Sunday, May 10, 2020

St. John's Wort - Hypericum in reflected ultraviolet photography and simulated bee and butterfly vision II

Today some outdoor shots of that attractive yellow flower, a St. John's Wort - Hypericum sp. shot in reflected ultraviolet photography, simulated bee and butterfly vision. All shots were done at f8 in reflected ultraviolet photography using my "work horse" UV filter, the Baader-U filter, as well as my XBV filters for simulated bee and butterfly vision. Lens used was an interesting STEINHEIL 50mm I recently found with rather high UV transmission. Light source was sunlight.

[click on image to see a larger one]

Human vision:

Reflected UV:

Simulated butterfly vision:

Simulated bee vision:

Quadriptych of human vision, UV, simulated butterfly and bee vision (left to right, top to bottom):

Hypericum's outer petals strongly reflect UV around 365nm, whereas its stamens and pistil are quite darker, reflecting around 385nm, hence forming UV nectar guides for UV seeing insects. This is all invisible to us humans, but clearly visible to bees and butterflies. And all this gets nicely visible here, also in simulated bee and butterfly vision, using this surprisingly well performing 50mm lens.

I have written more about this flower HERE 

I have written about that lens HERE.

Stay tuned, more will follow on that fascinating subject...

More info on this very interesting field may be found on my site