Color terms

Jane McGary
Mon, 20 Sep 2004 17:28:48 PDT
Lee Poulsen's explanation was very interesting and clear -- a good example 
of a scientist or engineer who knows how much information a general 
audience is likely to want!

When we look at flowers, we're seeing more than the color effects Lee 
discussed, because the surface of a flower petal is not as flat as a piece 
of paper or a monitor screen. There's a discussion of this in the 
forthcoming NARGS Rock Garden Quarterly in an article by Alan McMurtrie on 
hybridizing reticulata irises. He points out that the surface cells on the 
iris petals are of different 3-dimensional shapes depending on species or 
hybrid clone, and that the way the light "bounces" back and forth between 
the raised pigmented structures affects the way the human eye perceives the 
colors, because the light "picks up" extra color as it is refracted, if 
that's the right word, multiple times.

Another writer commented that the light under which we view a color sample 
affects what we see. This is an effect well known to anyone who deals with 
fabrics, in particular. You have to take your fabric where you can see it 
in daylight in order to perceive it correctly. (Some kinds of artificial 
lighting mimic daylight more or less effectively.) I've also read that 
flower colors are affected by the angle of the sun at different latitudes, 
so that the same flower would appear different colors in, say, Arizona and 
Toronto. I think a lot of flowers in the blue-pink range look better in 
diffuse sunlight than in brilliant sun,  while bright reds tend to look 
better in strong sun, but this is just a personal reaction.

Jane McGary
Northwestern Oregon, USA

More information about the pbs mailing list