[click on image to see a larger one]
Visible light image:
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UV image using Baader-U filter (approx. 320-395nm, effective peak approx. 375nm):
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Simulated bee vision image using experimental XBV filter:
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Winter Aconite has a prominent UV pattern, its center (anthers, stamen) is UV dark, and the petal ground seems to have some highly reflecting spots radially centered around the stamen. This older quartz fluorite lens is reproducing this quite well and all that gets nicely visible.
Stay tuned, more will follow on that fascinating subject...