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Spectrum of my safety glasses

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#1 dabateman

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Posted 28 July 2020 - 14:24

Well my Jaz spectrometer might not be sensitive enough to detect the 380nm leak we see in the orange UVex glasses.

I have a DT1000 light source and just collected spectra of my clear, amber and orange glasses.

Clear goggles:
Attached Image: Clear.jpg

Amber UVex ultra-spec 2000 S0290X:
Attached Image: Amber.jpg

Orange UVex Ultra-spec 2000 S0360X:
Attached Image: Orange.jpg

I see a 380nm leak in the Orange glasses when tested on camera with filter sets.
But the Orange block more 255nm light as I see slightly more go through the Amber than the Orange with UVc filter testes on camera.

The Amber glasses were ordered January 2019 and the Orange were ordered June 2018 both from Amazon.

Edited by dabateman, 28 July 2020 - 14:25.


#2 Cadmium

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Posted 29 July 2020 - 00:44

David, Is your Jaz spectrometer a new acquisition?

#3 Bill De Jager

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Posted 29 July 2020 - 03:18

One question I've long had is how far sub-200nm UV will travel through air. Of course that will depend on its intensity, but I've really had no idea whether a reasonable intensity of such light (say 100 lumens) might travel mm, meters, or hundreds of meters before being reduced to insignificance through absorption. I see that your light source is able to travel at least a very short distance through air.

#4 colinbm

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Posted 29 July 2020 - 03:29

Yes Bill that is a danger, the safety goggles will pass UV vacuum & there is the added danger of ozone being produced....

#5 dabateman

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Posted 29 July 2020 - 05:02

View PostCadmium, on 29 July 2020 - 00:44, said:

David, Is your Jaz spectrometer a new acquisition?

Newish, bought in April, got sent back and fixed in May for an excellent price. The seller was very good. It is capable of seeing the 185nm line in a Mercury Ozone bulb. The IR module is a little tricky though so can see up to 1100nm or little over. But you have to work hard for it. The IR module has a long pass blocking filter on around 500nm.
Still trying to work it out for its original purchased purpose. Which is completely unrelated to photograph, filter and led light scanning, which it seems to work for.

#6 dabateman

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Posted 29 July 2020 - 05:14

View PostBill De Jager, on 29 July 2020 - 03:18, said:

One question I've long had is how far sub-200nm UV will travel through air. Of course that will depend on its intensity, but I've really had no idea whether a reasonable intensity of such light (say 100 lumens) might travel mm, meters, or hundreds of meters before being reduced to insignificance through absorption. I see that your light source is able to travel at least a very short distance through air.

That would need a more controlled environment than I have to provide a useful value to. I can say with my many more experiments with 185nm light than I should have conducted, that humidity plays a major role. Moisture in the air definitely effects the distance reflective 185nm mercury lines can travel. A variable that is hard to control, but I do see correlation with what my dehumidifier can read out and the absence of the line.

For these safety glasses measurements, I projected my DT1000 light through a culminating lens and had about a 6 inch air gap. Then had a focusing lens on the other side to collect the light back into an other fiber optic cable to bring it to the spectrometer.

I wouldn't trust any signal below 250nm, as that for sure would be noise in this test. I just was more focused on the around 400nm cut off of the glasses. Which can easily be projected at further distances with my light.

#7 Bill De Jager

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Posted 30 July 2020 - 04:34

Thanks, David.

#8 colinbm

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Posted 30 July 2020 - 05:30

Dave, this DT1000 light, is that bright enough to photograph with or just enough to go down a fibre for a spectrum ?

#9 dabateman

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Posted 30 July 2020 - 05:41

View Postcolinbm, on 30 July 2020 - 05:30, said:

Dave, this DT1000 light, is that bright enough to photograph with or just enough to go down a fibre for a spectrum ?

Its mostly a point light source. I can illuminate a sample on a microscope. I guess I could light paint a larger object or expand the light with lenses.
What did you have in mind?

#10 colinbm

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Posted 30 July 2020 - 05:43

I was just wondering if it was suitable as a light source for photography.