Okay, this is going to sound a bit weird. I was hiking last weekend and saw this bird with the most incredible, almost metallic blue feathers. I tried looking it up when I got home, but every source seems to describe the color differently. It got me thinking about how we actually perceive and categorize something like iridescence. Is what I see as a shimmering blue the same thing you see, or is our individual perception of structural color totally subjective?
That sounds breathtaking I can almost feel the light playing across those feathers and the word iridescence seems right even if it only hints at what you saw.
Iridescence in birds comes from nanostructures that interfere with light not from pigment so the hue shifts with angle and sun position which is why different guides describe it in different ways.
You might be misplacing the idea by expecting a single fixed blue The shimmer is a moving target depending on how you hold your head and how the light hits the feathers.
I get why the question feels subjective since our eyes do the tagging but there is a real physical process up there that makes the shimmer possible even if our naming varies.
Maybe try reframing the issue around how we categorize what counts as blue in a mood or moment rather than asking if perception is the same for all brains.
If you have a moment bring a camera next time and compare a static photo to your memory does the metallic sheen survive or disappear depending on angle.