Nichia E17A/E21A Skilhunt H04RC Group Buy

I do not see how this luxmeter would change things, it is yet another cheap luxmeter that for sure will have optical filter errors. A good luxmeter filter that precisely corrects the sensor for the Vlambda curve is still very expensive (as in hundreds of dollars for the filter alone), and none of my tests sofar have proven otherwise. So there is no way around that, and errors of 10% upwards will remain. I have not tested this specific luxmeter but I have no illusions.

In your tests UT383 did way better than other cheap meters. If UT383S performs as well, it’s probably significantly better in the cool region HS1010A that TA uses.

If you look into the table I made of how the different meters measured a number of different flashlights, you will see that while it performs better than some others, the U383 depending on light source, measured from 5% too low to 15% too low so a 10% variation on top of the calibration error, which does not make it a great luxmeter, just better than the worst ones. That is quite a range of error to consider. There seems to be a performance in between, the one Extech meter that I tested differed only a few percent from the reference luxmeter, which also shows in the wavelength response.

Unfortunately no, this is not for you. This H04RC steps down in 2 minutes to ~50% max output. Less than 400lm continuous with R9080. You better look for bigger light, not a headlamp.

[Clemence]

Nichia Esttool simulation (proofed to be very accurate)

4x E21A sm355 D220 R9080 (Tj 85°C, 4P)

Mode 7 (800mA)

- 259,9 lm

- 2,665 V

- 122 lm/watt

  • 2,132 watt

Mode 8 (2500mA)

- 744,5 lm

- 2,8575 V

- 104 lm/watt

  • 7,144 watt
    —————————————-

4x E17A sm355 B11 R9080 (Tj 85°C, 4P)

Mode 7 (800mA)

- 248,6 lm

- 2,7825 V

- 112 lm/watt

  • 2,226 watt

Mode 8 (2500mA)

- 665,8 lm

- 3,01V

- 88 lm/watt

  • 7,525 watt

With E17A, optical efficiency would be higher but both regulation and heat generation are worse.
[Clemence]

But TA calibrates with reference lights which should cancel this error.
And I think $370 for Extech is way too high for an average enthusiast. At least I keep it out of my scope.

It’s hard to find a high CRI headlamp.

My 400-500lms figure is pretty rough anyway. When the H04RC steps down to 50% max output, what is it’s rough output? Just under 400lm?

Looks to be about 250 lumen

Vary depends on the LED CCT. For 3500K its 225lm. 6500K would be about 250lm

[Clemence]

I think we need to keep in mind that this would not be just an standard 90 CRI headlamp. The LED’s provided for this Group Buy are 9080 LED’s, with a very high R9 colour rendering.

From my experience, your pupils will dilate to adjust to the light provided by a headlamp/flashlight. A small compromise in brightness can easily be adjusted for with your eyes and brain, but not so for colours. Having the super high 9080 LED’s bring out colours that you would otherwise not see as well with a lower CRI option, regardless of intensity or lumen output.

No it does not, spectral errors are not solved by calibration, please read my luxmeter threads for an explanation.

True! I use 4 different calibrated lights from Maukka: 6600K R7O, 5000K R9050, 6500K R9585, and 2700 R9580. They all have different calibration values. I use value closer to the light tested

[Clemence]

I understand the spectral errors but misunderstood your previous post.

UT383 is the only cheap meter that you tested which doesn’t significantly overread the blue peak of cool low-CRI lights.
It loses at the far red. And the sensitivity peak is shifted. I don’t claim it’s great but to me it looks significantly better than anything up to several times its price.

@Clemence: that is a practical workaround to compensate for spectral errors, while your Tasi meter already is relatively good.

How about getting back on topic: the Nichia E17A/E21A Skilhunt H04RC Group Buy ?

Hi Clemence do we need to pay first before we received a confirmation of order.....

Thank you

Just put your comment on the Gsheet and proceed with payment.

Thanks,
Clemence

As an owner of so many Virence modded Tiara Pros with the same emitter, even the 200+ lumen mode is VERY bright. It’s much brighter than I imagine at that lumen level and I’m a fan of lumen monsters. You can see everything very clearly. Probably the ultra HI cri helps. Most of the time I use the sub 10 lumen modes as that is already real bright at night when my eyes are adjusted and even at that lumen level you can make out all the details and colors. For anyone who is hesitating to buy this because of the low lumen rating, trust me you will not be disappointed and you will be using it everyday, likely on the very low levels.

Very professional and informative measurements SKV89 :+1:

Nice warm and rosy. Do you know whether a 2x2000K + 2x3000K mix will be even more rosy?

And do you have measured a 2x2000K + 2x4000K mix?

I’m interested in this group buy, just checking that the buy occurs after 200 orders? Only asking because there are currently 100 rows in the google doc.

If we can hit 200pcs then we can request Skilhunt to make us custom mode/output (no timed step down). Otherwise, we will order any quantity but, with normal mode/output like OEM.

[Clemence]