These shots were done using a long extention tube, a UV Rodagon 60mm and a Baader UV/IR Cut filter to suppress the UV exciting light source (Nichia 365nm UV Led lamp/flash). Let's have a look at a green leaf here: [as usual, a click on an image opens up a larger view]
So what do we see here? A mix of blueish fluorescent emitted light, mainly from these little hairs on the surface of the leaf and from the stomata which allows the leaf cells to exchange gases (Carbon Dioxide and Oxygen) with the surrounding atmosphere.
The reddish NIR flourescence seem to come from deeper inside the cells, no wonder actually, since it is a reaction of the chlorophyll deep within the plant cells (contained in the cell chloroplasts)!
Sigh - the ever present lint! Here now a shot from the middle of the leaf:
So I hope you enjoyed that high resolution journey to a Primula leaf!
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