Since I only use the light for low - medium levels, would it be best to get the 8A driver instead of the FET 12 since I won’t utilize the boost driver?
Will the 12A driver still be ok to use for low - medium levels or it wouldn’t be optimized as the 8A?
I am absolutely/unequivocally :innocent: no expert when it comes to drivers (whether buck, boost, linear, direct drive), just want to report my experience with the 8A Buck driver, and even that is seat of the pants type report: it gets hotter than other lights (measured with IR gun it was 59 C, versus my other lights’ 45 C or less), but it stays bright longer with les step-downs than for example same 219b 4500k LED in Emisar D4V2 with max thermal limit reset to 55 C. Basically I like/love the S21D with 8A Buck driver and have no problem with it.
From what I could read, FET driver is not as efficient (more heat) and use PWM to regulate output. Neither characteristic would be considered advantageous. Any expert please correct me or expand discussion as needed.
It puzzles me that as best I could understand Simon, the 8A Buck driver “supposedly” will become available AFTER this batch of 12 A FET driver. And… BOTH drivers are considered “options,” which is odd to me. So sorry there are more questions than answer. But… if it were me, I would be tempted to PM Simon and ask if he could sell you a light with 8A Buck driver, and if not, when one would become available. Please post what you find. All IMHO anyone pls correct me as needed.
FWIW from Aliexpress web site:
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https://www.aliexpress.com/item/3256803593026491.html?spm=a2g0o.productlist.0.0.617f56fccm2YK8&algo_pvid=9f0cdbcb-813b-4257-8a45-f04709c4dfee&algo_exp_id=9f0cdbcb-813b-4257-8a45-f04709c4dfee-2&pdp_ext_f={"sku_id"%3A"12000029191064981"}&pdp_npi=2%40dis!USD!!30.96!30.96!!!!%402101e9d216560977625024165ec06f!12000029191064981!sea
12A FET driver, max output 12A, It is greatly affected by the battery voltage and internal resistance, and the current drops rapidly.
8A CC driver, constant current buck driver, As long as the battery voltage is greater than the LED VF value, the driver still maintains a high current output. In addition, the new 8A driver uses springs instead of copper posts.
Bead TIR lens makes the light much softer, The larger the angle of the lens, the more scattered the light.
Simon said 20 days for the 8A Buck drivers to be restocked and they will come with springs instead of the copper rod for the battery
It appears that Convoy does offer the S21D with sw35 D200 L2R 9080 LEDs. Agreed, it’s a terrific LED!
Only 20 days? All things considered if it were me I would wait for the Buck driver version.
Agreed. For the 219b, I think a longer constant 2A per diode is much preferable to a more transitory 3A (with hardly noticeable increase in lumens and associated increase in heat).
Of course, this is all hypothetical for me based on my limited understanding of how these two drivers operate. It would be great to see runtime/lumens graph for both configurations.
would you say the 519a 4500k de-domed is the rosiest CCT?
Yep so now Emisar 219b 3500k has competition with 21700 battery, and Simon also lists multiple CCT’s for 519a! Had I not already have so many lights that I don’t need :confounded: , I would not be able to resist. It feels like there’s competition between Hank and Simon and it’s great for us hobbyists.
The 219b 3500k has a warm golden light without any trace of green tint. It actually makes legendary 219b 4500k appear a little sterile (cold/”whitish”) in comparison. IMHO no Nichia collection is complete without 219b 3500k. :+1:
Comparison beamshots below; taken with Canon DSLR with white balance fixed at 5000k as always. Please note a close-up shot in total darkness like this “intensifies” the colors; in actual use, please imagine the color of each LED would “fade” and become much less intense/saturated, less “colorful” so to speak. I am sure I also have picture of the 219b 3500k shining on my living room (the wall of truth lol), will find and post later.
Amazingly enough the Opple is already here at the local office - unprecedented 1 week speed from China. I can hardly wait and fingers crossed they shipped the correct version, the Pro. It should be fun. :partying_face:
PS: I just checked the Aliexpress website link above and it seems as of today they are out of the Pro version again. If interested I think you just have to keep checking as it seems availability is on/off every few days. Really I am re-naming this as the Opple Hen’s Teeth.
None of my 519a are what I would call Rosy
sw45k is what I call Rosy:
519a dedomed cant touch this
Sure. It would make for a VERY interesting comparison of real world results of 2 different drivers, 8A Buck vs 12A FET, in otherwise-identical lights.
There are other aspects to consider, equally interesting. What if your usage is short duration on/off burst lasting for say, less than minute, and not constant on as in a runtime graph? Would the FET version be better because of more brightness despite of maybe worse runtime graph? What about battery, will high current capacity Samsung 40T now make a difference? Will the FET version be the brightest quad 219b ever, making it more useful as a walk light?
First person to do this comparison gets my vote for reviewer of the year 
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Yes, that would be a very interesting comparison.
And you are correct. Depending on one’s use case, the FET driver may be a better choice. If I need more lumens, I might also select a different LED… but would have give up the amazing 219b tint.
@Caleb, saw you posted this question on Convoy thread. I don’t follow forum closely so please let us know if you get an answer.
In posts above I almost talked myself into buying the FET 219b 4500k for the brightness :person_facepalming: 
, but must resist. It’s very hard for me not to click yes on something that’s 30 bucks, but really, way too many lights I don’t need.
The Convoy S21D with 219b 3500k is equally appealing. This is first offering of this beautiful R9080 LED with 21700 battery AND larger body with decent thermal mass (more prolonged brightness). Must also resist.
im not sure more thermal mass produces more prolonged output
but it might raise the thermally sustainable output, after stepdown…
look at the discharge curve… and where the output levels off…:
pic from this zeroair review
What I meant Jon is that because these lights all have automatic temp regulation, I think a smaller light with less thermal mass would reach upper temp limit faster and hence invokes step-down faster. The bigger light should have more prolonged brightness, especially at Turbo starting level.
Above is true in my admittedly limited experience of 219b 4500k in Convoy S21D vs Emisar D4V2. Granted there might be other factors (drivers, etc.) that affect brightness, but with both thermal limits set to 55, the Emisar dims not just to a lower level, but also does it sooner. (I still love my Emisar though because I like its tiny size and it’s a very pretty light.)
that makes sense
same difference happens when I put a 10A battery in a FWAA, compared to a 3A battery
The Opple Pro/Series 3 is here! A mere 10 days from China to my house in LA. It’s brand new and working as expected. Again, if you’d like to get one, just make sure it’s the item on the right side of the 2 pictures on the web site https://www.aliexpress.com/item/3256803116495145.html?spm=a2g0o.order_list.0.0.4f2f18026hLcUc, where under “Color” it will say Pro (please don’t ask me why it’s under “Color”). The other way to tell is of course the Pro is more expensive, ~$40.
The 1lumen review Cheap device to measure color temperature of light / flashlights (Opple Light Master 3 PRO ) is a good read on how to get started. Make sure you turn on “location permission” for the Opple app on your cell phone.
And this is the site where you calculate Duv Calculate Duv from CIE 1931 xy coordinates | Waveform Lighting
It’s a lot of fun and almost mandatory for Nichia collectors 
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The Nichia LEDs’ numbers measured with my Opple Pro are fairly consistent with known specs and findings of other posters.
For example the S21D with 219b sw45k - some preliminary trials’ graph & numbers below. The test may not add to what is already known, but still it is fun to confirm for yourself. OCD brains tend to have doubts and if that’s the case this Opple is a godsend .
FWIW this is Simon’s numbers (I believe) measured with the $600 Hopoocolor meter:
CRI for 219b sw45k Ra 96, R9 97, R12 79, DUV –0.0095
219b 4500k My numbers: CCT 4486 Ra 95.8, x 0.3582 y 0.3446 Duv –0.0087
wow, really close DUV results
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