Standard conflicting with Warm LED outputs?

snala

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A question around using both types of emitters at once.

When you bike at night using a high output LED and a normal halogen the LED and halogen seem to conflict so you don't really appear to have two sources of light as they tend to self cancel. I guess it's something to do with the blue in the LED and red in the halogen?
Has anybody tried using a standard white LED and a warm one at once as two sources to have more output?

I want to buy two different torches for varying usages so want to know if I use them in conjunction for mountain biking at night, will they compliment each other?
 
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Saint_Dogbert

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Yes, combining different color temp LED's will result in (somewhat) better color rendition (CRI). That's because the warmer LEDs put out more light towards the red end of the spectrum, the cooler ones more light in the blue end (both still have a pretty large spike between 400 and 500nm). Combining them neutralizes the color temp difference, so that there is a more equal amount of output from either end of the spectrum, resulting in better CRI and of course more output.
 
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tnforever

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I can also confirm since I ride with a warm tank007 and a Fenix L2D, the color rendition is fantastic in my book, especially compared to each light individually.

The tank007 by itself is rather time and makes everything very orange/brown, and the L2D, even on turbo, doesn't look too bright, and makes everything look blue. Combined, I find the light to be quite natural, and turning off either makes me realize immediately why I did that in the first place.

My experience comes from road riding and bike path (paved paths dedicated to bikes and away from roads), as I don't do mountain biking, but i do illuminate some trees and dirt to the side of the path and find it very nice.
 

blasterman

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If you look at spectral graphs you'll see cool white LEDs are very weak in orange-red. Warm white LEDs however have a more pronounced orange-red hump while blue-cyan is subdued. So, if you combine the two, you get better color over-lap. Total CRI is the same as the warmer LED, but is not higher than the two combined because the phosphor mix is the same. To increase CRI you'd have to add an entirely different type of emitter, such as Cree is doing with the commercial fixtures.

For light sources at night I agree that combining the two tints works better than a solo. You get the broad depth and perception that warm light yields with the raw intensity and detail of the colder emitter.
 

mr.snakeman

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This is my experience with my EZ AA and LX2XT lights that I have in both tints, the cold is too cold and the warm is too warm but when they are placed over one another then the tint is just about perfect. I just wish I knew what the corresponding bin and group code for the new tint would be. I´d definately buy a light using this tint! If anyone else has both tints of the aformentioned lights, try the mixing of the two and give the rest of us your comments, please.
 

Saint_Dogbert

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This is my experience with my EZ AA and LX2XT lights that I have in both tints, the cold is too cold and the warm is too warm but when they are placed over one another then the tint is just about perfect. I just wish I knew what the corresponding bin and group code for the new tint would be. I´d definately buy a light using this tint! If anyone else has both tints of the aformentioned lights, try the mixing of the two and give the rest of us your comments, please.

Well, unfortunately they don't make an LED like that right now...when you overlay the beams you are getting a greater spectral power distribution, ie more of the whole range of visible light is being emitted by the combined lights. There isn't currently an LED with a single die that does this - I think there might be some with multiple dies that have like yellow and red LEDs in addition to white and achieve an even superior effect.
 

tnforever

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I'm just waiting for Cree or SSC to make a multi-die LED with two dies of each (warm and cool) in a diagonal pattern, I would think and hope the result'd be pretty awesome.
 

snala

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Say something like the Eagletac M2XC4 with the 3 focused Q5's in different bins would be interesting to see as beam shots then?
 
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Saint_Dogbert

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Say something like the Eagletac M2XC4 with the 3 focused Q5's in different bins would be interesting to see as beam shots then?

I'm just waiting for Cree or SSC to make a multi-die LED with two dies of each (warm and cool) in a diagonal pattern, I would think and hope the result'd be pretty awesome.

Both of those would be frikkin' sweet. However, you'd end up not with all Q5s, because the neutral and warm white LEDs don't come in Q5 flux bins yet. I bet it's possible to mod an Eagletac M2XC4 with a cool-, neutral- and warm-white tinted LEDs without too much trouble - maybe someone's already done it?
 
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