Sofirn SF13 2×AA - First Impressions

kikkoman · 2019-02-25T22:33:56.000Z

Can anyone confirm the manufacturer’s runtimes ? They just don’t seem right.

Do they really mean a “900mAh Alkaline AA”? Not 1900 (which would be expected out of a typical Alkaline)? Either they _did _test with 900mAh cells and runtime with normal cells or Eneloops should be twice as long (probably not on Turbo), or they really meant 1900mAh and the driver is horribly inefficient - something I don’t expect with a 2xAA light.

I’d really like to know, because that would mess up an otherwise pretty nice light.

LEDlove · 2019-02-25T22:40:26.000Z

kikkoman:

Can anyone confirm the manufacturer’s runtimes ? They just don’t seem right.

Do they really mean a “900mAh Alkaline AA”? Not 1900 (which would be expected out of a typical Alkaline)? Either they _did _test with 900mAh cells and runtime with normal cells or Eneloops should be twice as long (probably not on Turbo), or they really meant 1900mAh and the driver is horribly inefficient - something I don’t expect with a 2xAA light.

I’d really like to know, because that would mess up an otherwise pretty nice light.

I think there may be plenty of inaccuracies in their figures considering how their instruction manual reads. Lots of mistakes in translations makes the manual kind of amusing. In mine, it seems to state that the flashlight was used in a rainstorm when referring referring to the waterproofing. As for their runtime figures, it was noted earlier that the 8 lumen low level was probably closer to 15 or 20 lumens. For the record, I wondered about that 900mah figure as well. That’s more like what you’d get from a AAA battery.

All in all, for the price they are charging, it’s really nice. Far better than anything I’ve seen in stores for the same price, or even more. It’s what caused me to make my very first online purchase of a flashlight.

Barkuti · 2019-02-26T01:28:23.000Z

Remember they used protected AA alkaline battery. Protected and a single one LoL.

Jokes aside, alkaline cells are a really poor choice for anything remotely high drain. At 0.5A an AA alkaline will already deliver less than half of its peak capacity and if you go even higher they'll plummet in a flash. Maybe this is why they say “900mAh :-D alkaline”.

Cheers ^:)

peg_matite · 2019-02-26T01:54:05.000Z

Looks a good bit like the Zanflare F2.

LEDlove · 2019-02-27T19:51:54.000Z

peg matite:

Looks a good bit like the Zanflare F2.

I don’t think it’s all that much brighter either. I got mine last Saturday and have been doing some more comparisons at different distances and in different environments and I don’t think it’s as bright as they say. When I compare my 130 lumen energizer to the Sofirn SF13 in turbo mode, it’s about twice as bright, which would put it at 260 or maybe 280 lumens. Even if it was 320 lumens, it’s still 100 lumens lower than what the unit I have is advertised as. I think I either got the older version, or the 420 lumen figure is based on using 14500 cells instead of AA, even though they specify AA.

Serlite · 2019-02-27T20:00:33.000Z

LEDlove:

peg matite:

Looks a good bit like the Zanflare F2.

I don’t think it’s all that much brighter either. I got mine last Saturday and have been doing some more comparisons at different distances and in different environments and I don’t think it’s as bright as they say. When I compare my 130 lumen energizer to the Sofirn SF13 in turbo mode, it’s about twice as bright, which would put it at 260 or maybe 280 lumens. Even if it was 320 lumens, it’s still 100 lumens lower than what the unit I have is advertised as. I think I either got the older version, or the 420 lumen figure is based on using 14500 cells instead of AA, even though they specify AA.

I know I’ve read somewhere around these forums that perceived brightness doesn’t correspond consistently with actual lumen output. Stuff like how a light that’s technically twice as bright as another only appears 1.5x as bright, or something like that. So it could actually be outputting closer to 420lm, but only appearing twice as bright as 130lm rather than three times as bright.

SIGShooter · 2019-02-27T20:02:42.000Z

LEDlove:

peg matite:

Looks a good bit like the Zanflare F2.

I don’t think it’s all that much brighter either. I got mine last Saturday and have been doing some more comparisons at different distances and in different environments and I don’t think it’s as bright as they say. When I compare my 130 lumen energizer to the Sofirn SF13 in turbo mode, it’s about twice as bright, which would put it at 260 or maybe 280 lumens. Even if it was 320 lumens, it’s still 100 lumens lower than what the unit I have is advertised as. I think I either got the older version, or the 420 lumen figure is based on using 14500 cells instead of AA, even though they specify AA.

Using 14500’s in the SF13 will likely result in magic smoke since the driver is rated at 1.6 to 3.2v. Even a single 14500 with a dummy cell will be over the rated voltage so I highly doubt they used 14500’s in their rating.

LEDlove · 2019-02-27T20:09:28.000Z

Serlite:

LEDlove:

peg matite:

Looks a good bit like the Zanflare F2.

I don’t think it’s all that much brighter either. I got mine last Saturday and have been doing some more comparisons at different distances and in different environments and I don’t think it’s as bright as they say. When I compare my 130 lumen energizer to the Sofirn SF13 in turbo mode, it’s about twice as bright, which would put it at 260 or maybe 280 lumens. Even if it was 320 lumens, it’s still 100 lumens lower than what the unit I have is advertised as. I think I either got the older version, or the 420 lumen figure is based on using 14500 cells instead of AA, even though they specify AA.

I know I’ve read somewhere around these forums that perceived brightness doesn’t correspond consistently with actual lumen output. Stuff like how a light that’s technically twice as bright as another only appears 1.5x as bright, or something like that. So it could actually be outputting closer to 420lm, but only appearing twice as bright as 130lm rather than three times as bright.

You could be right.

LEDlove · 2019-02-27T20:11:47.000Z

SIGShooter:

LEDlove:

peg matite:

Looks a good bit like the Zanflare F2.

I don’t think it’s all that much brighter either. I got mine last Saturday and have been doing some more comparisons at different distances and in different environments and I don’t think it’s as bright as they say. When I compare my 130 lumen energizer to the Sofirn SF13 in turbo mode, it’s about twice as bright, which would put it at 260 or maybe 280 lumens. Even if it was 320 lumens, it’s still 100 lumens lower than what the unit I have is advertised as. I think I either got the older version, or the 420 lumen figure is based on using 14500 cells instead of AA, even though they specify AA.

Using 14500’s in the SF13 will likely result in magic smoke since the driver is rated at 1.6 to 3.2v. Even a single 14500 with a dummy cell will be over the rated voltage so I highly doubt they used 14500’s in their rating.

I guess I won’t be trying that then. I’m using 1.2V NiMH batteries instead of 1.5V alkalines. I haven’t tried alkalines yet, but maybe I should do it to compare if they’re a bit brighter due to the 2 alkalines having a combined increase of .6 volts over the NiMH.

BlueSwordM · 2019-02-27T20:17:56.000Z

They won’t be brighter, at all.

See, alkalines have very high internal resistance.

That means for anything over 50-100mA, they lose a ton of capacity and a lot of power.

Also, their discharge is more of a linear curve, as they fall very quickly down from 1,5V, while NiMH stays at 1,2V average voltage for the entirety of the discharge.

TLDR: LSD NiMH cells crush everything alkaline does, even matching it in long term self-discharge.

LEDlove · 2019-02-27T20:21:22.000Z

BlueSwordM:

They won’t be brighter, at all.

See, alkalines have very high internal resistance.

That means for anything over 50-100mA, they lose a ton of capacity and a lot of power.

Also, their discharge is more of a linear curve, as they fall very quickly down from 1,5V, while NiMH stays at 1,2V average voltage for the entirety of the discharge.

TLDR: LSD NiMH cells crush everything alkaline does, even matching it in long term self-discharge.

This explains why my digital camera actually works with NiMH batteries while alkalines won’t work for more than a couple minutes after putting fresh ones in the camera. The alkalines still test as very good, but my camera sees them as dead.

LEDlove · 2019-03-03T22:18:37.000Z

Phlogiston:
Could you please tell me how to turn the light on in low mode? The instructions say that “fast clicking” it on from when its off activates memory mode and turns it on in the last mode it was in. But for me, it comes on in the last mode it was in no matter how slowly I turn it on. Sometimes I want it to come on in low mode, but comes on in turbo if that’s what I last used.

Jackie · 2019-03-04T02:28:38.000Z

good small light, i bought one last month, and it update to 420lm already

Hellie112 · 2019-04-08T15:44:03.000Z

Hellie112:

The second unit I received had more glue inside and was a lot harder to open.

Just received two SF13 “420 lm version” (ordered during the spring sale for giving away to friends). And I can report that the bezels on these two units aren’t glued.

SKV89 · 2019-04-09T00:25:53.000Z

Bezels arent glued. I modded three of them last week with e21A 9080 and Optisolis. Works well except I dont like the UI as much as the SF14

Phlogiston · 2019-04-08T23:37:43.000Z

LEDlove:

Phlogiston:
Could you please tell me how to turn the light on in low mode? The instructions say that “fast clicking” it on from when its off activates memory mode and turns it on in the last mode it was in. But for me, it comes on in the last mode it was in no matter how slowly I turn it on. Sometimes I want it to come on in low mode, but comes on in turbo if that’s what I last used.

As far as I know, there’s no short cut to low. The light always uses mode memory.

The manual’s not very good, shall we say. Just as an example, the German part of my manual actually refers to a completely different light!

iamlucky13 · 2019-04-09T05:30:48.000Z

SKV89:

Bezels arent glued. I modded three of them last week with e21A 9080 and Optisolis. Works well except I dont like the UI as much as the SF14

Which PCB are you using for those mods? Is that for both the SF13 and SF14?

What are you using for an optic/reflector, and does it work reasonably well with the Optisolis?

If you’ve come up with a good combo, this seems like a cost-effective way to get rare emitters into practical lights.

SKV89 · 2019-04-09T14:50:55.000Z

16mm vr16 mcpcb from virence.com. I buy them presoldered. It fits the sf13 and sf14 v1 but does not fit the sf14 v2 because they decreased the mcpcb to I think 15 or 14 cm. Too bad the sf14 v1 not available anymore.

hank · 2019-12-31T03:04:29.000Z

the one I received 2 days ago is the 420 lumen version.

I’m curious where the difference arises between the second 420 lumen version, and the first SF13 320 lumen version.

That’s about a $3 price difference, while both versions are still available.
Better driver design? Both claim XPG2; any way it’s a better emitter?

I’m thinking at least these look easy to mod, as I like to swap in amber emitters.

EDIT: I asked Sofirn and was told there’s no difference between v1 and v2.
Curious, that.

hank · 2019-12-28T17:38:24.000Z

Strangely, strobe is specified at 420 lumens for 28 minutes, just like turbo, when I’d expect longer, given that the light is off and presumably using less power between flashes.

I have a hunch about that: cycling the driver on and off probably takes a lot of power relative to keeping the LED illuminated.

I recall many years ago reading a comment from Gransee (in a discussion at CPF) who originated the Arc AAA lights — saying that once the light dropped into moon mode due to low battery, you’d get more light for longer by leaving it turned on than by turning it on and off at need, because powering up the driver sucked significant battery power each time you turned the light from off to on.

I have been wondering how the V2 model differs from the V1 — anybody know?
Both old and new models are for sale witha few dollars difference.

If the newer driver is better, for modding, it’d be worth paying more.
If it’s a different LED, which I”d expect to swap out anyhow, not so much.