Black eyed susan normal and fluorescent images

This is an example of the complexity of the interpretation of the fluorescent image of a flower illuminated with UV light. It is not the UV image of a flower as it would be seen, eg, by bees. The camera is actually completely insensitive to the illuminating source and sees only fluorescent light.

The left image is the flower (Thunbergia alata) in white light and on the right is the same flower illuminated by a 368nm UV LED which is filtered to extinguish any visible light - ensuring that the flower appears solely as a result of fluorescence.

The spectra above show:

Green line: the transmission of the yellow/orange petal
Light and dark blue lines: The fluorescence of the petal under 368nm UV (the light blue line shows the use of a yellow filter before the spectrometer to remove any 2nd order UV light which would appear as a bump at 740nm.)
Red line: the petal fluorescence excited by a 404nm violet laser.
Thin black line: the 404nm excited fluorescence of chlorophyll in a Ficus leaf.

The rising spectrum (blue lines) below 530nm is responsible, along with the red band, for the purple/pink seen in the fluorescent image.

The presence of what appears to be chlorophyll emission in the blue line spectra is curious since it is absent in the 404nm laser excited spectrum (red line). I know that the laser is quite capable of exciting chlorophyll fluorescence but I'm not sure why it fails to do so here. Is it because the signal is dominated by the non-chlorphyll fluorophore? And where does the chlorophyll reside in the petal - it is not obvious from a microscopic examination?

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