[UVC SAFETY WARNING] Fluorescent Minerals is like a Box of Chocolates

[colinbm]

[UV SAFETY] UV-C Light Is Dangerous

 

NEVER look at a UV-C light.

NEVER let UV-C light hit your skin or eyes directly or by reflection.

UV-C light can cause:

• severe burns of the eyes and the skin, and
• DNA damage from broken chromosomes.

When working with UV-C illumination, you MUST:

• cover up completely, 
• wear head & eye protection, and
• have strong ventilation.

---

 

Fluorescent Minerals is like a Box of Chocolates, 

You never know what you are going to get !

Sodalite is a popular mineral with the Fluorescent Mineral collectors as it displays well under Black Light.
Here is some Sodalite in Eight UV wavelengths from Far UVC 222nm to 365nm & one in Visible light.

Sodalite in Visible Light 400nm - 700nm.

 

Sodalite in Far UVC 222nm Excimer Light, Induced Visible Fluorescence, safer to use. Protect eyes, face & all skin.

 

Sodalite in UVC 255nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed. Protect eyes, face & all skin.

 

Sodalite in UVC 265nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed. Protect eyes, face & all skin.

 

Sodalite in UVC 275nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed. Protect eyes, face & all skin.

 

Sodalite in UVB 295nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed. Protect eyes, face & all skin.

 

Sodalite in UVB 310nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed. Protect eyes, face & all skin.

 

Sodalite in UVA 340nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed.

 

Sodalite in UVA 365nm LED, Induced Visible Fluorescence, knowledge of the safe handling this light is needed.

 

[Stefano]

It's beautiful how it goes from orange to green/blue. The 222 nm image is an outlier, it is very different from the others. Are you sure there aren't leaks?

[ulf]

Some variants of Sodalite also lose their visual blue or purple colour when exposed by bright light.

Those areas often become pale pinkish instead. That is called Tenebrescence.

https://www.naturesrainbows.com/post/2016/01/01/what-is-tenebrescence-all-about-hackmanite

 

I have some from Afghanistan that do that when I illuminate them with my Convoy S2 White torch.

[colinbm]

Thanks Stefano
There could be a leak but I haven't found any graphs 200nm to 1000nm ?
I would like to find a LED between 222nm & 255nm, say 240nm, just to compare & see the transition.
There are two different filters available for these 222nm Excimer lights, one is clear to the eye & is doped to block the rest of the UVC 240-290nm.
The other filter has a silver perhaps dichroic surface & also blocks the rest of the UVC 240-290nm. But neither gives a graph past 300nm.
I prefer the SunTechLed filter with the silver finish....

 

Here is the BBT Best Bright Technology clear filter...
I can't find their graph, but it was similar, but was bright in visible.

 

[colinbm]

That is interesting Ulf
Does the colour come back after the white light is removed ?

[Nate]

Excellent comparisons Colin, quite the difference.

[ulf]

49 minutes ago, colinbm said:

That is interesting Ulf
Does the colour come back after the white light is removed ?

No, it is kind of reset to a bleached state and not until it is illuminated with UV again it is getting darker.

 

Some minerals have a third light emitting property, an afterglow like the one you might have on your wristwatch.

[colinbm]

That is good that the Sodalite is recoverable with UV light.
The after light or luminescence is hard to photograph as it is weaker & fades quickly.

[KaJashey]

These are very good. I've been surprised at how the visible color changes with different UV input.

[otoien]

Very nice comparison. I wonder how a combination of the 222nm and 365 nm frames would look like? The max fluorescence appears to be located at somewhat different locations of the sample at those two extremes.

[colinbm]

@Nate Thank you.
@KaJashey Thank you. Yes it got me sucked in a couple of years ago. I have been building a set-up so I can record it all.

@otoien I am not sure what you mean. Can you do it with these pictures here ?

 

 

[dabateman]

Colin you could load your 222nm image as blue layer, your 265nm shot as green layer and your 365nm image as red layer in Gimp.

That could show an interesting merged image.

 

[colinbm]

5 minutes ago, dabateman said:

Colin you could load your 222nm image as blue layer, your 265nm shot as green layer and your 365nm image as red layer in Gimp.

That could show an interesting merged image.

 

Thanks Dave
I will try it out, but I will need a bit more of a guide please ?
I'll get Gimp loaded.

[dabateman]

Colin read here for Bernard's guide to align the images and overlay the images. Its closer to the bottom of the long post:

https://www.ultravioletphotography.com/content/index.php?/topic/3500-fullfalse-colour-uv-photography/

 

[colinbm]

Thanks Dave
I'll give it my best shot.

[Doug A]

Really enjoy seeing the color changes in different light. 

Thanks for sharing,

Doug A

[otoien]

16 hours ago, colinbm said:

 

@otoien I am not sure what you mean. Can you do it with these pictures here ?

16 hours ago, colinbm said:

 

 

I was thinking along the lines of blending the colors of the existing captures by layering, but may be that is not that good idea - I now notice that the frames may not align well, at least the depth of field appears different in the two 222nm and 365nm frames.

[OlDoinyo]

I assume the orange fluorescence is the familiar S₂^- fluorescence described in this paper. The green, blue, and magenta emissions seen with shorter-wavelength excitation are presumably something else. Another reference suggests the green might be due to manganese, but I am uncertain if the same mineral is being described.

[dabateman]

@colinbm

Well it was a little bit more tricky to merge the images but I did a merge for you incase you were wondering. I first needed to crop them to the exact same size, then do a hugin alignment and then merge the colors in Gimp.

Here they are not well aligned, sorry.

Blue is 222nm, Green is 265nm and Red is 365nm:

 

But I actually like this one better with Blue 365nm, Green 265nm and Red 222nm:

[colinbm]

Thanks for doing this Dave.
I am sorry but I couldn't get my brain around the idea of doing this.

On 10/20/2022 at 12:42 PM, OlDoinyo said:

I assume the orange fluorescence is the familiar S₂^- fluorescence described in this paper. The green, blue, and magenta emissions seen with shorter-wavelength excitation are presumably something else. Another reference suggests the green might be due to manganese, but I am uncertain if the same mineral is being described.

Thank you, I have just seen this & will read it.

[ulf]

I do not think merging makes sense as all the images are wideband VIS.

The source images here already have colours and merging them just increase the confusion for me.

 

Is merging not something you mostly do to combine mainly monochrome narrow-band images to create a new false colour image?

[dabateman]

6 hours ago, ulf said:

I do not think merging makes sense as all the images are wideband VIS.

The source images here already have colours and merging them just increase the confusion for me.

 

Is merging not something you mostly do to combine mainly monochrome narrow-band images to create a new false colour image?

I like the merger as a new artistic image. 

The narrow band images tell you something and that is lost when you merge them. Similarly these tell you something about the visible fluorescence which is lost on merging.

However, thinking about it,  if you look at the merged created yellow, magenta, cyan,  then you do get something about the similar parts that have fluorescence. 

[ulf]

As an artistic image, absolutely.

I was just narrowminded looking at it from a scientific point of view.