Saturday, July 9, 2011

[UV] UV color of a flower leaf

Today about why leaves do have some false UV color when shooting reflected UV. So a quick reflectrometric experiment sheds some light into that, here using a Rudbeckia hirta and a Rudbeckia fulgida leaf and comparing them with reflected UV shots.

[click on images to see larger ones]

Standardized reflected false UV "colors" according to the previously described "UV color palette" related to wavelength.

Standardized false UV color normal and high intensity palette:

The R. hirta leaf on the left shows some greenish/grayish reflection with some violet on it depending on angle. The spectrometeric result reveals, that indeed the highest UV reflection is in the violet sub UVA range, wheras there is also some in the yellowish/brownish sub UVA range, but only a little reflection in the greenish sub band.

The R. fulgida leaf on the right shows some greenish/yellowish reflection and not much angle dependency. The spectrometeric result reveals, that it has quite an even UV reflection, which reaches quite deep into the UVA range to about 310nm and has proportionally a higher green / yellow content than R. hirta.

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

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