Efficient 5050 size or less R8000/R9050 LEDs

Flashlight Modding and DIY Parts
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Hello! Looking for efficient ~1000lumen range LEDs to use on 5050 elliptical TIR lenses. Pattern would be anything from 10x45 to 20x60. Currently discounting all inherently efficient <80 CRI LEDs - use case is orienteering/MTB and can’t stand the deficient red-brown colour rendering those give. CCT could be from 4000 to 5000K. Also only using it in continuous operation at 5-10W power range, to get up to 1000lm.

Got it down to 3 (edit: now 6):

  • Samsung LH351D - efficacy seems to be in the ~100lm/W range when driven to 1000lm. Old design, but still haven’t been surpassed? Others barely make it to 80lm/W… Minuses - slightly green tint and requires higher Vf (but lower current and therefore lower thermal dissipation/better battery life)

  • Nichia 519a - seems to be the most popular high eff R9080 around. Newest of the bunch, but efficacy is <80lm/W.

  • Nichia B35AM - better efficiency than the 519a. Requires 6V driver, no thermal pad…

  • Cree XHP50.3 R9080 - similar efficiency as the B35AM? Mostly green tinted in the 4500K bin. Any other drawbacks?

  • Firefly FFL5009 - custom batch for the supplier. Similar to the XHP50.3, but negative DUV. 115lm/W

  • Noctigon NGT50 - similar to the FFL above.

I still can’t believe, that the LH351D is the most efficient one of the bunch? Is there something I’m missing?

edit: XHP50.3 seems to get to 110lm/W, so better then the LH351D and would be the most effient R9050+ LED in the market? The now obsolete XP-L2 seems to be similar efficiency wise… progress?

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LH531D is not R9080, it’s just a ‘basic’ CRI 90.

Are you ok with domed emitters? Because Kaidomain has XHP50.2 80CRI in a pretty high J2 efficacy bin.

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CRI isn’t everything!
The LMP Emitters that Convoy sells and uses are the best example. None of them have good CRI, but all of them (except that 1800K one) have very low DUV and the light looks fantastic.

LHP531 in 6500K and LHP73b in 5000K are my favorites.

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Yep, my favorite emitter right now is the LHP531. :heart_eyes:
(I don’t have a flashlight with the LHP73B yet.) :+1:

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Well… FFL leds, maybe SFT40 3000K. LHP531 have negative R9 :-1: More CRI = more red (R9). More R9 = low Eff.

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NTG50 emitters from Hank are fairly efficient considering they’re effectively R9080.

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They have nice and even spectrum that makes all colors equally pale which looks surprisingly neutral and attractive. But once I shined onto some colors next to less beautifully tinted XHP50.3 R70 I switched back to Cree - XHP50 was the one that made colors pop despite equally low CRI on paper.

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The most efficient high CRI commercially available 5050 emitters are the XHP50.3HI 5000k R9050, NTG50 5000k R9080, Nichia B35AM at low power and the probably most efficient one currently, N5-165HPE++.

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Thanks for all your thoughts!
Reason for the query is not to get pleasantly or even correctly tinted light (it’s a huge bonus!), but to maximize perceived contrast from the forest floor in a short-throw/flood scenario. A little bit better/wider spectrum, than the ‘regular’ pale-looking <70CRI goes a long way (with the efficiency hit of-course)

It seems, besides XHP50.3 CRI80/90, there are couple custom batches from suppliers, thanks for the info!

  • Noctigon NTG50 - quick google suggest a more consistent, prettier tint XHP50.3 9080.

  • Nightwatch N5-160HPE - not a lot of tests come up, but seems to be the higher efficiency, than the others. Could be the current pick, but not easy to source individually. Any more info on these is welcome.

Beaty of the NTG is a high-eff Anduril driver can be purchased together. Or maybe a whole 21700-sized unit? Are any of them swappable with 20-23mm size commonly available stripe TIR lenses?

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Warm White gives you better contrast in the night!

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Luminous seems to take a huuge hit on efficacy going above CRI70. They seem to be the best on spectrum though. Almost no cyan deficiency at all! Tradeoffs…

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They’re custom Nightwatch emitters they use in their flashlights, I don’t think they’re available on their own.

Remember - they’re both 6V LEDs.

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The N5-165HPE++ 4000k inside of the Nightwatch A54 Ultra2 are available to buy separately, just on Taobao lmao.

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Taobao is chinese only, in chinese only, you have to register and login in chinese and so on…

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I used this site to place one order with Taobao.

It’s in English, and it allows one to order from Taobao (in China) to other parts of the world. :grin:

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Not quite–they don’t produce any high CRI emitters in higher CCTs (or low CRI low CCT), so the perceived loss of efficacy is from both (1) higher CRI and (2) lower CCT. Thus, it is impossible to separately quantify the influence of either factor.

A while back they had a batch of SFT40 in 4000K 95CRI, and it had higher efficacy than the 80-ish CRI mix of 3000K 95CRI and 5000K 70CRI. This suggests that their high CRI emitters have very high efficacy for their CCT.

Agree very much with this! At low intensities, warm light appears more natural and contrasty than cool light, at least to the human eye.

I would not bother with R9050 rated LEDs, as R9080 LEDs nowadays can achieve the same efficacy with higher CRI. Go for either 80CRI to capitalize on efficacy, or 95+ CRI for best color rendering. I would go for the latter as the efficacy loss is really not noticeable in practice without a side-by-side comparison.

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And there’s no N5-165HPE there…

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Depends on your tint preference, perhaps a 5700 519a de-domed would be suitable - I’d be considering lux requirements Vs raw lumen output.

CRI doesn’t make up a big part of my decision making process nowadays, CCT and tint are far more important, in my opinion.

Edit: forgot to ask what host you’re using these in?

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OP is not really looking for beautiful tint but increased color rendition and LHP emitters don’t excel in that department.

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AND less glare from snow and fog! Also according to studies oversaturated reds are preferred, even if it degrades the CRI rating. At least under less-than-sunlight intensities. Better to look at the TM-30 data then.
OTOH warm white seems to dull the senses too much. Personally, the sweet-spot seems to be around 4000K. A 3000K bin is too much for the use-case. So is anything above 5000.

Also adding Firefly FFL5009 to the list of efficient 9080. Currently I take the 115lm/W efficacy with ~10W drive level of the new(er) generation LEDs.