Not too long ago I was nit picking and memorizing lumens and throws of Amazon flashlights, looking for a bright light for our evening walk along a nature trail in our neighborhood. Since then, the hobby somehow has made an abrupt left turn towards color quality of the beam , and here I am with a bunch of Nichia’s, generally considered the “best” in the business when it comes to color quality and accuracy (CRI). These new “hobby” flashlights couldn’t light up the path like my Nitecore MH12S or Olight M2R Pro Warrior, as they have little throw to speak of. What they do have is color-rendering accuracy and a unique ability to make colors “pop,” for example green leaves & colorful flowers along the trail more distinct and beautiful. Every shade and every color stand out from each other. That’s why I buy them and honestly at 30-60 bucks a light it is difficult to resist the temptation. Collecting Nichia lights has been such a wonderfully inexpensive hobby compared to some of my previous financially disastrous ones like sports cars and high-end audio :-).
The Convoy S21D is a 21700 light only recently released. Two LEDS are offered at the time of this writing: Nichia 219b and 519a, both @ 4500K CCT. The 219b LED with its beautiful rosy/magenta tint needs no introduction and likely has the most number of obsessed owners in this hobby. OTOH Nichia 519a is a newer, larger LED (nearly twice as big die size) and would make a very interesting comparison. I ordered 2 Convoy S21D’s with Nichia and a Convoy M21B with GT FC-40 without any problem, but now they don’t seem to be not available on AliExpress. I believe banggood.com also has them, but cost may not be as low.
The other flashlight used in this comparison needs no introduction either; it’s the incredibly popular Emisar D4V2. Emisar is a heaven for 219b fans, offering multiple CCT versions of this LED, but it doesn’t have 519a, yet. OTOH Emisar does have the Nichia E21a, a LED that is also highly regarded, but is not nearly as popular (see discussion #3 below for possible reason why). Of note Emisar uses 9 amp Constant Current driver for 219b, but only 5 amp for the E21a.
I’m adding an index of the interesting or fun posts that I’ve wasted the most amount of time on . Hope it helps for anyone looking to waste time reading about Convoy.
* 4 Lights I would buy were I to start from beginning Click here
* Important: Throw numbers and comparison of TIR optics for Convoy S21D and Emisar D4V2 Here
* Convoy Accessories Here
* Summary of Impression of 219b 4500K vs 519a 4500k vs E21a 4500K Here and photographic comparison with E21a 4500K Here
* Convoy S21D or Emisar D4V2? Which one should I buy? Here
* Comparison of Effects of Convoy “Green Reflection AR Lens” (it’s a reflection not a tint) on Duv (it makes Duv about 20 points more negative) Here and white-wall beamshot Here
* Duv dropping ~20 points as Nichia 519a LED heats up with time Here
* Specs: CCT, Ra, R9 measured by Simon, and some by me Here
* Convoy headlamp H2 with beautiful Nichia 219b 4500K & 3500K Here and headband Here
* Great Sustained Brightness of Convoy S21D and M21B-E-F Here vs D4V2 Here sustained brightness from Turbo Here
* 8A Buck Driver versus 12A FET Driver - comparison of brightness and runtime graph Here
* B35AM 4500k in M21B: Fantastic light, a rosy Nichia light with throw! Here
* Nice Discussion of Flashlight’s Driver Discussion Here
* Nice Discussion of Reflector and effects on Hotspot, Corona, Spill Here
* Convoy Temp Regulation Algorithm Here
* Calculation of CCT when Mixing LED CCT’s Here and Weighted Here