Independence Day bouquet -- Alpine thistle, daisy chrysanthemum, button chrysanthemum, spray rose. Flowers courtesy of Sturtz and Copeland Florists and Garden Center, Boulder, Colorado.
7 Comments
RobLL · 4 July 2010
As any gardener would note the problem is always to get a true blue. Oddly enough this also holds in the animal world where blue, at least in birds, comes from refraction of the surface of the feathers. Anyone know why 'blue' is so difficult?
I'm not quite sure what the implications of us true blue Democrats might be.
That's curious. Blue occupies a healthy portion of the visible spectrum, and many insects can see into the ultraviolet, so you would expect a healthy reflectance in the blue portion of the spectrum. Maybe it is mixed with red or violet.
At any rate, you can always do it this way.
... blue, at least in birds, comes from refraction of the surface of the feathers.
Mostly not refraction, I think, but interference from stratified feathers.
fnxtr · 4 July 2010
Happy birthday, neighbours. I hope I look as good when I'm 224.
Mike Elzinga · 4 July 2010
Matt Young said:
Mostly not refraction, I think, but interference from stratified feathers.
Indeed with grackles, hummingbirds, and a number of other birds with rich, deep coloring, slight changes in the direction of bright sunlight makes the colors change.
Grackles look purple in some kinds of lighting and jet black in others. The ruby throated hummingbirds that come around our feeder change color even as they come in for a landing on the feeder. The flashing of their ruby bib appears to be a refractive effect.
The flashing of their ruby bib appears to be a refractive effect.
No, it is red because of interference colors -- think of Bragg reflection or multilayer films.
When I was in college, I heard a colloquium by the physicist who was apparently the first one to explain why the hummingbird was colored even though there was no pigment. All I remember clearly was his closing line: "I myself heff never seen one, but I know exectly why zey are colored." At least, I think that's how he sounded.
Karen S. · 4 July 2010
I just wish my blueberry bushes would start producing tons of blueberries.
7 Comments
RobLL · 4 July 2010
As any gardener would note the problem is always to get a true blue. Oddly enough this also holds in the animal world where blue, at least in birds, comes from refraction of the surface of the feathers. Anyone know why 'blue' is so difficult?
I'm not quite sure what the implications of us true blue Democrats might be.
Matt Young · 4 July 2010
fnxtr · 4 July 2010
Happy birthday, neighbours. I hope I look as good when I'm 224.
Mike Elzinga · 4 July 2010
Matt Young · 4 July 2010
Karen S. · 4 July 2010
I just wish my blueberry bushes would start producing tons of blueberries.
fnxtr · 4 July 2010
oops. 234. Heh.