[click on image to see a larger one]
Human vision:
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Reflected UV:
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Simulated butterfly vision:
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Simulated bee vision:
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Quadriptych of human vision, UV, simulated butterfly and bee vision (left to right, top to bottom):
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Sempervivum flowers have a distinct UV reflection, their petals have a dark center center line, the outside part is UV darker and all this gets nicely visible here, also in simulated bee and butterfly vision.
I have posted about this flower before HERE
More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos