DIR GUE and backup lights

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

It still is relevant if you have a team (team diving).

There has been a time or two when I have had to use my backup, surface, fix my light (or swap it out), and my buddy has handed me a fresh set of batteries from his save-a-dive kit. One set of batteries for 2 divers. Real convenient. Just like that, we're ready for another dive with minimal hassle.

I carry a spare bulb/reflector in my save-a-dive kit. It will fit a scout style (rat, whatever) light because the body diameter fits c-cells.

If you want to dive a cr123 powered light, thats fine. But for team diving in remote locations that require a fair bit of effort to plan, get to, and dive, simplicity and interchangeability are very important.

Excellent point, PfcAJ

Another reason for the 3 C cell models is basic battery capacity. A C cell has approx. 8350 mAh a cr123 has approx. 1550 mAh. Regardless of the source (LED, Halogen, Xeon, etc.) a C cells will always have a longer burn time than, cr123, AA, AAA.
 
I carry spare batteries for my backup lights, don't you? I also often carry a spare backup light. And the batteries in my BUL are AAs, which are easy to find almost anywhere.

David made it very clear that the 3 C cell requirement is no longer considered in force.
 
I do. I also carry enough spare parts to just about outfit a complete other diver. But those spares are also for my team should they need them.

Why limit your options? That's what doesn't make sense to me. If you don't want to standardize stuff, thats cool, but realize that there are some real disadvantages to it.
 
I carry spare batteries for my backup lights, don't you? I also often carry a spare backup light. And the batteries in my BUL are AAs, which are easy to find almost anywhere.

David made it very clear that the 3 C cell requirement is no longer considered in force.

Same here, spare batteries and lights. Given the number of times I or a buddy has had to use a backup (rarely), team sharing ability just isn't a factor to me for this case. It's a case of "You need a light, and your own backup isn't working? Here's my spare. Here's some spare batteries for it. And if that light doesn't work, here's my OTHER spare, and spare batteries for IT (if they aren't the same as the first spare, which isn't usually the case unless I'm experimenting with a new light)." In that situation who cares what batteries they use, as long as they meet the needs of the dive?

Guy
 
I do. I also carry enough spare parts to just about outfit a complete other diver. But those spares are also for my team should they need them.

Why limit your options? That's what doesn't make sense to me. If you don't want to standardize stuff, thats cool, but realize that there are some real disadvantages to it.

Sure there are disadvantages, and I assess them as minor to non-existent, compared to using the light that I find best for a given situation (and which is often lighter, smaller, and cheaper so that I can afford to buy and haul around multiple copies of it). If you're happy using C-cells all the time, more power to you; you know that you'll be unlikely to ever run out of burn time on any dive. And I'm happy using lights with AAs, CR123s, C-cells or what have you, tailoring the required light to the dive duration and the current state of technology, and thus not limiting MY options to a single battery size or chemistry. What I use won't affect you and vice-versa, which is not the case with other equipment issues. Underwater it's a binary solution set; a light works or it doesn't.

Guy
 
I think a smaller light may be helpful for me....eventually I'll try it out and see if it's the solution I'm looking for.

Hi Nichole,

I don't know enough yet to enter this technical gear debate, but I'm pretty little too & the 3 cell is huge on my torso ;-).

I have 2 little Salvo Rat Jr 2 cells which works great as backups for the type of recreational diving we are doing, ( Light Monkey sells a twin), but I can't speak for their functionality in technical diving. The Jr's are so small I don't even notice them clipped to my D rings. The CR123 batteries are said to last 4 hours & you can pick them up for a good price online in bulk or at Fry's. They are quite bright at night in tropical water & the batteries lived up to their promise lasting 3-4 dives - no problem, I love them. Of course they are not as bright during the day in our low vis waters- but they do the job in a pinch. You are welcome to dive one next time we meet :).

I did have a part blow in a remote place and it was an expensive PITA to get a replacement bulb. It was my fault 'cause I over tightened and crushed the back of the bulb which is said to never need replacement:shakehead:, but just in case I'd bring spare parts if you head out.

Kathy
 
Last edited:
Unless it also fails, and you have to then go to the tertiary backup. I personally don't like to leave things dangling for any length of time. For deco situations further back in the cave, I will leave my primary light on and clipped, but once I am in the daylight zone (and if visibility is good), I turn that off and stow it, and switch to a small "deco light" that is clipped off in my pocket with my wet notes. Most of my regular cave buddies do the same.

As far as I'm concerned, if you are exiting a wreck on your backup light, and it fails, then throw the dang thing down a hole, and never use it again ever!

Just out of curiosity, what class and which instructor(s)?

There was a guy in my Fundies class that showed up with something similar. During our equipment setup, the instructor said they weren't really necessary, especially at the fundies level without any stages clipped off, but that they weren't really anything that would impact the team. He didn't make a big deal out of it, and said it was his choice to leave them on or not, but the student cut them off his harness anyway.

I haven't ever used this little tweak, but I don't think two inches of cave line really impacts the team in any negative way either way. We always try to make the point that the DIR philosophy is about much more than just gear, and I think we give people the wrong impression when we criticize small gear customizations like this. I like people who make these sort of modifications, because it shows me they are thinking about their gear choices, and seeking optimization. A lot of people try these things out and figure out firsthand that they might not be ideal, which to me, is a lot more meaningful than just following standards without fully understanding them.

Tom
 
Regardless of the source (LED, Halogen, Xeon, etc.) a C cells will always have a longer burn time than, cr123, AA, AAA.

All else being equal yes, but often lights which draw less current are paired with lower capacity batteries.
 
All else being equal yes, but often lights which draw less current are paired with lower capacity batteries.

Yes. Also, the difference is not as dramatic if you're using more batteries (such as the lights that use 6x AAA or 4x AA). And as for cr123a batteries, the direct capacity may not be as long, but they're actually more stable and have a longer shelf life than alkaline C cells. (More expensive and harder to source, however, negates that advantage, in my book)
 
I like people who make these sort of modifications, because it shows me they are thinking about their gear choices, and seeking optimization.

You misspelled convoluted.
 
http://cavediveflorida.com/Rum_House.htm

Back
Top Bottom