I can see what you mean, the center of the beam has less focused brightness than the perimeter of the hotspot… when looking at the beam on a wall…
I dont think it has anything to do with the LED… as you noted, changing the optic, eliminates the difference in beam focus in center vs perimeter of hotspot.
fwiw my Two Fwaa, regardless of which LEDs I use, also has less brightness in center, than perimeter…
I think it has to do with how the optics are focused… not exactly the same in the middle as on the edges… I agree there is a trade off, if we use optics that blend the beam more, it also gives less throw. There is no perfect beam, there are always compromises, depending if the light is used at close range, such as indoor distances, vs longer range, such as outdoors.
I hope you can enjoy your lights, in actual use, despite the beam not being perfect, on a wall.
You need to try other optics too with it, the default one is most likely not what you are looking for, especially to try the other if you don’t like the close up beam.
With the flashlights you have mentioned you do not have optic choices and you are not missing any perceived throw because there is no optic that claims the most candela.
Also you are comparing 9LED optics and 12LED optics with the dual channel D4v2 which is rather 2 LEDs offset in an optic which is kind of know to have a discrepancy that you have noticed on a wall.
FF-light PL47G2 with 219*b*4000k produces a perfect beam with 30 deg lens and just 4 emitters. But my D4v2 219*c*4000k there is a similar problem (again, with 4 emitters).
I bet it worth trying then to sand off the legs of the lens to bring it a bit close to the emitter? (or does it already sit right on top of it?)
I do not have the 219B model but I do have a couple SST20 and they do not have that darker area, one default optic and one frosted optic, the frosted optic (10623) looks nicer for me personally as the hotspot is bigger.
Do you see that with the eyes or you take the camera and expose for the hotspot (thus underexposing the rest) and only see it in the photos?
These optics have a 2 step leg, so the legs rest on the MCPCB, with a narrower diameter smaller part of the tip of the leg fitting inside the MCPCB.
You can still shave the leg if you want but they will not grip into the MCPCB anymore after that.
I don’t want to shave the legs off fully, just some of it to bring the lens closer to the emitter. I guess I’ll order spare lens and try that
Why my eyes of course. If these dark discolorations weren’t bugging my eyes I wouldn’t bother. But I see them and hence this thread. Just trying to get non-frosted D4v2 with a clean beam.
I’ll try my luck with SST20 as well then. I also heard Hank’s SST20 @4000k come from a nice rosy bin.
Does anyone else with a D4k have this problem, what optics are you guys using for your 219B d4k? My stock 10622 has this and looking for solutions. Is the 10621 any better? Hesitant to put the frosted 10623 because of the loss of throw
It’s a problem with phosphor distribution being uneven. The 10621 likely won’t improve it at all (it’s also a clear optic), I’m afraid the only way to get rid of the dark spot is to mix up the beam with frosted optic (10623).
It’s either a quality control problem on Nichia’s part, or that Nichia simply does not care about phosphor distribution, since it is not one of the parameters promised by the datasheet. It’s hard to say what will happen if you order the same emitter, whether it resolves the issue is entirely up to luck as even adjacent LEDs in the same reel can have completely different phosphor distribution.
I would just use the frosted optic and forget about it. If you want more throw you can even de-frost it a little by polishing it on soft clothing.
Agreed that the 10621 will probably not be better.
First, I would try with frosting the 10622 optics. You can do this with some sandpaper. Start with some higher grit and if necessary, go lower to frost even more.
You could also replace the LEDs with some Convoy 219Bs. Every one I’ve gotten so far from Simon have been great.
I have quad 219Bs with 10621 and 10622 optics in other flashlights and the beams are great. The host shouldn’t matter that much in regards to the beam, but the optic, LEDs, and the MCPCB do. It appears the Hank board has very similar LED offsets as the MTN, which is what I have.
With triple Carclo optics, the position of them on the MCPCB will also make a difference with the beam. Just last night I changed the rotation of a 10511 on some sliced SST-20s in order to improve the beam. You could try the same with your quad.
Wanted to add that a convenient way to get sandpaper in a variety of grits is to visit the beauty section of your local supermarket and look for nail buffing blocks. Some of them have multiple faces each with a different grit and can be had around $1-2.
I’m not a particular fan of the 719A, as it somehow manages to have both lower output AND lower CRI compared to 519A at the same power. And the stacked-die thing that’s supposed to triple intensity was a total flop. Nichia could have just released a factory-domeless 519A which would be better in every way.
The 219C-V2 would be an interesting emitter, but from what I’ve seen it’s also R9050 and has a smaller die, so it won’t handle as much power as the 519A/FFL.
