newbie question about diving with just an SPG

spatman · Post by **spatman** » Fri Feb 08, 2008 8:29 am

i've noticed that many of you dive with just an SPG and no other instruments on your console. i understand that a lot of this has to do with reducing drag and unnecessary clutter.

but i'm specifically interested in knowing why you don't dive with an analog depth gauge, relying solely on your computer for depth. what happens when your computer goes kaput? do you rely on your buddy for a safe ascent? are your dive senses so keen that you can safely just your rate of ascent?

please enlighten me with your secret ninja dive knowledge.

Grateful Diver · Post by **Grateful Diver** » Fri Feb 08, 2008 8:59 am

On standard recreational dives, if my dive computer were to go kaput then yes, I'd signal my buddy what happened and thumb the dive. Between my buddy's computer and my own body feedback I am certain I would be able to make a safe ascent, with reasonable safety stops.

For tech or solo diving, I always wear a backup device ... in my case, a Uwatec bottom timer.

... Bob (Grateful Diver)

spatman · Post by **spatman** » Fri Feb 08, 2008 9:57 am

Grateful Diver wrote:For tech or solo diving, I always wear a backup device ... in my case, a Uwatec bottom timer.)

so the Uwatec has a depth gauge as well as the timer, i assume?

thelawgoddess · Post by **thelawgoddess** » Fri Feb 08, 2008 11:00 am

no, the uwatec bottom timer is just a timer - backup for if your computer dies; not backup for if your spg dies.

and yes - if it came down to it, you really should be able to safely ascend at a rate that won't kill you without the help of any gauges or computers whatsoever. hopefully you aren't diving solo, haven't lost your buddy, and his/her instruments can be of some assistance for your "prompt" ascent ... but if not, a rig that emits bubbles and some sort of light source so you can see said bubbles should help.

spatman · Post by **spatman** » Fri Feb 08, 2008 11:13 am

thelawgoddess wrote:and yes - if it came down to it, you really should be able to safely ascend at a rate that won't kill you without the help of any gauges or computers whatsoever. hopefully you aren't diving solo, haven't lost your buddy, and his/her instruments can be of some assistance for your "prompt" ascent ... but if not, a rig that emits bubbles and some sort of light source so you can see said bubbles should help.

that makes a lot of sense, especially using bubbles as a guide. thanks.

and welcome back, you've been missed around here.

boydski · Post by **boydski** » Fri Feb 08, 2008 11:21 am

spatman wrote:
Grateful Diver wrote:For tech or solo diving, I always wear a backup device ... in my case, a Uwatec bottom timer.)
so the Uwatec has a depth gauge as well as the timer, i assume?

Yes, the bottom timers display depth and time.

Like Bob, I typically only use one computer on recreational dives, but on technical dives always have a backup depth/time device. In my case it is usually another dive computer in gauge mode.

LCF · Post by **LCF** » Fri Feb 08, 2008 11:36 am

For recreational dives, my teammates are carrying my backup depth gauge. In addition, if we have reached the turn point of the dive, I should have SOME idea of the depths we're at as we return, because I was paying attention as we went out. Same thing in a cave; if my depth gauge fails, the dive is over and we are on our way out, but I should have a pretty good idea of how deep I've been and for how long when that happens.

Grateful Diver · Post by **Grateful Diver** » Fri Feb 08, 2008 11:36 am

spatman wrote:
Grateful Diver wrote:For tech or solo diving, I always wear a backup device ... in my case, a Uwatec bottom timer.)
so the Uwatec has a depth gauge as well as the timer, i assume?

As Scott said ... the Uwatec registers both depth and bottom time.

Note that is ALL it registers ... it is not a substitute for a dive computer, nor does it give you much in the way of dive log info ... just depth and time. Makes a handy backup device, but that's about all it's good for.

... Bob (Grateful Diver)

boydski · Post by **boydski** » Fri Feb 08, 2008 12:19 pm

LCF wrote: Same thing in a cave; if my depth gauge fails, the dive is over and we are on our way out, but I should have a pretty good idea of how deep I've been and for how long when that happens.

Hi Lynne,

You'll probably laugh about this, but one of the "primary" reasons I always carry a spare computer/timer with me on cave dives is the same reason I always carry three backup lights. On numerous dives, while in the water doing our final bubble checks, etc., someone's backup light or computer/timer will fail before the dive even starts.

I just hand them my spare, and it keeps us from having to call a dive before it even starts. I also keeps me from having to crawl out of some hole in the ground with full tanks....

I do the same thing on week long live-aboard trips. One of my spare computers dives with me (in my pocket) all week. Without fail, someone's computer dies mid-week and borrows my old computer, which is pre-loaded with nitrogen for them. Not ideal, but better than starting over on an expensive overseas vaction.

Sounder · Post by **Sounder** » Fri Feb 08, 2008 2:24 pm

I'll be wearing my computer and Mrs. Sounder's computer in Bonaire for the same reason Scott pointed out... so that if one goes to crap, the other is "up to date" on my profiles.

Around here, my buddies are my redundant gauges and they'll get me back to the surface if I have a failure... and that's if I can see them! My buddy should be able to guide me to the surface in the event that I lost my mask and couldn't secure a redundant one (doubtful but possible)... a fun drill (just be ready to buy the first round after the dive): "oops, I lost my mask."

Tom Nic · Post by **Tom Nic** » Fri Feb 08, 2008 3:15 pm

boydski wrote:I do the same thing on week long live-aboard trips. One of my spare computers dives with me (in my pocket) all week. Without fail, someone's computer dies mid-week and borrows my old computer, which is pre-loaded with nitrogen for them. Not ideal, but better than starting over on an expensive overseas vaction.

Sounder wrote:I'll be wearing my computer and Mrs. Sounder's computer in Bonaire for the same reason Scott pointed out... so that if one goes to crap, the other is "up to date" on my profiles.

Excellent ideas, and ones that had never crossed my puny brain before! Very cool...

Peter Guy · Post by **Peter Guy** » Fri Feb 08, 2008 3:25 pm

Lynne and I were able to get a couple of Suunto Mosquitos for a very good price. On trips they are our watches -- of course they also serve double duty as backup computers/bottom timers/etc.

Have spares can be a very good thing.

spatman · Post by **spatman** » Fri Feb 08, 2008 3:28 pm

thank you, everyone, for the excellent advice. there is not a day that goes by without adding to my ever-increasing respect for the members of this board.

someday, i will be of the ninja elite, and training the noobs as well.

Sounder · Post by **Sounder** » Fri Feb 08, 2008 6:31 pm

spatman wrote: someday, i will be of the ninja elite, and training the noobs as well.

Someday, Forest Worm, you will be ninja diver. ...but, you must flutter kick before you go the way of the frog.

One day, when you are ready to leave your master, you will be able to walk across Cove 2 hill without slipping in goose poo and then shoot a bag without your master snatching it above you.

spatman · Post by **spatman** » Fri Feb 08, 2008 7:45 pm

Sounder wrote:
spatman wrote: someday, i will be of the ninja elite, and training the noobs as well.

Someday, Forest Worm, you will be ninja diver. ...but, you must flutter kick before you go the way of the frog.

One day, when you are ready to leave your master, you will be able to walk across Cove 2 hill without slipping in goose poo and then shoot a bag without your master snatching it above you.

awesome.

makes me want to go and rent some old ninja and kung fu movies.