I should have added the qualifier that the beam shape depends on the precise TIR used. The only TIR I currently use is the Carclo triple, which does make a square beam out of a dedomed LED. This happens because the central circle of each individual TIR is actually a miniature convex lens, which projects the square shape of the emitter. The Carclo quads behave the same way, hence the PCB design.
TIRs that do not have this tiny convex lens in the center might give a more circular beam.
Try holding the light on low only a few inches away from the wall, you will see the square emitters projected. Obviously this effect greatly diminishes the further away from the wall.
Thanks for explanation, and making me realize I’ve misspelled Carclo all this time. 
The world of flashlight is a lot more complicated the more I dig into it. I have spare Carclo 10621 Quad, the throwy one. If I experiment and paint three of the Quad black, I imagine I would see what a single one does?
For a less permanent solution, stick some black electrical tape over the front (covering just the LEDs you want to block).
By far, my most favorite mode of S21F is Turbo. For 3 reasons:
as I could not tell when PWM is on or off.Here’s comparison of S21F’s turbo mode with the closest CCT, my S21D 519a 4500k which measures 3900-4000k. I hope you could see how S21D is more yellow vs S21F’s more rosy tint. Both excellent, just different.
That S21F’s tint for me is almost worth the price of admission of the light, especially for Nichia “collectors.” I don’t know if there is any ~3800k CCT Nichia that has such negative Duv.
S21F best Convoy Light IMO!
“1. There is a large step between 2/4 and 3/4 brightness. 2/4 brightness should be ideally around 150-200 lumens instead of 50-60 lumens.”
Hello
in the review I read that the 2nd mode is 65 lumens
Did the second version of the flashlight fix this mode? How many lumens does it currently put out in the second mode?
Hi which review is this please? I’m not getting such low numbers with either of my 1st batch or 2nd batch light. Measurements from my TA lumen tube:
1st batch S21F:
2700k end: 15-136-500-1047 lumen
5700k end, which only has 1 LED working: 8-74-275-576 lm
2nd batch S21F:
2700k end: 17-143-531-1124 lm
4500k mixed: 19-165-623-1094 lm
5700k end: 20-173-651-1387 lm
S21F 2/4 mode 5700k - 65 lumens.
thanks for the info
Simon replied that he released only one version of the driver for S21F
Probably still the inaccuracy of measurement in this review
Just kidding, I had to do a bit of work with my hands. I have machines, so it took about an hour. If completely manually, it will take about 6 hours.
Walked a flashlight into the forest.
The light looks really nice. Beautiful work on the body.
interestingly, this 219b from Simon is more pink than from Henk, even it seemed to me too much, Hank has a clean neutral without pinkness, but here it’s an amateur, I see such pinkness for the first time, I also have it from Simon, it’s not so pink there. Well, here I specifically asked him to be pinker in order to understand the essence 
Very nice! For a moment I thought that was a stainless host…great job on the polishing. Sometimes the alloys used for flashlights don’t polish up so nicely even when you do it right, but this looks excellent. No cutting, correct, just polish? Did you do it with a lathe, or a bench wheel, or by hand? That really does look great, nice work.
Thanks I was trying!) Tactile flashlight has become very pleasant, smooth, do not want to let go
First I removed the anodizing from
of the old tape (grain 180) on the surface grinder, twisting the flashlight in his hands along the tape, there were traces of grain, then he clamped it in a vice and polished it with sandpaper 1200 for about an hour, it took 3 sheets, the traces of the adhesive tape disappeared, but there was no shine, went to the polishing machine with a rag circle and paste, at first rough, it almost began to shine, then polished and the body shone!
I am engaged in the manufacture of knives, so I have the equipment, this effect can be achieved simply with sandpaper, paste and a woolen sock, preferably clean)
Welcome to the 219b club. Beautiful job on the light!
Another difference might the optic. The most diffused Carclo optic I’ve used for my D4V2 is 10623, and the beam profile (throwy vs floody) of this Carclo is similar to my Convoy’s 30 Bead. (Based on the numerous pictures I’ve taken with these lights and optics.)
Basically Convoy 60 Bead is the most diffused optic possible among my Nichia lights, and Carclo’s equivalence might be 10624 which I have no experience with.
Thank you.
I go to the forest, I use a clean 10 degree, sometimes you need to light it further away, suddenly someone is sitting there)
60 is already very wide, great for a photo or at home, but in nature even 30 is wide for me.
I need to correct myself: Carclo does have 10624, which should be more diffused than 10623.
As mentioned, for beam profile (throw vs flood):
Carclo 10623 = Convoy 30 Bead (approximately, IME & IMHO)
Carclo 10624 = ?
The more diffused optic makes the beam color more homogeneous AND more magenta/pink IME.
Nice Machiny !
Hand polishing with a woolen sock…now that is dedication!
I used to polish a lot of aluminum. It took a little learning since it is so different than steel - and it also depends on the alloy. I smoothed until starting with 600 grit, then 800, 1200, 1500, and 2000. More abrasive needed but faster than all the time spent at the machine. Firm muslin rag circle with white (white diamond) compound was usually enough, only sometimes used soft red compound for super glossy shine.
Thanks for sharing your work! Nice to see.
