Found it. 8bux a pop. Go crazy…
https://www.illumn.com/monthly-specials/nextorch-gt6a-s-6v-xenon-80-lumens-1-x-18650-2-x-cr123a.html
Better yet, running it on a Li cell would be a lower voltage, so while it’d be “redder” than running offa new ’123s, it’ll end up being a long-life bulb, nowhere near being stressed out.
Zero LVP, though, so you could potentially run it down to 0V if left on accidentally, so take that into account, too.
Wellp, you’d have to run a hotwire bulb to supernova to get that… More like a flashbulb.
MAYBE if you find a violet-source “white” LED, you’d get a better spectrum in the blue-green. Otherwise, nope, none of ’em will have it.
That’s why I am going LED.
Clemence recommended the Nichia Optisolis, and I am really considering it. https://www.virence.com/product-page/nf2w757gt-f1
His MCPCB can host 4 emitters close together and they can be controlled independently. https://www.virence.com/product-page/vr16sp4-v2
i agree with this - no LED will really have an even distribution like white light
go with halogen
possibly build a variable power supply to go from warm red to orange to yellow to blinding white
so what if it uses 10x the power per lumen
a couple 18650s should still give you 20 min run time at max white
i would also think you need a UV light with the visible part filtered out
It is OK if I cannot reproduce perfectly a black body emission 
I am not doing any ultra accurate science work, I just want higher-than-average colour rendition when I look at parcels of gemstones anywhere in the world.
As I said, most flashlights used by gemologists of gem merchants are low CRI and not very good quality.
I want to make a small led light (zebralight-sized) I can bring with me on the field, with high runtime, tint and brightness ramping (similar to the Sofirn IF25).
I know it won’t be perfect like a standard illuminant, but it is OK for the work I want to do with this light.
Interesting and unique project you are aiming at. If i understand well you’d want a high CRI pocket size light that you can pull out anywhere to look at a gem with the ability to easily switch brightness, color temp, and have the extra UV capability in one light.
As mentioned before, the UV integration with the other leds might need some thoughts as you probably want a ZWB2 filter that does not work with visible light obviously. Maybe some UV leds don’t need a filter or have their own? That would simplify things a bit.
A rather easy mod to start with would be to do an emitter swap on the Sofirn IF25 to get the right tints and CRI. I did not understand what’s wrong with this light? Too big?
Now, as this is a professional tool… why not get someone to build it for you? There are some very capable members here that would save you the learning curve - time and efforts… for a few gems i guess. 
Salut Patmurris
Yes this is exactly that!
Indeed the UV integration my be difficult but I can drop it if it proves to be too complicated.
Regarding the Sofirn IF25, the emitters are too far apart from each other. It would be much better to have the emitter very close together, that will reduce the size the the cone-shaped head. Please take a look at the second exemple of gem flashlight I linked in the first post. Also I don’t think it can drive the ultra-high CRI emitters I want.
Well I am very interested in doing it myself, that is also one of the major reason I don’t want to buy an existing light for it I am not in a hurry and I quite like the flashlight hobby, the learning curve is not a problem. It is also not a problem if I go through several prototypes until I get it right. Consider this as a project for a year or two.
Right now I am reviewing several options for the emitters, and the Nichia Optisolis + Clemence’s MCPCB look very interesting. 4 emitters, x2 2700k and x2 ~6000k can be run independently on this board if I am not mistaken. The emitters are also very close together as I want it.
There are a few things I need to learn more about, such as drivers and UI coding.
A friend has a Lathe and he could machine the body for me so that is not a problem.
seems to me one of the small double reflector hosts set up with xenon bulb on 1 side and a uv with woods glass on the other would be the best.
with the differences in the blue green cyan range i see leds are going to be inaccurate for that.
a xenon incan is likely the answer.
i say go for it. You have the requirements defined for the features you want and nobody makes one, so why not just roll your own diy light, have fun and learn some stuff along the way? Once you make it there will be plenty of folks drooling for one.
The OP has lathe and mechanical and soldering and electrical skills, just asking for some help with the coding and electronics for driving, etc. No need to argue about why he can’t do it— he wants to be the flashlight king at the gem shows so just give him some help if you can to make it happen.
Geologist here so fairly different skill set and light requirements but I’m interested what the tint ramping requirement is for?
If you would want to drop the tint ramp, I’d go with high CRI emitters in a mixture of CCTs to approximate 5000K
Should give a nicer overall light output than a single emitter.
Others may correct me but I think a driver with PWM would reduce tint shift at different light levels.
@kennybobby Hell yeah that is the spirit!
Hey, geologist as well here 
Why tint ramping? I don’t really need it, but it is cool so I want it!
Suspected as much, perhaps have a separate snazzy tint ramping light for fun and a gemology light at a fixed CCT ?- I would have thought the point of this light would be to act as a “reference light source”, therefore tint ramping would actually hinder accurate observations as you’d rely on the lamp being the same CCT between stones?
Halogen is nice, I’ve a ‘3.7v xenon P60 drop in’ that produces light that none of my LED lights can really match when side by side.
I’ve also used a 219B 4500K light to illuminate hand samples while studying them with a loupe when I was in dense jungle- amazing how little light reaches the rainforest floor!
In gemology we usually inspect gemstones under neutral to cold white light. We also need incandescent light to look for any colour change effect.
My lamp would have both, and I would use the cold white as reference light source for all the stones I look at (right now I use my nitecore MT06MD w/ Nichia 219b 5000k). I won’t necessarily use tint ramping but I still want to have the option.
The light doesn’t need to be 100% black body radiator, that’s why I am going with LEDs.
Gemstones can look very different under many kind of lighting. A stone can look horrible under standard lighting, but look great under non-standard fluorescent lighting. Gemstone also show different colours when you look into it depending on the cut, and the colours can shift depending on the angle you look at the stone. Many have tried to set a standard for gemstone color grading, many have failed and the current system is not very used anyway because of the reasons above. It is more like a guideline to set up price.
In the end, gemstone colour grading is relatively subjective, it is more like an art unless you are a gemstone lab with high end equipment to follow the standard.
Now for xenon I would use this kind of lighting in my office desk for example, but I’d rather have a small LED light on me when I travel.
And as I said I want to make it myself because it is fun! (all my gemmo friends will be jealous )
Where were you in the jungle? South America? South East Asia? Looking for ore deposits?
Great info—thanks for sharing this, Lightbringer.
There are a few CRI98 LEDs
One option is the Nichia E17a in CRI95,
they are small enough so you can mix like 4 of them onto one MCPCB with up to 4 different colors, may even include colored ones (RGB)
he has tested those quite intense
and also special MCPCBs
for UV, I would go with a Nichia LED and ZWB2 filter
Hey Lexel, thanks, this is exactly what I need!
thumbs up on working with Clemence and Lexel
very interesting project
I wish you good progress
Thanks Jon
Right now I am very busy working on my thesis, but once I submit I will have more time in my hands to get this project started.
Hmm, the BLF Gemfire…
Maybe this could be of use, it has the UV 365nm you look for, and you could get someone on here to swap the other led’s if you can’t do it yourself (if you wanted that is)
