My 21700 sofirn c8f got only 7.22A used UT210E clamp meter and got 2,678 lumen. I use fully charge sofirn 21700 4000mah battery that come with the lights.

What is the price on the 21700 C8F? Are they still for sale?

This would be my first 21700 light and have always thought that the 21700 would fit the C8 better anyways.

I think you can get it for around the same price at Amazon with their coupon.

Also, know TA he may want to order 2x hosts for the same price from their aliexpress shop

contactcr wrote:

I think you can get it for around the same price at Amazon with their coupon.

Also, know TA he may want to order 2x hosts for the same price from their aliexpress shop

Looks like my reputation proceeds me lol.

Finally have my 21700 C8 host working with the rubber boot installed. I had made a shim to be sure the boot wasn’t holding the button down, didn’t work. So today I used my Proxxon rotary and carefully reduced the length of the brass post coming up out of the switch. Put the boot in (shim still in place) no worky. VERY obvious space between the post and boot, but no good. Without the boot it works fine. So, I looked around on my table and found the black plastic tray some FET’s came in. What they call the “tape”. I cut the bottom out of one of the containers and placed this inside the boot, removed the shim, put the light together… and it works! The rubber is soft enough that the switch depression rebounds and Anduril doesn’t recognize the press. So now with this thin bit of plastic in there it gives a positive enough click that Anduril sees it and the light works fine. Go figure…

This only happens with Anduril?

So far as I know, Anduril seems to have a higher sensitivity to the button press timing…

Texas_Ace wrote:

What is the price on the 21700 C8F? Are they still for sale?

This would be my first 21700 light and have always thought that the 21700 would fit the C8 better anyways.

I think 6-emitters would be the grail C8. I think LED4Power is coming out with a kit for the Sofirn 21700 C8F. Hopefully Kiriba-ru will make a copper spacer for this as good heat sinking is critical if we want to max the output.

SKV89 wrote:

I think 6-emitters would be the grail C8.

Someone made a 7x reflector C8. But the head is huge. Don’t think we can fit more than 3 reflectors in a practical C8 form factor. Why is TIR bad? I think you only lose 5-7 % output compared with reflector.

I MUCH prefer TIR optics over reflectors as a rule. You might loose a few OTF lumens but you gain a much more usable beam.

I did countless tests between TIR and reflectors a few years ago and almost every time I decided I preferred the TIR.

In today’s world of LED’s with rampant tint shift issues, the TIR is even more important for me. A beaded surface TIR can eliminate almost all tint shift with minimal effect on OTF lumens or even the beam shape.

That 6x C8F looks quite interesting, I would be down for 1 of those.

Skylumen Vinh said he loves TIR too. I’m guessing the real drawback is you can’t make a TIR light throw as well as with reflectors.

SKV89 wrote:

Why is TIR bad?

I’ve heard there are certain TIR lenses that give a reflector like amount of spill, but I haven’t tried those or know what model they are.

If someone wanted 6 emitters, there’s no need to convert the C8F, just buy a Emisar D4S, DQG Tiny 7x, etc… There are plenty on the market already so converting makes no sense to me.

SKV89 wrote:

Skylumen Vinh said he loves TIR too. I’m guessing the real drawback is you can’t make a TIR light throw as well as with reflectors.

In that testing I mentioned earlier, I generally got about the same or better throw from a good TIR as an equal sized reflector. The difference is that the TIR had about 2x the hot spot size.

JasonWW wrote:

SKV89 wrote:

Why is TIR bad?

I don’t like the lack of spill they give. All the light seems to go straight ahead and when walking at night you can’t see your feet and where to step or things to your left and right. I have the DQG tiny 7x and I have to wave it around to see. A reflector based light I can hold steady in front of me.

I’ve heard there are certain TIR lenses that give a reflector like am out of spill, but I have tried those or know what model they are.

If someone wanted 6 emitters, there’s no need to convert the C8F, just buy a Emisar D4S, DQG Tiny 7x, etc… There are plenty on the market already so converting makes no sense to me.

In that extensive testing I did, I found that a lot of TIR optics that were not aimed at pure throw give about the same amount of spill in the real world out to most of your vision range. Particularly the frosted or beaded tir optics.

The difference was at the very edge of the spill, the reflector would have a sharp cutoff and it would be brighter at the edge where the TIR would fade out, making it appear not as bright.

If you use a frosted tir optic on the other hand it can easily have more spill then a reflector, which is another nice thing about TIR optics, you can pick the beam that is right for you.

For example I prefer the 10511 triple optic over the more common 10507, it is a bit more floody but gets rid of tint shift and I find the beam more pleasing.

If you have a triple 20mm light, I would recommend getting all the various optics for it from the floody to the frosted models and trying them out.

I’ve built many a light, with all kinds of set-ups… and I much prefer a reflector as compared to an optic. Of course I have plenty of optic triples and quads, but I also have triple and quad reflector lights. I have more than a few single TIR lights as well and it goes without saying that a majority of my lights are single reflectors. Hands down, I prefer a reflector. The pebble faced optics like an Ledil CUTE-3, I sand smooth and polish clear. I do like the look of the honeycomb, but I like to see inside much more. On the short side of a thousand builds, I prefer a good well made reflector and a high quality dual side AR coating.

SKV89 wrote:

I think 6-emitters would be the grail C8. I think LED4Power is coming out with a kit for the Sofirn 21700 C8F.

Would buy immediately! For example 6 * XPL-HI TIR 4000-5000K. I like C8 much more than D4S

Upgraded with NOCTIGON 4XP 33MM MCPCB & NICHIA NVSW219CT R9050 D260 and Ledil Angie-S Quad LED optics
Pretty cute turned out  : BLUSH:

johnkey68 wrote:

Nice mod John, I wish I could make adapters like that!

That is nice! Great looking finished product, way to make use of the new Noctigon board and it’s accompanying optic.

Wow… that is a really sweet mod there johnkey68 Been looking for a suitable host for the new Noctigon quad board/optic and my 30T cells I have laying around. Is the pill you made a press fit, it looks like you followed the profile of the inside of the host/head for a tight fit?

Wow John, that is amazing! You might want to consider selling a kit . Maybe make the spacer out of copper too. I think the C8F is a better host for a quad than the D4S because it has more mass for heat dissipation.

A kit sounds good

Hey Sofirn C8F 21700 owners!
I am looking for floody single cell light with high capacity and good heat transfer.
I am not (so much) interested in maximum lumens, but I am interested in how much lumens C8F can pump out in continuous use without heat throttle and how many minutes its 4000mAh battery lasts in that mode.
Would 5000mAh 10A battery work with it in my use?
Do you know any similar lights around same price range that could be better for my use than the C8F?
Some other battery type flashlight maybe?

The Sofirn SP31A would be a good bet in the 18650 realm.

Since it uses a buck driver and an XPL2, it is a very efficient light, and still throws quite well, and can maintain its brightness for a long time. It also has a big heatsink, so you can hold the 1000 lumen turbo for quite a long time. It also uses a dual switch setup like the C8F 21700, which is very useful.

If you want something big and with a lot of runtime, I would recommend the SP33. 26650 light. You can get a 5500mAh 26650 for very long runtimes.

The C8F is a hotrod light mainly, so the lumens will go down if you use it above low brightness, and can get extremely hot.

Hey you! You did bring me here from reddit
How long of a time are we speaking of with “quite a long time” as second highest mode on SP31A is 350 lumens which seems bit low maybe, would it stay on that mode untill battery goes out? Ofc I do not know what is realisticly possible on this size flashlight. Anyway that is more than C8F’s low which is 100 lumen. 700 and 500 lumen modes will eventually throttle down to 100 lumen with C8F yes?
SP33 looks quite nice too, but will it stop thermal throttling on 500, 250 or 45 lumen mode?

350 lumens should easily last 3hrs of constant brightness since it only pushes a bit less than 0,95A to the emitter on the SP31A.

It won’t probably thermal throttle on the 500 lumen mode, and it will step down on the timer, but you will be able to get the 500 lumen mode back up.