Why using color LED when you can use color glass filter ?

LED Flashlights – General Info
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For evenings, I use lights that don’t emit in the 400-550nm range (which affects the sleep cycle, particularly for babies and older people): http://ehp.niehs.nih.gov/119-a472/

So we use mostly amber LEDs (widely available as “turtle-safe” lighting, you know how to look this stuff up (grin)).

I also use color filter gels over ordinary light sources.

LEDMuseum is a wonderful resource (it’s one quirky guy on disability so contribute something if you find it useful; he’s been a reliable source on the Internet since before it got the wwws.

http://www.ledmuseum.candlepower.us/eighth/l15way25.gif (amber)
http://ledmuseum.candlepower.us/twenty1/sst-90.gif (emission spectrum for a “white” LED, mostly blue)

Remember “white” LEDs are, like “white” fluorescents, actually a blue-range emitter, under a fluorescent material.
That absorbs the high energy blue photons and emits somewhat lower energy photons.

The emission spectrum isn’t the same as the color temperature — a “warm white” LED has somewhat more emission at the warm end but still has a lot in the blue. The very newest warm white emitters are supposed to be using a green emission to drive the phosphor, and so be safer when used in museums on old paintings for example where the blue light degrades the material over time. NOVA | Saving the National Treasures | Fading Away | PBS

Here’s a white LED with a flaw in that fluorescent layer — see the blue-violet streak?
http://www.flickr.com/photos/wossname/3201800207/

here you can see the flaw in the phosphor:
Imgur

So take that “white” emitter and overlay a filter gel of your choice

Click the little icon next to a filter, to see how much of each wavelength is transmitted by the filter, e.g.

For anything in the green-to-red range, filtering out the huge blue part of the emitted spectrum wastes all that energy.

Aside to all, I’m always interested in ways to change LED lights to amber emitters (remembering they use lower voltage than the “white” emitters). One way is to add a resistor but that wastes energy. Another way is to have a driver that measures the current flow through the LED and adjusts it — but it’s hard to find them documented. Pointers always welcome)

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I was using CREE numbers. We have little info about lights, almost everything is based upon manufacturers data.

I used light with my anaglyph 3D glasses (red&cyan) and the results is not that bad that why I ask about color filter, loosing maybe 80% of light and the glass get hot.

All that theory is good but have you compared color LED and a XML light using color glass side by side ?

What do you thing of this P60 drop-in ? Claimed 250 lumens. So under 100 lumens in reality I guess.

Thanks ! This must be awesome to use !

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Then you should go that route, I wouldn’t go with “spiderfire” diffusers.

You may want to get a diffuser to make the beam floody, as the beam pattern off an RGBW quad die emitter will appear off centre in the individual colours

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Match and a handful of other BLF and CPF members have actual calibrated light spheres to read Lumens OutTheFront readings.

As for blue emitters, with out a tailcap amperage reading I don’t know how bright that blue dropin will be.

I really like red emitters, I don’t use blue LEDs as the light is hard on my eyes and gives me headaches almost as quickly as uv light dropins. (I have two uv dropins and love em)

The blue will look noticeably brighter than the red at the same drive current as there’s less phosphor infront of the die to get the desired colour

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It’s all been covered already, but I would point out that the Sunwayman C21C uses a red XP-E (gen1) P2 rather than an XP-E2. Not that that makes any real difference functionally.

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So it does, dang so I still don’t own a red xpe2. Thanks for clarifying RedForestUK

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I own a Nailbender SST-90R Dropin!

If you are searching for a red light, i would prefer one of these Dropins.

These LEDs are the most powerfull colored ones for flashlights.

http://www.luminus.com/products/SST-90C.html

The amount of red light (ca. 360 lumens @3,04A on Turbo) is not reachable with a red glass lens in Front of a XM-L2.

The steps should be around 25 - 70 - 200 - 360 lumens.

SKYRAY King on High ca 2000 lumens.

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XPE2 is only available from mouser etc., so rather expensive. But they are not THAT much better than the old XPE.

SST90 in red is cool.. but really expensive. :D

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To my knowledge no one has built a farther throwing light with a red emitter than this.

I have built hundreds of lights with red emitters and have done all kinds of tests with red lenses over white lights.

Red lenses over white lights kill 60-75% of the throw.period.real world testing not just reading data sheets.

Kevin

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amber thrower

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a plus for glass:

Take for example the Red colors if your Russian the “beautiful colors” (you would think the “Reds” would call Red, Red. But they dont.) :~

If using a glass lens (specfically photo lenses) we have the options of choosing/changing from 590/630/660/720/850/950nm+ nanometer lens ranges, you just cant do that with a emitter.

I really like the c21c and somthing I noticed is that by using both a 635 emitter and a red (unknown but I assume 590nm) lens they have eliminated that darn orange hot spot.

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Note the log scale on this image — “halfway up” the Y axis is only ten percent of the output.
Still useful once you note exactly how the scale works, to see how many photons of each wavelength are being transmitted (or filtered out)

This whole site is a thorough and exhaustive discussion of wavelengths from the point of view of darkroom illumination.

For instance (as Ronin42 notes) a glass darkroom filter allows a very narrow band, while a led allows a relatively wider band of wavelengths.

http://motion.kodak.com/motion/Support/Technical_Information/Processing_Information/Shedding_New_Light_on_Darkroom_Illumination/page33.htm

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We can and plenty of hunters use them... Candela loss will happen but if that meets our wanted range requirements (for most hunters/photo enthusiasts that is under 100m) with filter changing we can have all in one set and it should not be bad at all.

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if you us a color led with a filter i think its better .
i have one 503b red xpg with before the atmoffere lens a red filter.
you lose not realy brightness but the flashlight are more tempered.

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An excellent chart from hanks found site

http://motion.kodak.com/motion/Support/Technical_Information/Processing_Information/Shedding_New_Light_on_Darkroom_Illumination/page08.htm

“This slide shows how both rod and cone photoreceptors in the eye take time to dark adapt, but the rod vision is ultimately about 1000 times more sensitive at very low light levels.”

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try it first, than tell us how it went, especially with red filter

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I have red/green/blue/yellow/frosted filters. Red is really useful for not breaking your night vision at night,blue look close to UV and highlight neon colors,green is like red but you see better,frosted give flood which is useful for close work and yellow is useless with ugly tint. Filter work better with high CRI value.

I don’t have any color LED so I can’t compare but filters are enough for casual use.

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I use red LED’s almost exclusively hunting hogs at night. I can tell you the XP-E2 on a noctigon are better than the XP-E and the XR-E. I typically push mine a little harder than 1.4A and usually add another 4135 to the driver. From experience, the red filters suck. The light is much more dim and is basically I unusable at any distance.

How much are the red XP-E2’s in Europe? I keep hearing how expensive they are. Just curious as I am about to send some to a member over there that he had me order.

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try leds, you will see the difference. filters with bulbs perform good and do offer flexabuility (1 light, many colors), but with leds, you loose performance. they work but not as good as they would with bulbs, and not as well as color leds. we can write pages of text but you need to try one to see the differnce.

filters on leds remind me of cassete tape adapters, you can plug cd player in there and it would work with your cassete deck, but not as good as if you used cd player in a first place.

not to mention nowadays you need just 1 led like mce, or xml colors and have 4 colors rgbw, or triple or quad star with 3-4 color leds. and with rgb controller you can make up pretty much almost any color, and shade you want.

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You can compare the spectra — the vertical axis is, roughly, how many photons are getting through. The horizontal axis is wavelength.