Why does paint look good in the store and bad on your walls? It's science

You went to the paint store, looked at the color charts and even tested hues in a virtual 3-D display with your favorite trim. So why did your living room look so awful once the paint dried?

Maybe you should have consulted a color scientist.

"We study the science of everything involved in capturing, reproducing and perceiving color," said Mark Fairchild, a professor at the Munsell Color Science Laboratory at the Rochester Institute of Technology.

"Think of an iPhone: Its camera has to detect color stimuli, the software has to process and store that information, and the display has to re-create those stimuli for the observer. Color science touches on all those steps."

Science helps to explain why colors seen at a paint store or on a paint chip can look so different at home. The size of a color sample, the lighting in which you view it, and the colors of other walls and objects nearby all have an effect, Fairchild said.

"The two big issues are lighting and context," he said. "Painting a 3-foot-by-3-foot patch on your wall and letting it dry will tell you a lot more than just looking at a color wheel in a paint store. At least then you have the right lighting and some of the context and geometry of the surroundings."

Science also explains why the time of day has such an effect on a room's colors, Fairchild said.

Lighting, in fact, is fundamental to the perception of color, he said.

"Take an apple," he said. "The apple is red, but that does not mean that it only reflects red light. It reflects light of all wavelengths. It is just that it reflects red light more strongly than, say, blue or green light. As the balance of the illumination changes through the day, the relative amounts of red, green and blue light reaching our eyes after reflecting off the apple will also change."

He offered an example from his own home: One evening, when his family sat down for dinner by candlelight, which emits a yellowish tone, their young daughter began crying, because her beloved yellow mac and cheese looked white. He switched on the electric lights, which emit a whiter tint, and voilà: The mac and cheese looked yellow again.

One of the trickiest parts of the perception of wall paint colors, he said, is accounting for how they are affected by the lighting and paint colors of an adjoining wall or room.

"Inter-reflections across neighboring walls have a big effect," Fairchild said. "Let's say you pick a slightly yellowish off-white paint that looks pretty neutral in the store. When you paint a room in that color, that yellow tint will illuminate an adjacent wall, making it look more yellow. The effect is amplified as you look into a corner with both of those yellowish walls reflecting off each other. It's the same reason that the petals of a red rose look so colorful in the center."

"Colors and combinations of colors that are pleasing or jarring are not universal," Fairchild said. "One of my former students used to like to say, 'Those colors make my teeth hurt!' But a color that infuriates me might calm you, because we might have different historical or cultural contexts for it."

Interior designers who specialize in color selection agree that subjective preferences play a major role in the perception of colors.

"Color is science, but it's also math, it's art, it's psychology," said Peggy Van Allen. She worked for Sherwin-Williams in color design and marketing before becoming an independent color consultant, and now serves as the president of the Color Marketing Group, which releases annual color trend forecasts. "You shouldn't be intimidated by the science. Choosing colors should be fun."

Her pet peeve, Van Allen said, is how the newer lightbulbs affect the color of a room "The LED bulbs are made to last longer, but they often have a cold, blue tone that almost looks fluorescent," she said. "That will make all the colors in your room look different. You have to pay attention to it when choosing lights."

Additionally, Laura Rugh of Rugh Design, a color-consulting firm, cautioned against relying solely on displays shown on computer programs when choosing a color.

Fairchild agreed that relying on computer imaging — or even on the lessons of science alone — can be limiting.

"3-D graphic imaging can be quite accurate, but it's not perfect," he said. "A combination of computer imaging and an actual patch of paint on your wall is probably best. And adding the advice of a designer or painter who has lots of experience will also help."

Still, he said, don't leave the science behind. For instance, the supposed emotional influence of certain colors — calming blues or invigorating reds, for example — is mostly based on hearsay.

"There is a small amount of scientific evidence to support some of the affective influence of colors," Fairchild said, "but if anyone tries to tell you that it's absolute, that is hooey. The effects are quite small and very dependent on the individual."

For example, a bright tone of pink known as either "Baker-Miller Pink" or "Drunk Tank Pink" has been touted for decades as having a calming effect on prisoners or psychiatric patients.