Graeme said:
Arpit <[email hidden]> wrote in
news:[email hidden]:
Quoted message said:luoro works by converting ultra violet light into visible light
(fluorescing) its MUCH more visible in twilight and when its cloudy,
compared to white stuff, because the ratio of uv to visible light is
much higher then.
It sounds like much of the stuff this thread has mentioned isn't really
fluoro, but "day-glow" i.e. eye pokingly bright colours. Apparently it is
incredibly difficult (impossible?) to get true fluoro into the fibres they
make the cloth from and even if they could the effective life span is
pretty short.
Graeme, I respectfully differ on both points you make.
* As far as I know, "day-glow", aka "dae-glo" (or something similar)
coloured pigments are the same as what are now called fluoro colours.
They were called "day-glow" because, as arpit wrote, the pigments picked
up UV but reflected it in the visible spectrum, hence "glowed" in
"daylight".
Bright pigment colour dyed clothes, like my dear old bright red wool
jumper that has kept me so on-bike warm for so many years (mostly under
fluoro gear, tho) are very visible compared to more subdued pigment
colour dyed clothes like your Japara or black Levis, but they are simply
not as visible as fluoro colours.
Consider a rainbow tie-dyed t-shirt v your standard fluoro yellow Netti
shower-resistent zip-up top. The Grateful Dead fan's t-shirt's
pigment's yellow (whew! s'o man'y a'postrophe's!) would reflect back the
(less whatever amount that isn't reflected but absorbed, and changed
from light energy to heat, or (umm.. guessing here) entropy in the form
of fading or denaturing the pigment and/or fabric in technical formulas
that we just ain't concerned with here) R:254, G:254, B:0 and similar
wavelengths of the sunlight that falls on it. The Netti top, however,
reflects back the R:254, G:254, B:0 spectrum light and similar
wavelengths, PLUS the UV converted to visible light from similar
wavelengths.
What I mean is, a garment dyed with bright yellow pigments is not as
visible as a garment dyed with bright yellow pigments that also take UV
light and reflect them yellow wavelength light.
* I forgot to take my yellow sunnies to lawlib today... now, how the
feck does that work? How does blocking out a whole lot of the spectrum
with yellow lenses make things more visible at night or in low light
conditions? OK, so yellow lenses make things look more sunny (even tho
fine day daylight peaks on the blue end of the spectrum) on rainy days,
but at night, too? What is the deal with that?
Ahem.
I forgot to take my yellow sunnies to lawlib today, and (as I would
have, anyway) took the long way back home in growing twilight. As the
sun set, I noticed that my:
- 8 years old fluoro yellow socks;
- 5 years old Netti rain-jacket; and,
- 11 years old, fabric-wise, and home-made, fluoro thermafleece jacket
were fluorescing their little hearts, if garments have hearts, out.
Most of above-mentioned garments are very faded. But they still seemed
to catch the sunset UV, and do their dayglo thing.
Moreover, whenever I'm wearing my bike gear and take a / in inner city
public toilets lit with UV lights (so that... well, y'all know why there
lit like that), my ancient kit nevertheless lights up like a Christmas
Tree.
Quoted message said:
"Paul_MCMLIX" <[email hidden]> wrote in message
news:[email hidden]...
Quoted message said:I stand corrected...whatever the stuff is called, I just meant 'really
bright stick-out-like-dogbally stuff' that decreases the chance of you
getting skittled by a semi...
I think that
Quoted message said:
But insects are attracted to bright things...
hippy
;-)
And to hippy:
Yeep!
Do you have scary moments when you walk your bike out the door to ride
to work, and all the bees in the front garden decide that you are far
more interesting than the petals they bin bzzzing at?
Apparently, many flowers have UV-light-only pigmentation, because bees'
vision is in a shifted spectrum to us vertebrates. Or something.
[censored] (to a.b all)
p
