[Review] Sofirn SD05 Diving 21700 Flashlight

Yeah I might not be able to get that many as Sofirn is offline. I’ll grab whatever is left.

@ Funtastic:

Should be more considerate. The idea is that if many people are interested in a 5000ºK version, they would make readily available.

Deobfuscation: I’m not Hank4U2 and I’m not Hank Wang and I’m not the other hank-plus-a-number.
I did post the pointer to the sale on the SD03. Hope y’all got a chance before the reseller sucked them all away.

@ hank:

So sorry. My bad! Corrected the OP.

Disclaimer: I’m not a prolific diver, I did about 200 dives, almost all in warm water (Caribbean like), few NJ shore and some quarry in PA.

I think considering a price this is a best recreational (take on the trip to warm place and dive) diving light available right now.
Timer sucks but it is not a show stopper, medium is enough for night dive, you don’t need to blind everyone and fish (on recreational dives you are in group 3-7 people - guide/dive master and 1 - 3 pairs), if you want to take a picture you still need flood light and here high CRI is nice.
High is nice for day dive when you look into holes checking if somebody hides there but then 3min timer is not an issue.

Another thing, for some time I was wondering about this thing fluoro diving, when you look for stuff that illuminates under blue/UV light. Blue is better, UV harms marine life and blue is causing better response, negative is that you see blue and you want yellow filter to get it out.
Anyway, I have Ferei W150 that I modded and put Royal Blue Cree XT-E in it. It is blue but it is not very strong.

I got 3 SD05s and I thought, lets put a blue LED in one.
Right, easy to say…
It is 6V LED, where do I get 6V blue LED, then….

it was like “wait a minute it already has a blue LED in it, it just has a phosphor on it”
So, I took some small pliers and removed dome from the LED, it wasnt gentle :slight_smile: and it already removed most of the phosphor from LED, I scraped a rest carefully using wooden splinter and now it is a blue light!!
It seems little less blue then Royal Blue but I think this is actually good.

LED Before

LED after

Close on low

Back in light with reflector

Next to Ferei W150 (guess which one is it :slight_smile: )

In real there are no violet rings visible just blue, smooth transition from spot to spill.

That’s some resourceful thinking there, arek98! :beer:

Hey, talk about modding a light!

Unfortunately arek98, your links to pics come up 404.

Should be fixed now
Also I hopefully will try it underwater in September. With current situation no way to go on the trip right now. Can’t wait, hope to see something nice :slight_smile:

I’m an authorized distributor mate.

I just tested mine and at 45°C it starts stepping down. That’s lower than the previous driver. The manual says 55 but it tests to be 45. That’s disappointing

Sofirn made a version without stepdown timer
https://sofirnlight.com/sd05-diving-flashlight-5000k-new-version-without-3-min-stepdown-p0116.html
https://sofirnlight.com/sd05-diving-flashlight-3000lm-p0016.html

Great! I’m glad to see Sofirn / Wurkkos finally removing timed stepped down and letting their “ATR” spread it’s wings.

Tempted by the removal of 3min. timer I’ve ordered one directly from the Sofirn site.

I took it for some diving the very first day and I must say I was pleasantly surprised: it easily outperformed my old HiMax H7 clone.
I’ve tested it up to 30m(~100ft), it was working without any problems (no photos this time though).

While being a really nice (maybe a little to small for me) light, it has one serious flaw (at least for me): 6000K LED.
I know it’s mostly matter of ones preference so I won’t hesitate to say: I hate cold LEDs.

So next step looked quite obvious: let’s disassemble the light, replace the emitter with 3000K XHP50.2 and be happy ever after.
Unfortunately Sofirn has made some some further changes along with the step-down timer removal.

1. Disassembly

I must say this was second most difficult screw I’ve dealt with this week.
I’ve 3D-printed few head adapters but all failed to remove the glued ring.
Eventually I’ve made hybrid printed key with four M3x8 screws that fit nicely into head’s cuts:

I’ve bought proper 5kg vise, screwed it into my desk and after a brief struggle I’ve managed to remove the header.
For my surprise Sofirn has exchanged blue thread locker to red one, that’s much more difficult to break.

2. PCB

This was the biggest disappointment here. The boost converter is gone, now we have most simple MOSFET driver that passes PWM-modulates battery connection directly to 3V LED :frowning:

Two ICs aboard are PIC12F1882 (datasheet) + AON6512 MOSET (datasheet).
Three hall sensors are TSH251 (datasheet)

3. Some scope dumps

PIC generates 20kHz frequency that looks like thins (measured on the LED connectors):

LOW:

MEDIUM:

HIGH:

And there doesn’t seem to be a difference in duty cycle when powered from 3.6V (left) vs. 4.2V (right):

4. Conclusions

Switch to new driver is a step-back for me, I realize this solution is 2x cheaper than boos converter but I feel such nice light deserves something better…
The good side of new design is SOIC8 package of PIC controller, so it should be easy to connect to and reprogram.

Anyway I now wait for 3000K XHP50.2 to arrive (I’ve ordered 6V version so I guess I’d have to reflow it to 3V pcb taken from this light…) I’ll let you know if when I succeed :slight_smile:

Btw. this seems to be my very first post on BLF so: Hi everybody! :slight_smile:

Welcome to BLF! What a great and informative first post.

No, the 6V XHP50.2 is different than the 3V version, you can’t reflow it to a 3V MCPCB.

Boost driver would lose Turbo at 3.7v which was around 8 minutes. The only good thing about the boost driver was 2hrs of High 920 lumens.

Thanks for that info! I’ll look for 3V XHP then.

EDIT:
The worst new of the day: CREE doesn’t make 3V 3000K XHP50.2, just two cold colors are available :frowning:

I’ve been holding off waiting for the 5000k version to come back in stock. I don’t buy much of anything anything cooler than 5000k or less than 90 cri anymore.

No, another good thing (and perhaps best thing) is the extremely well regulated consistent output of the boost driver. As a mountain biking light for night riding, this is a big plus! I’ve been tempted to pickup the new version without the 3min stepdown, but I’m turned off by the lack of regulated output and only 6000k tint option.

-Garry

Kewl, I knew none of this about diving. :laughing:

Only suggestion I’d make is to have the low-voltage warning come on a lot sooner. Below 3.6V, capacity is pretty much circling the drain. By 3.3V, it starts dropping like a rock. I was just watching this last night doing a capacity test of a coupla 18650s.

If you need more “cushion” to prepare, as in getting to the surface vs just pulling out a backup flashlight, much more notice/warning would be essential.

Could anyone confirm the ANSI measurement of the spare O-rings? Thanks!