Graeme wrote:
>
> Arpit <
[email protected]> wrote in
news:[email protected]:
>
> > 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.
>
> "Paul_MCMLIX" <
[email protected]> wrote in message
>
news:[email protected]...
> > 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
>
> 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.
p