Illustrating Metamerism with a Digital Camera

Daylight

I can remember very frustrating times in my shop when I worked like crazy on a refinished piece of furniture to match the color on a sample piece of furniture, only to take the refinished piece to the client’s house and find that it didn’t match. But it matched perfectly in my shop I would meekly explain.

I didn’t understand the phenomenon of metamerism.

The problem was that the light source in the client’s house was different then the light source in my shop, and the light source makes a big difference for how your finished wood projects appear. It’s important to be aware of this if you are working on a project in your shop under one light source and then moving the project to another light source.

Digital cameras have made my life of teaching so much easier. I realized that using one of these cameras, I could easily show the difference a light source makes. I set the white balance on my digital camera for daylight and took the first picture outdoors in the shade. Then, without changing the white balance, I took additional pictures indoors under the cool-white fluorescent lighting I use in my shop, the full-spectrum fluorescent lighting I use in my finishing area, and finally the incandescent lighting in my house.

Cool white fluorescent

Full spectrum

Incandescent

Notice how the cool-white lighting brings out more green in the stained mahogany, the full-spectrum lighting, which I think is best for a finishing area, produces a color that is closest to natural daylight and the incandescent lighting brings out more red tones. This is what you should expect when you move furniture from one light source to another.

– Bob Flexner