Blacklight or UV

[musht]

It would be interesting (if a little difficult/impractical, perhaps) to do a spectral analysis of the old tubes.

 

https://en.wikipedia.org/wiki/Blacklight#/media/File:Fluorescent_Black-Light_spectrum_with_peaks_labelled.gif

 

370 peak

 

Wood`s glass is named after Professor Robert W Wood, ` Modern Wizard of the laboratory`

 

http://medicalphotography.com.au/Article_04/06.html

[adam2]

It would be interesting (if a little difficult/impractical, perhaps) to do a spectral analysis of the old tubes.

 

No need ! at least one report includes a close up picture of one of the lamps, including a suppliers part number, the spectral analysis should therefore be readily available.

 

 

 

 

 

[alistermorton]

I meant analysis of sleah's actual tubes that he still has, not the ones in the report or Wood's glass tubes in general.

 

Hence "the old tubes".

[adam2]

I meant analysis of sleah's actual tubes that he still has, not the ones in the report or Wood's glass tubes in general.

 

Hence "the old tubes".

 

Sorry to have misunderstood your post, I presumed that by "old tubes" that you meant the ones removed from the venue after the incident.

[sleah]

I meant analysis of sleah's actual tubes that he still has, not the ones in the report or Wood's glass tubes in general.

 

Hence "the old tubes".

 

AFAIK they were just the thicker type tube. I think the older ones were something like T12 (1.5inch) and the newer T8 (1inch). I assumed it was just power output that was different?? :huh:

[bigclive]

I bet the company that did the lighting is not thrilled that someone got a close up picture of one of the tubes. Otherwise the evidence could all have been removed.

 

That's the curse of living in the smartphone era. If you have an incident it will immediately be recorded and shared.

[alistermorton]

I meant analysis of sleah's actual tubes that he still has, not the ones in the report or Wood's glass tubes in general.

 

Hence "the old tubes".

 

Sorry to have misunderstood your post, I presumed that by "old tubes" that you meant the ones removed from the venue after the incident.

 

NP

 

I meant analysis of sleah's actual tubes that he still has, not the ones in the report or Wood's glass tubes in general.

 

Hence "the old tubes".

 

AFAIK they were just the thicker type tube. I think the older ones were something like T12 (1.5inch) and the newer T8 (1inch). I assumed it was just power output that was different?? :huh:

 

That's why I thought it would be interesting to actually measure the old tubes. We were all sure they were fine way back when, but really, were they?

 

Not pointing any fingers, just a bit interested. When I was a nipper, my Dad and I fitted out the youth club at the school he taught at with sequenced lights and a UV source. It's sort of interesting all these years later to wonder if ,in our enthusiastic naivety, we were doing anything we shouldn't have.

[musht]

 

That's why I thought it would be interesting to actually measure the old tubes. We were all sure they were fine way back when, but really, were they?

 

 

Fairly sure BLB T12s don`t go any further down the spectrum than their T8 or T5 successors, largely to do with lamp makers wanting more money for lower wavelength tubes.

 

Some fluorescent minerals only fluoresce at lower wavelenghts, interesting for rock collectors and security markings.

 

Invisble red , 370 sensitive, red fluro dye is difficult and expensive to find , its used as a security marker on $100 bill.

 

UV output not being visible is usually quoted in milliWatts, lumens , lux etc only apply to visble light.

 

LEDs should be treated with respect, lower wavelength ones especially, don`t stare into the pretty blue lites at short range, lacking the IR heat component of a welding spark but power density is getting there.

 

Lots of things block UV, most plastics, most types of glass, problem run into ever trying to make an enclosure.

 

Largest source of dangerous UV is the Sun...

[cedd]

Just to say that Clive has been true to his word and has produced this great video;

[bigclive]

And at the same time this video popped up catching a little technical problem with a parade float where a UV effect caused problems resulting in some arc-eye and skin burns for the performers.

 

The Daily-Fail strangely enough managed to get all their facts completely wrong. (how surprising)

 

Daily mail's usual low-fact fodder for senile old ratbags.

 

But you can see in this video exactly what went wrong. So let's see how many of you can work out what happened.

 

[timsabre]

Was it the old classic of the exploding uv cannon bulb? Had a few of them on wet gigs where someone decided to use an indoor fixture outside.

[niclights]

Or the performer just kicked it breaking the envelope? It looks like the lamp is completely unprotected.

[bigclive]

Was it the old classic of the exploding uv cannon bulb? Had a few of them on wet gigs where someone decided to use an indoor fixture outside.

 

I should have banned the veterans from the competition, since it was obvious they would instantly know what had happened.

 

It does indeed look like open 400W UV lamps that have exploded when the rain hit them. The trouble is that it's actually really hard finding a suitable protected fixture that can take a 400W mercury lamp that isn't huge and ugly.

 

The 400W lamps are a pretty abysmal UV lightsource anyway. They work by filtering the desired notch out of the mercury vapour emission, whereas the fluorescent tubes use phosphor to create output in the UVA band much more efficiently.

[DrV]

Thanks for the video Clive. The subtitler adds an extra layer of entertainment! What would my geriatric EPROM eraser have in it? I'm guessing it is the really short wavelength. It has interlocks to stop it running with the drawer open and the anodising inside is very faded so it must be a bit nasty.

Dave

[bigclive]

The EEPROM erasers use UVC.