions – 30%, 50%, eventually all the way down to net-zero?! Daylighting.

In order to significantly reduce lighting energy use, we’re going to have to really use daylight to extensively light our buildings. If codes require this, a radical change in mindset will need to take place – resulting in major changes in building footprints, orientation, and envelope design.

Guaranteeing the Outcomes?

If energy codes are supposed to reduce building energy use, then shouldn’t we be directly regulating it? The common prescriptive code methods use blunt instruments such as LPDs, minimum equipment efficiencies, and R-values to affect how a building is designed. These methods do indirectly affect the energy use of the building, but the energy use itself (how the building is operated) is not regulated.

In an ideal world, the energy code should just tell us what the end result needs to be, and let us decide how to get there. Expect to hear more about EUI (Energy Use Intensity), measured in kBtu per square foot per year. An effective building energy performance-based code will require more robust, but easier to use, energy modeling software. It will also require a change in the way we design buildings – with a truly integrated design process where the whole design team is working together to get the most out of a limited building energy budget.

EUI may be the way to make the codes much more “efficient” and still allow high-quality buildings to be built – but many details, such as dealing with occupancy/operating hours, will have to be worked out. Look for energy codes to start requiring a building energy performance method for buildings of certain types or sizes.

Even if you perform complete energy modeling, and design to a specific annual building energy use limit, all you are doing is predicting how much energy the building will use on the day it opens, if properly commissioned and operated. Every lighting designer has their horror stories of carefully designed (and expensive!) lighting control systems that were never commissioned and/or operated correctly, leaving all the lights on, even when daylight is streaming in or when no one is around. The building meets energy code, but if it isn’t operated correctly and becomes an energy guzzler, then the code is ineffective. Realizing this, code geeks are starting to look at “outcome-based” codes.

An outcome-based code might require building owners to certify actual annual energy use. How will an outcome-based code be enforced? Will buildings someday need to get an annual energy certificate just like an elevator or health department inspection? And what would the penalties be for non-compliance? Will design professionals be held responsible for the performance of a building that they designed but do not operate?

The Gift That Keeps On Giving

As you can see, energy codes are likely to get tougher, get more complicated, and adopt unfamiliar new methods. Building design professional organizations such as the IALD, AIA, IES, and ASHRAE are all actively involved with energy code development. If you are interested in getting involved with code development and are a member of one of these organizations, you can contribute. Happy holidays!

Photo Credit: Phillie Casablanca

Local Celebration of Light

October 21, 2010 / no comments

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What began in 1984 with a group of people gathering together for a candle-lit journey around Jamaica Pond has become an annual tradition bringing together the local community in the celebration of history, tradition and light.

The Jamaica Pond Lantern Parade takes place on the weekend before Halloween. This year’s event will take place on Saturday, October 23rd and Sunday, October 24th at 6:00PM.

Each year, approximately 4,000 people arrive at sunset with their handmade lanterns (typically made from recycled soda bottles) to take part in the parade that proceeds around the pond creating a beautiful display of colored light breaking up the darkness at the water’s edge.

For more information: http://www.spontaneouscelebrations.org

Photo Credit: Brian Talbot

Transitions in Thailand

August 3, 2010 / no comments

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On a recent trip to Thailand, I enjoyed a rare opportunity to experience traditional responses to local design challenges, unique architectural expressions of place. Upon arrival, one of the first things you notice is the very hot tropical climate. Then, as you explore, you start to notice the particular cultural responses to this climate – that there is a recognizable characteristic, developed out of necessity, present throughout regional design traditions.

There is a continuous theme of architectural techniques that respond directly to climate with a simplicity and completeness of expression, especially evident in visits to some of the many magnificent Thai temples.

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Approaching the temples, there is a sense of grandeur as bright sun shimmers off of the brightly colored tiles, among an array of sweeping roof structures and light exterior surfaces. The journey of enlightenment begins with this first glimpse of the temple complex, and continues inside with a smooth progression from the bright outdoors, through shady verandas, to serene interiors.

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The temples use deep overhangs and verandas to provide vitally important shade, in response to the direct sun and persistent hot weather. These elements mediate the tremendous brightness contrast, while at the same time, acting as a threshold to solemnize the moment of entering the sacred space.

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Inside, surfaces are defined by dark wood, in less reflective colors and textures. This transition has a phenomenological effect of coolness, and establishes your focus on the gleaming Buddha that reflects indirect daylight from the windows. The dazzling reflections emanating from golden surfaces are a beautiful visual expression of the Buddha’s spiritual magnitude.

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The traditional Thai temples are filled with only a subdued sense of natural daylight, which is an interesting contrast to contemporary thinking, but the dark walls and ceiling are not perceived as blank planes; there is just enough ambient light to pick up ornate, glossy details which define the structure. The effect, though subdued, creates an inspiring, pleasing atmosphere.

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During my travels in Thailand, there were many new experiences, but throughout them all, what I enjoyed the most was this collaborative expression of daylight and transition, and the harmony with which the local architectural style transcends necessity.

Photo Credits: Fai Dechavas (1,4), Amber Hepner (2, 5, 6), Truly Asia (3)

Photo of the Month: December 2009

December 7, 2009 / no comments

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As each winter season comes upon us, New England celebrates with holiday light decorations at Faneuil Hall Marketplace.

The promenade is lined on both sides with trees, transformed with thousands of white glowing lights that remind us of all the diverse holiday celebrations and traditions that make this season different from all the rest. The biggest tree is the traditional 87-foot-high Norwegian spruce, decorated with 15,000 white lights, as well as red, green, and gold ornaments.

Faneuil Hall is typically bustling with shoppers, diners, and entertaining street performers. As the sun sets, the holiday lighting really begins to shine. The overall scene that the lighting creates adds another layer of liveliness, stimulating your senses as you wander through the marketplace, admiring the sparkle and cheer of the season.

The holiday lighting creates a setting in which many people stop to admire, take pictures, or just gaze up as they are walking by, but in one way or another it defines that particular moment, that might otherwise be walked past. Lighting is dynamic and complex, yet sometimes the purpose is simply to pause and enjoy the experience.

Photo Credit: Amber Hepner / Lam Partners

Photo of the Month: November 2009

November 2, 2009 / no comments

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Autumn’s waning daylight gives way to seasonal celebrations centered on light. Spontaneous Celebrations’ annual Lantern Parade at Boston’s Jamaica Pond brings together a diverse community to celebrate the changing of the seasons on the fourth Sunday of October.

A sliver of moon, soft breezes from the south, and a few thousand celebrants encircle the pond in lantern light. Lanterns are, for the most part, homemade from two-litre soda bottles layered with diffusing tissue paper cut-outs, and each lighted with a single candle. The 1.5-mile wooded path along the pond is left largely unlit, allowing each lantern to contribute its own warm glow. Rarely has one footcandle* looked so lovely.

* Footcandle: A unit of measure of the intensity of light falling on a surface, equal to one lumen per square foot. Originally defined with reference to a standardized candle burning at one foot from a given surface!

Photo Credit: Amy & Salim

Photo of the Month: October 2009

October 13, 2009 / no comments

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It’s All Relative

Brightness, color, and contrast all play a role in any visual composition. This is especially true of lighted nighttime environments; the interplay of these three characteristics determines the quality and character of the lighted environment.

In the foreground of this image, on the right-hand side, is a brightly lighted mock-up of what is soon to be a prominent architectural feature of a new high-rise building under construction in Boston. The color-changing LED fixtures seen at the bottom of the image will highlight this building feature at different intervals, adding a playful element to the Boston skyline at night. The property owners will determine which colors to accent this element with, and therefore can control how subtle or dynamic this feature for different occasions. The use of color helps distinguish this lighted portion of the building from the sea of white light spilling from the windows of surrounding buildings in the skyline.

The overall brightness can be adjusted by dimming the LED fixtures. In the middle of the night, when most are asleep, the brightness can be reduced by dimming, giving a more subtle appearance than what might be desired earlier in the evening during prime viewing hours.

The contrast within a photograph taken shortly after dusk often produces the most striking images of lighted environments. The deep color of the sky enlivens the image, while it is the contrast between the sky glow and the dark silhouettes of buildings that defines the city skyline. A few minutes later in the day, and the sky will be too dark, the contrast is reduced, and the perception of the building forms is lost.

As designers we never want to use color or increase brightness just for the sake of doing so; more is not necessarily better. However, all of the lighted environments that we design must balance these characteristics – brightness, color, and contrast – and use them carefully to hopefully create architectural projects that become stunning images.

Photo Credit: Jamie Perry / Lam Partners Inc

Photo of the Month: September 2009

September 8, 2009 / no comments

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Back to School with Architectural Photography

How does one successfully photograph a piece of architecture? Do you need the widest lens available to capture as much as possible? Or the latest and most expensive digital equipment to produce the sharpest images? Sure, it helps to have the right equipment, but that is just the start.

Any successful architectural photograph should articulate and balance three key elements: form, color, and movement.

The forms being photographed define the composition of the image. The edge of a building, a row of windows, a pattern in the floor tiles… in 2D these elements are transformed into visual cues that draw our eyes around the image.

How the forms in an image are communicated to the viewer is enhanced by varying intensities of color, which in turn arise through variation in light quality and intensity. Brighter portions of an image bring out and enhance the shadows and silhouettes that occur elsewhere in the scene. Areas of contrasting light and darkness create interest and keep an image from looking gloomy or monotonous.

Dusk is the “magic hour” for taking pictures. As the sun sets below the horizon, the sky turns a rich shade of blue, clouds are transformed in orange and pink, and the colors of objects suddenly come alive. Under full sunlight, colors are washed out, but at dusk they become fully saturated and fascinating. Light from various directions begins to come into play as the daylight dims down and the electric lights come on. Well-placed lighting can reveal interesting details of architecture that go unnoticed in the daytime, and create hierarchy and structure in an image.

Movement can be anything that gives the impression of direction or fluidity. This could be, for instance, a curving wall that leads your eye across the image, or it can be something actually moving, like the trees in this image, which are blurred by the wind and the shutter delay of the camera. This tension between static and dymanic elements is often what makes an image breathe.

In this photograph, taken out on the second-floor terrace of the new Northeastern University dormitory, we pulled all these elements together to try and convey our work on the lighting design. The glow below the bench and the grain of the floorboards draw the eye diagonally into the scene to the multi-story lobby space beyond. The bright downlights and white ceilings form a smooth vertical element that eventually breaks the border of the image. A pattern of regular square windows beyond are accented by spill light catching the edges, giving depth to the saturated deep-orange façade. The deep blue sky in the corner provides a splash of complementary color. Windswept trees, lit from below in the planter beds sway gently, and the faceless person sitting on the bench gives the terrace a purpose.

Photo Credit: Nathanael C. Doak / Lam Partners

Photo of the Month: August 2009

August 3, 2009 / no comments

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One of my favorite local beaches is Coffin’s Beach on Boston’s North Shore. It’s a spectacular flat arc of sand about 1-1/3 miles long and, at mid-tide, about 120 yards wide. Here’s a thought experiment to illustrate the incredible adaptability of human vision. On a nice, sunny July day around noon, the daylight on the beach measures 10,000 footcandles. It’s a little uncomfortable without sunglasses, but I can read a newspaper with some squinting.

My beach towel is 30 inches wide and 5 feet long. Let’s imagine that I spread it out on the beach and collect the daylight falling on the towel at that moment. I come back at midnight, and spread that same “towelful” of daylight illumination evenly over the entire area of the beach, about 2.5 million square feet, more than 57 acres. That will give me enough light to still read the paper. Yup. The headlines are easy, the article text is a little slow, but I can make it out. Wanna bet? That towelful of light will give us about 0.05 footcandles over the entire beach, which is the ASHRAE/IES recommended minimum for a walk in the park.

So I can read the newspaper over an illuminance ratio of about 200,000 to 1. We can actually see over a still greater range. For just walking around, my eyes aren’t even trying hard at 0.05 footcandles. In fact, I still have some sense of color vision, and my colorless night vision is just beginning to kick in. In order to get my night vision to take over completely, I’d have to spread my towelful of light over a hundred Coffin’s beaches – almost 60,000 acres.

Photo Credit: Google