LH351D 90CRI Spectrum Tests

Looks like MTN has restocked 4000K +90CRI LH351D’s (bare LED). Anyone know if these are the same as the Digikey ones? P6 flux bin, doesn’t say what CCT bin, I’m thinking it might be the same TP quarter bin.

dont know the answer to your questions, but here are some visuals, for reference
the light in the middle thanks to contactcr

max output reference:
the Cu eTool makes 110 lumens with a 4000k 219c or with a 6000 xp-g2, and it is supposed to make 80 lumens w a 219b 4000k

I was checking to see if there was an obvious difference in “efficiency” as expressed as max lumens on Hi. Albeit the hosts are not identical, they all came suprisingly close to the same outputs, on my light meter, calibrated to an HDS:

73 lm 219b 4.5k Cu Tool w reflector, very pink during the day

72 lm LH351d 5k Aluminum Tool aaa w tir, very neutral during the day, but looks pink compared to optisolis and looks yellow compared to 219b… iow tint is relative

67 lm optisolis 6k JetU w pebble tir, slightly green during the day

Where did you find a tir that fits the tool? I have looked from time to time…

comes on the light from lumintop that way now
https://www.amazon.com/LUMINTOP-Flashlight-Pocket-Sized-Waterproof-Backpacking/dp/B07G98XCG4
they are doing that with the new worm too, now called EDC01

clemence is the master of TiR and cherry picked the one he put on the JetU, I dont know his secrets, maybe ask, or maybe contactcr already can tell you…

My tools and rey lights are all reflector lights…

I’m going to plug my own sale thread cause I’m a rebel.

I’m selling a small batch of the 3500K LEDs from this test along with some other spare LEDs from my parts bin:

Digi-Key “dog fart” arrived. It’s almost identical to the Arrow one tested except for about 100K higher CCT ~4800K instead of ~4700K. Duv is otherwise the same.

for a 2700k option I think the SST-20 might have higher R9 than the 2700k LH351d… not sure… I have not compared their specs…

here is a link to the Warm SST
Luminus SST-20 J3 JA3 Warm White 2700K CRI95 LED Emitter


pic is a link to the warm LH351d source

How does the LH351D 90cri compare to a nichia 319A (80cri) in terms of efficiency and beam pattern? Thinking about swapping to a higher CRI LED in my Quark Mk III…

the higher CRI LED will be less “efficient”, inasmuch as it will produce less total lumens

CRI, and especially CRI R9 go up at least as much as lumens go down

imo, it is worth the trade.

now, depending what CCT you are interested in

there may be reasons to choose 219b over LH351d or SST-20
Im not sure yet, which I would prefer, have not tried the SST for example
I do like the Nichia more than the unsliced LH351d…

for my pink biases the LH351d needs to be sliced,
that also comes with a lumen penalty

If the die of the 319A is close to that of the 219C, the LH351D will be floodier but probably still have more output/be more efficient even binned at 90CRI. The LH351D has a die size right between the XP-L and XM-L2 IIRC.

It’s actually bigger on the LES vs the XP-L die.

I’ve actually become quite fond of the 4000k sst-20 but I believe those would be even less efficient than the LH351D. I have a few lights with that and while the r9 does lack a bit it seems overall quite nice. I’d really like to keep this as bright as possible and the 319 is doing alright for now… just love my high cri options!

I think you might have a 319a D340, if thats true, and you go to a sw45k D220… you would see a 35% lower output… sounds like you might not like that… but

let me play CRI advocate…
say your light makes 340 lumens now
and with a sw45k, lets say it “only” makes 220 lumens

the low CRI is only 54% brighter… that is not really a big visual difference
and you give up all Red rendering… to get those extra 120 lumens… is it worth it?

you know best… :wink:

lucky for you, that version of the quark is not glued… tinker on!

Sorry, that’s what I meant unless XM-L2 LES is same size as XP-L? I only assumed larger due to the pad.

HDS has adopted the LH351d 5000k as its next High CRI offering.

It produces 300 lumens in an HDS
the sw45k produces 200 lumens in an HDS

so the LH351d is 50% brighter than the sw45k
equivalent to one hop on the HDS dial.

the LH351d is a 9050 LED with tint above the BBL
the sw45k is a 9080 (more red), with tint below the BBL

The Samsung LED still has better cri and r9 than the natural light coming in my office today:

Two measurements taken in Texas, today at 2:45PM, overcast day. First is indoors with no artificial light, only ambient light from window - the next measurement is when I step outside.

like of your anDroid ColorMeter app :+1:

good time for a dogfart :person_facepalming:

can you also show the ColorMeter data screen for the LH351d 5000k please?

Here is the Sofirn sourced 2700K LH351D

Very similar to the DigiKey one I tested but with a better price.

1Amp with Frosted TIR:

Would be interesting measure after slicing for know if DUV and CCT decrease at very low current.Cheers