Ultrafire DV-S9 diving light?

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.

I just received a DV-S9 from FT - under $18 with BLF code, and i’m impressed.

Very nice 26650 light with magnetic switch for the price. Although it’s not a top performer it seems, i especially like the slider smooth operation…. I lubed the tail cap and o-rings while loading a 26650.

Not sure when/if i will have a chance to use it underwater. I got it as a backup to a (still unused) Solarstorm DX4. :person_facepalming:

PS: thanks to the above comments about the red ring preventing the switch to fall off. Mine was loose and i wasn’t sure what this ring was about nor did i noticed it would actually screw in. I would probably have lost the slider at some point. :+1:

PS2; I’m considering the DV-S5 as a backup to the DV-S9… Anyone tried it?
https://www.fasttech.com/product/6550301

Ewww. SOS mode in a diving light?? :person_facepalming:

Guess if you’re drownding you can flick it on so they could find your corpse later, but…

I don’t know how to test this but I believe the flashlight has a rather high parasitic drain. I left a battery in there unused for several weeks (< 1 month), and the battery was drained to below 2V when I tried to use the flashlight. As this isn’t a flashlight I would use once every week, I don’t leave battery in there anymore till I want to use it.

Even when “off”, the Hall-effect circuit for the slider draws something like 10mA. I mentioned it somewhere in this thread, so I think that’s how much it was. Not at all unusual or unreasonable. But yeah, I always gave the beastie a quarter-turn lockout when not in use.

Uhh, yeah, msg #2. :smiley:

Diving lights can also be used to pick up divers from the surface if they get caught in a current and drift away from their dive site. Sounds like a good idea to me.

Did a 31 dive vacation (Lembeh, Indonesia) beginning of the month. The DV-S9 worked without a problem going to 90+ feet a few times. The only unexpected issue was the magnet is embedded in the black slider. This was a sandy area (muck diving for weird critters) and the light would often rest on the bottom during during photos. It picked up iron grit. Didn’t affect use in any way. I didn’t even notice it until I got home and was cleaning things up thoroughly. I was able to remove it with small strips of tape and finished with high pressure air.

I did notice some minor fogging in the lens with use. There were a couple micro-drops on the lens. There was no evidence at all of flooding from the front or back. I think it was condensation, probably during assembly. Removed the front lens. The red rig holding the lens in has a silicone O-ring and there is a main O-ring under the lens. It’s been fine on extended dunk tests but has not gotten a dive test since the disassembly.

90’? Yeesh, think my eardrums would pop.

Good to know it holds up to that kind of pressure, though! So it’s definitely safe for me to use whilst changing a tire in the rain, then. :laughing:

You forget to mention a very important point about this particular light you show.
The light you show uses the tail cap as a switch.
So when you’re under water and it’s switched off, there’s a potential difference between the tail cap and the body, and THAT’s what causes electrolyses.
There is no electrolyses when the tail cap is in the “ON” position, because then the parts connect shorting the potential difference between tube and tail.

I’ve been ogling these slider diving lights for some years now, but i have never seen a review that answers the PWM question.
So, this one uses PWM (i guess they all do because it seems to be cheaper), and it’s reasonably high frequency PWM.
Can you try shining it on a black fabric and listen?
I bet it’s audible…

I really like the concept of a slider dimmer, but it’s often implemented quite crappily…
The travel of the slider is often very short too, but maybe that’s no problem.

Thanks for the review, Lightbringer.

That would make it a poor backup light if this is a problem. If it’s screwed down and on there should not be a problem, right? I have not had this particular issue.

Dive vacations are the best!

Some dive lights headed my way, will report after use.

I’m not the one to ask, as unless it’s 120Hz flicker from mains-driven LED nightlights or the like, I have a hard time discerning PWM.

Ironic, as 120Hz flicker from old-timey fluorscent tubes gives me migraines.

Hmm, what would that do?

Pretty much has to be, as falloff over distance is 1/d², and there’s already part of the Al tube between magnet and sensor.

I don’t have much of a problem giving it little shoves brighter/dimmer. This is maybe a cm or so.

No worries. Nice light…

Even screwed-down and off there’s still a solid electrical connection, so no electrolysis. Everything’s controlled by the e-switch (slider), and the whole case is at ground potential.

I bought an “Elfeland triple L6. 2 x 18650 cell Magn sw.
For use on boat NOT diving.

It’s lived on boat ever since. (The tools IN my garage round here go rusty)
and still nice and shiny.
Nice beam comfortable in hand. Cost around $16/17 AUD.
Still for sale at EBAY for 13.09 UK pounds del.

Some of mates use theirs for diving on pots etc. (12 to 18ft)
They reckon it fine for that.

More should have that magnetic. Variable or not, switch.
There’d be a lot less problems there hey.
This one has dual O-Rings right through.

I bought the Ultrafire DV-S9 from https://www.ultrafire.com. I really hate the angry blue led. It’s is also not that bright and there is no way to replace the led.
The lens retainment ring is secured with silicone. Not sure what I will do with the flashlight. I’m in the mood of torture testing it.

Mine wasn’t Angry Blue™. Cool at about the usual 6500K, but not colder.

Maybe you just lost the Tint Lottery…