Inspired by two of the masters—Brandston and McCandless—the author offers a framework for honing the design process to improve the visual environmentBy Markus Earley
We have all experienced it and we’ve all had a response. I am referring to one’s reaction to less than good lighting, of course. Think about it. We have all experienced architectural spaces wherein something about the lighting is not quite right. It could be any of the following issues, to name a few: appearance, color quality, controllability, emphasis or lack thereof, flicker, harshness of shadows, lack of shadows, illumination levels on horizontal and/or vertical surfaces, luminaire placement, proportions and/or scale. Any of these issues can be perceived as, I’m going to say it: bad lighting.
We have all done it: squinted, to limit offensive glare. This is an involuntary reaction when pupillary response cannot mitigate excessive brightness. Our eyelids and our hands (or a baseball cap) help protect us from glare; like when one falls forward, and the hands are instantly extended.
No jury required, we are each able to judge and say, “I do not like” this, or that, aspect of the illumination, even if the reason(s) cannot be articulated. Our reactions to bad lighting indicate that something is out of balance with what we need/desire from a lighting system. The term: Koyaanisqatsi (koy·aa·nuh·skaat·see) comes to mind. In the Hopi language, Koyaanisqatsi means “life out of balance.” Indeed, when elements in our lives are out-of-whack, the results can range from mildly disappointing to completely disabling.
How can this be? LED technology can deliver more lumens for less watts than any other (commercially viable) electric light source, is spectrally tunable, diminutive in scale and wirelessly controllable. And there is terrific software that can render architectural lighting with photometric accuracy. All true, but these attributes and tools do not ensure good lighting from the viewpoint of the end user. Elements of bad lighting can occur when all of the variables that should be considered during the design process are discounted, overlooked or ignored.
Plus, LEDs have a few characteristics that are distinctly different from other light sources:
- LEDs are inherently directional. Each diode projects light in a conical shape of approximately 110 deg. Each LED, when interrupted by an object, will cast a shadow. LEDs are a directional point source. An array of bare LED chips will project a multiplicity of shadows. Incandescent, tungsten filament sources (A-lamp, etc.) are omnidirectional, like a candle, disbursing light in all directions, except through the base; a true point source. PAR/MR/R lamps are directional point sources because they have an integral reflector surrounding the filament capsule. Fluorescent sources (gaseous in nature) are considered an area light source with toroidal distribution: omnidirectional in cross-section, but less than omnidirectional parallel to the luminous tube.
- LEDs do not color-shift when dimmed. They just emit less light of the full-on color. Incandescent sources color-shift warmer when dimmed. And fluorescent sources actually color-shift cooler when dimmed. Since incandescent was the first commercially viable electric light source, we have come to expect a warm-shift when any electric light source is dimmed. This is why dim-to-warm technology, which utilizes different color white LEDs, sophisticated circuitry and a specific driver (power supply), was developed. It is also why dim-to-warm LEDs have lumen output limitations (a function of thermal management) and require a specific dim-to-warm driver and/or compatible dimmers, which can increase cost.
In addition, beyond all of the visual factors, there are also non-visual factors; because we now know that ipRGCs (intrinsically photosensitive retinal ganglion cells) in the eye help maintain our circadian biology, when stimulated by specific wavelengths of light that are transmitted, non-visually, to the brain.
Sheesh! No wonder there’s no simple recipe for good lighting, or as a college student once asked, “Isn’t there an app for all of this?”
Answer: “Yes, as a student of light, the best app is located between your ears.”
In other words, the lighting design/thought process must occur in order to yield positive, holistic results for the people that live, work and play on the Shakespearean stage we call architecture.
Naturally, there are many books and educational institutions that offer lighting design curricula, and the IES has many design-oriented offerings on their eLearning portal. One IES course, apropos because it’s about the inherent goodness of light, the design process and the communication thereof, is called: “A Second Language of Light,” by David Warfel,1 wherein he says: “The why is more important than the what in this new language of light,” and to “Ditch the FC, CCT and CRI (technical jargon) when talking to clients.” [See companion LD+A magazine article: “Plain-Spoken Approach,” February 2021.]
Indeed, Warfel’s essay is refreshing because its “five promises of light” imply that the specifier understands the human factors of architectural lighting, and that technical data, such as light level calculations, are merely tools, to verify lighting performance in support of the architectural lighting concept. This echoes words of wisdom by the late William Lam, “Lighting design is about light and not engineering. You have to understand about light and the physics of it, but mainly, it’s about having a vision.”2
Inspirational! But not every project has fascinating architectural features, or a budget for layers of lighting equipment, or for a lighting design consultant. It can be a challenge to conceive a grand vision for the lighting before the necessary technical requirements—all those acronyms—take over the process and another rote RCP and Lighting Schedule are generated.
To help remedy this, the following are some plain-spoken definitions, questions, truths and practical considerations—a conceptual lighting design framework, inspired by my first lighting mentor Howard Brandston,3 and his mentor Stanley McCandless4—that one can ponder throughout the design and construction process, to remind oneself of what is important and why, so that in the end, the services provided result in an improved visual environment, regardless of project budget.
- Conceptual Definitions
Light: Combine the art and science of light with four words—Visually Evaluated Radiant Energy. Every waking moment, we make decisions based on what we see and experience. Most of our sensory perception is visual information. Clearly, the quality of the visual environment matters.Circadian-effective light: Specific wavelengths of light, which when transmitted to the brain via visual and non-visual pathways (cones, rods and ipRGCs) at sufficient energy level, for sufficient duration, entrain and maintain our circadian clock, which in turn affects overall human health.Lighting design: A series of planned experiences involving people and space. Imagine every type of end user and the visual itinerary that they will experience as they move throughout the space(s) and interact with others over the course of time. “What is it you wish to see?”5 The answer to this question, when pondered on multiple levels, can open the door to a world of lighting possibilities.
Control: “Control of the light illuminating the acting area, as for all other lighting, involves the control of intensity, color, distribution, and changes.”6 Begin thinking about how the light will need to be adjusted on day one! Light and how it can be controlled/manipulated should be a singular thought process. Visualizing what a project will look like at different times or on different occasions can help establish control concepts and inspire luminaire selection. When a project comes to life in your mind’s eye, design decisions flow naturally.
- Qualities of Light
Intensity: The visual brightness of a light source, a reflected image thereof, or of a pattern, or a glint of light reflected off any surface or object.Distribution: The manner and direction, or lack thereof, in which light enters a space, or is emitted by light fixtures, or lighting elements within a space. Think beyond NEMA beam patterns and terms like spot/flood, and up/down. Imagine scenes such as: crisp autumn sunshine, brightening overcast skies, dappled sunshine on a freshly cut lawn, dramatic highlights and shadows on a jagged rock, the sparkle of a theater marquis, a favorite scene in a movie, etc. Reverse engineering the desired distribution can inspire light source and luminaire selection.Color: “Ordinarily the face of the actor should appear normal.”7 Naturalness, a warm glow, a cool cast, all fall within the normal range of “white” light, as evidenced by daylight from sunrise to sunset. The desire to appear normal is universal, thus the wide range of white LEDs. We have no built-in reference to “white” in our visual system. We adapt to the dominant light energy within a space. Think of warm sunlight from the south vs. cool daylight from the north (in the northern hemisphere). Remember, in order to perceive the natural color of an object, like a ripe lemon, the light source must contain the corresponding wavelength of light (yellow, for a lemon) within its spectral power distribution. And to depart from normal, or call attention to a particular material, or object, the use of contrasting, or colorful light, of sufficient quantity, will cause that object to stand out. Naturally, the color(s) of object(s) will influence decisions about the color(s) of light to be used. Mock-ups are an important part of the lighting design process. Ask where and how color will be used in a project—highlighting colorful elements, features or patterns could be an important aspect of the lighting concept.
Change: Daylight is not static, and neither is electric lighting. The notion of change in architectural lighting can occur in many ways: From occupancy/vacancy sensors to creative manual switching, to full range automated dimming, modulating light output in response to the visual needs of people is an obvious example. Change can also be what people experience as they move through a series of spaces with different lighting and/or spatial conditions. The ability to change, however subtle or drastic, is an essential quality that contributes to the success of any lighting project.
- Functions of Light
Visibility: We need light to see, but the amount needed depends on the visual task, duration, and other contextual factors such as contrast, foreground vs. background, etc. Visual comfort is an important factor, because although we can see in all sorts of visual environments, those that are uncomfortable due to quantity or quality of light cannot be tolerated for long periods of time without negative effects. Philosophically—no light; no space. Light reveals the truth, but we can be deceived by our visual perception of reality. Plato’s Allegory of the Cave is a timeless example.Form:
Light can reveal or obscure three-dimensional forms. Position, angle of incidence, and quality of light being thrown yield different results. Illuminate a cube from different positions and angles, with various light distributions and degrees of diffusion, to learn what these conditions look like.Composition: Every element in an architectural space contributes to and results in the visual composition that is experienced by others. For lighting, this includes the appearance, color(s), hierarchy, order, pattern(s), proportions and scale of the lighting equipment, as well as the visual effects emitted by that equipment. Pay attention to architectural patterns and details, as they typically offer clues as to how the lighting can be composed.
Atmosphere: Every architectural space will evoke a particular mood or attitude in its occupants. Lighting contributes significantly to one’s sense that the whole is greater than the sum of its parts. And now, with our knowledge of circadian-effective light, mood also means health and wellbeing. Ask about the intended atmosphere at the outset of every new project, as knowing this can inspire lighting concepts.
- Practical Considerations
Imagine any architectural space. Within this space, there will be limitations with respect to where electric lighting equipment can be located, which in-turn will affect how light can be applied within that space. Consider the “where” and “how.”
Where Electric Lighting Can Occur:
Location: Where and how lighting equipment meets/attaches to the building, or to architectural elements within.
Source: What specific light source(s) and form-factors such as: linear, chip-on-board, bulb, etc. and characteristics such as: output, color, etc., make practical sense for each potential location.
Distribution: What specific distribution(s) make sense for each potential location and source.
How Electric Lighting Equipment Can Be Applied:
Supplemental: Lighting equipment, typically utilitarian in nature, which is surface or pendant mounted, or recessed into architectural surfaces, such as: accent light, downlight, strip light, task light, track light, troffer, wall bracket, wallwasher, etc.
Architectural: Lighting equipment that is built-in to the architecture, often resulting in a symbiotic reliance on one another. Examples: indirect light cove, ceiling dome, linear light slot in ceiling and/ or wall, nose of stair tread, toe-kick light slot, etc.
Decorative: Lighting equipment that is ornamental in nature, and/or expressive in form, shape, luminous quality, etc. Examples: ceiling light, desk lamp, floor lamp, strip light, wall sconce, etc.
*Categories may be combined—Example: Indirect cove light with edge-lit glass at top of cove lip.
As Brandston writes, “The simplest defining characteristic of lighting, yet perhaps its greatest mystery, is the process of learning to see… By drawing, speaking and writing our ideas, we increase our chances of communicating clearly… Put people in all your sketches—they might remind you to think about lighting (for) them.”
References
1. David Warfel, founding designer of Light Can Help You
2. William Lam
3. I spent 1981-88 at HBLD my mentors: Chou Lien, Hayden McKay, Robert T. Prouse, and Gene Stival my lighting professor at Pratt Institute.
4. Stanley McCandless, author of “A Method of Lighting The Stage”
5. Howard Brandston, author of “Learning To See, A Matter Of Light”
6-7. Stanley McCandless