11 Oct 2006 16:08:41
Mark
Suunto Vyper desat time

I have dived tables for 10 years and just bought a Suunto Vyper dive
computer. According to the PADI RDP if I dive 40 feet for 60 minutes I
am an 'N' diver. If I have a surface interval for longer than 5:19 I am
a 'new' (not 'A') diver. I was under the impression that this is my
desat time. Time to desaturation. I am aware that the Vyper displays
the no-fly time, but does it display this desat time?



12 Oct 2006 09:57:28
Dirk Macke
Re: Suunto Vyper desat time



Mark wrote:
> I am aware that the Vyper displays
> the no-fly time, but does it display this desat time?

No.

HTH,
Dirk


12 Oct 2006 07:57:35
Lee Bell
Re: Suunto Vyper desat time

Mark wrote:

> I am aware that the Vyper displays the no-fly time, but does it display
> this desat time?

Perhaps it does so indirectly. First, the concept of desat time is more
than a bit of a misnomer. You're never desaturated. Right now, you're
saturated to whatever ambient pressure you're in. This sounds a bit nit
picky, but it's important enough for the computer manufacturers to account
for it in their computers. That's why all of them automatically adjust
their calculations for altitude.

Most computers, probably the Suunto line as well, don't give you, for lack
of a better term, a desaturation time. What they do is turn off when
they've reached whatever point the manufacturer believes makes the question
moot. My Oceanics continue to display both nitrogen and oxygen graphs until
they drop to 0 (ambient saturation). At that point the computer turns off.
The display continues until the no fly time has expired. On my computer,
it's easy to tell this has happened. When the computer is on, it cycles the
display between SI information, next dive information, and the screen that
allows me to change the gas mix (nitrox). When it reaches desat, it stops
cycling and shows only the no fly time. When that expires, it turns the
display off too.

You also asked how you could plan the SI for the next dive. Most computers
are not set up to do that. Mine, for example, will tell you how long your
next dive will be based on your previous dives and SI, but does not allow
you to enter informtion that would allow to use it to calculate the SI
necessary to get a specific no deco time. Most of us combine experience
with some educated guess work. We guess at a SI that will be adequate and
then watch the computer to see when it agrees. Even this, though, is a bit
iffy. Keep in mind that, when your computer shows you a no deco time at a
particular depth, that's the maximum time it considers safe for a no deco
dive to that depth. In graphic terms, that's at the very top of the caution
zone. Most divers that depend on computers, like the top of the green zone
better. In other words, you're not likely to get the full measure of what
your computer says you are able to do.

There are programs that allow you to plan dives in more detail. Lucky for
me, Oceanic offers one for my computer. It's a simulator that runs on my
desktop or notebook computer. It works just like my computer, but lets me
simulate my planned dives in advance. I can run the dives and see what
surface interval I need before I leave the house. To do that, of course, I
have to have a pretty good idea of what the dives will be like. I don't
always have that. Being able to dive without knowing, in advance, what the
dive will be like, is one of the reasons I use a computer in the first
place.

Lee




12 Oct 2006 15:22:50
El Mecky
Re: Suunto Vyper desat time


"Lee Bell" <pleebell2@bellsouth.net > schreef in bericht
news:A4qXg.51661$KR1.44523@bignews2.bellsouth.net...
> Mark wrote:
>
>> I am aware that the Vyper displays the no-fly time, but does it display
>> this desat time?
>
> Perhaps it does so indirectly. First, the concept of desat time is more
> than a bit of a misnomer. You're never desaturated. Right now, you're
> saturated to whatever ambient pressure you're in. This sounds a bit nit
> picky, but it's important enough for the computer manufacturers to account
> for it in their computers. That's why all of them automatically adjust
> their calculations for altitude.
>
> Most computers, probably the Suunto line as well, don't give you, for lack
> of a better term, a desaturation time. What they do is turn off when
> they've reached whatever point the manufacturer believes makes the
> question moot. My Oceanics continue to display both nitrogen and oxygen
> graphs until they drop to 0 (ambient saturation). At that point the
> computer turns off. The display continues until the no fly time has
> expired. On my computer, it's easy to tell this has happened. When the
> computer is on, it cycles the display between SI information, next dive
> information, and the screen that allows me to change the gas mix (nitrox).
> When it reaches desat, it stops cycling and shows only the no fly time.
> When that expires, it turns the display off too.
>
> You also asked how you could plan the SI for the next dive. Most
> computers are not set up to do that. Mine, for example, will tell you how
> long your next dive will be based on your previous dives and SI, but does
> not allow you to enter informtion that would allow to use it to calculate
> the SI necessary to get a specific no deco time. Most of us combine
> experience with some educated guess work. We guess at a SI that will be
> adequate and then watch the computer to see when it agrees. Even this,
> though, is a bit iffy. Keep in mind that, when your computer shows you a
> no deco time at a particular depth, that's the maximum time it considers
> safe for a no deco dive to that depth. In graphic terms, that's at the
> very top of the caution zone. Most divers that depend on computers, like
> the top of the green zone better. In other words, you're not likely to
> get the full measure of what your computer says you are able to do.
>
> There are programs that allow you to plan dives in more detail. Lucky for
> me, Oceanic offers one for my computer. It's a simulator that runs on my
> desktop or notebook computer. It works just like my computer, but lets me
> simulate my planned dives in advance. I can run the dives and see what
> surface interval I need before I leave the house. To do that, of course,
> I have to have a pretty good idea of what the dives will be like. I don't
> always have that. Being able to dive without knowing, in advance, what
> the dive will be like, is one of the reasons I use a computer in the first
> place.
>
> Lee


Or just keep the tables handy. I tend to dive without a plan on my fundives,
just going in from the shore (mostly freshwaterdiving) and starting my
underwater stroll.

Every now and then a quick look on my wrist to see how I'm doing on "time
left on this depth", depth, airsupply and "time left on this depth with this
airconsumption".

at the surface I get the PADI RDP out, take max depth and total dive time,
calculate pressure group en find my wished for surface interval fro there.

Always safe.




12 Oct 2006 14:24:26
Ken
Re: Suunto Vyper desat time


"Lee Bell" <pleebell2@bellsouth.net > wrote in message
news:A4qXg.51661$KR1.44523@bignews2.bellsouth.net...
> Mark wrote:
>
>> I am aware that the Vyper displays the no-fly time, but does it display
>> this desat time?
>
> Perhaps it does so indirectly. First, the concept of desat time is more
> than a bit of a misnomer. You're never desaturated. Right now, you're
> saturated to whatever ambient pressure you're in. This sounds a bit nit
> picky, but it's important enough for the computer manufacturers to account
> for it in their computers. That's why all of them automatically adjust
> their calculations for altitude.
>
> Most computers, probably the Suunto line as well, don't give you, for lack
> of a better term, a desaturation time. What they do is turn off when
> they've reached whatever point the manufacturer believes makes the
> question moot. My Oceanics continue to display both nitrogen and oxygen
> graphs until they drop to 0 (ambient saturation). At that point the
> computer turns off. The display continues until the no fly time has
> expired. On my computer, it's easy to tell this has happened. When the
> computer is on, it cycles the display between SI information, next dive
> information, and the screen that allows me to change the gas mix (nitrox).
> When it reaches desat, it stops cycling and shows only the no fly time.
> When that expires, it turns the display off too.
>
> You also asked how you could plan the SI for the next dive. Most
> computers are not set up to do that. Mine, for example, will tell you how
> long your next dive will be based on your previous dives and SI, but does
> not allow you to enter informtion that would allow to use it to calculate
> the SI necessary to get a specific no deco time. Most of us combine
> experience with some educated guess work. We guess at a SI that will be
> adequate and then watch the computer to see when it agrees. Even this,
> though, is a bit iffy. Keep in mind that, when your computer shows you a
> no deco time at a particular depth, that's the maximum time it considers
> safe for a no deco dive to that depth. In graphic terms, that's at the
> very top of the caution zone. Most divers that depend on computers, like
> the top of the green zone better. In other words, you're not likely to
> get the full measure of what your computer says you are able to do.
>
> There are programs that allow you to plan dives in more detail. Lucky for
> me, Oceanic offers one for my computer. It's a simulator that runs on my
> desktop or notebook computer. It works just like my computer, but lets me
> simulate my planned dives in advance. I can run the dives and see what
> surface interval I need before I leave the house. To do that, of course,
> I have to have a pretty good idea of what the dives will be like. I don't
> always have that. Being able to dive without knowing, in advance, what
> the dive will be like, is one of the reasons I use a computer in the first
> place.

IN one word, no it doesn't display a desat time and I agree with all Lee
says.

What the Vyper does further is that it treats consecutive dives as part of
the same dive series AS LONG AS when you jump in for a dive you have not
reached your no-fly limit. Let me give you a typical example of how this
pans out, taken from real life.

You go to Sharm for a week's wetness. Day one you do two relatively shallow
dives so the dive guides can sort out the wheat from the chaff. Your
computer records these as dives 1 and 2. By the time you jump in on day two,
you have reduced your no-fly tme to zero. You go a bit deeper than the day
before, and you do a third dive a bit later in the day. The Vyper records
these as dives 1, 2 and 3. Next day, your no fly time runs out at midday BUT
you jump in at 10am and you do three dives again. Your Vyper records these
as dives 4, 5 and 6. The next day you do similar, and your computer now
counts up to dive 9. Now comes Thistlegorm Day. You go deeper perhaps, but
you're on Nitrox and you finish your second and last dive of the day around
midday. Computer up to dive 11. Next day, having used nitrox the day before
AND having finished early, your no-fly time has run out at 8am and your
computer starts at dive 1 again.

Odd? Maybe. Useful? Doubtful. Quaint? Certainly. Dangerous? Certainly not.

Ken




12 Oct 2006 11:35:28
Lee Bell
Re: Suunto Vyper desat time

"El Mecky" wrote

> Or just keep the tables handy. I tend to dive without a plan on my
> fundives, just going in from the shore (mostly freshwaterdiving) and
> starting my underwater stroll.
>
> Every now and then a quick look on my wrist to see how I'm doing on "time
> left on this depth", depth, airsupply and "time left on this depth with
> this airconsumption".
>
> at the surface I get the PADI RDP out, take max depth and total dive time,
> calculate pressure group en find my wished for surface interval fro there.
>
> Always safe.

Yes, but not always practical. A lot depends on how many dives you're doing
and how much time you spend how deep on each one. For multilevel diving,
more often done from a boat than from shore, it doesn't take long before
your total dive time at your maximum depths, exceeds what the tables say is
OK.

Having said that, most of us that learned to use the tables, get much of our
feeling for how long is enough, from them. Even when they're not practical
for planning the next dive, they're still not a bad way to guesstimate how
long a surface interval will work.

Lee




09 Nov 2006 20:25:17
Rick Hughes
Re: Suunto Vyper desat time


"Ken" <ken@k1at.freeserve.co.uk > wrote in message
news:eglho722ekd@news1.newsguy.com...
>

> What the Vyper does further is that it treats consecutive dives as part of
> the same dive series AS LONG AS when you jump in for a dive you have not
> reached your no-fly limit.


Good answer - I wondered what triggered the 'groups'




10 Nov 2006 00:22:00
=?ISO-8859-1?Q?S=F8ren_Reinke?
Re: Suunto Vyper desat time

Rick Hughes wrote:
> "Ken" <ken@k1at.freeserve.co.uk> wrote in message=20
> news:eglho722ekd@news1.newsguy.com...
>=20
>> What the Vyper does further is that it treats consecutive dives as par=
t of=20
>> the same dive series AS LONG AS when you jump in for a dive you have n=
ot=20
>> reached your no-fly limit.
>=20
>=20
> Good answer - I wondered what triggered the 'groups'=20

Hehe, if i remember correctly it does actually tell you in the manual,=20
at least on my Vytec (sold my vyper many years ago)

--=20
Best regards
C.T.O. S=F8ren Reinke
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