Ultrafire DV-S9 diving light?

Thanks for the infos. Will definitely be marking it, and using it for low-risk applications.

I usually recharge my batteries when they reach about 3.6V - I hate the thought of walking my dog, and not being able to use turbo mode, since most of the lights that I own draw a high current and cause a considerable voltage sag. That’s why I have plenty of VTC6 and 30Q lying around and I used one for the DV-9, otherwise a high drain battery would probably be overkill for this light. The one that I used had been recharged less than ten times.

With nightstand lights, I’ve been testing how long they last in the lowest mode. But after this experience I’ll probably put an end to that, and check the voltage more regularly. Or I’ll just use my Olight S Mini with CR123A - those cells almost seem to last forever! :slight_smile:

I’ve got some low capacity ‘junk’ cells. I use those for testing unknown situations. Not of much use for high draw applications but work OK for other stuff.

“So… anyone else have one? Played around with it any? Solved how to keep the cell from draining when not in use?”

I just unscrew a few threads , and no drain.

¼-turn is usually enough to break contact, and not engage if you squeeze it together, but I give it about ½-turn to be sure.

With battery in place and back off, turn the switch on. Then screw it slowly in. It will light when it makes contact. Or reverse the process. You can tell when it loses contact. Plus, that tiny amount is not enough to compromise waterproof integrity if that is an actual issue.
Some dive lights use screwing the back in/out as the way to turn them on. It’s simple, effective, and removes one other source of potential water entry via a switch.

But that puts the tailcap and rest of the light at 2 different potentials, VASTLY increasing the potential for corrosion with the slightest scuff to the anodisation. The water acts as a bridge across the non-contacting pieces.

I’d much rather have the magnetic slider that the DV-S9 has. Zero chance of ingress from there.

Mmmm, the light I currently have that works that way is plastic so corrosion is not an issue. It’s by Underwater Kinetics and is designed and specifically made for diving by a diving light company. There are similar dive lights via similar companies.

One of their high power LED actually has a heat sink that comes out thorough the front lens since it does not have a good path to heat sink the LED pill via the plastic body. My 3xC-cell light has a full length metal tube down inside the body to draw heat out of the pill and distribute it.

The UK light is fine. It’s a backup light so rarely gets used. I’m looking for something smaller, lighter, and working toward migrating more exclusively to Li-on. Single cell lights are now almost as good as my 4 year old canister light. Not quite, but pretty close.

Just took some beamshots and the UltraFire doesn’t look more green than a different light with CW emitter, so it’s probably just my eyes that have become accustomed to neutral white tints.

Thrunite TN4A XP-L Hi NW, Olight SR52UT XP-L Hi, UltraFire DV-S9 XM-L2

This particular switch is pretty clever. There are no springs and the only part for potential corrosion is the magnet in that little slider. A couple other “dive lights” with Hall sensors I got have springs and things on the outside. Sure, no hole through the light for a switch, BUT the mechanism is cheap carbon steel and rusts out fast in saltwater immersion use. This is the first light I’ve gotten that does not do that. Seems reasonably solid.

FWIW, the seal on the back of a twisty is just as vulnerable when static as dynamic as long as the O-rings are in good shape, well lubed, and not contaminated with cat hair or other debris. Most floods of a properly designed light are user errors. MANY floods on Chinese lights are due to shoddy materials and poor workmanship. I don’t trust ANY of them until checked out thoroughly and defects corrected……if possible.
It’s one thing to have a light fail on a dark walk. It’s entirely another if you are depending on it during a dive. That’s why we carry 2 (or more) lights.

Yep, “two is one, one is none”…

Does that red ring unscrew so you can remove the switch? It does on the UKing but I didn’t try it DV, which I gave away to another diver.

Yeh, absolutely. Was wondering what was its purpose, so of course had to try it. :smiley:

All it does is keep the slider from falling out.

If you do take out the slider, it’ll only work if the “polarity” is right, so if it doesn’t turn on, remove it and flip it around.

Took the UKing (pretty close to the DV) on a dive yesterday. Used it for 1 hour with a Lii-26650. Worked fine, nice spot. Came back with half capacity.

Yeah, forgot offhand what I measured, but I think it was under 2A.

Think I got an old Rat Shack 26650 (“DE”, “Digital Energy” or something) in it, not any of my LKs. <2A ain’t gonna stress it out much.

Flydiver- were you in salt water or fresh? How deep did you go?

Salt. This wasn’t a deep one, 60 feet/68 minutes. What I like about this light is the apparent lack of external springs that rust out in many of the other models of cheap dive lights not ACTUALLY designed for serious diving. This one might work out. Oh, and NO modes…just the slider from dimmer > full on. Gotta like that.

I picked this up recently to check it out: 5000lm XML L2 LED Scuba Diving Underwater 500M Flashlight

It’s maybe 200 lumens and wouldn’t survive a prolonged exposure in a mud puddle. It’s a joke as a dive light and pretty much a lousy light.

But… but… it’s a Probe Shiny! :o

They sure do seem to love ’5’s, don’t they? 5000lm, 500m depth, what else? :smiley:

Hey, they even include a 3×AAA holder, to really belt out those 5000lm!

:person_facepalming:

Interesting. I will keep my eye out for a bargain.

Since most members here have a Convoy S2+ and C8 flashlight, I took a couple of photos of the DV-S9 next to them.

Unfortunately, mine stopped working after dropping it on lino flooring - from only about 2½ feet! :person_facepalming:

I took a (blurred and grainy) photo, anyway.