[click on image to see a larger one]
Visible light image:
UV image using Baader-U filter (approx. 320-395nm, effective peak approx. 375nm):
Simulated bee vision image using experimental XBV filter:
It is quite interesting to notice that Winter Aconite with UV reflection around 365nm and Crocus reflecting UV around 380nm are competing for bee's attention. I wonder which one wins, there haven't been many bees aroudn, mainly bumble bees, but I guess the Crosus does. 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...