29 replies to this topic

[scorpio_fish]

It's not about streamlining, it's about not having your SPG drag over the bottom if you want to make a shot close to the substrate. When you only have your SPG as a backup for your AI computer then I guess you can stow it out of the way

When an SPG is attached properly, it will not drag on the bottom no matter how close you are to the substrate.

[Drew]

Before we get too far off topic, let's remember that the OP asked about the ease of using hoseless computer. In my little experience, the newer generation hoseless computers are definitely more reliable than the older generations. With Suunto, you have to match and sync the xmitter with the computer before anything else. The Uwatec and Aeris don't have to and obviously the manufacturers are not worried about crossed signals.
Of course, choice of computer also includes choice of decompression models, which is another whole subject in itself. RGBM with deep stop vs Buhlman with heart rate vs Haldane with tables. I think you best should also consider the computer model as part of your decision making. A computer is for showing deco limits and those vary between different deco models.

When an SPG is attached properly, it will not drag on the bottom no matter how close you are to the substrate.

PS: George, let's not give Craig ideas on that vibrating SPG and where to store it.

[frogfish]

Robert, I'm surprised you are not simply breath-hold diving, you old Luddite! The heart-rate monitor is not there to tell you you are having a heart attack. It's there to take your heart-rate/body function into consideration when calculating your deco - or did Dr Buhlmann base his model on your supreme example of human fitness?

John, I had no idea that there was a new decompression algorithm out that could "take heart-rate/body function into consideration when calculating your deco". I didn't even know someone had come up with a theoretical formula (or any data) that could meaningfully relate changes in heart-rate to increased DCI risk. Or is the Galileo's heart-rate function something like the Uwatec SmartPro's "micro-bubble level warning feature" - "best guestimates" based on the very best science that some guy in the marketing department found on the internet?

Neither compasses nor SPGs are life support equipment as you do not die if they fail. Your air supply is your life support equipment. I don't need fully redundant computers to make good decisions on a 30' max dive.

Sure, nobody needs redundant computers on a single 30 meter dive, but if you don't have redundant time and depth information then aborting the dive is probably the right course. More important, if you are on a dive trip, only carry one computer, and it fails, then it's back to tables and you'll need to clear for 24 hours or more before you resume diving. Same deal even if you have a spare computer that lives in your cabin.

It's not about streamlining, it's about not having your SPG drag over the bottom if you want to make a shot close to the substrate. When you only have your SPG as a backup for your AI computer then I guess you can stow it out of the way.

Notwithstanding that Scorpiofish was talking about integrated octo-inflators (and I agree with him), not SPGs, there is absolutely no reason for the SPG to drag on the bottom. As Drew knows very well, I don't claim to be DIR at all (and I also agree with Craig that "a DIR photographer" (like a photographer dive buddy) "is an oxymoron"). Anyway, I usually keep my analog SPG clipped to the left chest D-ring, not the one on my left hip where George insists it should go. I can read it at a glance, no hands, just as easily as the people who with transmitters on the 1st stages.

I do use happily wear my my spare 2nd on a necklace instead of a scum-ball. And in fairness to "real" DIR divers (whoever they are), I've never seen even a wannabe neo-DIR diver drag their SPG over the bottom. Nor a necklaced spare 2nd. It always amazes me how many ostensibly experienced PADI-trained divers think its ok to swim over reefs dragging a huge console (depth gauge, SPG, computer, compass) and a nice bright yellow "Octopus" over the corals. They also seem to get very offended if you mention it to them, even if you do it very nicely.

Of course, choice of computer also includes choice of decompression models, which is another whole subject in itself. RGBM with deep stop vs Buhlman with heart rate vs Haldane with tables. I think you best should also consider the computer model as part of your decision making. A computer is for showing deco limits and those vary between different deco models. PS: George, let's not give Craig ideas on that vibrating SPG and where to store it.

I agree with Drew 100% on this. Only a few weeks ago I heard a diver disparaging his new Suunto RGBM computer "because it doesn't give me as much bottom-time as the Uwatec Aladdin did, especially on a trip doing several dives a day." I had blithely assumed the reason people become Suunto owners is that they wanted their computer to use a better algorithm which takes into consideration repetitive multiple-day diving, reverse profiles, etc. I just wish Suunto would release a RGBM computer with a cleaner configuration - multiple gas mixes yes, but no wireless, no compass, no email, etc. With a big, easily readable display, and at a price that makes it possi ble for me to buy two of them without taking out a bank loan.

The other factor that needs to to be taken into consideration, of course, is reliability. I know that it's not a question of whether a dive computer will fail, but when. That said, I haven't very good luck with Suunto computers in the past.

If Suunto really does come up with a computer with a vibrating anal probe, I'll think I'd like to sign up to be their agent. It opens possible vistas of whole new markets for "recreational deep diving."

Edited by frogfish, 07 May 2007 - 06:31 PM.

[cmm1970]

I always enjoy seeing how these threads twist and turn.  Who would have know a DIR debate would get started?  Keep up the needling.

[Drew]

Mike, stop stirring and go buy a computer please.

[Cerianthus]

If bottom time is what they want, why not use the old US Navy tables :-)

[scubanerd]

FWIW, I have owned 3 different Uwatec computers. The first 2 used the 'old' style transmitter and the new Smart Z uses a new transmitter that I am told fixes the blink out problem. I shoot video so no flash to trigger the blink out, however my wife shoots with S&S DX90's and 125's and she was always causing my computer to blink out. With the new Smart Z it has not happened even when I held my computer next to her flashes while firing them...

Ryan

[dsbierman]

Sorry, I'm very late to this discussion, but I found it a must read. Let's assume for one moment that all of the wireless air intergration computers work PERFECTLY. Now, I realize that you, and you alone are responsible for checking your own air. That said, is it possible for a third party (i.e. your DM) to check your tank pressure on the boat without setting up a separate SPG? Frankly, as an Instructor myself, I don't want to be held liable for putting an empty/leaky tank on someone's shoulders. Secondly, as a non-wireless user, how easy is it for me to check my buddy's air underwater? Granted, I can ask him/her for the reading, but I also have an instructor's habit of checking the guage with my own eyes when my diver is focused on the fish.

Edited by dsbierman, 24 July 2007 - 06:07 AM.

[John Bantin]

Sorry, I'm very late to this discussion, but I found it a must read. Let's assume for one moment that all of the wireless air intergration computers work PERFECTLY. Now, I realize that you, and you alone are responsible for checking your own air. That said, is it possible for a third party (i.e. your DM) to check your tank pressure on the boat without setting up a separate SPG? Frankly, as an Instructor myself, I don't want to be held liable for putting an empty/leaky tank on someone's shoulders. Secondly, as a non-wireless user, how easy is it for me to check my buddy's air underwater? Granted, I can ask him/her for the reading, but I also have an instructor's habit of checking the guage with my own eyes when my diver is focused on the fish.

Some of these computers allow you an extra transmitter to fit to your buddy's (trainee's) tank so that you can monitor their air while underwater too!

[IMSushi]

dsbierman, I use the Oceanic Atom 2 wireless air integrated computer. As a back up, I also have attached to my 1st stage a pony bottle pressure guage: http://www.oceanicwo...ponybottle.html This is a cheaper way to go than a totally separate SPG, and you really can't check it yourself (buddy required...separate topic!). But, after my tank is supposedly filled on the boat between dives, I can check to be sure just by reattaching my reg. and cracking the tank and peaking at the pony bottle guage.

The pony bottle guage really allows for streamlining of all of those hoses comming off of your 1st stage. One for your primary reg and one for your low pressure inflator/Air II. Thats it! OK. I have a third for my drysuit inflator if I'm diving at home.