Today no flowers shots, but instead testing a f3.5 / 20mm wide angle lens for usefulness in UV and BV, for reflected ultraviolet photography using my "work horse" UV filter, the Baader-U filter as well as my XBV filter for simulating bee vision. Light source was sun. All shots were done at about f3.5.
[click on image to see a larger one]
Triptych of human vision, UV and simulated bee vision (left to right):
Well, its gets obvious that this lens has a useful UV transmittance and is quite sharp also in ultraviolet light.
Stay tuned, more will follow on that fascinating subject...
More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos