Dive light from E-Bay -- Great buy!!!

[FiddlerOnTheRoof]

The 18650 battery is too small. The light works best with the bigger 26650 battery. I am using the 26650 and on 2 consecutive dives it performed great with no noticeable drop in brightness.

 

[spoolin01]

Sure it's a bigger battery but otherwise the same. A 4000MAh 26650 battery at 4A draw will last one hour according to the simple math. Probably less than that in reality. So if it's lasting longer, the explanations have to be considered. On one side is the mode of use (battery capacity, brightness setting, duration of on-time). On the other is the light itself. If the light is lasting longer than that simple capacity vs draw-rate calculation implies, the question of how the circuitry is (or is not) controlling output is still an active one. To go longer, it has to be less bright.

My light meter died, but I've got a replacement coming. I'll take some measurements to see how brightness fares over burn time. I've got a few other LED lights that I know have some level of output control via the driver circuitry that I can use for comparison.

For my interest, I'd like at least 60 minutes of fairly constant output, or there's no point in going this route for video use (not that it couldn't be used anyway, just that better options should be available). There are better daytime lights IMO, and for nite use I'm looking for something that also works for video.

None of this changes the fact that if it's durable, it's a nice bright light for an incredible price if it does what you want. I can see this being my main outdoors light now, even if I don't adopt it underwater.

 

[FiddlerOnTheRoof]

Received my second light last week and took it for a dive yesterday to about 90ft. Worked great also! Just so you guys know I also have a Hollister led25 canister torch (1250+ lmn) that I take with me and let me tell you... These $25 lights are just as bright. The only difference is that the spot on the Hollis is tighter and battery life is longer and the Hollis is rated to a greater depth. The Hollis led 25 also cost $600 versus $25.

So I won't be taking them to the Andrea Doria but for recreational diving I think they are great for the price!

Nice e-bay lights for $25!!

---------- Post added May 4th, 2015 at 12:53 PM ----------

I don't know if it is a good light for video. I'm not a video expert. But if you are on a budget and need a nice light to go do some recreational diving I think the price and quality is great!

 

[Rustydiver]

OK, I'm sold. Ordered one yesterday. Heading to Florida at the end of the month for some wreck diving.

 

[dberry]

Two lights and two batteries arrived today (8 days in transit, but no complaints - it was free shipping.)

First observations:
(1) careful how where you point it while screwing on the cap to the battery compartment - mine was in SOS strobe mode and pointed towards my face. Doh!! Flash of light and pain! (It is a very bright light.)

(2) switch is very funky... I'm glad I read Spoolin01's hint about how to change light modes - it's not obvious. Turn the ring to "on", then a bit back towards "off" (but NOT all the way back to off), then back to the "on", and you cycle through brightnesses. Repeat in the other direction from "off" for the strobe mode indent to go from SOS (dot dot dot - dash dash dash - dot dot dot) to fast, medium and slow strobe flashes. After turning to "off", it always defaults to "brightest" for "on" and SOS in strobe mode.

I suppose it would have been nice to have included a 1page "manual", but I shudder to imagine describing this weird mode switching using Chinglish or pictograms. (I doubt most readers will understand my description above without playing with a light at the same time.)

The biggest problem I foresee: switch is much too easy to rotate and has no lock for the "off" position. This is a real pity, as it's such an easy little thing that'll make a very real difference. I may try slipping a thin disk of plastic the size of a US quarter inside the battery end-cap when it's out of the water. (keeping the battery in, but impossible to accidentally turn on.) It will still most likely get switched on by accident in a dive, to the great annoyance of fellow divers.


(3) The combined 3-parabola reflector / heat sink seems to be a very hefty piece aluminum (that's good), but the polycarbonate "lens" will scratch easier than glass.

(4) I agree with comments that the thread machining is a bit rough, but I was more concerned by the few tiny bits of aluminum shavings left inside. These could damage the O-rings, or at least prevent a good seal. Not a deal-breaker - but it's a really good idea to unscrew everything and thoroughly wipe / blow it out (and to lightly lube all the O-rings, of course.)

Overall - I agree with others in this thread. It's a great light for the price, and I'll be very happy (as long as it survives a few dives as well as other posters have reported.)

OBTW, I bought two 4000mAh 26650 batteries from the same eBay vendor ($14 / pair) - supposedly with PCB ("protection").

I also bought a Li ion battery charger from the supplier OldSchoolTo mentioned ("liionwholesale.com"). It was a bit more than some other chargers, but this one seems really really nice, with a LED display showing voltage and charging status of each battery, and switchable charging currents (1 Amp for larger batteries, 0.5 Amp recommended for smaller ones.) Li ion batteries are both fairly expensive and more sensitive to charging conditions than some other types of rechargeables, so I couldn't see going cheap on the charger, shrug.

I got the one with the optional DC car cigarette plug / USB charging feature in addition to AC current.
EFest LUC 2 Bay LCD and USB Li-ion Battery Charger, w/ Car Adapter – Liion Wholesale Batteries

Here's my photo of this nifty little charger and the other toys:

Thanks for the tip, Peter, and feedback from all the others on this thread.
-Don

 

[FiddlerOnTheRoof]

No problem Don! I've done a few dives with them but nothing past 100ft yet. So far so good and no problem with them turning on accidently yet. I now own 2 of them and actually used on the other day as a beacon on my safety al80 that I left on the mooring line blinking.

---------- Post added May 6th, 2015 at 09:57 PM ----------

OK, I'm sold. Ordered one yesterday. Heading to Florida at the end of the month for some wreck diving.

Just don't go past their depth limit!

 

[lucca brassi]

stunning

 

[dberry]

Hi Lucca! I checked out your candlepower forum link - amazing! An incredible source of info about making and using dive lights. It must be amusing for you to read this thread from us gaffers getting excited about these $25 chinese dive lights! I'll admit I don't really know squat about the subject, but I really don't want or need to build my own canister light system. I just wanted something "bright", waterproof and convenient, and the price seems a no-brainer. Since you are a serious "light-guy", it would be interesting to hear your take on these lights, tho. What they're good for, not good for, or anything else.

Cheers,
Don

 

[kelemvor]

Are you guys using 26650's with or without button tops?

 

[spoolin01]

FWIW, I've been using flat-top 18650s harvested from a laptop battery for this and other purposes. Generally they seem to work fine, since the contacts in most applications are themselves "button-top" in one fashion or another. Some chargers have a little less button and getting a good contact requires more care.

I've just ordered some thin round rare-earth magnets off eBay to have on hand should it be necessary to have a button on the batteries in some application.