Focus lighting
Objects d’art, plants and display cases are the jewels of the office complex where lighting is concerned. They provide the designer witht he ultimate opportunity to add glitter and focus to the environment and make it come alive.
Without key (or accent) lighting a space can appear overcast, foggy. Add sunlight and the fog lifts. By creating contrast through the proper use of colors and quantities of illumination, the designer can generate that rare excitement we experience when a shaft of light penetrates a forest and strikes a green leaf or shimmers on the ripples of a pool. Painting, Photographs, Prints and Fabrics
Watercolors, oils, fabrics, color photographs and prints fall into the category of art forms that contain fugitive colors. Such works will fade and deteriorate if subjected to high levels of ultraviolet rays from excessive fluorescent lighting, high pressure sodium or metal halides. Designers who unknowingly or carelessly use these light sources may shorten the lives of the art they illuminate. Color distrotion is another potential drawback that the designer must avoid.
It would be unwise, of course, to illuminate the entire office with incandescent light because of the cost of operation. Also, one would be limited to working with one source color and a small palette, thereby reducing the design’s potential for variety and modulation.
An ideal solution is to use a mix of methods, for example by utilizing fluorescent, indirect metal halide, etc., as ambient light–thereby reducing energy cost. This bland pervasive type of illumination then serves as a perfect foil for the high drama that a designer can create with incandescent key lighting. Picture Lights and Wallwashing
There are several ways to light the paintings, photographs, etc., that hang on a wall. One is by means of picture lights cantilevered from the wall surface over the works. Another way is by wallwashing. Here the entire wall is lighted, and all objects receive the same intensity of light. Wallwashing requires a brightness differential between it and the surrounding ambient light of at least 3 to 1, and in some instances as high as 10 to 1.
Color of light is also critical. Again, ano contrast, no drama. If a warm incandescent key light of 2800 degrees Kelvin is used in combination with a warm fluorescent luminaire of 3000 degrees Kelvin for surround, the key light won’t “pop” the paintings. In this instance the intensity of key light would have to be increased or the wall painted a lighter color than the surround.
Tungsten halogen is an excellent tool for wallwashing because of its complete color spectrum, and its bonus of reds and blues. A glass cover reduces the small amount of ultraviolet present in tungsten halogen lamps to almost zero, and is required protection in the unlikely event that the lamp explodes.
Since its light source is small, it can be contained in a small luminaire yet still give good distribution. As a bonus it can be made shallow to fit under ducts and structures when recessed, or to present a modest silhouette when suspended.
Although fluorescent lighting can be used effectively for wallwashing, the initial investment is higher than for other methods. Also, its large assembly makes it less desirable than some other alternatives. However, if the choice is fluorescent key lighting or nothing (perhaps as the result of energy cost limitations), fluorescent is the better choice. The enhancement of the environment and resultant lift to the spirit is well worth the effort to make it work well.
R and PAR lamps will throw light on the wall when combined with a complex assembly of reflectors, but these tools, like fluorescent, are less desirable because of their size.
“A” lamps, used in an open reflector assembly, are another choice with drawbacks. This arrangement becomes ineffective within months because an unprotected reflector becomes filmed with dirt and smoke. Targeting
Another method for lighting art that hangs on a wall is to focus on the work itself with a unit that targets it. Today, possibilities are endless. I was lucky to visit showroom of Artbywicks, their large wall art were showing perfect. For instance, you can use a low voltage adjustable spotlight with a beam spread that just accommodates the subject. Or you can go to the other extreme of cost with a sophisticated theatrical objective lens assembly contained in the luminaire, surface mounted or recessed. By means of shutters, this method allows for you to frame the picture so precisely that it appears to glow from within. Only a very special subject, such as the portrait of the founder as a lobby focal point, would warrant the constant attention of maintenance personnel required for such things as the framing shutters and the aiming of the luminaire.
When focusing on an individual work, its predominant colors should determine the light source. If the colors are warm, a source such as incandescent is appropriate. If they are cool, one should choose a source that contains enough blue-green in its spectral distribution to render the buses effectively. Quartz, for example, has more blue-green than incandescent because the Kelvin temperature is a couple of hundred degrees cooler. Black-and-Whites
In an area where only black-and-white photos or line drawings are displayed, it usually preferable to light the entire wall. Not only is the presentation neater, but one eliminates the need to focus and refocus individual luminaires. Here is an ideal place to utilize fluorescent lighting, especially if lower operating costs are key.
Although track lighting, with wart-like appendages, is frequently used here, I particularly dislike it because of the busy, uncaring composition it presents. If you really need the kind of frequent flexibility track lighting provides, however, and if the architecture allows, the fixtures can be positioned in a slot above the ceiling plane so that the clutter is hidden from view. Reflections
When faced with lighting works of art covered with glass or which have specular or semi-specular surfaces (acrylic paint for instance), glare will be a problem unless you heed the tried and true rule “that the angle of reflection equals the angle of incidence.” If works are modest in height and hung at a normal position, in most instances you can avoid glare by aiming fixtures 65 degrees below the horizontal. Sculpture
When lighting a sculpture, the designer must decide how dominant the form is to be in the space. Should it be perceived as just a pleasant addition to the decor, or as a compelling focal point, with the eye drawn to it photo-tropically? To create impact, more light is needed–more contrast to surround.
Key lighting produces the modeling necessary to best perceive textural quality and shape. Fill light, in a ratio of about 4 to 1 between key and fill, enhances the form by allowing us to see into the shadowy areas, so we may better appreciate the artist’s every detail, every nuance.
Just how much light to put on a sculpture is determined by its reflectivity, as well as how much attention you wish it to draw. A dark bronze, for instance, will require a great deal more light to render it properly than white stone. A highly dramatic effect can be achieved by making the sculpture 10 times brighter than the surround. Plants
Techniques for lighting plants are similar to those for sculpture with a few extra considerations. Proper rendering of green leaves, which are prominent in most planting, is a major concern.
Light sources with cool color content in their spectrums show off green leaves as their best. Source with too much red will make the leaves appear lifeless.
Plants should be lighted in a way that will encourage growth. I recommend metal halide or color-improved mercury lamps not only because they render greens to well, but because they yield tremendous quantities of light with minimal energy consumption. This bonus allows your client to leave plants in place permanently, thereby eliminating the cost of hiring professionals to rotate them.
When it comes to flowers or foilage in reds and yellows, you’ll need incandescent lighting to “turn them on.” However if you are forced to illuminate greenery with this source, because of ceiling limitations or initial cost restrictions, add a pale blue filter to achieve high drama. Combinations of metal halide and incandescent are extremely effective. Display Cases
Display cases, to present company products, provide the designer with the chance to create colorful and exciting focal points in the office. Products are, after all the real “object d’art” of a company and their display should be recognized as a prime opportunity to present the company.
All of the Suggestions for creating drama with art and plants–using key light for modeling and fill light for subtle shadings–apply to objects displayed in cases. Showcases are usually lighted in two ways: illumination is pumped down into the case from the ceiling; or it is contained in the case itself.
When light is projected downward, one must be certain not to allow it to reflect off the glass or plastic case into the eyes of the viewer. The reflection/incidence angles apply here, too.
Frequently one sees displays of beautiful gems in jewelry shops, even in museums, where regrettably a single light source (such as fluorescent) is loaded above a shielding louver or lens installed in the top of the case. Diffuse lighting of this kind is devoid of modeling and the sparkle that creative highlighting can bestow on metal, pottery, and other specular surfaces. The addition of something as simple as a small incandescent spotlight will provide the fire–the glitter, the shadow.
It is also a mistake to use a single spotlight to illuminate a case. Not only will it create distracting shadows, but it can turn three-dimensional objects into two-dimensional ones. Less Is More
To create excitement the designer must utilize the available tools judiciously. Key lighting will only work when used with restraint–reserved for the special object, the special happening.
A successful lighting effect never announces itself as such. I will forever carry with me the memory of a display at the Metropolitan Museum of Art in New York, in which a narrow spot called out a single unicorn in the center of a large hanging tapestry. The difference in lighting quantity between unicorn and surround was extremely subtle. That subtlety created a special drama.