SUMMARY & IMPRESSION
Convoy S21D w/ 219b 4500k
Beam & color/tint quality: Floody and bright for a Nichia light. Brightest in my small collection of Nichia’s and this plus the other Convoy S21D (with 519a) are the only ones that I feel are somewhat useful for our evening walk. IMHO this pair of S21D are the first Nichia lights that leave the “boutique” camp, and edge towards “functional.” As for color/tint, for all practical purposes it’s the same between Convoy and Emisar. For beam angle, Convoy is more floody and has less of a hot spot vs Emisar.
What’s so special about 219b 4500k? An unmatched ability to make more distinct different colors (green leaves vs light blue flowers of rosemary) and shades of colors (light green vs dark green of leaves). Scenes of plants and flowers show fantastic depth. Flowers “pop” against leaves. A joy to use if you like to observe and enjoy flora and fauna along your evening walk.
EDIT 12/2024: Convoy S21D is known and proven for having poor thermal regulation from a Turbo (100%) brightness start (other brightness level is ok). The light would step-down only once to about 40% brightness and there it would stay as temperature shoots past the limit of my IR gun (60 F). In comparison, other lights w/ proper thermal regulation would step down further to lower temperature, but not the S21D, which again only steps down once, to ~40% brightness. It gets extremely hot.
Specs Absolutely eye popping: Ra 96, R9 97, R12 79, DUV –0.0095
Construction & cosmetic: “Functional,” in an industrial way :innocent: . One example: there is really no knurling to speak of and flashlight therefore just a tad slippery. Doesn’t feel solid like my Olight (the best among my lights) but then the cost of 1 Olight equals three (!) Convoy S21D’s so I’m not complaining.
Design & Use:
21700 battery, which means a larger body than Emisar, but still only about size of my Olight M2R and still pocket-able.
The LiitoKala 21700 battery that comes with the light shows 4877 mAh and internal resistance 52 with my Opus. I don’t know max current draw of this battery but it works fine.
No Anduril, which is a plus or minus depending on your point of view. I prefer Anduril.
No Anduril also means nutty hobbyists cannot play with settings such as thermal regulation’s max T (factory setting is 55 C per Simon), but then judging by the result, maybe we don’t need to.
Rear switch only - I prefer side switch for this type of light but again, personal preference.
Comment The Convoy at 30 bucks is an incredibly compelling flashlight. A deserving backbone for any light collection if beam quality and color are priorities. Nichia 219b sw45k LED is discontinued so who knows how long supply will last; if you’re interested I would buy it quickly. IMHO if there is one Nichia light that you should buy, it’s this one, primarily because of its lasting brightness. The give away price and 21700 battery don’t hurt either.
Convoy S21D w/ Nichia 519a 4500k (Note: actual CCT measurement is around 3800-4000k)
Beam color: Everything stated above about S21D with 219b applies here, EXCEPT beam color. Whereas 219b has that famous rosy/magenta tint (a result of a negative, below BBL Duv) that every hobbyist loves, 519a has a warmer, more yellowish/golden tone (a result a positive, above BBL Duv, plus a much lower CCT than spec). During comparison, I actually was struck at how different 519a is to 219b.
519a is recommended because of how different its beam color is from 219b, and yet it still has spectacular CRI specs ( Ra 93.6, R9 82, R12 80, Duv 0.00091). While 219b has incredible and un-matched color rendering, sometimes the magenta tone of 219b might be too much for me :-), and 519a’s golden tone provides a relief. OTOH if you don’t like a slight golden tint, this is not the LED for you. I love it because for me it’s like having different wines or food from different restaurants, all good yet different. I guess it’s called having fun with a hobby :innocent: .
Otherwise, from my test using photography and checking light level, this and the S21D with 219b are the two brightest in my small collection of Nichia lights. The 2 are the most useful light for practical use because of their brightness and would make a wonderful back bone to any light collection in which beam color/quality is a priority.
Emisar D4V2 w/ E21a 4500k
I’ve come across post where someone waxed poetic about this E21a LED like it’s the second coming, and I’ve come across post where it was the worst LED the person had ever seen. Based on my pictures and of course live view observation, IMHO this LED is extremely close to beam color of the 219b 4500k, but very slightly more yellow. Of note Emisar needs to use frosted optic Carlo 10623 for the E21e to smooth out the beam, but this frosted optic results in a dim hotspot, too dim for me. I’ve tried the clear optic Carlo 10622 with this light, but then the beam has a yellow greenish ring at corona (see pictures later in this thread HERE). 219b has no such problem using the same optic. Unless you see something that you really like, personally I would pass on this LED and get the 219b instead.
Emisar D4V2 w/ 219b sw45k
Beam & color/tint quality: Floody with a central hotpot that is brighter than Convoy at Turbo start, but after just a couple minutes, step-downs occur and brightness begins falling behind Convoy. The useful part of the beam becomes very small and hence not much area is covered (you could see the difference between the 2 lights in the beam shot below). This is observed in a D4V2 that has been calibrated and max temp limit raised to 55.
Construction & cosmetic: This is one of the most popular lights for hobbyists for good reasons: it’s pretty, construction quality very nice, a notch above Convoy. The auxiliary lights are fun. I enjoy taking pictures of this light; it’s a great gift light.
Available in 4 anodized colors, plus brass, copper, titanium material available. All very pretty. Keep in mind copper and brass are very heavy. Almost too heavy.
Design & Use:
18650 battery, which means a very nice small light that fits nicely in the hand. But, will a 21700 be coming?
Anduril 2
Side switch: One of the nicest I’ve used, clicks nicely and clearly. I have one with the raised ring around button option, and I don’t like it at all.
Comment Emisar sells 219b and E21a lights in several different CCT’s. This means you ARE going to end up with an Emisar one of these days 
. To be at Emisar’s web site (oddly named www.intn-outdoor.com) makes me feel like a kid at a toy store Christmas time. I applaud Hank’s effort to supply us with such a dizzying array of fun lights.
Convoy S21F
This is Convoy’s first variable CCT light using Nichia LEDs, 519a 2700k and 519a 5700k. The magic of mixing is that Duv becomes lower than either LED, meaning this light should be among most rosy 519a beam and lowest Duv you could find, particularly in the middle area 4000k or so.
The output is U shaped, meaning output is high at either end, 2700k & 5700k, and lowest in the middle area around 4000k. The once exception is Turbo mode. Turbo mode is only available by double clicking, which takes you to 2000 lm with CCT 2000k. The Turbo beam is literally pink from the low Duv; it is very pretty and very unusual and alone could be reason to buy this light.
Except for Turbo mode at 2800k, at all other CCT’s this light is not as bright as S21D.
USB-C charging and side switch makes this the most used of my Nichia lights. Highly recommended.
Convoy M21B with B35AM: My nickname for this light is “219b with throw”. There are two LEDs in my collection that look like the famous 219b 4500k: first is E21a, and second is this one, B35AM. Amazingly enough it manages to beat big brother 219b in its own game, with the highest CRI I’ve ever seen, Ra 98 and R9 clocking in at 99. It is the rare pocketable Nichia light with outstanding 260 m throw, unique in this aspect and that’s why it’s a must-have for me. Noticeably lower output than Getian GT-FC40 LED, but more beautiful rosy tint, that’s the trade off between BAM and FC40 lights. Tint wise: B35AM is less rosy than 219b but still very much a rosy tint. Sustained brightness is fantastic making this an eminently useful walk light.
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