reason for two computers??

[The Kraken]

Well, Pug, I will admit that I haven't.
Please, for my own edification, enlighten me.

 

[Geezer]

I'm always interested in learning more - what is the technique?

 

[Uncle Pug]

Well... have you figured out how to tell what your SPG will read before you look at it?

 

[TX101]

"Get the right tool for the job, kids!" as Mr. Natural would say (including your gourd)!!!

I thought he used to say:

"I don't drink ..."

"I don't smoke ..."

"I don't sniff no coke"


well, you guys may not know Mental as Anything in the US.

 

[Geezer]

Even with my very limited experience, I'm finding that, if I'm aware of my breathing rate and dive time, the SPG seems to track where I expect it to be.

Still unsure how to relate that to judging depth, however.

If I'm diving a site that has a known depth, and if there is enough vertical visibility, I can make a rough guess as to where I am in the water column. Last weekend, though, 15 foot max visibility made it sort of difficult.

 

[TX101]

Well... have you figured out how to tell what your SPG will read before you look at it?

I don't think you can equate them. I'm not bad at guessing my SPG, but I'm not great either.

But I have no idea how to guess my depth. Depending on where you are, 20m looks the same as 80+m. You need a torch if you are going below 20m in the UK. You may have an idea from 10m to the surface because the water gets lighter but thats about it. When I went to the red sea, I estimated my depth at around 10-12m, then looked at my guage and I was at 25m (and could still see the surface!!!!)

 

[Uncle Pug]

I'm not suggesting the you dive without an SPG or a Depth Gauge. However I have developed a sense of what my SPG will read to the point that I am usually spot on in *guessing* it before looking even at odd minute intervals. I usually suggest that folks learn to do this by checking their SPG every 5 minutes after guessing what it will read. Do this enough times and you will be surprised. You will not only develop a sense of what your gas status is but also calibrate your internal clock.

The same thing can be done with your depth. Practice guessing your depth before looking at your depth gauge. It might surprise you.

Again, I'm not suggesting that you don't use a depth gauge... just that you calibrate your internal depth gauge. That way you won't be in a pickle if your computer(s) take a vacation.

BTW... I've forgotten my Stinger on more than one occassion and do the dives anyway.

 

[wscdive]

The only time I use two computers is when i am instructing on multiple dives. If one was to die i can safely keep diving on the other.( I can't very well tell clients that they cant get certified because i can't dive, we routinely do morning advaced certs and afternoon open water so its alot of diving) In a recreational situation I wouldnt be deco diving anyway and if the comp quit I can safely ascend with no worries. I always carry a bottom timer depth gauge(uwatec makes a nice one that shows ascent rate) as a back up and as someone else said in a tech situation i would have my back-up deco plan ready. The only place I would use a buddies comp as back-up is in a cave. (because of the nature of buddy-diving in a cave your times and depths should be nearly identical)

 

[RSdiver]

I don't think diving with 2 computers is essential, but given the recent new, low cost products on the market, it sure makes it affordable (compared to years ago).

Vie wrote:
just out of curiosity, are you getting slightly different depth readings? Back when I was using a Cochran, my computer would be reading shallower than everyone else's. I have also seen Suunto Cobras showing slightly shallower depths than Pelagics at identical depths.

I have owned a US Divers Scan4 (aka Oceanic DataMax Pro) for 10 years/900+ dives and is still going strong (12 tissue group Mod-H algorithm). I recently destroyed my cheap standard wristwatch (purchased in Hat Yai Thailand for 200 Bht) while painting my house, so thought I would replace it with a Suunto Mosquito. This is really an inexpensive computer and great too, only lacking a NDL bar loading graph that I've come accustomed to.

I've only been on a few dives, none deeper than 60 feet, but the Mosquito tracks my DataMax Pro to within 1 foot of depth and close on NDLs too. Then they came out with the D-9 and I have the chance to upgrade via exchange so will probably do that.

 

[htn123]

I'm not suggesting the you dive without an SPG or a Depth Gauge. However I have developed a sense of what my SPG will read to the point that I am usually spot on in *guessing* it before looking even at odd minute intervals. I usually suggest that folks learn to do this by checking their SPG every 5 minutes after guessing what it will read. Do this enough times and you will be surprised. You will not only develop a sense of what your gas status is but also calibrate your internal clock.

The same thing can be done with your depth. Practice guessing your depth before looking at your depth gauge. It might surprise you.

Again, I'm not suggesting that you don't use a depth gauge... just that you calibrate your internal depth gauge. That way you won't be in a pickle if your computer(s) take a vacation.

BTW... I've forgotten my Stinger on more than one occassion and do the dives anyway.

Thanks Uncle Pug. I guess, when I have dived a gazillion times like you then I can tell my depth by how much I have peed in my suit just kidding. But until then I will don on my 2 computers and one depth watch just to be sure.

One time, I was crusing and hunting for fishes and forgot to look at my depth gauge for about 10 minutes, looked back and holly cow, I was at 110!!!. Hauled my butt back to 90 and then upward a bit. That is why I carry 3 and watch them every 5 minutes since.