Sunday, March 2, 2008

Primula II ... UV induced visible Fluorescence

So today a flower fell of that beautiful Primula plant. I had bought that for my balcony, since I needed some colors around me after a long a dark winter, which is finally over here in Weinheim / Germany

I grabbed my camera, attached a long extention tube, plus that tack sharp UV Rodagon 60mm lens. This following shot was done using a tungsten cold fiber light: [as usual, a click on an image opens up a larger view]

So if we switch from visible light to UV light, in this case using my 365nm Nichia UV LED flash/lamp, we will see the pollen light up blueish / greenish and also the colors of the flower petals change. I had to remember to use a UV stopping filter in front of the lens, in this case the 2" Baader UV/IR Cut filter, which also stops IR light very efficiently, needed for modern DSLRs due to their very high IR sensitivity. This is the result now, called UV induced visible fluorescence, commonly called fluorescence [there are other forms of fluorescence, too, like UV fluorecence, IR fluorescence just FYI].

So lets look a bit more in detail to these wonderful bright blueish/greenish lighting up pollen, first in visible light...

...then using UV light which stimulates flourescence. These shots need to be done in darkness, since that effect is quite weak and needs long exposure times:

So I hope you enjoyed having a look at a flower using UV induced visible fluorescence!

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

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