What is UV light suppose to show/look like?

[ryansoh3]

No problem, have fun with the UV light and the goggles.

Have you owned a 445nm laser? Can you estimate the wavelength of the UV light? I don’t think I can trust the 375nm rating.

[ohaya]

@ryansoh3

No problem, have fun with the UV light and the goggles.

Have you owned a 445nm laser? Can you estimate the wavelength of the UV light? I don’t think I can trust the 375nm rating.

Hi,

No, I have owned any lasers. I’m not sure I trust the 375nm spec either… that was the 1st thing I was wondering about when I couldn’t “see” and started this thread.

[cat_eyes_evil_twin]

@hank

Also you can add filters that pass the UV but block the visible light (or most of it).
Ask around locally for a photography or theatrical supplier who carries Rosco filters, and who can give you their “swatch book” free as they describe here: SWATCHBOOK REQUESTS | Rosco

I, uh, forget which ones I used — each sample has its transmission curve attached. Page through, look for a curve high up at the violet end and very low in the midrange. I stacked a couple and got a result that’s barely visible purple but makes things fluoresce nicely so it’s transmitting much of the UV.

hey there are six swatchbooks to choose from…
does anyone know which one has the UV filters ???
thanks

[hank]

Remember, a “uv filter” is a filter that filters out ultraviolet. Lots of those around.

What you want is a material that transmits below say 500nm and filters above that.
The Rosco pages have transmission curves available for each of their materials. If you go to the local source as they tell you to do, you can flip through them and look. Or you can look on the Rosco website for the transmission curves. I’m sure what I used was one of the deep blue colors, with a curve that showed a lot of transmission below 500nm.

If I ever find the scraps or notes I will come back and post them — but I’m sure I did not search exhaustively through everything available, I just skimmed til I found some that looked likely, then went to the local theatrical supplier (phoned ahead, asked if they had swatch books to give away free, they said sure, got a ton of’em, come on by — for them it’s good exposure to have people show up).

[hank]

ok, I used a ‘Cerulean Blue’
http://www.rosco.com/images/filters/roscolux/375.jpg

but it looks to me like ‘Winkler Blue’ would do as well:
http://www.rosco.com/images/filters/roscolux/368.jpg

Note those images have the transmission curve and tell you the name of the swatchbook they’re in.

But also note there’s a new swatchbook every year or so and they do change some of the numbers and names from time to time.

One of these is worth getting: http://publiclab.org/wiki/spectrometer

Remember if you have a dropin that’s putting out a lot of blue light that interferes, that’s what you want to remove. So you want the transmission curve high down around the frequency of the UV — 30 to 50 percent is pretty good — and as low as possible once you get much above that frequency (400 and higher).

Putting the yellow/orange eye protectors on may actually give you better results, since that blocks the blue end effectively also. Some things (paper and cotton fabric and of course “cool” phosphors generally) fluoresce bright blue, I don’t know how those look through the orange goggles.

[cat_eyes_evil_twin]

hey thanks for taking the time to help.
.
i need to clean up cat spray from a territorial war.
which wavelength of uv is best for biological.??
this question was asked in OP and never answered.

and is there a light with the good wavelength already
available for sale ??

i would like to mention that defiant at home depot
has a UV light under $10.

it puts out a lot of purple light so i need to find my
old yellow shooting glasses…

---

i am becoming concerned that cree leds put out a lot
of UV light that could be damaging my eyes…

i may start wearing protection at night…

[hank]

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