As you ramp up current the tint gets a bit colder and farther bellow the bbl, ie negative Duv, ie rosier. I don’t think it’s cri, these two parameters (color temperature (cct) and rosyness (Duv) are enough to change what you see. Also, obviousy, it gets brighter haha, so harsher for sure!
Just to clarify:
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Normally duv and CRI are independent (ok, not technically true because 100CRI is 0duv by definition), but in this case they are related because of a common underlying cause: an excess of blue emission, which simultaneously drops duv and CRI.
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The harshness I see has nothing to do with brightness, I refer to the spectrum of the light. Reds and pinks in particular become more blue shifted and desaturated, and white colors look off-white.
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The drop in CRI as current increases is a known phenomenon, a recent example is the 719A test. Looking at the 5000K variant, the CRI drops from 92 (68 R9) at 0.3A to 88 (38 R9) at 3A, accompanied by a growing blue spike in the spectrum.
That’s only because 3a very quickly destroys the 719a. It’s not like there’s a universal inverse relationship between current and CRI. If you overdrive and emitter to the point of death that’s something different.
Tint does change with current, that’s definitely a thing, it’s in the datasheet. It’s not always for the worse or enough to change CRI though
I understand what you mean, I meant that partly as a joke, but… only partly. Surely it has at least something to do since they are correlated and it’s hard to take brightness out the equation when comparing from low to high brightness. If I had seem a measured significant blue spike in a 519A test I wouldn’t have said anything. I couldn’t find a high-low comparison of the spectrum test.
For most high CRI emitters, there is a universal inverse relationship between current and CRI at the upper end of permissible drive currents. As current (and thus power density) goes up the phosphor becomes overloaded and no longer converts the same proportion of blue light to white light, and ends up letting through a ton of blue. That always lowers the CRI as blue-pumped LEDs already have a blue spike to begin with.
Here’s another way to think about it: we know that the CRI is ok at low currents and lowers when the emitter is driven near-death. If CRI varies continuously with current (which I think is reasonable), then on average it has to decrease with increasing drive current, that’s essentially the mean value theorem for derivatives.
Hi!
I’m new un the forum and un the flaslight world. I need a lot of help.
I want a S2+, I need it for indoor use only for a hace a compact flashlight always ready. I was reading then I reckon that I need is an orange peel reflector, rubber switch, o-ring in green and clip. But I’m need advice about the led. SST40? 519A? Other?
Other querry: is the tube for the battery important?
And finally: how may modes are more useful?
Thanks!
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For indoor use, the 519A is ideal IMO. I’ve tried all the color temps and like 4500K the most. It’s just a matter of personal preference, though.
You shouldn’t need anything extra for the battery tube unless you want to use a weird battery size like 18350. The S2+ takes the much more common 18650 battery natively.
I always get the 12-group version because there are more options to set it up with. I like group 10 (1% 10% 35% 100%) but you may have different needs.
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If you are mainly using it indoors i definitely recommend the 519A the 4500K is fantastic if you’re not sure if you want Warm(Orangey) or Cold(Blueish) light.
Also if you don’t need the light to throw far, I highly recommend the 45° pebbled TIR for a smooth floody beam.
The 12group driver is a great option because you can configure the modes the way it suits you best.
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Thanks, INeedMoreLumens, you solved muy querrys.
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Thanks, nicodimus22! Great advice, I am going to consider It.
Regards,
Known as “angry blue”. But that’s a much sharper increase than the gradual increase from low, to normal, to reasonable-overdrive. I’m guessing the blue spike really spikes up at that point.
That’s a sharp dropoff beyond a certain point though, you could say the same thing about the low end. CRI is zero when there’s no light.
One cannot quite say the same thing because CRI as a function of power input is not continuous at zero, or at the point of failure. Whenever the LED still lights up continuity is a more or less reasonable assumption.
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I see some lights coming out with the 46800, 46950 and 46110 cells replacing 3-21700 or 4-18650’s. Example Lumintop GT110 SBT90.2 7000lm 2720m Thrower Flashlight – Nealsgadgets and LUMINTOP Mach XHP50.3 26000lm Flood 46950 LED Flashlight – Nealsgadgets any chance of you trying out these cells. 46950 is 32,000 mah and can discharge 1200 watts, 46110 is 38,000 mah. Batteries are made by EVE and CALB.
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See my reply to the Mach thread. I have the Amutorch DM90S with the 46950.
Hello Simon! Do you plan on ever offering the nichia E21A in any of your lights? Or maybe just selling them separately??
B35AM eqauls to 4*E21A,
what about B35AM
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I love my S21B B35AMs. I would also like to see it in S21E and S3+ if TIRs could fit (I think they would, since the XHP50.3 HI + TIRs are available in those).
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I know that, but what I really want is the 2000k cct!
Is there a 2000k B35AM?? I have been wanting one of those forever!
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Does the T4 have thermal regulation?
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