[click on image to see a larger one]
Diptych (left to right): Human vison, reflected UV (Baader-U filter):
This attractive bird has iridescent feathers with a metallic magenta shine around his throat, chest and back, which reflect at maximum under a 45 degree reflection angle, however it also reflects UV quite strongly, peaking at around 365nm (shown as yellow) and to a much lesser quantity around 385m (shown as purple), invisible to us humans (but made visible here using special photographic methods), and all this gets nicely visible.
HERE is more about bird vision and how to simulate what birds might see.
Stay tuned, more will follow on that fascinating subject...
