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Lichen multispectral in closeup

Asher Kelman

OPF Owner/Editor-in-Chief
Klaus,

The UV reflection SEEMS so uniform, but is this just because you have a wide array of energies in the UV range?

It would be interesting if the UV might be refined with exaggeration of differences in absorption of the UV light or is it uniform a broad UV range of wavelengths?

Also does the reflected light get rotated or polarized?

Asher
 

Dr Klaus Schmitt

Well-known member
Asher, from my research the UV reflection using this filter and the way it is white balanced in a standardized way allows to differentiate coursely the "UV sub-bands", so here it gets obvious that this one type of Lichen reflects around 380nm. There is sometimes a polariznig effect, but I haven't checked this sample out yet.

 
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Asher Kelman

OPF Owner/Editor-in-Chief
Asher, from my research the UV reflection using this filter and the way it is white balanced in a standardized way allows to differentiate coursely the "UV sub-bands", so here it gets obvious that this one type of Lichen reflects around 380nm. There is sometimes a polariznig effect, but I haven't checked this sample out yet.

It could, perhaps be interesting to look at the inverse, principal UV absorption bands too?

I think it terms of nucleic acid and dividing cells or infection with viruses.


Also, is there any fluorescence?


Asher
 
I just wonder since in my chemistry upbringing it always was absorption that we had to answer to, as that [was] how we measured stuff!
Perhaps in Chemistry, absorption is the more interesting metric, based on the higher the amount - the more the effect of UV upon a substance.

Whereas one can imagine that, in photography, the relative amount of UV reaching the sensor is of greater interest ...

Ted
 

Asher Kelman

OPF Owner/Editor-in-Chief
Perhaps in Chemistry, absorption is the more interesting metric, based on the higher the amount - the more the effect of UV upon a substance.

Whereas one can imagine that, in photography, the relative amount of UV reaching the sensor is of greater interest ...

Ted
Thanks so much Ted for your comment!

Value that you are around! What are you shooting with these days?

True, one can get more to easily visualize what’s reflected. But we could compute what’s missing and get complete images with detail we wouldn’t otherwise identify!

I wonder whether some mathematics endowed photographer hasn’t explored this?

Usually when one thinks of something, it’s already been materialized in some form!

Asher
 
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