I have some lichen observations with a UV flashlight, like this one with apparently two types glowing in different colors.
And while checking out the lichens, I chanced upon the discovery that Paronychia argyrocoma stems also fluoresce in an eerie bluish color. Polyphenolics or similar maybe?
The flashlight used had 365 nm UV emission.
I think that bluish color is from the tiny hairs of stem. Hairs on the plant reflect UV.
“Many plants have pubescence designed to provide a tiny bit of shade to reduce the temperature of the leaves and stems and protect the leaves from losing too much water from transpiration.”
For example: UVIVF Feather Cactus (Mammillaria plumosa): https://www.inaturalist.org/observations/105420672
I have less UV photos than I’d like; I need a better UV flashlight, the one I have ATM isn’t powerful enough to overpower daylight
But still, UV and mushrooms are a great combo
really want to do this underwater! anyone with experience conducting UV observations in the water?
I took some UVIVF pictures of crabs and shrimps before, didn’t turn out good.
I found out later, for underwater UVIVF photography, you can’t use real UV light, just regular blue light. https://nightsea.com/articles/blue-light-for-underwater-fluorescence/
During a cold lonely night on the dunes, I was trying to set up this shot:
And while I was fumbling with my flash, a white-lined sphinx flew right over to my UV flashlight, which I’d left turned on:
So kind of an accidental twofer there!
I don’t dive or do underwater photography, but when tidepooling at night (be careful!) you can use UV lights and find some rad fluorescence, like https://www.inaturalist.org/observations/17853484 and https://www.inaturalist.org/observations/141586746
White-lined sphinx really likes UV light!
I took an UV bee vision picture of Fringed Bluestar (Amsonia ciliata) earlier this year, and the main pollinator of A. ciliata is Whitepline sphinx.
I saw one flying around the flowers.
I haven’t tried, but you could paint a paper with spinach juice, let it dry, place something that has an interesting shape, expose to sunlight, and voilà, chlorophyll photography.
A question suddenly pops: are the colors in images taken into account by the CV?
That’s a good question. CV fails on my UV plant pictures, but it does apparently come up with the correct suggestion for this moth that happened to be around the lichens while I was taking my UV pictures. The pattern on it is very similar to non-UV pictures though so probably not a big difference in this case.
yes. photos showing uv fluorescence have the same chance as other photos of being included in the training set. but even if the cv has never seen a particular organism fluorescing or captured in the dark before, it still should be able to effectively evaluate based on form, patterning, etc.
Wondering if this method can be successful for close relatives, like Brown Elfins.
Here’s a snail I photographed earlier this year. Just your standard garden snail (Cornu aspersum)
Edit- all lighting is from a 365-380nm Glowtech torch with UV pro passthru filter.
That’s very interesting! I wonder why some cowrie shells glow bright red under uv.
I’ve noticed the males of Common Whitetail dragonfly (Plathemis lydia) glow bright red under UV light too.
Anyone knows why?
Observation: https://forum.inaturalist.org/t/uv-fluorescence-in-nature/47310/34
It would be helpful, when feasible, if people could say what uv wavelengths were in play for the photos posted.
I now only have Uv flashlights and one ancient’s UV poster tube light (assume longer wavelengths).
Anyway, it could be helpful to know the lamp characteristics, given how differently stuff reacts to different wavelengths.
Btw- I once caught ringworm when volunteering at a small pet rescue. The lesion was diagnosed as ringworm using a specific wavelength light.but I don’t remember what the doctor said the lamp was.
All my light sources are 365nm, plus additional UV pass/IR block filters stack add to the light sources to eliminate all the visible light. :-)
apparently, there are 2 classes of chemicals that produce UV fluorescence in mammal fur:
the interesting thing is that tryptophan metabolites are found in other organisms, such as ommochromes in the eyes of crustacea / insects (is that why some insect eyes seem to have blue / cyan fluorescence?). meanwhile, porphyrins are components of chlorophyll (is that why chlorophyll fluoresces red?) and other tetrapyrrole molecules like heme, etc., some of which can be found in insects.
if i had to make a wild guess at this point, i would guess that whatever that white pigment is in the abdomen of the whitetail, it’s probably some sort of derivative of porphyrin. but i couldn’t find any scientific literature in my brief web searching.
the whitetails are so common. someone should collect one, analyze its abdomen, and write a paper.
I think the name of lamp for ringworm is called Wood’s lamp.
It’s an UV lamp but not strictly to 365nm.
Thank you very much for the information, TIL.
It’s interesting that you mentioned “tryptophan”…if you look at the UVIVF picture of Common White dragonfly, you’ll see the eyes seem to have blue tint, that’s how I knew dragonfly eyes have natural UV block.
Another interesting UVIVF that I’ve noticed is UVIVF of rat (Genus Rattus).
My dog caught and killed one in my backyard, out of curiosity, I got my UV light and took some UVIVF pictures.
All the pictures are shot with a DSLR camera with additional UV+IR filters to eliminate all the visible light (narrow wavelength ±365 nm).
Here is the observation if you want to see more pictures: https://www.inaturalist.org/observations/104270637
