Friday, February 24, 2012

Don't Try Violating the Maier Principle (Part 2)

There is no good excuse for art to remain in the shadows, because excellent lighting is now both easy to afford and fairly simple to install. There are some absolutely wonderful high-end illumination systems out there, but you need not go that far to achieve a powerful result. There are many ways to go about it, but for my own studio/gallery presentation, and in my on-the-road art show booth, I use miniature quarz-halogen spot reflector-type bulbs (type GU10 in either 35 or 50 watt versions).

While these bulbs used to be fairly pricey, they are now inexpensive (only two to three dollars apiece) and easy to incorporate in a lighting setup. This is an excellent technology to use, as they are truly "broadband" devices and their continuous optical spectra will reveal all of the nuances of color gradation and subtlety in the artwork. Further, the built-in metallized glass spot reflector directs nearly all of the light onto the art itself, not wasting it in illuminating the room in general.

GU10 bulb, front
GU10 bulb, rear

Although CF (compact fluorescent) technology is a wonderful way of saving conserving electrical power, it is a very poor way (at least with the current devices available) of illuminating fine art. The problem is that the optical spectra of the light produced is not continuous, but broken into discontinuous spectral "bands" of light. This can then cause what is called "metamerism" when a work is viewed under it. Metamerism is when the colors of a material (the various pigments in a painting, for instance) appear a different color than expected under a different light source. If you want your art to appear as the artist intended, a broadband light source is essential. CFs are also a fairly "extended source," rather than a small "point source." This makes it such that the CF's light output cannot be effectively redirected to light only the art (like a spot light).

Current LED light sources, as expensive as they are, also have problems with narrow, discontinuous bands. Until this technology is improved in this area, LED lights should be avoided, too.

Miniature incandescent sources (like the  GU10 bulbs I mentioned previously) can be used in a vast array of lamp types and configurations. Your local home improvement center is generally a great place to find these fixtures. They are available in multiple-lamp track configurations, single ceiling mount fixtures, or even in table-top lamps. The main thing is to make sure that you have enough light on the subject. If it turns out that you install lighting and then think you might not have enough, you can always add more fixtures. Most of these fixtures are fairly simple to install by most home owners.

Various GU10 Spot Lighting Fixtures in Track
The only caveat in mounting these lamps is that you don't place them so close to the art that they significantly heat it up. To find out if you have placed your lighting too close to the art, place the back of your hand immediately in front of the illuminated art at its closest point to the lighting. You should NOT be able to perceive any heating of the back of your hand, due to the lamp. If you have the slightest sensation of heating of your hand, either move the art slightly away from the lighting, or move the lighting farther from the art. Generally, a single 50 watt  GU10 type halogen bulb should be no closer than about two feet from the closest point of the art.

Your art is "a terrible thing to waste." Give it the light that it's due. As an optical engineer who I worked with for many years was fond of saying: "You can't violate the 'Maier Principle,' which, in short, states– 'if you ain't got enough photons, you ain't gonna see it!'

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