NikonGear'23

Images => Nature, Flora, Fauna & Landscapes => Topic started by: bobfriedman on November 25, 2020, 00:07:49

Title: Gourd - UV stimulated fluorescence into the visible
Post by: bobfriedman on November 25, 2020, 00:07:49
So I was doing some painting with light and figured I would try some UV stimulated resonance fluorescence into the visible. I used a Nichia UV light with a U-340 filter to stimulate fluorescence in the second image.

Nikon D850, AF-S VR Nikkor 200/2G
25s f/13.0 at 200.0mm iso31
(https://pbase.com/bobfriedman/image/171238765/original.jpg)

Nikon D850, AF-S VR Nikkor 200/2G
61s f/13.0 at 200.0mm iso31
(https://pbase.com/image/171238761/original.jpg)
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: Akira on November 25, 2020, 04:40:25
Interesting find, Bob!

Apparently, the one in the middle fluoresces most vividly.  I wonder if you cast a rather narrow UV beam onto it.  It looks dramatic anyway!
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: pluton on November 25, 2020, 05:23:44
Lovely false color work, Bob.
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: bobfriedman on November 25, 2020, 09:47:31
Lovely false color work, Bob.

actually not false color.. true color taken in the visible by inducing the guards to fluoresce by stimulating them with ultraviolet light.
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: pluton on November 25, 2020, 23:05:26
actually not false color.. true color taken in the visible by inducing the guards to fluoresce by stimulating them with ultraviolet light.
Touché. "false color' implies the color being falsified in the photo process. In any case, thanks for accurately recording the far out colors that the UV light revealed!
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: JohnMM on November 26, 2020, 00:47:17
I like the pictures but I'm confused by the term 'resonance fluorescence'. I though that this describes the situation where excitation and emission energies are the same which is not the case here.
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: Erik Lund on November 26, 2020, 10:57:18
Very nice set of images side by side!Really impressive and creative approach ;)
Title: Re: Gourd - UV stimulated resonance fluorescence into the visible
Post by: Hugh_3170 on November 26, 2020, 12:42:37
Yes - you are quite correct John, e.g. the 254 nm UV resonance fluorescence radiation from the decay of the excited 6 3P1 state of Mercury to its 61S0 ground state  is a very good example of resonance fluorescence.  (Studied this one for my doctorate - a very long time ago I hasten to add!   :( )

I like the pictures but I'm confused by the term 'resonance fluorescence'. I though that this describes the situation where excitation and emission energies are the same which is not the case here.